length of the SWSA report, the complete text of Annexes E.A, E.B, and E.C are available only in the online version of the decadal survey report. Last, the panel notes that while it makes suggestions for actions in this appendix, the authority to make final consensus recommendations, conclusions, or findings rests with the steering committee.

E.1 INTRODUCTION

E.1.1 Expanding Importance of Space Weather

Except for climate change, space weather may be the fastest-growing geophysical hazard to society. Every currently operating spacecraft—and the many more that will be launched in the future¹—is subject to the constant variability and sporadic episodic nature of space weather. Understanding the physical causes of space weather, or at least characterizing the causes and impacts of space weather, is essential for the entire spaced-based economy, including mission and payload design, management of space traffic, developing mitigation response and recovery for space-based assets (e.g., communications satellites) and ground-based infrastructure (e.g., the power grid), safely exploring the heliosphere and solar system, and much more (Figure E-1). Space weather science and its applications are a necessary part of a foundation to enable NASA to achieve its vision of “exploring the secrets of the universe for the benefit of all.”

In the past 21 years, the Sun has had only mild and moderate levels of solar activity (Figure E-2). During this time, society’s reliance on technology sensitive to space weather—for example, GPS—has increased dramatically, with effects across a multitude of economic sectors, including defense, aviation, the power industry, emergency services, and the commercial space flight industry. However, the comparatively benign space weather environment

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¹ In the spring of 2022, the number of active satellites was estimated to be almost 5,500. By 2030, that number was predicted to rise by an additional 58,000. See GAO (2022).

of the recent past may be changing. In October 2023, NOAA’s Space Weather Prediction Center (SWPC) issued a revised prediction for solar activity during Solar Cycle 25, concluding that solar activity will increase more quickly and peak at a higher level than that predicted by an expert panel in December 2019.²

In a 2019 event hosted by the U.S. Chamber of Commerce and the SmallSat Alliance, keynote speaker Ajit Pai, then chair of the Federal Communications Commission (FCC), highlighted the importance of the space sector by stating, “Whether they know it or not, all companies will be space companies” (NSS 2019). Pai’s statement is notable given that global market sectors are shifting to rely heavily on technologies and services affected by space weather. The global space industry generated approximately $424 billion in economic activity in 2020, up 70 percent from 10 years earlier, and is projected to surpass $1 trillion by 2030 (Figure E-3). According to the U.S. Bureau of Economic Analysis (BEA), in 2021 the U.S. space economy had $211.6 billion of gross output and consisted of $129.9 billion or 0.6 percent of gross domestic product (GDP), implying that the U.S. space economy is about half of the global space economy. Additionally, the U.S. private space industry compensation was $51.1 billion with 360,000 private industry jobs.

Eventually, more debris will be created from these additional spacecraft unless timely reentry or transfer to a graveyard orbit can be ensured for each spacecraft. Therefore, now more than ever there is an increasing need to understand the risks, mitigations, and design environment, and a need to leverage future economic opportunities associated with the space environment. In the March 2023 NASA Cost and Benefit Analysis of Orbital Debris Remediation report (Colvin et al. 2023), the growing need for debris remediation is acknowledged and several methods of remediation are examined.

The government has been responding to the growing space weather needs through a wide variety of actions and organizational changes. Some examples are the formation of the Space Operations, Research, and Mitigation (SWORM) interagency working group designed to coordinate space weather activities, the Space Weather Advisory Group (SWAG), which is tasked to survey space weather end users and researchers and advise the SWORM on strategic priorities, and the National Academies of Sciences, Engineering, and Medicine’s Government-University-Commercial Roundtable on Space Weather to facilitate communication and knowledge transfer among Government

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² The 2019 panel, convened by NOAA, NASA, and the International Space Environment Services (ISES), produced the forecast. See NOAA Space Weather Prediction Center (2024).

participants in the SWORM Interagency Working Group, the academic community, and the commercial space weather sector. Space weather roles for specific branches of the government were clarified in the PROSWIFT Act;³ these have been supplemented by interagency memorandums of understanding and agreement (MOUs and MoAs).⁴ Also of note are the completion of space weather strategy and action plans (Weather.gov 2023; White House 2023), development of space weather benchmarks (NSTC 2018), the release of the NASA Moon-to-Mars (M2M) architecture plan (NASA 2023), and the publication of a comprehensive Space Weather Gap Analysis (NASA 2021). Roles and plans for the various agencies to address the urgent Space Traffic and Space Situational Awareness have also been established. Additional details with references to specific space weather agency documents, congressional acts, and executive branch orders and policies can be found in Annex E.A.

E.1.2 Definition of Terms

The term “space weather” refers to the physical state of the space environment and the solar and nonsolar phenomena that disturb it, but the term can also refer, somewhat ambiguously, to a domain within space science (Lilensten and Belehaki 2009; Morley 2020). Most often, space weather is practically understood as an applied science with a primary focus on its impact on human systems and technology near and on Earth (NASEM 2022),

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³ In October 2020, Congress passed the Promoting Research and Observations of Space Weather to Improve the Forecasting of Tomorrow Act (PROSWIFT Act; P.L. 116-181; 51 USC §§60601–60608). See https://www.congress.gov/bill/116th-congress/senate-bill/881.

⁴ Most recently, SolarNews, 2023, “QUAD Agency Memorandum of Understanding for R2O2R Signed,” December 14, https://solarnews.nso.edu/quad-agency-memorandum-of-understanding-for-r2o2r-signed.

although as human exploration expands, space weather at other locations of interest in the solar system (e.g., Mars) is rising in importance.

To prepare this report, the panel needed to have working definitions of two key terms: space weather science and space weather operations. The study of space weather and the steps needed to achieve a particular application required by end users (e.g., a forecast) have substantial overlap with the work done in the general field of space physics/heliophysics. While nowcasting and forecasting space weather is the purview of NOAA (NASA coordinates with NOAA as needed for exploration and off the Sun–Earth line mission support), space weather research is supported by multiple agencies, including NOAA, NASA, NSF, and DoD, as well as academia and the commercial sector.⁵

Separating space weather science from space physics/heliophysics is generally not simple, nor is the division completely agreed upon. The word “research” is itself used rather broadly to encompass a range of activities from fundamental to applied scientific research. The panel’s guidance for categorizing research activities is primarily driven by the motivation behind the work. While the majority of fundamental research for space science and space weather science may be the same, the incentives are typically different. Fundamental space science research can be driven purely by the desire to discover new phenomena and/or better understand the natural space environment, regardless of whether it may have an ultimate application to space weather. In contrast, space weather research is driven primarily by the need to improve the ability to characterize and predict the space environment with an end user application in mind.

In practice, for space weather science there ought to be a reasonably clear, straightforward pathway connecting the science to a specific potential end product or end user need. A good example of the dividing line between space science and space weather science research is seen by comparing the definitions of NOAA’s RL 1 (Readiness Level 1) and RL 2 (Figure E-4), with RL 1 being basic space science research and RL 2 being space weather science (NSTC [SWORM] 2022).

The term “space weather operations,” in analogy with tropospheric weather operations, refers to the activities and assets used to monitor, nowcast, and forecast the space environment phenomena that impact human activities and the impacts themselves. There is also a sub-branch of space weather operations that engages in emergency forensic analysis of satellite failures for the purpose of attributing failures to natural causes, component or system failure, or adversarial attack.

For many, especially in the forecasting community, the term “operations” implies continuous—24/7/365—fail-safe, real-time or near-real-time, data acquisition and analysis to create a time-critical product (e.g., a forecast or nowcast) that is used to inform actionable end user decisions. Others, especially consumers of space weather information, have a broader definition of space weather “operations” that includes data or products or applications that are used for long-term planning, mission design, anomaly attribution and forensic assessment, or mitigation strategies and best practices (e.g., “climatological” products and benchmarks). Furthermore, there are activities relating to the transition of scientific knowledge and understanding gained from space weather research to applications/tools, as well as the reverse with tool needs informing space weather research. While these non-time-critical activities may not in the strictest sense be clearly “operations,” neither are they fundamental space science research. They can be combined with operations into the larger term “space weather applications.”

In this report, the panel adopts the following working definitions:

• Space weather science involves systematic studies to gain the knowledge or understanding necessary to determine how a recognized and specific application for space weather operations and/or end users may be met. In other words, space weather science involves applied research directed primarily toward a specific, practical aim or objective relevant to space weather operations and end user needs. The research is undertaken either to determine possible practical applications for the findings of basic research or to determine new methods or ways of achieving specific and predetermined objectives. Space weather science falls largely in RL2 in the NOAA framework.

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⁵ This paragraph was modified after release of the report to accurately reflect space weather nowcasting and forecasting responsibilities.

• Space weather applications is a term that includes space weather operations, benchmarking, and climatological activities and work relating to the bidirectional connection between space weather science research and space weather tools. Specifically, space weather applications cater to all the needs and requirements of the space weather end user communities. Space weather applications fall largely in the RL3 to RL6 range in the NOAA framework.
• Space weather operations are a subset of applications, consisting of the activities and assets used to monitor, nowcast, forecast, and forensically reconstruct the space environment phenomena that impact operational systems (both human and technological) and activities and the impacts themselves. Operations are usually characterized by 24/7/365 staffing, real-time data streams, and fail-safe systems. Space weather operations fall largely in the RL7 to RL9 range in the NOAA framework.

models, the Federal Aviation Administration (FAA) Civil Aviation Research Institute-7 (FAA CARI-7) aviation radiation model, and NOAA/CU-CIRES (University of Colorado–Cooperative Institute for Research in Environmental Sciences) Whole Atmosphere Model–Ionosphere Plasmasphere Electrodynamics (WAM-IPE) coupled with the Global Forecast System (GFS) lower-atmosphere weather model.⁶ NOAA SWPC has also led an international effort to upgrade the space weather scales that reflect advancements in usage, impacts, and regional differences.⁷ To further accelerate the transition of research capabilities into operations, NOAA is establishing the Space Weather Prediction Testbed (SWPT; see NOAA SWPC 2022) to evaluate forecast tools and models and to bring together researchers, forecasters, and end users.

The 2020 Promoting Research and Observations of Space Weather to Improve the Forecasting of Tomorrow Act (PROSWIFT 2020) requires NOAA to sustain baseline space weather observing capabilities. As part of its response, NOAA reorganized its L1, GEO, and LEO space weather observing programs under a new National Environmental Satellite, Data, and Information Service (NESDIS) Office of Space Weather Observations (SWO) that is tasked with developing and deploying operational satellite systems for space weather monitoring. In 2025, NOAA will deploy the Space Weather Follow-On at L1 (SWFO-L1). SWFO-L1 will be launched as a rideshare with NASA’s Interstellar Mapping and Acceleration Probe (IMAP) mission, currently scheduled for launch in the second half of 2025. It will be equipped with solar wind plasma and magnetic field instruments to sustain in situ monitoring of the solar wind upstream of Earth, and with an operational coronagraph to remotely track coronal mass ejections (CMEs). An operational coronagraph is also included on NOAA’s Geostationary Operational Environmental Satellite-19 satellite (GOES-19), which launched in June 2024.

In the ionosphere–thermosphere–mesosphere (ITM) area, NOAA and the DoD/Air Force partnered with Taiwan’s National Space Organization (NSPO), University Corporation for Atmospheric Research (UCAR), NASA-JPL, and others to execute the Constellation Observing System for Meteorology Ionosphere and Climate (COSMIC-2) program. The COSMIC-2 satellites include a Tri-Global Navigation Satellite System (GNSS) RadioOccultation System (TGRS) for measuring ionospheric scintillation and atmospheric profiles, Ion Velocity Meter (IVM), and Radio Frequency Beacon (RFB). In addition, in 2022, NOAA awarded three Commercial Weather Data Pilot (CWDP) space weather contracts to commercial providers to provide near-real-time radio occultation (RO) measurements from GNSS receivers, and to evaluate of the quality and impact of that data on ionospheric forecast models. In fiscal year (FY) 2016, NOAA also began contributing approximately $1 million for the annual operations and maintenance of the ground-based Global Oscillation Network Group (GONG) solar observing network, which is operated by NSF for space weather monitoring.

The Abt Associates 2019 report Customer Needs and Requirements for Space Weather Products and Services report (Abt Associates 2019), conducted for NOAA, highlights user needs for the electrical power industry, satellite operators (see also Green et al. 2017), GNSS users, aviation, and emergency managers. Some common themes were the need for All Clear forecast (times of low activity), accessibility and usability of data and products, improved lead time, precision and granularity of data and forecasts, the availability of historical data products and forecasts, improved granularity of activity scales and geomagnetic indices, and education and outreach for both end users and researchers.

National Aeronautics and Space Administration

Since the 2013 decadal survey, NASA’s Heliophysics System Observatory (HSO) has increased to 19 operating missions with 13 more in various stages of development, all driving the fundamental research that is required for a better understanding of the Sun–Earth system. In response to the PROSWIFT Act, NASA established a Space Weather Program within the Heliophysics Division and recently selected the Space Weather Centers of Excellence (COEs) (NASA 2023). In collaboration with NOAA, NSF, and the DoD, NASA also established the Space Weather Research to Operations to Research (R2O2R) program to accelerate the transition of research to operations.

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⁶ See “Products and Data,” NOAA-NWS Space Weather Prediction Center, https://www.swpc.noaa.gov/products-and-data.

⁷ This paragraph was modified after release of the report to accurately reflect NOAA’s international efforts.

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⁸ Information about the workshops—Phase I (July 16–17 and September 9–11, 2020) and Phase II (April 11–14, 2022)—along with links to the workshop reports, are available at https://www.nationalacademies.org/our-work/space-weather-operations-and-research-infrastructure-workshop and https://www.nationalacademies.org/event/04-11-2022/space-weather-operations-and-research-infrastructure-workshop-phase-ii-workshop, respectively.

⁹ See https://www.nasa.gov/wp-content/uploads/2015/01/nasa_ussf_mou_21_sep_20.pdf.

versities and organizations in Argentina, and in countries in Africa. In addition, there has been an effort across the community to increase international collaboration with efforts like the International Space Weather Action Teams (ISWAT), which are community coordinated efforts hosted by the COSPAR Panel on Space Weather.

The United States has a long history of collaborating on space weather services with the European Space Agency (ESA). Space weather services in the ESA system are based on the federated ESA Space Weather Service Network (Figure E-6). The ESA federation represents a different approach to space weather services than in the United States.

The ESA network includes more than 50 expert groups in ESA Space Safety Programme (S2P) Participating States, carrying out data processing, space weather event analysis, risk assessment, and preoperational service provision. ESA is coordinating the work, development activities, and validation of new European space weather capabilities. All work at service layers beyond the data acquisition is outsourced to European institutes and to industry. ESA leads and coordinates the development of the space-based measurement systems that enable the services. For example, ESA is developing the Vigil mission to be launched in 2031 to add solar and in situ solar wind monitoring capability at the fifth Sun–Earth Lagrangian point (L5). ESA is also developing missions for monitoring of the auroral oval, radiation belts, plasma environment, and upper atmosphere by dedicated small missions and hosted payloads. A large fraction of the tasks in the data acquisition, particularly by ground-based observation systems, are carried out by industry or institutional partners in the Weather Service Network.

ESA is leading the analysis of the European ground-based space weather monitoring systems, initiating activities to fill gaps in the ground-based monitoring capability, and carrying out projects to demonstrate and mature utilization of data from new, operational ground-based assets. Space weather services from the ESA Space Weather Service Network are available from the service portal.¹⁰

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¹⁰ ESA Space Weather Service Network, “Current Space Weather,” https://swe.ssa.esa.int.

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¹¹ The acronyms and descriptions of energetic particle events vary. In space weather forecasting and space radiation operations, solar particle events (SPEs) refer to >10 MeV protons exceeding a threshold of 10 pfu. Energetic solar particle events (ESPEs) refer to >100 MeV protons exceeding 1 pfu. Last, energetic storm particles (ESPs) refer to the energetic particles produced locally at a shock as they travel in the heliosphere. Throughout this appendix, the most general term, solar energetic particle (SEP), will be used. SEPs are far more dynamic but less energetic than galactic cosmic rays, and they produce much of the space weather radiation that can be mitigated by, for example, the consideration of shielding options in the design of spacecraft and radiation shelters.

¹² This paragraph was modified after release of the report to clarify that the SWFO-L1 observatory is a rideshare on the IMAP mission.

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¹³ “High-Accuracy Satellite Drag Model (HASDM),” https://ccmc.gsfc.nasa.gov/static/files/SWW-2014-GEM-CEDAR-Bruce_Bowman_HASDM.pdf.

assets based on this information. Unfortunately, the 80–90 radar-tracked “calibration satellite” trajectories used for near-real-time correction of JB08 temperatures and densities are classified and not available for civilian research or independent operational conjunction assessment (see the section “Emerging Needs for Space Traffic Situational Awareness,” below). In addition, because JB08 models only a hydrostatic atmosphere, HASDM cannot accurately predict the rapid density changes associated with geomagnetic storms; the model essentially reverts to a nowcasting capability during the periods in which accurate forecasts are most needed.

At NOAA SWPC, a suite of ionospheric models is used in operations, as follows:

• The physics-based Coupled Thermosphere Ionosphere Plasmasphere Electrodynamics (CTIPe) model provides a global, time-dependent wind vector, temperature, and density of the neutral thermosphere and is used to issue a daily global total electron content (TEC) forecast.
• The Global Total Electron Content (GloTEC) global-scale 3D electron density data assimilation model nowcasts ionospheric conditions in near real time, assimilating ground-based GNSS observations from hundreds of dual frequency receivers around the world in real time as well as radio occultation (RO) observations from COSMIC. GloTEC is being used to evaluate commercial RO data as part of the Commercial Weather Data Pilot to improve geolocation of plasma irregularities and estimates of irregularity strength.
• The coupled WAM-IPE Forecast System (WFS; operationalized in 2021) provides a 2-day forecast of conditions in the ionosphere and thermosphere in response to solar, geomagnetic, and lower-atmospheric forcing. It supports SWPC advisories relating to communication systems and GNSS impacts and neutral density maps used for orbit prediction and space traffic coordination. Coupling WAM-IPE to the Geospace Model to obtain a more accurate conductivity map and to enable two-way magnetosphere–ionosphere coupling is the focus of one of NASA’s Space Weather COEs. The assimilation of COSMIC-2 high-rate ionospheric data into the WAM-IPE model to enable GNSS scintillation forecasts is a focus of another COE. Last, another COE is assimilating neutral-density data for thermospheric forecasting.
• The Oval Variation, Assessment, Tracking, Intensity, and Online Nowcasting (OVATION) model is an empirical model that uses L1 solar wind velocity and interplanetary magnetic field measurements to calculate a short-term (10- to 30-minute) forecast of the location and intensity of the aurora. OVATION provides an indication of current geomagnetic storm conditions and provides situational awareness for a number of technologies (GNSS/GPS, high-frequency [HF] communications). It is SWPC’s most viewed website, by far, owing to the desire of auroral tourists to gauge the location of the aurora on any given night.
• The D-Region Absorption Product (D-RAP) addresses the operational impact of the solar X-ray flux and SEP events on HF radio communication. It uses empirically determined relationships to compute HF absorption and the maximum useable HF frequency (MUF) from GOES satellite space weather data.

In the wider research community, the most advanced physics-based research model of the ITM system is the Whole Atmosphere Community Climate Model—Extended (WACCM-X), developed at the National Center for Atmospheric Research (NCAR) High-Altitude Observatory (HAO). WACCM-X has more advanced atmospheric chemistry and dynamic subroutines than WAM-IPE but lacks the integration of the tropospheric weather forecasting model that WAM-IPE uses for its lower boundary and initial conditions. WACCM-X is the preferred platform for the development of ITM data assimilation frameworks that may be transitioned to the WAM-IPE model for operational forecasting. Currently, HAO and the NASA Global Observations of the Limb and Disk (GOLD) team are working on the assimilation of GOLD global thermospheric temperature and composition data into WACCM-X. In DoD, the NAVGEM-HA (Navy Global Environmental Model—High Altitude) model developed at the Naval Research Laboratory (NRL) is the most advanced whole-atmosphere space weather forecasting model in operational use. NAVGEM-HA includes both tropospheric data assimilation as well as GOLD, ICON, DMSP, and meteor radar data assimilation in the middle to upper atmosphere. Additional empirical ITM models that are in both research and operational use are the NRL Mass Spectrometer Incoherent Scatter (NRLMSIS) model, the Drag Thermosphere Model (DTM), and the Storm Time Empirical Ionospheric Correction model.

nearer-term priority goals are grouped into two categories that indicate the relative priority of achieving each goal within the next 10 years:

• Critical: These goals are the highest priority for investment because their accomplishment would have the greatest impact across a wide range of space weather operations and services.
• Very Important: These goals are high-priority investments because their accomplishment would improve space weather operations and services significantly, typically for a select end user group.

Each goal is presented in bulleted text that provides a summary of

• The importance of the goal, including the end users that would primarily be impacted by its achievement.
• Current capabilities. (Note: Additional information on current capabilities is found in the section “Current State of Space Weather.”)
• What is needed to make significant progress on each goal.
• The factors considered in the priority categorization of the goal.

Goals within each category are not further ranked in terms of priority; listed order does not imply higher priority for goals within each category.

Some of the panel’s goals include a specific forecast time horizon (also called “lead time”) target, while others are more general capability goals. When a definitive lead time is displayed, it reflects the panel’s opinion of the capability that can be realistically achieved with high accuracy and reliability within the next decade. For example, the solar eruption forecast goal has a specific lead time target of 12 hours and the associated SEP event lead time of 6 hours.

The panel understands that there are currently several eruption forecasts with 24-, 48-, and even 72-hour lead times and that some end users (e.g., power grid operators) would ideally like forecasts of geoeffective eruptions with more than 30 hours of lead time. However, the panel believes that the current long lead time forecasts are not accurate or reliable enough to meet end user requirements; decreasing forecast lead time is the clearest route to improving accuracy and reliability in a complex environment. Furthermore, certain end user needs may prove unattainable given the anticipated advancements in knowledge over the next decade—for example, the ability to monitor, model, and forecast active region evolution accurately over more than 30 hours is unlikely to be achievable in the next decade. To reiterate: When the panel specifies a lead time, it indicates the belief that the target can be achieved with high accuracy and reliability within the next 10 years.

E.3.1 Goal 1

Develop an accurate and reliable 12-hour lead time probabilistic >M1 solar eruption forecast and associated SEP event forecast with 6-hour lead time.

Solar magnetic eruptions are the root cause phenomenon behind extreme and life-threatening space weather events. They are the progenitors of solar flares that cause ionospheric disturbances, CMEs that cause geomagnetic storms and associated thermospheric and ionospheric impacts, and SEP events that can damage or disable satellites and spacecraft and threaten the long- and short-term health of astronauts in worst-case scenarios.

While solar wind HSS and associated CIRs are capable of producing strong (G3 on the NOAA scale) and even sometimes severe (G4) events, the only phenomena capable of generating the 1-in-100-year extreme geomagnetic and/or radiation storms are solar magnetic eruptions. Significantly increasing lead times to enable mitigation of a number of space weather impacts (e.g., communications and navigation interference, power grid destabilization, astronaut health) is predicated on better understanding and forecasting of the timing, direction, and intensity of solar eruptions. The most energetic Earth-directed CMEs can arrive within 12–14 hours, within the error bars of arrival time estimates from current solar wind/CME models. Major SEP events can also penetrate Earth’s magnetic field to impact aviation and commercial suborbital operations outside of polar regions.

Currently, SWPC issues 24-, 48-, and 72-hour probabilistic eruption forecasts based on analysis of solar active region morphology, climatological rates, and human-in-the-loop (HITL) modifications with magnitudes based

on the associated X-ray flare magnitude, specifically for events with >M1 flares on the NOAA X-ray flare scale. The 24-hour eruption/flare forecasts have been shown to have true skill statistic (TSS) scores of no better than 0.4–0.5 owing to a high false alarm ratio (FAR) that results in low reliability and leads users to ignore these forecasts when making decisions. Automated 24-hour solar eruption forecasts based on statistical and ML techniques currently do no better than HITL forecasts. Skill at 48- and 72-hour lead times has not been analyzed in detail in open literature but is thought to be no better than random prediction because the timescales of active region evolution to eruptive states are on the order of 24–30 hours, significantly less than either lead time. The panel is not aware of any end users who use these forecasts to decide on actions to mitigate the potential consequences of a major solar eruption.

SWPC also issues 24-, 48-, and 72-hour probabilistic forecasts for S1 proton events, defined as ≥10 particle flux units (pfu) for ≥10 MeV protons, with a 24-hour probability of detection (POD) of 0.5–0.7 and declining skill for days 2 (48 hours) and 3 (72 hours). Short-term SEP event warning products have lower lead times of around 10 to 30 minutes (for ≥100 MeV protons) to 1–1.5 hours (for ≥10 MeV protons) but again a relatively high FAR of ~25–40 percent. Some post-eruptive empirical SEP models achieve similar skill with median lead times of up to 2 hours but are not yet fully validated or transitioned into operations.

For many prompt SEP events, increasing the lead time to more than a few hours will allow unprotected astronauts on the lunar surface or in unshielded deep-space environments to retreat earlier to shielded environments resulting in reduced overall accumulated dose. The NASA Moon to Mars Space Weather Analysis Office has worked with the SRAG and the CCMC to deploy more than six research models running in real time, providing outputs for the SEP Scoreboards at NASA and for M2M analysis during Artemis missions. The University of Malaga Solar Energetic Particles (UMASEP) proton forecasting model is currently being evaluated for possible transition to the Space Weather Testbed at NOAA/SWPC.

To achieve realistically actionable lead times, which are required across multiple end user groups, additional progress will be needed in the production of an accurate and reliable probabilistic solar eruption watch product and associated eruption magnitude forecast. Accurate (very high POD) and reliable (very low FAR; near zero Brier Score) forecasts of the occurrence of large solar eruptions (≥M1 flares) will safeguard most (if not, all) of the activities impacted by space weather. As mentioned, solar active regions can evolve to eruptive states on timescales of 24–30 hours. The panel believes that an accurate and reliable 24-hour flare forecast is therefore likely not achievable within the next 10 years as it would require the development of data assimilative solar active region models incorporating near-real-time chromospheric and coronal magnetic field measurements in addition to the lower photospheric–magnetic boundary conditions. Such measurements do not yet exist even in the research realm. However, experiments with machine learning solar eruption models have shown an optimal skill level for forecast lead times between about 6 and 18 hours (Chen et al. 2019). Based on this, an accurate and reliable, data-driven (e.g., using EUV chromospheric and coronal imaging), 12-hour eruption forecast is likely achievable, given sufficient investment.

Lead times on SEP event forecasts do not need to be as long to allow actionable mitigation strategies for astronaut safety, launch go/no-go assessments, and aviation route planning (see also Goal 12) to be put in place. The panel believes that an accurate and reliable 6-hour forecast, particularly for the 100 MeV and above proton energies, is an achievable and meaningful advance that can, with sufficient investment, be realized in the next 10 years. A primary measurement requirement to achieve these lead time, accuracy, and reliability milestones via advanced data-driven or data-assimilative approaches is simultaneous, intercalibrated, full-Sun measurements—including from polar vantage points—of magnetic field and atmospheric structure along with coronagraphic imaging so that active regions can be tracked over their entire lifetime, magnetic connectivity established over longitudinal spans, background solar wind models improved, and CME trajectories relative to surrounding coronal structure established. Intercalibrated means that measured magnetogram flux density values and uncertainties can be linearly calibrated across any pair of observing platforms at resolutions sufficient to feed advanced prediction models. Experience with the GONG magnetogram intercalibration efforts has shown that, at minimum, identical instrumentation, spectral line choice, and data reduction algorithms are required for this condition to be met.

Taking into account the fundamental role of solar magnetic eruptions in driving the most impactful space weather, the large number and degree of impacts posed by SEPs, the significant modeling efforts that have already been made toward this aim, and the high likelihood of making breakthrough progress given sufficient investment, the panel assesses that it is critical to achieve this goal within the next decade.

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¹⁴ Orion Space Solutions is now part of Arcfield. See Erwin (2023).

open literature. Of the physics-based models in existence, only WAM-IPE has been integrated into operational use at NOAA/SWPC to provide thermospheric density forecasts to LEO satellite operators. But WAM-IPE has not been validated, and without data assimilation to correct it, the model, like all large physics-based numerical simulation models lacking data assimilation, is inaccurate even during quiet conditions.

Accurately calculating satellite trajectories to ensure safe operations in LEO requires more than just a good thermospheric density model; it also requires accurate calculations of the coefficient of drag (Cd) of satellites and debris objects, detailed knowledge of satellite geometry and attitude relative to the ambient neutral winds in LEO, and solar radiative forcing, particularly for higher LEO altitudes. Calculations of Cd in turn require detailed knowledge of a given satellite or debris object’s geometry and materials, atmospheric composition as a function of altitude and energy inputs, and the gas–surface interactions that underlie drag forces in orbit. Current operational trajectory models often assume constant Cd values based on simplified spherical geometries.

There is a critical need to develop an accurate and reliable thermospheric-density model that incorporates advanced data assimilation capabilities and produces a 24- to 48-hour forecast of thermospheric density during geomagnetic storm conditions. Such a model cannot be an empirical hydrostatic model owing to the need for accurate predictions during dynamic storm conditions. Global measurements across a large range of spatial and temporal scales are needed to better understand how solar and magnetospheric inputs combine to drive upper atmospheric dynamics during storms. Moreover, there is still a lack of sufficient measurements to understand how the lower atmosphere (troposphere/stratosphere) and mesosphere condition the upper atmosphere—for example, by the coupling of gravity waves to thermospheric dynamics.

The development of advanced data assimilation techniques that can operate in the data-sparse upper atmospheric regions will also be critical to meeting this goal. In particular, data assimilation systems developed for the data-rich lower atmosphere, such as the well-known 4DVar system, are in general not directly transferable to the highly driven upper atmospheric regions with sparse measurement distributions. Significant investments are needed in a variety of novel data assimilation research programs, including investigations of nonlinear and non-Gaussian ML methods for model parameter and state space adjustments. It has also been shown that data assimilation systems concentrating on ionosphere or thermosphere data sources separately do not produce accurate state vector convergence; a coupled ionosphere–thermosphere system requires coupled ionosphere–thermosphere data assimilation for accurate convergence. In addition, more environmental measurements are needed in the LEO regime at a variety of altitudes and orbital inclinations. For example, a radar tracking calibration satellite fleet like that used for HASDM but designed specifically for civil applications would be beneficial. Last, research into gas–surface interactions and measurements to improve our knowledge of drag forces and Cd calculations is needed so that accurate satellite force models can be deployed.

In summary, the accomplishment of this goal will require an integrated modeling framework that includes the following:

• A data assimilative upper atmospheric forecasting model that is accurate during geomagnetic storms and includes quantified uncertainties that are much lower than current model uncertainties;
• An advanced satellite forcing model that accurately calculates nonconservative drag and solar radiation forces, taking into account Cd and frontal area variation over entire orbits; and
• Improved conjunction assessment calculations and visualization systems that will enable operators to better analyze the increasingly congested LEO environment and make rapid decisions during dynamic conditions such as extreme geomagnetic storms.

It is recognized that only the first of these items is directly related to space weather research; however, the panel includes them to highlight that space weather research must often be closely integrated with other applied science and engineering disciplines to achieve actionable results for end users.

Because of the increasing congestion of the LEO orbital environment, potential for catastrophic damage to increasingly critical space infrastructure, and the central role played by thermospheric neutral-density forecasts in determining LEO resident space object trajectories, conjunctions, debris propagation, and reentry parameters, the panel assesses that it is critical to achieve this goal within the next decade.

risks at locations of interest would support a human presence in cislunar space. Note that the panel’s discussion of the requirements for science and monitoring of the Martian environment, and during Earth–Mars transit, is presented in Section E.5, “Long-Term Goals.”

NASA’s Artemis program is under way, with humans slated to return to the Moon in 2026. Commercial companies are already planning for lunar tourism and will continue to broaden these efforts. Because of the current and continuing expansion of human presence in cislunar space, the panel assesses that it is critical to achieve this goal within the next decade.

E.3.4 Goal 4

Develop a 12-hour lead time forecast of CME Bz and a 2- to 3-hour upwind nowcast of other solar wind and CME characteristics at Earth.

The North–South component of the magnetic field of the solar wind and CMEs (so-called Bz) is the main determinant of the severity of geomagnetic storms when these structures impact Earth. Forecasting Bz, particularly for fast incoming CMEs, is critical to support a wide range of end users such as power grid operators and satellite operators, and for input to various magnetospheric, ionospheric, and auroral models and geomagnetic index (Kp, AE, PC, Dst) forecasts that are used in impact models. The dawn-to-dusk electric field, given approximately by the product of Vx (the CME/solar wind velocity in the x direction, where x is in the Sun–Earth [radial] direction) and Bz, is the main driver for dayside magnetospheric reconnection rate that largely determines storm severity. Vx and Bz are therefore the most important solar wind or CME quantities to measure to predict the degree of solar wind–magnetosphere coupling upon impact.

While some end users request a 24-hour Bz/geomagnetic storm severity forecast, the panel feels that this is not achievable with the observations and models planned for the coming decade. In particular, the fastest CMEs that cause the most severe storms can arrive in less than 15 hours. However, the panel believes that an accurate and reliable forecast of Bz sign and magnitude with a 12-hour lead time, accompanied by upstream measurements of CME Bz that afford a 2–3 hour nowcast/warning capability, is achievable in the next decade. Other solar wind parameters, such as velocity and proton density, are also important to determine the full response of the magnetosphere to impact, but they are less critical as forecasting targets.

Currently, forecasting IMF Bz and solar wind parameters at Earth relies primarily on solar wind measurements at the L1 Lagrangian point, which is approximately 1.5 million km sunward of Earth (1 percent of the Earth–Sun distance or 0.99 AU). Such measurements provide a less than 1-hour short-term forecast; for the fastest and most dangerous CMEs, the warning time can be only about 10 minutes. These lead times are insufficient for any operators to take meaningful mitigating actions and are analogous to giving a 30-minute lead time on hurricane arrival to a coastal community.

For CMEs, the radial speed (and hence approximate arrival time at Earth) can be estimated from remote coronagraph observations with an accuracy of about ±100–150 km/s on a range of about 500–3,000 km/sec. Other parameters such as CME magnetic field magnitude and direction are not currently modeled in operations. For example, the operational WSA/Enlil model does not include CME magnetic field; CMEs are modeled only as hydrodynamic perturbations on the background solar wind. Although the panel knows of no definitive validations of WSA/Enlil CME Vx speed predictions, the model seems to generally underpredict Vx speeds with mean absolute errors (MAEs) of no less than 30–40 percent. SWPC issues geomagnetic storm watches with severity estimated on the G-scale based on coronagraph data that indicate the possibility of CME impact at Earth. But without magnetic field information, the severity of the storm is rarely accurately predicted and gross underpredictions of magnitude (e.g., G4 storms occurring when only a G1 was forecast) are common. The probability of detection of current NOAA/SWPC geomagnetic storm forecasts of magnitude “G1 or greater” is about 40 percent and the FAR is about 75 percent (from GPRA reports), making the forecasts essentially unusable for actionable decision-making. The main reason for the low accuracy and low reliability of current geomagnetic storm severity forecasts is inaccurate Earth-directed speed (Vx) predictions and the lack of Bz prediction by any forecast model.

the revisit times are infrequent and a comprehensive picture of full auroral oval dynamics cannot be synthesized from these observations.

The United States currently lacks an operating, full-hemisphere auroral imaging mission, a situation that has persisted since the termination of NASA’s Global Geospace Science (GGS) Polar satellite in April 2008. The joint ESA/China Solar Wind Magnetosphere Ionosphere Link Explorer (SMILE) mission due to launch in 2025 includes the ultraviolet imager instrument (UVI), which will obtain full oval views in the ultraviolet from its planned Molniya orbit, but the availability of UVI data for use by U.S. agencies is in question owing to current legal bans on interactions with Chinese government agencies.

To meet the needs of critical infrastructure operators, real-time information derived from actual auroral imaging is necessary. Both next-generation ground-based all-sky imaging systems as well as space-based multispectral imaging systems are needed to provide sufficient coverage and geolocation accuracies for end users. Unlike current models, which operate on a regional scale, high-resolution (10 km scale) auroral imaging can simultaneously offer a comprehensive snapshot of the entire hemisphere with mesoscale structure resolution, providing high-reliability data about auroral properties and dynamics during geomagnetic storms.

In addition, in situ suprathermal to energetic particle measurements from polar-orbiting LEO satellites are needed to inform particle precipitation rates in ionospheric models. Improvements in polar cap potential specification through the extension of radar systems such as Super Dual Auroral Radar Network (SuperDARN), as well as the continuation of the critical field-aligned current measurements in LEO currently made by the Active Magnetosphere and Planetary Electrodynamics Response Experiment (AMPERE) system, are also needed. Sustained funding is also necessary to support applied research into advanced models for auroral activity and its effects on the ionosphere–thermosphere systems and satellites in LEO. By specifying how impacts relate to these properties, the information becomes actionable and robust for decision-making that can compile training sets for supervised ML models that could potentially supplant computationally heavy and slow physics-based models for ionospheric impact forecasting.

Because of the increasing congestion of the LEO orbital environment and the critical role played by auroral activity in a number of space weather effects and hazards (including GICs, spacecraft charging, and ionospheric and thermospheric disturbances), the panel assesses that it is very important to achieve this goal within the next decade.

E.3.6 Goal 6

Develop reliable probabilistic All Clear forecasts with multiday lead time.

An All Clear forecast indicates that the space weather environment will be quiet, clear, or nonthreatening for a predetermined time period (e.g., 12 or 24 hours). These forecasts are typically issued following major events such as an SEP-causing eruption to indicate the end of the associated threats to human or technological systems. The challenge in issuing an All Clear forecast comes during high solar activity, when there can be multiple eruptions per day. How does one ensure that none of these eruptions cause subsequent geomagnetic storms or SEP events in the direction of critical space operations within a multiday period?

All Clear will have different definitions for different phenomena and end users, but there would be a benefit from an accurate and reliable probabilistic forecast that a given phenomenon will very likely not occur in a specific time window at a specific location. End users in all fields related to space weather could benefit from such a forecast, including human spaceflight, aviation/ATC, power grid operators, satellite operators, RF communications users, OTHR operators, and GNSS users.

The current capabilities for All Clear forecasts are limited. ESA issues a human-in-the-loop All Quiet forecast that is based on the prediction that no Earth-directed eruptions or solar wind disturbances will occur in the specified period. The panel is aware of some models that produce All Clear forecasts—for example, on the All Clear and Probability SEP Scoreboards; however, their skill is currently being assessed. While SEPs are the obvious and necessary initial focus for All Clear development, individual users have needs for All Clear forecasts for nearly every phenomenon. It is worth noting that SWPC does not issue an All Clear forecast of any kind in keeping with National Weather Service (NWS) policy. For example, there is no such thing as an “All Clear tornado forecast” or an “All Clear hurricane forecast” because of the potentially catastrophic consequences of a false negative and

associated large legal liabilities. Given the realities of the U.S. legal landscape, it is likely that only the operators of critical mission equipment or human spaceflight missions themselves will be willing to risk issuing All Clear forecasts during active periods of the solar cycle. For example, NASA will likely issue nonpublic All Clear SEP forecasts for use only by NASA human spaceflight missions.

Because All Clear could potentially be applied to all fields of space weather, improvements in essentially all space weather observations and models are desirable to achieve this goal, including coronagraph imagery, X rays, EUV, in situ solar wind plasma, magnetic fields, and energetic particles. From a measurement perspective, continuous full-Sun observations to provide the complete instantaneous state of the Sun to identify solar conditions relevant to All Clear forecasting would be highly beneficial to achieving this goal. In addition, solar radio monitoring for detection of CME-related radio signatures, SEP flux measurements from multiple vantage points around the Sun, solar wind observations upwind of the L1 Lagrangian point, and continuous monitoring of the geospace environment to establish the relevant internal drivers and response states are needed.

Because of NASA’s increasing interest in All Clear SEP forecasts as astronauts return to deep-space travel and the broad benefit that reliable All Clear space weather forecasts would have for a wide range of end users, the panel assesses that it is very important to achieve this goal within the next decade.

E.3.7 Goal 7

Develop reliable probabilistic forecasting (1 hour) of the geoelectric field with increased spatial resolution (200 km).

The geoelectric field is an important driver of impacts to long-line conducting infrastructure at Earth’s surface. The primary impact is power transmission networks which are a critical national infrastructure, but pipelines, undersea cables, railways, and other long conductors can also be impacted. Currents induced in power transmission systems can lead to reduced lifespan (or failure) of transformers and voltage instability and collapse of the network on regional scales. In all cases, the spatiotemporal structure and magnitude of geoelectric field determines critical properties of the network impacts, and thus space weather impacts can be detrimental and in severe cases debilitating to operational systems.

The current NOAA/SWPC Geoelectric Field Models provide deterministic nowcasting based on a geographically sparse set of magnetometer measurements. The model has not been validated, and it is not known to this panel whether any grid operators rely on the model for actionable decision-making. The Geospace configuration of the SWMF in operation at SWPC produces short lead time (15–30 minutes) deterministic predictions of ground magnetic perturbations. This model is also not validated and is known to exhibit significant bias in storm-time geomagnetic perturbation magnitudes. A proof-of-concept study to couple the Geospace and Geoelectric models is being carried out at SWPC but is not currently used operationally for geoelectric field prediction. Until the known biases of the Geospace model are corrected, any geoelectric forecasts based on this model will not be accurate and will likely not be adopted by end users. The ML model of Dst produces a longer lead time (6 hours) forecast with quantified uncertainty and exhibits significantly less bias than the Geospace model.

The relevant nowcast and forecast capabilities need increased spatial resolution to better characterize regional impacts for operators. Meeting this basic need will require a number of basic research components that are detailed in Table E-1. From an applied research perspective, the national magnetotelluric survey needs to be completed with quantified uncertainty established for the transfer function and a similar survey for the U.S.–Canada border region needs to be undertaken to ensure that there is adequate coverage for full-CONUS modeling of the geoelectric field. In addition, the development of probabilistic forecasting models needs to be undertaken with the involvement of grid operators to ensure that the models are accurate, reliable, and thus actionable from an end user standpoint. Direct measurements of the geoelectric field are also needed for model development and validation. Operationally, the magnetometer network across CONUS and Alaska needs to be significantly enhanced to provide regional-scale (100 km) data that can be used in data-driven model development and validation of current and future forecasting models.

Because GIC impacts to the electric power grid and other critical infrastructure are one of the most consequential effects of space weather on a societal scale, and because the current capabilities are not optimally serving a key end user community, the panel assesses that it is very important to achieve this goal within the next decade.

works, employing a variety of methods, during the solar minimum period preceding a given cycle. The capability to update the prediction based on the functional form of the consensus model, with peak timing and amplitude adjusted to match observed sunspot number progression in the cycle, was recently released by NOAA.

Shorter-term 45-, 27-, and 3-day F10.7 forecasts from SWPC currently use recurrence and forecaster augmentations for ARs rotating on/off the disk; LEO satellite operators use them to predict drag conditions and hence orbital trajectories. There is also the “Schatten model,” which issues a sunspot number prediction several solar cycles into the future. Alarmingly, this model, which has been demonstrated to have extremely low-skill prediction, and crude thermospheric density models tied to the sunspot predictions, are being used by satellite operators to calculate expected mission lifetime and reentry dates for LEO satellites. This illustrates the maxim that end users will “use whatever they can get” when trying to make important decisions that depend on estimating future space environment conditions.

Current predictive capabilities are hampered by a limited understanding of the solar polar magnetic field and surface and the subsurface flows that are believed to play a key role in the dynamo generation of magnetic flux in each cycle. Better dynamo models based on measured surface and subsurface global-scale flows in the polar regions are needed, as well as simultaneous observations of all solar longitudes, to enable observation of all eruptions, not just the ones on the Earth-facing disk. The measurement need can be met by developing full-Sun observing systems that include both magnetic field and helioseismic observations to measure surface and subsurface magnetic structures and associated flows. There is also a need to study the relationship between sunspot number and solar activity of interest and to move to a long-term prediction of impactful phenomena related to sunspot activity. To address the satellite operator mission design requirements, there is a need to develop multicycle predictions that are at least marginally accurate and have associated quantified uncertainties.

Because the solar magnetic cycle is the primary origin of space climate variability, and because the current one-time full-cycle-length forecasts do not provide reliable and accurate, and therefore actionable, information to mission planners, satellite operators, and other key end users, the panel assesses that it is very important to achieve this goal within the next decade.

E.3.10 Goal 10

Develop a robust reanalysis capability¹⁵ for forecast/nowcast models with established community standard input data sets for all key space weather drivers and impacts.

Reanalysis refers to the process of creating a long-term reconstruction of the state space in the space weather environment, typically, but not exclusively, generated with data-assimilative numerical simulation models. End users of this process include satellite/vehicle anomaly analysts and designers, who use reanalysis to refine data from the past that determine either specific conditions during a past or ongoing mission or to establish cumulative and worst-case transient design environments. Reanalysis is also a key process in improving forecasting models—for example, when new data sources become available, errors in observations are identified and corrected, or potential model improvements need to be validated. Furthermore, it is likely that the reanalysis period will include challenging events and thus illuminate model performance gains (or losses).

Reanalysis is a mainstay activity in tropospheric weather forecast model development. For example, the NASA Modern-Era Retrospective Analysis for Research and Applications, Version 2 (MERRA-2) (Bosilovich et al. 2024) is a large weather model output database containing atmospheric parameters from 1980 to the present that have been improved by inclusion of recent NASA satellite observations assimilated into a numerical prediction model. In space weather, the closest analog to tropospheric reanalysis is limited to a handful of papers reporting long-term numerical simulations, usually not data assimilative, and some studies that involved simulating every storm during a long time interval. Such “free running” simulations without data assimilation would not generally be recognized as reanalysis runs by tropospheric weather researchers because they do not include improved input data or specific model improvements demonstrating superior state space specification.

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¹⁵ The capability should be robust in the sense that it is not dependent on a small group’s effort to create and maintain but rather is spread across several groups that are well funded through standard mechanisms.

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¹⁶ This paragraph was modified after release of the report to clarify SEP exposure among airline crew members.

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¹⁷ “National security space (NSS) launches support the military and intelligence community.” See Sayler (2023).

3. The panel suggests that relevant agencies coordinate to develop and maintain key space weather observations used in operations. For example,
   • GONG, and its potential upgrade, ngGONG¹⁸ (next-generation GONG), are to provide pixel velocity, intensity, and magnetic-flux images of the Sun.
   • The Radio Solar Telescope Network (RSTN), and its modernization, are to provide observations of solar radio bursts.
   • The addition of a U.S.-based antenna capable of monitoring solar radio flux at 10.7 cm that has a long track record as a proxy of solar activity.
   • Neutron monitor networks, which provide observations of high-energy particles striking Earth’s atmosphere, are needed during ground-level enhancements to assess their intensity and geographic extent.
   • The expansion of ground-based magnetometer networks that measure magnetic field perturbations that can impact the power grid.
   • Ionosondes that provide observations to support nowcasts for HF communication impacts during, for example, post-storm MUF depressions.
4. The panel suggests that vested agencies and departments continue to establish structure and funding for the space weather testbed to facilitate formal, two-way engagement between the space weather research and operations communities and space weather end users in impacted industries and sectors (in agreement with SWAGF&R23 R.13.1). This is required to understand and qualify end users needs and for the development and prioritization of improved space weather applications and operational nowcasting and forecasting products.
5. The panel suggests that SWORM agencies work to understand the economic impacts and evolving risk to infrastructure from space weather impacts, for the determination and prioritization of new space weather products and services (in accordance with the 2019 National Space Weather Strategy and Action Plan and recommendations in the SWAGF&R23, Chapters 7 and 8). In partnership with end users, new space weather benchmarks, scales, and metrics need to be developed (SWAGF&R23, Chapter 6).
6. The panel suggests that SWORM ensure that the quad-agency Space Weather Research to Operations to Research (R2O2R) program, which is currently managed by NASA, NOAA, NSF, and DoD, is adequately funded. In addition, the panel suggests that the scope of any R2O2R program focus clearly on the development of forecasting and nowcasting models and/or validation, as well as forensic reconstructions, that are required to meet identified user needs. The panel suggests that both the O2R and R2O portions of the R2O2R program bridge basic and applied research, space weather science, and OSSE and OSE development and testing, and that the development and testing of new, pathfinder observatory systems are adequately funded between the agencies. The panel strongly suggests that any expansion of the R2O2R program at NASA be funded through an augmentation of the NASA Heliophysics budget and not at the cost of fewer heliophysics science missions or a reduced R&A budget and portfolio.
7. The panel suggests that sufficient and sustainable funding schemes are created for the final transition of models and instrumentation/observatories to relevant operational offices with support for validation and training. In addition, the panel suggests that SWORM ensure that there is a smooth transition as model development moves between agencies and from one RL to another. The panel suggests that funding schemes and memoranda of understanding are put in place for the R2O transition of instrumentation, sensors, or observatories (whether ground-based or space-based), with a clear definition of the roles of instrumentation, science, and operational teams as well as support for continuing calibration and validation. (See Figure E-8 for a conceptual development chain for new operational observatories.)

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¹⁸ The National Solar Observatory (NSO), which is operated by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with the National Science Foundation Division of Astronomical Sciences, is “promoting the definition and design of the Next Generation Global Oscillations Network Group (ngGONG).” See “NgGONG—NSO—National Solar Observatory,” at https://nso.edu/telescopes/nggong. The entity or entities that would manage ngGONG operations have not been determined. (See the following for suggestions from the Panel on Space Weather Science and Applications.)

8. The panel suggests that vested agencies and departments expand and sustain space weather research “proving grounds” in government, academic, and commercial environments (in accordance with SWAGR&F23 R.13.1), and increase the scope and activity of government “testbeds” for validating and transitioning research products to operations.
9. The panel suggests that space weather–focused programs specifically support the enabling of probabilistic hazard assessment and state prediction across the priority goals. Uncertainty quantification and probabilistic modeling are key components of providing actionable information to end users. Standard approaches generating probability distributions express uncertainty but may not translate to allow the uncertainty to be used in assessing impacts. Many space weather hazards are driven by spatiotemporally dynamic structures and systems, and the physical domains of space weather exhibit hysteresis in their evolution. In physical domains that are impacted by these considerations, data assimilative and/or ensemble methods using multiple realizations of the hazard environment may be required to appropriately quantify errors and characterize the uncertainty in hazard to the end user.
10. The panel suggests that agencies involved with space weather develop a dedicated on-orbit communications relay network, standard protocol, and dedicated global ground station network to enable and allow for very low latency space weather data streams. Currently, reliance on the Deep Space Network is a major bottleneck and barricade, and assets in LEO (and elsewhere near Earth) are often unavailable to provide real-time data streams owing to a lack of space-based relay and/or ground station access. Space weather measurements in the upcoming decades will certainly include remote observations from distant platforms (e.g., but not limited to the Sun–Earth Lagrangian points L4 and L5 and the Sun–Mars Lagrangian L1), as well as from large orbital constellations in Earth and solar orbits. The panel is concerned that existing communication networks and stations will not be sufficient to address future space weather needs and requirements.
11. The panel suggests that funding agencies encourage and support the establishment of heliophysics departments in major research universities with support for faculty positions in the applied science of space weather, forecasting/predictive systems research, and data science as well as multidisciplinary solar and space physics research. The current siloed approach and the lack of a unified name for our field of research have produced independent solar, geomagnetic, and ionosphere/thermosphere experts who lack the system- and predictive-science knowledge and skills to significantly advance space weather as a field.
12. The panel suggests that vested agencies and departments establish and sustain professional workforce development programs in space weather operations and applications development, in agreement with SWAGR&F23 R.13.6. This will enable professionals in space weather forecasting, engineering development, and policy (i.e., critical workers in space weather outside of the traditional research fields) to increase their knowledge base and improve national preparedness for extreme space weather events.

Structural Suggestions to the NASA Space Weather Program

The panel suggests that the NASA Space Weather Program take the following actions.

1. Develop a dedicated mission line in the new Space Weather Program called the Space Weather Explorers (SWEx) and include in this line mission of opportunity (MO) flights.

Missions proposed to the SWEx program could be either space weather research pathfinders for future space weather operational missions or missions taking measurements that close known space weather observational data gaps hindering space weather research. Pathfinders could be in terms of technology demonstrations (e.g., solar sail, propulsion, new observational technology) needed for future space weather platforms, instrumentation (e.g., miniaturized particle instruments), or pathfinding demonstrations (new orbits, new capabilities) to intentionally develop new data sets that can be used for OSEs. Data from such SWEx pathfinders will be useful to transition from OSSEs (i.e., mission concept validation) to OSEs (i.e., new operational observatory validation).

The panel suggests that programs take advantage of rideshare opportunities made possible by ESPA and propulsive-ESPA rings, especially with NOAA (and other) launches to geosynchronous orbit, the Sun–Earth

Lagrangian L1 point, and polar low Earth orbit (LEO), as well as launches associated with the rapid, frequent deployment of new assets into proliferated LEO, the Moon to Mars (M2M) program, and planetary missions to Mars, Venus, Mercury and near Earth objects. For examples of strategic and targeted space weather observational gaps that can be filled with new observatories via the new SWEx mission line, MOs, and/or rideshare opportunities, see Figure E-9(a–c).

The panel strongly suggests that the new Space Weather Program be funded through an augmentation of the NASA Heliophysics budget and not come at the cost of fewer Heliophysics Science Explorers or a reduced research budget and portfolio.

• Plasma, energetic particles, and magnetic field measurements from the cislunar magnetotail region (Goal 3).
• Measurements of thermospheric interaction with a drag test object in LEO (Goal 2).
• Dedicated instrument suites for characterization and real-time knowledge of the space weather environment on the lunar surface (Goal 3).
• Other measurements as described in the NASA Space Weather Gap Analysis—for example, solar wind and magnetic field measurements from peri-geospace.

2. Include a Space Weather Enhancement Option (SWxEO) to the suggested Heliophysics Explorers line, LWS, and STP mission proposals that is reviewed as part of the concept study review (CSR) at the end of Phase A and becomes one of the aspects taken into consideration for down-selection.

This echoes Recommendation R.10.3 in the SWAGF&R23. The desired multipoint measurements relevant to space weather can be provided by a combination of SWEx and augmentations on science missions through SWxEOs. Augmentation from SWxEOs is best thought of as being based on orbits and observables (measurements, availability of data in real time, etc.) independent of the science objectives of the mission.

3. Develop global full-Sun science measurements (360-degree longitudinal and polar region coverage) of the solar photosphere and outer atmosphere, with magnetic field, outer atmosphere, and corona imaging and in situ energetic particle measurements.

Several priority goals (e.g., Goals 1, 3, 4, 5, 6, and 9) would be significantly advanced, both in their research and operational components, by the availability of continuous, simultaneous, intercalibrated, full-Sun

measurements that include both equatorial and polar regions. The capability to view all longitudes of the Sun and the polar regions simultaneously will enhance our ability to develop more advanced predictive models of how solar active regions evolve and erupt and advance fundamental research concerning how the polar magnetic field influences the solar wind and dynamo. Given the demonstrated challenges calibrating identical sensors for GONG, the panel feels there is great risk in merely coordinated observations of the solar magnetic field from the equatorial and polar regions. A unified measurement system using identical magnetograph instruments is viewed as the most worthwhile implementation.

4. Ensure that all models and databases developed and maintained under government funding for space weather research or operations are open source and in user-friendly formats.

While it is noted that a private entity that funds the development of a model or tool through its own capital has the right to restrict intellectual property rights, government-funded models and tools ought to be the property of the citizens of the United States and need to be freely available, with no restrictions, as open-source software for community use and development. To enable this more dynamic and productive development environment, NASA could, for example, expand the funding and mission mandate of the GSFC/CCMC facility to support non-NASA researchers in accessing and modifying existing codes or databases under controlled conditions, in analogy with the Developmental Testbed Center for numerical weather prediction (NWP) models run by NCAR through NSF, NOAA, and DoD support.

Strategies Specific to NOAA

The panel suggests that NOAA take the following actions.

1. Establish a dedicated space weather applied research program office within the NOAA OAR division, as recommended by the SWAGF&R23, for implementing the PROSWIFT Act (published April 17, 2023).

The panel concurs with the SWAGF&R23 recommendation and reiterates the need for a dedicated applied research program at NOAA that would be primarily responsible for applied space weather research, funding of external applied space weather research grants to the academic and commercial sectors, and new operational and applications model development for use in space weather forecasting centers and other operational offices. The new program office would also bolster R2O2R within the national space weather enterprise.

2. Expand the scope of space weather missions being designed and flown by NESDIS to address the issues noted earlier (see Section E.4.1) and to realize specific goals discussed here.

In particular, if the required technology is at high TRL and the operational and application capabilities have been demonstrated through previous missions (perhaps at other orbital locations), the panel suggests that NOAA design and fund such space weather operational missions, even if NASA research missions have not been flown in identical orbits. Specific missions could include (in no preferential order; see also Figure E-4(a–c) for additional key space weather observables listed for different orbital regimes):

• A Sun–Earth L4 solar energetic particle and active region monitoring mission (see Goal 1). This mission would enable key energetic particle warning capabilities that are currently lacking. L4 provides a vantage point of the Sun that can track active regions on the solar disk that are most geoeffective from the point of SEP propagation, which is a distinct advantage over observations from along the Sun–Earth line (e.g., Earth-based or at L1). Such an observatory would also support future crewed spaceflight to Mars by providing more comprehensive observations of SEPs and solar activity off the Sun–Earth line. As an L4 mission would provide a new vantage point of the Sun, it is suggested that such a mission include science instruments that address gaps in scientific knowledge with an operational component that allows for public access to measurements in real time.

• A dedicated LEO “calibration satellite” fleet, to enable thermospheric density model assimilation (see Goal 2). Such a fleet is currently tracked by DoD, but its data are not publicly available. As the Department of Commerce stands up a civil space traffic coordination function equivalent to the current DoD capability, it will be imperative to replicate this key space weather measurement capability in an open environment.
• A global, dual-hemisphere auroral imaging mission (see Goal 5). This mission would ideally provide continuous imaging of the entire auroral ovals in far ultraviolet (FUV) for both the northern and southern hemispheres simultaneously. Real-time observations of the full auroral ovals would provide invaluable nowcasting and forecasting capabilities compared to the current state-of-the-art auroral activity model, which is an empirical model using statistical results from archived data sets.

3. Clarify the role of space weather proving grounds in the R2O transition process.

To address the concerns noted in Section E.4.1 and to make clear that the wider community will have a role in this new type of facility, NOAA could hold open and transparent public meetings specifically designed to engage the wider community in this new concept.

4. Increase support for the Space Weather Testbed as a forum for researchers, forecasters, and end user engagement (related to preceding item).

Furthermore, the panel suggests that NOAA provide, and continuously update, a baseline of current operational model and forecast product performance metrics and skill for the validation of new capabilities in the proving grounds and testbed.

5. Establish a program in NWS to coordinate and provide long-term support for ground-based (including air- and sea-borne) space weather observations used in space weather operations (in agreement with SWAGF&R23 Recommendations R.6.1, R.6.2, R.6.3).

Examples of these observations include, among others, the GONG solar magnetogram and H-alpha observing network, the magnetometer network, the Simpson Neutron Monitor Network, and the Continuously Operating Reference Stations (CORS) GNSS receiver network. The panel also suggests that this office lead efforts to develop, expand, optimize, and modernize ground-based space weather observation. These would include, for example, ngGONG and a concept to develop a system of sea buoy–based GNSS receivers. It would also include contributing to the modernization of the DoD Radio Solar Telescope Network (RSTN).

6. Expand support for commercial data buys for assimilation into space weather forecasting models.

Provisions for free and open public access to the data, once they are purchased by NOAA, need to be an element of this strategy.

Strategies Specific to NSF

The panel suggests that NSF take the following actions.

1. Support the design, construction, and operation of ground-based facilities for space weather research that can serve as proving ground for ground-based operational facilities (see also Figure E-8). In concert with the new NOAA/NWS office discussed earlier in Section E.4.2.1.3, item 5, the NSF would work to increase the availability of space weather–relevant, ground-based observations for research and forecasting.
2. Expand the Faculty Development in Space Science (FDSS) program to include a Faculty Development in Space Weather (FDSW) program. This would be a primary source of support to realize the cross-agency strategy described earlier (see Section E.4.2.1.1). FDSW faculty could be based in engineering colleges to ensure cross-fertilization with application-focused instrument and mission development programs.

3. Expand educational opportunities for space weather–related hardware and research programs (related to preceding item). Students and early career scientists benefit greatly from CubeSat, summer schools, and faculty development programs run through the NSF.
4. Encourage and support the development and use of OSSEs to validate new space weather-relevant, ground-based observatories (related to the first item in the preceding subsection) and qualify their potential benefits to operational systems.

Strategies Specific to Each Priority Goal

The goals are listed in the order in which they appear in the previous chapter—that is, grouped by priority category. See the Summary Table at the end of this section. Under each goal, the strategies are not ranked.

Goal 1: Develop an Accurate and Reliable 12-Hour Lead Time Probabilistic >M1 Solar Eruption Forecast and Associated SEP Event Forecast with 6-Hour Lead Time

Summary of Goal

Solar magnetic eruptions are the root cause phenomenon behind extreme and life-threatening space weather events. Current human-in-the-loop and model forecasts have unrealistically long lead times (up to 72 hours) and low skill at all lead times. To achieve usable forecasts for users across multiple end user groups, reliable solar eruption and SEP forecasts with shortened lead times at or below 12 hours need to be developed.

The strategies to achieve this goal include theory, modeling, and observational efforts to better understand the evolution and eruption potential of active regions, the early stages of formation and growth, and triggering and evolution of coronal mass ejections (CMEs) and CME-driven shocks, and the acceleration and transport of solar energetic particles (SEPs) to various locations in the inner heliosphere.

Basic research needs:

• Continuous high-resolution helioseismic observations of subsurface active region formation, flows, and emergence over the lifetime of specific active regions.
• Chromospheric and coronal vector magnetic field measurements to assess whether magnetic activity in these regions is a more effective predictive indicator of eruption triggering.
• In situ SEP energy, flux, and compositional measurements from multiple locations to ascertain where and how SEP generation takes place in active region reconnection sites and in CME shock-fronts.
• Well-funded R&A programs for fundamental space weather research studies to improve understanding of emerging magnetic flux, coronal and chromospheric magnetic fields, active region eruption potential, coronal mass ejection and shock formation and expansion, and particle acceleration and transport, including magnetic connectivity.
• Photospheric magnetic field measurements of the polar regions (>60° latitude) for improved background solar wind models and polar coronagraphic imaging for CME propagation structure. Additional coronagraphic and magnetogram measurements of coronal connectivity from polar vantage points are expected to enhance knowledge of magnetic connectivity between active regions and topology of the inner heliospheric solar wind, CME propagation, shock structure, and evolution, and hence aid in predicting SEP generation and propagation through the inner heliosphere.

Applied research needs:

• Simultaneous full 360-degree measurements of photospheric magnetic field in the solar mid- to low-latitude regions, coronal imaging, helioseismic flowfields, and coronagraphic structure. This is needed to have measurements of active region structure, evolution, and eruption that can be analyzed to advance eruption prediction and SEP generation.
• Sustained funding for space weather applied research centers dedicated to developing advanced models for predicting solar eruptive events and SEPs. Such centers could be part of a dedicated space weather

• research program for data assimilative and/or AI/ML models of active region evolution to eruption and AI/ML techniques for sparse data sets, data-assimilative time profile forecasts, and forecasts for extreme events, with increased accuracy and lead times.
• Development of small and versatile instruments for energetic particle measurements so that they may be readily added as rideshares to other packages and distributed everywhere throughout the heliosphere.
• Development of robust methods for absolute and relative calibration of solar magnetograph instruments.

Operational needs:

• Observations of the western hemisphere of the Sun (e.g., from the Sun–Earth L4 point) for active region and SEP monitoring by the next solar maximum (~2035). A minimal set of measurements would include intensities of energetic particles (electrons, protons, and heavier ions, species resolved) over energies ranging from tens of keV to hundreds of MeV (MeV/nuc for heavier ions), EUV and X-ray measurements of the solar disk, a coronagraph, and a magnetogram to measure active region development not well characterized from observations on the Sun–Earth line. Such observations would also support SEP forecasts for the Earth–Mars transit corridor, in support of the Mars missions planned in NASA’s Artemis program (see Long-Term Goal 2).
• Solar photospheric magnetograph and high-energy particle instruments to be included in the next generation of L1 and GEO space weather platforms.
• Real-time availability of all relevant space weather data, including
  • Measurements discussed in the applied research needs.
  • In situ SEP and energetic electron measurements and eruption location and timing information.
  • Ground- and space-based radio measurements of shock formation and particle acceleration signals.
• The development, validation, and transition of flare and SEP forecast models into operations and the establishment of pre-eruptive ensemble modeling capabilities.

Goal 2: Develop Physics-Based, Data-Assimilative, Thermospheric Neutral-Density Models, Including an Integrated Modeling Framework for Predicting Leo Satellite and Debris Trajectories, Capable of Accurate and Reliable Forecasts During Geomagnetic Storms

Summary of Goal

It is not enough to have a two-line element (i.e., Keplerian plus fitted drag) model of the proliferated LEO environment to successfully operate the multiple mega-constellations (i.e., thousands of satellites per constellation) planned for this region of geospace and to ensure that the region remains a viable orbital regime for research, exploration, and commerce in the future. It is necessary to develop a model of how satellites and debris interact with the geospace orbital environment and how these interactions influence orbital trajectories. A critical aspect of improved orbit prediction in LEO is the ability to better model, nowcast, and forecast the thermospheric environment, especially its 3D (i.e., latitude, longitude, and altitude) dynamics during geomagnetic storms. Physics-based models empowered by data assimilation using actual observations from proliferated LEO offer much promise for advancement on this goal. This goal, while not strictly a “space weather” goal, is critically important to accomplish in order to improve our ability to characterize the LEO environment and to create better models and tools for satellite operators and space traffic management coordinators to use in ensuring a safe operating environment in proliferated LEO and the viable usability of LEO in the foreseeable future.

Basic research needs:

• Measurements from GDC as prioritized in the previous solar and space physics decadal survey. Such measurements are critical to understand ionospheric and thermospheric variability, including neutral-density changes during geomagnetic storm periods. Such observables, including several of those to be made by GDC, were also highlighted as critical gaps in the NASA Space Weather Science and Applications Observational Gap Analysis.

• Fundamental investigations of the physics driving the dynamics of the ionosphere and thermosphere. In particular, such research studies need to focus on aspects that would be particularly advantageous to advance with the goal of data-assimilative modeling in mind. The thermosphere is strongly coupled to Earth’s ionosphere, which in turn is strongly coupled to the magnetosphere. Magnetospheric physics also directly impact Earth’s thermosphere (i.e., auroral processes and energetic particle precipitation). Investigations can focus on either physics-based models that can be stably adjusted using actual observational data (e.g., via a Kalman filter) or the observational data sets required to drive data assimilative models.
• Development of gas–surface interaction physics research, including the development of advanced drag coefficient models for a wide range of satellite geometries, materials, and attitude profiles. This would include (a) characterization of gas–surface interactions and other nonconservative forces in LEO, and (b) laboratory measurements and characterization of gas–surface interactions in orbital environments.
• Development of advanced satellite force models that include drag, radiation pressure, and other nonconservative forces.

Applied research needs:

• Sustained funding for space weather applied research centers dedicated to developing advanced coupled models of the magnetosphere and ITM system along with the required data assimilation models to enable accurate and reliable thermospheric forecasting during geomagnetic storms. These centers would also develop new methods to integrate near-real-time solar spectral irradiance measurements into ITM models and advanced ML approaches to M-I coupling functions and data assimilation improvements.
• Developing instruments and missions as pathfinders for operational follow-ons, as follows:
  • Small-scale accelerometer and mass spectrometer instrumentation for deployment in CubeSat-scale constellation missions.
  • Dedicated rapidly deployable “thermospheric density probes” for near-real-time density data from deployment to reentry into the lower atmosphere during geomagnetic storms.
  • Continuous monitoring of the thermospheric neutral density in LEO across all latitudes.
• Advanced civil ground-based optical telescopes and adaptive optics for LEO satellite and debris tracking research.
• Advanced civil ground-based radar network for characterization of orbital debris down to 1 cm scales.
• Dedicated LEO, MEO, and GEO satellite missions focused on measurement and characterization of orbital debris.

Operational needs:

• Altitude-resolved temperature measurements in the mesosphere–lower thermosphere (MLT) region—that is, pressure altitudes of 20 to ~120 km. Such data are currently being assimilated from the last remaining SSMI scanner on DMSP F17 (launched in 2003) and have been demonstrated as key assimilation sources for coupled whole atmosphere models extending into the upper thermosphere, but there is a need to replace and extend the current measurements for assimilation into NOAA and DoD thermosphere models.
• Development of a dedicated LEO “calibration satellite” constellation for radar tracking data inputs to thermospheric density models (i.e., a civil version of the USSF calibration objects used in HASDM). Such a constellation could be developed with agency support and then transitioned to the commercial sector to generate radar tracking data buys (e.g., see development chain for new operational observatories in Figure E-8). The existing International Laser Ranging Satellite (ILRS) satellites are suboptimal for this purpose owing to their complex surface properties that result in uncertain drag coefficients.
• Research to establish commercial LEO satellite constellation precise orbit determination (POD) data as assimilation sources for operational thermospheric neutral-density forecasting models.
• Advanced satellite orbit propagation and conjunction analysis models with integrated space weather models, customizable visualizations, and scenario testing.

• Integrated thermospheric neutral density, satellite forcing, and orbital propagation models for improved collision assessment and risk mitigation by LEO satellite operators. Note that part of this (thermospheric density model) is the same as the thermospheric density model development portion of this goal.

Goal 3: Characterize and Monitor the Space Weather Environment in Cislunar Space and on the Lunar Surface in Support of the Artemis Program

Summary of Goal

The United States is investing major resources in the NASA Artemis human space flight program, which will see astronauts working on the surface of the Moon in the next decade and eventually setting foot on Mars. To support the Artemis program, it will be imperative to develop the knowledge, measurements, and tools to ensure astronaut safety in these extremely challenging and dynamic environments.

The strategies to achieve this goal address the need for measurements in new environments, improved modeling of the space radiation and charging environments, and new space weather monitoring locations. Distributed particle and radiation measurements are needed throughout the broader heliosphere, in cislunar space, and on the lunar surface to better characterize and model the dynamics of those radiation and charging environments. Improved modeling of the relevant radiation and charging environments is needed to inform human exploration. New space weather monitoring of the Sun’s western hemisphere from Earth–Sun L4 would fill existing gaps. Interagency cooperation would facilitate the development of tools and transitioning of forecasting models into operations. Note that several of the suggested strategies under Goal 1 are also relevant and contribute to the strategy of achieving this goal.

Basic research needs:

• The following new observations to characterize the changes in the lunar environment, particularly owing to its orbit with respect to Earth’s magnetotail or in response to solar energetic particle events.
  • Particle (neutrons, electrons, ion composition) distribution (thermal to very energetic particle) measurements in different exposed and shielded environments on the lunar surface, including under the regolith and inside lava tubes.
  • Energetic neutron measurements on the lunar surface to better quantify cosmic ray albedo neutrons that are currently estimated through modeling and are potentially a significant source of radiation dose.
  • Energy-resolved measurements of keV to MeV electrons from magnetotail acceleration on the lunar surface (surface charging to penetrating radiation threats), in lunar orbit, and in lunar transfer orbit.
  • Advances in modeling and measurements of the lunar dust environment, in particular how electrostatic and/or dynamic electric fields loft and deposit dust and how dust contributes to the surface charging and discharge hazard to humans, vehicles, and infrastructure.
• Energetic particle measurements distributed throughout the heliosphere on human exploration, heliophysics, and planetary missions to better understand energetic particle production and transport. Such observatories will also support future missions to Mars by providing knowledge of SEP propagation throughout the heliosphere off the Sun–Earth line (considering that Earth-to-Mars transfer orbits are off the Sun–Earth line within the ecliptic plane).

Applied research needs:

• Studies to improve characterizations and predictions of the cislunar radiation environment, including
  • Predictions of solar energetic particle event profiles for consideration in human radiation exposure and SEE mitigation.
  • Effects of variation in the radiation environment on the lunar surface owing to topography and secondaries produced in the regolith.
  • Modeling of the space radiation environment both external and internal to spacecraft (e.g., Gateway) and lunar surface habitats.
• Strategies relevant to Goal 1 on the SEP and eruption measurements and forecasting.

• The following new observational capabilities to complement the Heliophysics System Observatory (HSO) for the following observing capabilities:
  • Photospheric and coronal magnetic fields and photospheric vector magnetogram measurements from multiple viewpoints around the Sun, including polar vantage points.
  • Coronagraph and heliospheric imager observations of CMEs from multiple viewpoints around the Earthward hemisphere of the Sun, including polar vantage points.
  • IMF and particle measurements from locations throughout the heliosphere for data assimilation into models.

Applied research needs:

• Sustained funding for space weather applied research centers dedicated to developing advanced models for prediction of solar wind and CME Bz at Earth. Such centers could establish space weather research programs for data assimilation and ensemble modeling techniques for empirical and physics-based codes of CMEs and solar wind.
• Plasma, energetic particles, and magnetic field measurements closer to Earth than L1 (peri-geospace). This is needed to evaluate and understand the accuracy of measurements at L1 and closer to the Sun (i.e., sunward of L1) for predictive magnetospheric models and solar wind-magnetospheric coupling.
• Technology demonstration to raise the TRL of solar sail technology as a means to obtaining more inner heliospheric observations at a variety of locations along the Sun–Earth line.

Either through an operational or through an applied research program, plasma and magnetic field measurements are needed both Sunward and Earthward of L1. Measurements relatively close to L1 (0.95–0.98 AU from the Sun) and Earthward of L1 would be best adapted to an operational program, whereas measurements closer to the Sun would be part of an applied research program or through an augmentation to a basic research space mission. Measurements from ~0.95 AU can improve the lead time to a few hours and make progress toward the goal. Measurements closer to the Sun combined with data assimilation, modeling, and remote observations are needed to reach closure on the goal.

Operational needs:

• Real-time (1) coronagraph images from L1 and at least one more location off the Sun–Earth line (ideally two more locations); (2) radio measurements from the ground; (3) photospheric vector magnetograms from the ground, Earth’s vantage point (L1), and one more location east of the Sun–Earth line; (4) extreme ultra-violet measurements from Earth’s vantage point and one more location east of the Sun–Earth line; and (5) Heliospheric Imager measurements from at least one location off the Sun–Earth line (ideally two locations).
• Improved operational heliospheric solar wind modeling and/or propagation techniques for CMEs, including their magnetic field, and improved solar wind tracking, tomography algorithms/models, assimilation techniques for remote observations.

Goal 5: Develop Nowcast Capability for Comprehensive Characterization of Auroral Activity, Including Intensity, Boundaries, and Energy Inputs

Summary of Goal

Auroral activity is directly relevant and important to several critical aspects of space weather, including (1) the spacecraft charging and radiation environments in proliferated LEO; (2) the current systems that drive GICs; and (3) ionospheric and thermospheric disturbances and energy inputs that affect communications, navigation, and satellite drag. Currently, operational models of auroral activity are limited to empirical models driven by statistics of historical data sets, and there are no simultaneous, continuous, comprehensive observations of auroral activity

in both northern and southern hemispheres. In addition, auroral activity is of high interest to the general public and is a proven pathway for bolstering public support and even citizen science of space weather.

Basic research needs:

• Support utilization of an augment to the HSO that allows for simultaneous observations of multispectral auroral imaging from the ground and space alongside suprathermal to energetic particle measurements from LEO.

Applied research needs:

• FUV and energetic particle augmentations (see Annex E.B) to candidate missions that would support (at least in part) observational objectives required to achieve Goal 5.
• Sustained funding for space weather applied research centers dedicated to developing advanced models for auroral activity and its effects on the ionosphere–thermosphere systems and satellites in LEO. Such centers could be responsible for the development of advanced, probabilistic models of auroral that meet the needs of vested end user communities and support the development of modeling approaches that refine resolution to capture mesoscales in global auroral predictive models.
• Development of next-generation ground-based auroral observing technologies.
• Continued observation of polar cap potential via technologies such as SuperDARN.
• Observations of Field Aligned Current patterns through approaches like Active Magnetosphere and Planetary Electrodynamics Response Experiment (AMPERE).

Operational needs:

• Deploy a set of space-based observatories providing real-time, comprehensive (i.e., full oval) observations of the auroral ovals in both the northern and southern hemispheres, simultaneously and continuously. Note that FUV wavelengths are nominal for such observations because those can be made in both sunlit and dark hemispheres.

Goal 6: Develop Reliable Probabilistic All Clear Forecasts with Multiday Lead Time

Summary of Goal

An All Clear forecast indicates that the space weather environment will be quiet, clear, or nonthreatening for a predetermined duration (e.g., 12 or 24 hours). An All Clear forecast may indicate that a driver, such as a solar eruption or the arrival of a CME, will not occur. Alternatively, an All Clear forecast may indicate that an impact, such as a geomagnetic storm or increased atmospheric drag, will not occur. All Clear will have different definitions for different phenomena and end users and would be developed independently for each need. End users would benefit broadly from accurate and reliable probabilistic forecasts that given phenomena will not occur, or will come to an end, in a specific timeframe at a specific location.

The strategies to advance All Clear forecasting include improved knowledge of the physical processes that drive eruptions and subsequent variability of the conditions in the heliosphere and geospace environment (including cislunar space, magnetosphere, ionosphere, thermosphere, and ground/GICs environments). These strategies additionally support Long-Term Goals 1 and 2.

Basic research needs:

• Studies and modeling of the physical processes that drive space weather, including the physical processes that drive solar eruptions, propagation of structures and particles in the heliosphere, arrival of structures and particles at Earth and corresponding impacts in the magnetosphere–ionosphere–atmosphere system-of-systems and on the ground.
• Full-Sun, including polar regions, observations as noted in Goal 1.

• Support and provide spatially dense magnetometer observatories at middle latitudes to characterize the spatiotemporal geomagnetic disturbances driving geoelectric field and enable validation of predictive models.
• Support for sustained development of coupled models of the geospace environment through R&A programs for fundamental space weather research studies and applied research centers. These centers would also develop new methods to provide reliable probabilities and multiple realizations of higher-dimensional predictions, incorporating new approaches in data science and data assimilation to accelerate improvements in skill.
• Fund space weather research programs for quantifying event likelihood and hazard impacts for geoelectric hazard.
• Support for modeling work to develop, and validate, probabilistic models of geoelectric field at regional scales and tools producing multiple realizations of spatiotemporal geoelectric field.
• Fund science missions to observe and resolve direct connections between in situ magnetospheric activity and structures and auroral activity and features, providing a pathway to using auroral imaging in hazard zone predictions and resolving the phenomena driving the mesoscale current systems responsible for intense geoelectric fields.

Applied research needs:

• Operations support for probabilistic forecast models of geoelectric field and other tools developed in tandem with power transmission end users.
• Completion of the magnetotelluric survey of the United States and full characterization of the uncertainties associated with the transfer functions. International collaboration to complete a similar survey north of the United States–Canada border would significantly augment the value of the U.S. survey.
• Following open science best practices, the coordinated gathering, dissemination, and archiving of GIC, magnetic disturbance, and geoelectric field measurements.
• Support and provide geoelectric field measurements for model development and validation.

Operational needs:

• Increased spatial resolution magnetometer observations to characterize, at regional scales, the spatiotemporal geomagnetic disturbances driving geoelectric field at midlatitudes, improve nowcasting, and enable validation of predictive models.

Goal 8: Develop a Reliable Probabilistic Forecast of Surface Charging (3 Days), Internal Charging (28 Days), Single-Event Effects (SEE; 6 Hours), and Event Total Dose (1 Day)

Summary of Goal

Satellite and launch operations are affected by several energetic charged particle hazards. Forecasts at the specified timetables are believed to be achievable within 10 years, and initial versions with shorter lead time or lower accuracy are already used today in operations. However, generally operators report that they can improve their operations with longer lead time and more accurate forecasts. The strategies to achieve the goal include new research and operational observations, research and operational, research and operational model development, and decision aid development.

Basic research needs:

• Fundamental science modeling of upstream drivers (CMEs, SEPs, high-speed streams) and magnetospheric particle populations (hot electron plasma, radiation belt particles, geomagnetic cutoffs).
• Additional scientific observations of hot electron plasmas and geomagnetic cutoffs (with energy, species, and angular resolution).
• Supporting data sets to contribute to the physical processes governing the hazardous particle populations—for example, ULF and VLF waves and DC fields.

• Modeling efforts, including AI/ML, connecting dynamo and/or flux transport processes to specific solar activity.
• Research to evaluate how well sunspot number and F10.7 reflect (i.e., are proxies for) actual solar activity relevant to space weather hazards.

Operational needs:

• Continued long-term measurements to enable a continuous record of solar activity over multiple solar cycles—in particular, sunspot number, F10.7, full-disk magnetograms.
• Establish use of EUV imagery for solar cycle predictive capability as an improved (i.e., higher information content) and alternative method to the traditional use of F10.7cm radio flux.
• Establish a U.S. national capability to obtain continued measurements of the ground-based F10.7cm radio flux as a proxy for solar EUV irradiance over the solar cycle. This provides ongoing continuity with long-term, historical F10.7cm data sets, while also ensuring sufficient data coverage overlap to establish statistical relationships between measured EUV imagery and corresponding F10.7cm radio flux.

Goal 10: Develop a Robust Reanalysis Capability for Forecast/Nowcast Models with Established Community Standard Input Data Sets for All Key Space Weather Drivers and Impacts

Summary of Goal

Reanalysis refers to the process of creating a long-term reconstruction of the state space in the space weather environment. End users employ reanalysis to refine data from the past that determine either specific conditions during a past or ongoing mission or to establish cumulative and worst-case transient design environments. Standard state space models are needed for all key space weather drivers and impacts—in particular, of the magnetosphere and the ITM system spanning many solar cycles.

The strategies to accomplish this goal focus on developing a more robust system for space weather data products dissemination, better collaboration between the agencies, and a complete set of ground- and space-based observations with their proper archives available for the research and operational communities.

Basic research needs:

• The development of (1) robust, detailed, and open-archived version-controlled historical data sets to drive data assimilative models; and (2) new data assimilative models across all relevant space weather domains.
• Partnerships with international agencies to share the technical load for establishing trusted data sets for use in data assimilation and developing the long-term, data-assimilative simulation models.
• Development of numerical simulations that can run for 1+ solar cycles in reasonable timeframes.
• Extension of numerical simulations to cover the entire geophysical domain relevant to technological systems (e.g., add LEO to global radiation belt and plasma models).

Applied research needs:

• Establishment of a clearinghouse for massive data sets from full solar cycle model runs.
• Development of standard file formats and extraction/projection software to map from model grids to real locations.
• Continued long-term, ground-based observations.

Operational needs:

• Continued long-term, space-based observations in GEO, MEO, and LEO and upstream solar wind monitoring.

• Enhanced metadata standards to include information regarding, for example, the timing of observational availability to models and forecasts as it happened in real time and the status of primary and secondary satellites that were used to make the forecast.
• Archiving and public dissemination of operational model outputs for scientific model validation by the research community.

Goal 11: Develop 30-Minute to 1-Hour Lead Time Forecasts of Transionospheric and Skywave Mode HF Radio Wave Signal Impacts (Such as Ionospheric Scintillation, Absorption) in Polar, Midlatitude, and Equatorial Regions

Summary of Goal

The strategies to accomplish this goal focus on enhancing the data available (space and ground) for assimilative models, supporting new and improved modeling approaches for nowcasting and forecasting, and coordinating and supporting ground-based observations as integral to the real-time data ecosystem.

Basic research needs:

• Fund fundamental space weather research studies to improve understanding of ionospheric electron density structuring, drivers and associated impacts on specific users (includes coordinating to obtain appropriate impact data—e.g., OTHR radar data).
• Fund model development for characterization and validation of 3D, time-evolving ionospheric electron density, and if appropriate, including coupling to other regions (e.g., magnetospheric models) to resolve spatial and temporal structures of relevance.
• Fund model development of auroral transport and ionospheric models to enable understanding of particle precipitation effects on ionospheric structure and GNSS signal propagation in the polar ionosphere.

Applied research needs:

• Fund augmentations of LEO and MEO science and commercial missions with GNSS RO instrumentation, enhancing the number of RO profiles/day. For these missions, consider possibilities to reduce data latency in mission optimization. See also this panel’s suggestions for related augmentations to missions that underwent the technical, risk, and cost evaluation (TRACE) process (see Appendix G).
• Fund space weather research to develop probabilistic models of electron density impacts associated with different drivers (flares, substorms, etc.).
• Coordinated effort to align NSF and NOAA funding opportunities for advancement in ground-based observational capacity and user needs specifications.
• Lower the barrier of usage for GNSS ocean-buoy network data, and expand the network to optimize coverage for data-assimilative models.
• Engage end users and define appropriate modeling targets and outputs. Work with end users to make data available to space weather research for development of impact-specific models and forecasts.
• Develop forecast tools capable of predictions of electron density structures and associated user impacts in different regions (high-latitude, midlatitude, etc.).
• Continue support for ground-based GNSS instrumentation program (low-cost and scintillation receivers). Fund dedicated activities to enhance real-time data recovery and low-latency enhanced data products (i.e., GNSS TEC with bias determination and removal) to support operational use of systems.

Operational needs:

• Coordinate the development of a comprehensive global network of GNSS TEC measurements with common data interfaces and real-time data availability.
• Coordinate ocean-buoy network optimization and associated data pipelines.

• Ensure that all relevant observations are available in real-time, including
  • Measurements from the ground-based neutron monitor network used to monitor the background GCR and characterize the high-energy component of solar energetic particle spectra.
  • Direct measurements of the relevant, incident energetic particle populations precipitating into the atmosphere (e.g., high-energy proton and alpha measurements from the GOES spacecraft), including the development and launch of an instrument with >500 MeV differential particle flux observing capabilities.
• Enable development, validation, and transition into operations for a real-time nowcast and forecast model of geomagnetic cutoffs and intensities for all relevant particle species and energy ranges.

E.5 LONG-TERM GOALS AND STRATEGIES

E.5.1 Long-Term Goal 1: Establish an Interconnected System of Observatories, Data Pathways, and Applied Research and Modeling Centers

An interconnected space weather system—for example, the Space Weather Aggregated Network of Systems (SWANS) detailed in the community input paper by Vourlidas et al. (2022)—is essential to serve society’s space weather needs by developing and networking an aggregated system of in situ and remote sensing observatories, both space-based and ground-based, and state-of-the-art modeling facilities and centers that will provide space weather end users with accurate, on-demand resources to predict the consequences of space weather on systems distributed on and around Earth and throughout the solar system. Faced with a complex and highly nonlinear system, the strategy is to approach space weather as a “system-of-systems.” This allows for the treatment of the space weather problem as a chain of smaller interconnected systems with a research infrastructure plan developed around each of them.

Current space weather observatories, data sources, and modeling capabilities are managed as completely separate assets by independent institutions, teams, and even individuals. In the long term, this is neither a sustainable nor an efficient model for addressing space weather needs. Societal demand for improved space weather evaluation and prediction models is ever-growing as humanity becomes more and more reliant on space-based technology and strives to explore our solar system. Whereas interoperability and data sharing are nice to have in the pursuit of scientific understanding, they are essential for space weather, which often confronts very short timelines to support society in response to a new space weather challenge. For example, SpaceX resumed launch operations only 3 weeks after losing dozens of vehicles in a February 2022 SpaceX anomaly that was attributed to space weather. The infrastructure needs to be in place before the problem arises, because operations cannot be put on hold for extended periods while infrastructure is built. Each piece of the space weather chain needs to be developed and implemented as part of a greater framework. A system-of-systems approach will better empower next-generation space weather capabilities.

Key aspects of such an interconnected space weather system include the following:

• Close collaboration and partnership with the commercial sector.
• Simple, streamlined observatory design and operations.
• Rapid deployment and scalability.
• Establishment of a dedicated, real-time, global communications network enabling very low latency data streams from both ground-based and space-based observatories.
• Data analytics, including ML and advanced data-mining approaches to handle data products from a large, distributed network of observatories.
• Streamlined and accessible data pipelines, cloud computing, and advanced data-ingestive and data-assimilative modeling forming the core components of an interconnected and accessible data system and corresponding centers.
• Strong modeling component leveraging both data-augmented, physics-based models and purely data-driven models.
• Community-wide participation.

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¹⁹ Unified Data Library Storefront, https://unifieddatalibrary.com/storefront/#/login?returnUrl=%2F.

²⁰ The term “instrument pantry” was coined by Nicola Fox during her tenure as director of NASA’s Heliophysics Division. Mention of the concept appears in a presentation made by the co-chairs of the National Academies’ Committee on Solar and Space Physics, at https://sites.nationalacademies.org/cs/groups/ssbsite/documents/webpage/ssb_189684.pdf. A lengthier description of its utility for space weather appears in the minutes of the inaugural meeting of the NASA Space Weather Council on March 2, 2022, at https://smd-cms.nasa.gov/wp-content/uploads/2023/05/SWCMarch22022MinutesasAdopted.docx.

Also needed are expanded funding opportunities for new instrument technology research and development and low-cost flight opportunities for access to space under existing program lines (e.g., HTIDES, LCAS, HFORT) and the new NASA SWxSA program. NOAA might also consider dedicated funding opportunities for instrument development and “pantry” filling. Efforts dedicated toward developing instrument interface (including, mechanical, electrical, digital) standards and requirements would reduce the burden (cost and schedule) of having to redesign or customize interfaces for each particular flight opportunity.

Vision for Organization and Implementation

Figure E-10 shows a more detailed evolution of the network-of-systems over the next 15+ years. The emphasis is on making key technological and infrastructure investments early that allow for multipoint observatories to be developed and then observatories or the technology behind them to be transitioned into operations.

Related Priority Goals and Strategies

Nearly all of the cross-agency strategies highlighted in the Strategy portion of this report describe advancements that are relevant to achieving Long-Term Goal 1. In the coming decade, each strategy could be implemented with foresight, treating it as an individual component that will ultimately be a part of a broader interconnected system-of-systems. Working purposefully toward this long-term vision over the next decade will facilitate the establishment of streamlined and robust space weather capabilities in the following decade.

Most of the priority goals and their strategies are directly analogous or closely related to Long-Term Goal 1, in particular the following.

Goal 2: Develop physics-based, data-assimilative, thermospheric neutral-density models, including an integrated modeling framework for predicting LEO satellite and debris trajectories, capable of accurate and reliable forecasts during geomagnetic storms. This goal highlights the need for an accurate satellite drag and debris trajectory modeling system. To accomplish this goal, a complete space weather chain must be in place to robustly collect real-time observational data, process it quickly, and proficiently distribute the results to end users through tailored products. All components of the system-of-systems approach are engaged, providing an opportunity to develop this framework with Long-Term Goal 1 in mind.

Many of the other priority goals involve development of new observational and/or modeling capabilities pertaining to particular space weather drivers or impacts. These disparate yet interrelated goals emphasize the need for an orchestrated systems-of-systems approach. Many of the new developments for the priority goals can be achieved through efforts conducted in parallel with one another; however, because collectively they are all of interest to the entire space weather community, those efforts and their final products should not exist alone and independent of the others. Solutions to some challenges, particularly those calling for new observatory capabilities, can be implemented to deliver on the needs of multiple goals simultaneously, particularly when a new observatory can satisfy multiple goals’ observational requirements from a well-designed, strategic orbital or ground-based location(s). Ultimately, the deployment, operations, and data services for a future aggregated network of space weather observatories and data and modeling centers would be most effective if orchestrated with a strategic, versus ad hoc, implementation.

Goal 10: Develop a robust reanalysis capability for forecast/nowcast models with established community standard input data sets for all key space weather drivers and impacts. The goal to develop a robust reanalysis workflow underscores the need for publicly accessible, standardized data sets. The strategies to achieve this goal include creating a clearinghouse for massive data sets, the standardization of data sets, enhanced metadata, the development of software to interact with those data sets, and improved schemes for archiving and dissemination to the public. Implementing these strategies over the next decade in a purposeful manner to address this priority goal may provide a small-scale example of standardization for key components within the broader aggregated system-of-systems.

• a fast response to changing conditions. The panel suggests that NASA develop the necessary space weather instruments to be located onboard orbiting spacecraft at Mars, transit vehicles, and on the Martian surface to provide data in real time.
• Fund and develop models capable of ingesting local observational inputs and with a capacity to run on the computer systems available to distant astronauts (e.g., tablets, laptops, desktop computers) to provide actionable forecasts in a timely manner.
• The panel suggests that NASA take full advantage of the upcoming Artemis lunar missions to design and prototype onboard space weather instrumentation packages and develop monitoring and forecasting tools for stand-alone use by astronauts.

Related Priority Goals and Strategies

A number of the identified short-term priority goals build toward the scientific understanding and forecast capabilities required to achieve long-term goal 2, including the following:

Goal 1: Develop a reliable 12-hour lead time probabilistic >M1 of solar eruption and potentially associated SEP events forecast with a 6-hour lead time; and Goal 6: Develop a reliable probabilistic All Clear forecast with multiday lead time. Pre-eruptive, longer lead time and All Clear flare and SEP forecasts are required for day-today mission planning and mitigation of adverse impacts—in particular, the protection of crew health by informing them when it is safe to carry out EVAs or allowing them time to construct or return to a radiation shelter and to safeguard avionics. Accurate probabilistic forecasts specifically are required for decision-making and managing risk. Space weather monitoring from the Earth–Sun L4 location is doubly beneficial in that it also informs the space weather conditions for the Hohmann transfer orbit, a likely orbital path choice for humans to travel to Mars. Simultaneous full-Sun observations of the Sun enable space weather monitoring and forecasting for Mars throughout its entire orbit.

Goal 3: Characterize and monitor the space weather environment in cislunar space and on the lunar surface in support of the Artemis program. Many lessons learned for improved modeling of the cislunar environment can be carried forward to the Martian environment—for example, observations returned from new energetic particle detectors monitoring the cislunar environment, the development of small instrumentation operating locally to the transit vehicle and/or an astronaut habitat to independently monitor human and hardware health without communication with Mission Control, and the development of models that more accurately characterize the energetic particle flux throughout the heliosphere. The deployment of an Earth–Sun L4 and/or full-Sun space weather package in the current decade will allow for the development of data products available from that location and forecasting models specific to Mars exploration.

Goal 9: Develop an accurate (to within ±20 percent) 6-month to 1-year forecast of the solar activity cycle. Predicting the gross characteristics (maximum, peak time, duration) of the solar activity cycle is relevant to mission planning involving long-duration human spaceflight, including missions to Mars. While radiation shelters provide astronauts with shielding from transient, relatively short-lived, low-energy SEPs, it is much harder to do so for higher-energy GCR particles. GCRs are modulated by the heliospheric magnetic field and thus are anti-correlated with sunspot number over the course of the solar cycle. Better forecasts of the solar activity cycle, in addition to shorter-term 6-month to 1-year predictions, will be advantageous for mission planners.

E.6 EMERGING OPPORTUNITIES

Assessment of emerging opportunities in this report are based on opportunities or “obligations” to support the safety of activities that are already starting or are foreseen to start over the coming years, and that are sensitive to space weather impacts. The consideration by the panel has not been limited just to space activities; it also includes ground-based and airborne activities where space weather can be considered as one of the main hazards. Some of the foreseen activities and application areas are mainly commercial, and this is foreseen to create other types of emerging opportunities for space weather service provision.

generate surface charging fluxes out to the Moon’s orbit. Thus, a related goal on understanding surface charging in inner geospace is the following:

• Goal 8: Develop a reliable probabilistic forecast of surface charging (3-day lead time), internal charging (28-day lead time), SEE (6-hour lead time), and event total dose (1-day least time) for all orbits.

The strategies for achieving these goals are described earlier in this report.

Space Tourism in LEO, Cislunar (Conducted by Private Sector, Served by NOAA/Private Sector)

The first fully commercial space tourist flights have already started: in 2021 by Blue Origin, and in 2022 by Virgin Galactic. While these suborbital flights are short and barely crossed the 100 km altitude Kármán line that is often used to define where outer space begins, there are plans to expand the tourism to full LEO orbital flights, including orbital hotels, and for commercial cislunar activities and flights orbiting around the Moon. Current suborbital flights require very limited space weather information, although it is not clear whether a launch would be executed during an SEP event. As soon as space tourism includes complete LEO orbital flights or longer-term stays on space hotels, information about the radiation environment in LEO and space weather impact on space operation will be required. If and when space tourism includes flights to cislunar or lunar environments, the need for radiation environment forecast and monitoring information increases dramatically.

The user needs for commercial space tourism for LEO, cislunar, and lunar operations are very similar to the needs of human exploration as described earlier in this report (e.g., in Section E.3.3, Goal 3) and they are supported by the same priority goals.

Because of the commercial customers for these services, however, this opportunity is potentially more geared toward commercial space weather service provision. The panel suggests that space agencies and public entities support development of operational, commercial third-party space weather services. Recent history has shown that commercial space weather services developed on government funding often falter when the government discontinues development support, suggesting that a transition period of government-funded operations and maintenance may be necessary to foster a thriving commercial services sector. Data buys from commercial actors and government agencies acting as anchor customers may be considered in supporting a transition period. It is also important to note that, at least at the beginning, the commercial service providers are unlikely to be able to implement and maintain the space segment facilitating the required forecasting and nowcasting services. Therefore, for this scenario, a publicly funded data acquisition system would need to be maintained and developed further.

E.6.2 Opportunity 2: Proliferated LEO

Orbital regions for operational missions are becoming increasingly congested. Over the past decade, the number of active satellites in space has increased by a factor of 7 from just over 1,000 to more than 7,000. At the same time, the quantity of debris is increasing, particularly in the LEO orbits increasingly used by operational space missions. At the end of 2022, the number of tracked objects in space exceeded 30,000. If efficient methods are not utilized, the probability of catastrophic collisions in orbit is predicted to increase significantly over the coming decades. This could lead to “Kessler syndrome,” the situation in which the density of objects in orbit is high enough that collisions between objects and debris create a cascade effect, each crash generating debris that then increases the likelihood of further collisions. At this point, certain LEOs would become entirely inhospitable.

Space Weather Service to Space Traffic Coordination/Management and Space Sustainability

Space weather is both a positive and a negative factor in the domain of Space Traffic Coordination (STC)/ Space Traffic Management (STM) and sustainable use of outer space. Expansion of Earth’s upper atmosphere owing to solar activity affects the atmospheric drag at orbits below 600 km and causes small debris to reenter and burn in the atmosphere. At the same time, space weather is the largest source of uncertainty in determining

orbital trajectories of LEO satellites and debris objects. During severe geomagnetic storms in particular, satellites and debris are impacted by the increase in thermospheric density in LEO altitudes and, in worst-case scenarios, the orbital tracking catalog used in conjunction assessment and collision avoidance maneuver planning could be completely invalidated for several days. In addition, SEP events are a hazard to the safe launch and operation of satellites and can contribute to creation of new debris when satellites malfunction or their control is completely lost. Space weather is also one of the main contributors to the uncertainty of the impact site in the case of uncontrolled reentry of satellites and large debris such as rocket bodies.

Accurate thermospheric neutral density forecasts are needed for orbit prediction and satellite collision avoidance in LEO, and for prediction of satellite reentry time and location in the case of an uncontrolled reentry. Uncertainty in reentry location creates disturbances in other services—for example, in aviation owing to no-fly zones and a potential risk of impact on populated areas.

This opportunity is addressed by Priority Goal 2: Develop data-assimilative, thermospheric neutral-density models, including an integrated modeling framework for predicting LEO satellite and debris trajectories, capable of accurate and reliable forecasts during geomagnetic storms.

Other user needs and service requirements for STC/STM are not yet well defined. The panel suggests that these user needs need to be analyzed in close cooperation with the relevant regulatory entities and end users, including a gap analysis versus current space weather capabilities. The results from the gap analysis are foreseen to identify O2R/A2R opportunities for development of needed space weather capabilities.

Services to Commercial Operators

To ensure safe space operations and to support space sustainability, the panel anticipates that commercial satellite operators will be subject to the same STC/STM recommendations as public operators and space agencies. Commercial operators will also be expected to have financial interests in the safe operation of their satellites—for example, to avoid increased premiums in insurances of space assets. Future operations for in-orbit servicing and active debris removal will be particularly sensitive to any external disturbance because of the need for close proximity operations.

The panel considers space weather services to commercial operators as an emerging opportunity for commercial actors for business-to-business service provision. It is, however, unlikely that commercial operators will be able to implement their own space weather data acquisition infrastructure, particularly its space segment. Thus, data acquisition by public actors and making the data available for commercial use will be required. Space agencies need to ensure in particular the availability of baseline data from the Sun–Earth line, including in situ measurements from L1 and potentially from locations between L1 and the Sun. Improved SEP event forecasting, nowcasting, and monitoring would require a mission to the vicinity of L4 to monitor active regions that are beyond the west limb of the Sun as seen from Earth, but that are still magnetically connected to Earth.

The opportunity of space weather services to commercial operators is addressed by Priority Goal 2. However, in this case, the suggested strategy for developing commercial space weather services need to also be considered.

E.6.3 Opportunity 3: Protection of Emerging Applications Sensitive to Space Weather

Applications based on autonomous operation of space and ground vehicles are foreseen to emerge during the coming years. Space weather is a potential hazard increasing risks of such operations, creating an opportunity/obligation to provide information reducing the risk.

Autonomous Space Transport, Rendezvous, and Docking

Satellite close proximity operations required by future In-Orbit Servicing (IOS) and Active Debris Removal (ADR) services in LEO will, in most cases, be based on autonomous operation of the servicing spacecraft because the operation has to be executed outside the communication range of the operating ground station. Close proximity operations are extremely sensitive to external disturbances, and a software or hardware anomaly on either spacecraft may cause a collision and loss of one or both missions.

(Space Weather) as part of the Long-Term Sustainability of Out Space Activities (LTS) in 2011. The follow-on Space Weather Expert Group reporting to UN COPUOS under a permanent agenda item was approved in 2015. One of the results of the work by this group was a letter in July 2022 from the UN Office for Outer Space Affairs (UNOOSA) to the World Meteorological Office (WMO), Committee on Space Research (COSPAR), and International Space Environment Service (ISES) to lead efforts to improve the global coordination of space weather activities in consultation and collaboration with other relevant actors and international organizations, including the UN COPUOS. The first international meeting on this context was held in November 2023 in Geneva.

The Coordination Group for Meteorological Satellites (CGMS) has been coordinating space weather observations by operational satellite missions since the establishment of the CGMS Space Weather Coordination Group (SWCG) in 2018. The SWCG supports the continuity and integration of space-based observing capabilities for operational space weather products and services throughout CGMS and the user community and the CGMS operators with regard to space weather phenomena. Particularly, the SWCG coordinates space weather activities within and across CGMS working groups, including space weather data, ensuring that space weather operational measurements are incorporated into the CGMS baseline, relevant frequencies, anomaly resolution, products, knowledge, and policy.

At present, there is no similar coordinating forum for scientific space-based space weather observations. In addition, there is no international coordinating forum for ground-based operational or scientific space weather observations. The panel suggests that such a coordination group would be established to facilitate joint international efforts to ensure the continuation and enhancement of space weather observations for scientific research. One potential approach for such a group could be the International Agency Space Weather Coordination Group (IASWCG) model presented in the November 2023 meeting organized by WMO, COSPAR, and ISES in Geneva.²¹

Space weather is also a topic in many international conferences. The most well-known conferences focusing mainly on space weather include the annual Space Weather Workshop in the United States, European Space Weather Week (ESWW), the Asia-Oceania Space Weather Alliance (AOSWA), the Space Weather Observations Throughout Latinoamerica (SWOL) workshop, and the Conference on Space Weather organized in the framework of the American Meteorological Society (AMS) annual meeting. Space weather and heliophysics-related sessions are also regular parts of the European Geophysical Society (EGS) and American Geophysical Union (AGU) meetings.

E.7 REFERENCES

Abt Associates. 2019. Fina Report: Customer Needs and Requirements for Space Weather Products and Services. National Weather Service; Space Weather Prediction Center. https://repository.library.noaa.gov/view/noaa/29107.

Andorka, S., J. Cox, and M. Fraizer. 2021. “SDA Environment Toolkit for Defense (SET4D) – Enabling Attribution for Orbital Assets and Electro-Magnetic Spectrum Links through Streamlined R2O.” https://amostech.com/TechnicalPapers/2021/Poster/Andorka.pdf.

Bain, H.M., K. Copeland, T.G. Onsager, and R.A. Steenburgh. 2023. “NOAA Space Weather Prediction Center Radiation Advisories for the International Civil Aviation Organization.” Space Weather 21(7):e2022SW003346. https://doi.org/10.1029/2022SW003346.

Bosilovich, M., R. Cullather, and National Center for Atmospheric Research Staff (eds.). 2024. “The Climate Data Guide: NASA’s MERRA2 Reanalysis.” https://climatedataguide.ucar.edu/climate-data/nasas-merra2-reanalysis.

Brown, K. 2022. “HERMES: A Small External Payload for Gateway with Big Challenges.” IEEE Aerospace Conference 2022. https://ntrs.nasa.gov/api/citations/20220003079/downloads/HERMES%20IEEE%20Aerospace%20Confernece%20Presenation%2020220308%20FINAL.pptx.pdf.

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²¹ “The idea of this International Agency Space Weather Coordination Group would be that it would be a forum for those agencies that fund space weather research and observations to plan, coordinate and partner to implement space weather activities. In some ways, it is a reboot of ILWS [International Living with a Star].” James F. Spann Jr., Senior Scientist, Office of Space Weather Observations, NOAA/NESDIS, “International Agency Space Weather Research and Mission Coordination Forum,” presented at the 45th Scientific Assembly of the Committee on Space Research (COSPAR), July 13–21, 2024, Busan, South Korea, https://www.cospar-assembly.org/uploads/documents/Finalprogram-2024.pdf.

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²² This paragraph was updated after the release of the report to reflect NOAA’s current space weather program.

Requirements Survey for Space Weather Products and Services report was published in 2019 (Abt Associates 2019). This report highlighted the specific needs of users in the electric power, satellite, and aviation sectors and emergency managers, as well as the diverse user base reliant on Global Navigation Satellite Systems (GNSS). Additional user surveys are being performed by the SWAG compliant with directives in the PROSWIFT Act. In September 2024, the SWAG published, “Results of the First National Survey of User Needs for Space Weather.”²³

E.A.2 Space Weather Benchmarking

The SWORM interagency task force released the Space Weather Phase 1 Benchmarks report in 2018. Following the report release, NSF and NASA requested that the Institute for Defense Analyses (IDA) make recommendations to improve the Phase 1 benchmarks, including identifying any outstanding gaps. This led to the release in 2019 of the “IDA Next Step Space Weather Benchmarks” document, written by a 32-member panel of experts chaired by Geoffrey Reeves (NSTC 2018).

The authors of the IDA document were divided into five working groups: geo-electric fields, ionizing radiation, ionospheric disturbances, solar radio bursts, and upper atmosphere expansion. The recommendations from these groups are detailed in the IDA report and include the following:

• Completing the national-scale magnetotelluric (MT) survey;
• Addressing gaps in the ionizing radiation species and energy ranges for which data are available;
• Taking new space-based observations with instruments at Earth–Sun L1 to measure solar energetic particles (SEPs) and with instruments in Earth orbit to measure SEPs and galactic cosmic rays (GCRs);
• Creating new benchmark quantities to better characterize ionospheric disturbances;
• Collecting solar radio data with continuous coverage of the Sun, with the necessary frequency coverage, frequency range, polarization, and dynamic range to determine high-fidelity benchmarks;
• Ensuring that future solar EUV observational missions have sufficient overlap to enable cross-calibration and have the spectral resolution needed for thermospheric modeling and forecasts; and
• For all subdisciplines, creating benchmarks, including statistical uncertainties, that characterize space weather events that occur more frequently than the more extreme 1-in-100-year events.

E.A.3 Quad-Agency Memorandum of Understanding (NASA, NSF, NOAA, Department of the Air Force)

In 2018, NASA, NOAA, and NSF signed a “Tri-Agency MOU,” facilitating the coordination of research topics in support of the National Space Weather Strategy. In December 2023, the Department of the Air Force joined in what is now referred to as a “Quad-Agency Memorandum of Agreement (MoA).” The MoA enables the agencies to coordinate and support efforts to facilitate the transition of space weather data and modeling capabilities to U.S. space weather prediction providers. It also facilitates feedback from prediction providers to the research community to improve research and operational forecasts.

E.A.4 Formation of the Space Weather Advisory Group

Composed of representatives from academia, the commercial space weather sector, and nongovernmental end users, the SWAG was established by the PROSWIFT Act to be an advisory body to the SWORM interagency working group. In 2023, SWAG delivered a report, “Findings and Recommendations to Successfully Implement PROSWIFT and Transform the National Space Weather Enterprise,” as an input to an upcoming update to the 2019 NSWSAP (SWAG 2023). In particular, the 2023 SWAG report,

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²³ “Results of the First National Survey of User Needs for Space Weather Product of the Space Weather Advisory Group,” 2024, https://www.weather.gov/media/nws/Results-of-the-First-National-Survey-of-User-Needs-for-Space-Weather-2024.pdf.

• directly enable key science in multiscale thermospheric coupling. Measurements of this caliber would also support coupled model development for the lower ITM, enabling studies/quantification of timescales for atmospheric driver impacts on, for example, satellite drag.
• PR2: (High) Neutral wind and temperature measurements are key to models of the coupled ionosphere–atmosphere system. BRAVO will specifically measure quantities sufficient to address conditions under which lower atmospheric processes can drive the thermospheric state (forcing from below). Na LiDAR measurements will provide vertical wave structure in neutral temperature, while the ground-based meteor radar network and TLS will provide bulk and local flow structures (meridional and zonal winds). Furthermore, the LiDAR and TLS can provide mean-state vertical resolution of neutral temperature, all keys to modeling the coupling of spatial and temporal scales (and coupling) in the neutral wind structure and energy.
• PR3: (Medium) Horizontal gravity wave field measurements from BRAVO will be provided by the three spacecraft in the central orbital plane. Sequential images from the three NIR cameras can be stitched together to map out the gravity wave field. These measurements are important for quantifying the spatiotemporal dependence of the lower atmosphere gravity wave momentum/energy flux incident on the ionosphere–thermosphere (in coordination with PR2).
• PR4: (Medium) Ionospheric electron density structuring via TEC maps (2D at assumed hFoF2, or 3D tomographic) are heavily utilized in various areas of global space weather research. BRAVO targets multiscale TEC measurements via ground-based global TEC maps, together with spacecraft GNSS RO measurements to give more local line-of-sight coverage (geometry dependent). The structuring of the electron density in the range 90–400 km (up to spacecraft altitude) can readily be utilized to model ionospheric structuring associated with thermospheric dynamics, or equally utilized in magnetosphere–ionosphere coupling to study forcing (from above) of ionospheric state. These measurements will be similar to existing GNSS RO (Spire, COSMIC, ePOP, etc.) and will enhance the number of available measurements (however, not dramatically with 5 spacecraft).

Value to Space Weather Operations

The primary value to space weather operations of the BRAVO mission is associated with thermospheric density and GNSS RO measurements, both of which couple to current nowcast products. The number of spacecraft and their configuration will not provide global information, but nonetheless could be readily available with ~90-minute latency to support relevant drag products or supplement global TEC relevant products.

• PO1: (High) Neutral-density measurements are operationally important for resident space object tracking—specifically, the propagation and prediction of orbital elements for collision assessments. Current operational models, such as NRLMSISE, are semi-empirical, relying on relatively simple algorithms, and are climatological in nature. BRAVO will provide Limb Sounders along three closely spaced orbital planes. With ~95-minute latency (assuming one download per orbit) the data would likely be useful for augmenting current model information as well as when combined with appropriate data assimilation model development. If integrated into an operational platform, this would be a significant step forward, adding support for data-driven augmentation to satellite drag calculations, a capacity that is not currently available.
• PO2: (Medium) GNSS RO measurements are theoretically readily integrated with other RO measurements (e.g., Spire, COSMIC-2) to provide data assimilation inputs to tropospheric/stratospheric and upper atmospheric/ionospheric numerical weather prediction models. BRAVO RO would enhance available data (number of RO profiles/day) for assimilative, operational models of the fully coupled atmospheric system. RO measurements can be inverted to provide TEC profiles in the ionosphere, which could contribute to operational assessments of ionospheric conditions for RF communications, over-the-horizon radars, and GNSS reception. With low-latency data retrieval, it is possible to provide key data that will enhance ionospheric nowcasting information for space weather operations.

auroral zone to facilitate the curlometer approach.) The satellites are phased to allow for the collection of in situ data from both hemispheres simultaneously. The LEO mission element characterizes the ionosphere–thermosphere via the magnetic field (at spacecraft via a magnetometer, and at ~80 km via the MEM instrument), plasma drift, electric field, atmospheric constituent densities (H, O, O₂, N₂, NO, and O⁺), oxygen temperatures, and local pitch angle–resolved energy spectra of precipitating electrons (10 eV to 30 keV).

Summary of instruments:

• HEO (2 spacecraft), each with
  • Multiband FUV Imager
  • Electron Spectrometer (10 eV to 30 keV)
  • Energetic Electron Detector (30 keV to 1 MeV)
• LEO (10 spacecraft), each with
  • Magnetic Field Instrument
  • Ion Velocity Meter
  • MEM Instrument (DC electric field)
  • Electric Field Probe (AC electric field)
  • FUV Spectrograph
  • THz Limb Sounder
  • Electron Spectrometer (10 eV to 30 keV)

Space Weather Value of the Mission as Proposed (Table E.B-4)

Value to Space Weather Research

The primary value to space weather research of the I-Circuit mission is associated with simultaneous sampling of precipitation (magnetospheric inputs) and ionosphere and thermosphere dynamics.

• PR1: (High) Global auroral imaging from a Molniya-like orbit would provide global maps of electron energy flux and characteristic energy, as well as provide key measurements of auroral boundaries. These measurements have been lacking since the days of Polar (2005) and Image (2008) and are sorely missed in the scientific community.
• PR2: (High) Neutral density measurements aboard 10 LEO platforms will enhance information about spatial and temporal scales of thermospheric density variations and enable key science in ionosphere–thermosphere coupling. The range of spatial scales accomplished via the four intersecting orbital planes have not been directly observed and are extremely important for multiscale coupling and drivers within the ITM system. Measurements of this caliber would also offer validation and assimilation data for coupled magnetospheric and ITM-system models, enabling, among other things, studies of driver impacts (atmospheric and magnetospheric) on LEO satellite drag.
• PR3: (Medium) Neutral wind and temperature measurements are key to models of the coupled ionosphere–atmosphere system. For example, these parameters are necessary to understanding the conditions under which lower-atmospheric processes can drive the thermospheric state (forcing from below) and under what conditions magnetospheric/ionospheric processes can drive thermospheric state (forcing from above), and the multiscale coupling between the two. I-Circuit measurements of the winds and temperature via the THz imagers will directly enable advancement of these topics by supplying data at a combined temporal and spatial resolution not sampled before. Furthermore, the direct measurements via the deployable “dropper” probes would give unique (direct) measurements of neutral winds. This will have value for space weather research via enhancing the physics of whole atmosphere models.
• PR4: (Medium) In situ plasma. Hot electron plasma (~10 keV) causes surface charging, and its altitude structure is not well known. Charging hazard may be particularly intense through the high-latitude auroral zone. Improved surface-charging plasma climatology models contribute to more efficient, robust spacecraft designs. Having the same measurements on the LEO and HEO spacecraft can potentially provide

• opportunities during HEO ascent and descent for coordinated studies of precipitation mechanisms and acceleration. Furthermore, the 600 km altitude, 10 spacecraft LEO mission segment will provide insight into the spatial scales of hot electron precipitation.
• PR5: (Medium) Current density in the region of current closure would provide extremely valuable data for coupling models of the IT system. These data would be new, as they sample scale sizes from a few tens of km to a few hundreds of km, a scale size not currently available for systematic studies of current structures. I-Circuit measurements would also be the first systematic, true measurements of the altitude variations of currents, providing key insights into mesoscale coupling of currents to the global system.

Value to Space Weather Operations

No real-time downlink is planned for the proposed mission in its current format. The high-altitude element would therefore be limited to a ~12-hour minimum latency (one orbital period), the LEO element on the order of 90 minutes, or less depending on number of downlink stations (based on con-ops plan of four orbital planes and spacecraft separation along orbital track).

• PO1: (High) Neutral-density measurements are operationally important for resident space object tracking—specifically, the propagation and prediction of orbital elements for collision assessments. Current operational models, such as NRLMSISE, are semi-empirical, relying on relatively simple algorithms, and are climatological in nature. I-Circuit will provide 10 Limb Sounders along four orbital planes. With ~95-minute latency (assuming one download per orbit) the data could be useful for augmenting current models when combined with appropriate model development. If integrated into an operational platform, this would be a tangible

• step forward, adding a data-driven augmentation to satellite drag calculations, a capacity that is not currently available.

Suggested Augmentation to the Mission to Enhance Its Space Weather Value

Value to Space Weather Research

• AR1: (Low) Add X-ray imager to high-altitude spacecraft.
  • X-rays are slightly more relevant for surface charging than UV.
  • Higher altitude complicates achieving valuable resolution.
  • Prior analog: Polar PIXIE (Polar Ionospheric X-ray Imaging Experiment).
  • Also consider including a visible imager (or higher-luminosity bands). This could enable higher-resolution and more detailed auroral images and data content. (See community input papers by M. Henderson [2022] on the need for better global auroral images and J. Rodriguez [2022] on continuous auroral imaging in FUV.)
• AR2: (Medium) Add energetic particle telescopes to all low-altitude spacecraft.
  • Hundreds keV to many MeV electrons and ions deposit considerable energy flux into the atmosphere and ionosphere systems; these ought not be neglected and are also relevant for spacecraft charging details in the proliferated LEO environment and the determination of particle cutoffs, which are used as an input to aviation radiation models.
  • Particle precipitation is also critical to the mission science.
• AR3: (Medium) Add energetic particle telescopes on high-altitude spacecraft to provide energy-resolved, differential intensities from more than one look direction.
  • Single-direction, integral fluxes are insufficient for their science and also relevant radiation environment (e.g., see HEO energetic particle observations: Fennell et al. 1997).

Value to Space Weather Operations

• AO1: (High) Addition of real-time downlink to two high-altitude spacecraft for space weather relevant data.
  • Near-real-time global auroral imagery of the northern hemisphere would improve/replace existing space weather operational systems (i.e., Ovation Prime). It would further allow development/demonstration of real-time auroral products (e.g., electron surface charging, scintillation probability maps, etc.).

E.B.3 Space Weather Contributions from the Comprehensive Observations of Magnetospheric Particle Acceleration, Sources, and Sinks (COMPASS) Mission

Mission Concept Summary

Comprehensive Observations of Magnetospheric Particle Acceleration, Sources, and Sinks (COMPASS) is a Large Strategic Science class mission. The goal of the mission is to explore the “heart” of Jupiter’s radiation belt region, a previously unexplored area, to understand how what may be the solar system’s greatest particle accelerator works. COMPASS consists of a single spacecraft launched on Falcon Heavy and uses an Earth gravity assist to reach Jupiter in approximately 6 years.

The COMPASS science payload consists of the following instruments:

• Thermal Plasma Detector (TPD): electrons and ions with composition from 10 eV/Q to 6 keV/Q.
• Suprathermal Particle Detector (SPD): ~3 keV/Q to 300 keV/Q ions with composition and charge state.
• Energetic Particle Detector (EPD): 25 keV to 1.5 MeV for electrons, 50 keV to >10 MeV for protons, and 150 keV to >10 MeV for O and S.
• Relativistic Particle Detector (RPD): 1.6 MeV to >19 MeV for electrons, 17 MeV to >100 MeV for protons.

• Ultra-Relativistic Particle Detector (UPD): 10 MeV to >50 MeV for electrons, >1 GeV for protons, >100 MeV/nuc for O and S.
• Fluxgate Magnetometer (FGM): DC magnetic fields from a few Hz to ~10 Hz.
• Search Coil Magnetometer (SCM): AC magnetic fields from 10 Hz to 20 kHz.
• Electric Field Waves (EFWs): AC electric fields from 50 Hz to 400 kHz.
• X-Ray Imager (XRI): X-ray photons from 0.5 to 5 keV.
• Education and Public Outreach Camera (EPOC): Not a science instrument (same as JunoCam from NASA’s Juno mission).

The proposed concept of operations for COMPASS is that during Earth gravity assist, radiation instruments will be cross-calibrated with other HSO components as well as checkouts during the cruise phase. Once the observatory reaches Jupiter’s orbit, it will complete several deep dives into the core radiation belt and synchrotron regions, including close flybys of the Jovian moons Io and Callisto. The mission lasts 514 days, completing 15 orbits, and ends with impact into Jupiter. The nine science instruments provide full energy range coverage of the charged particles, full spectrum wave measurements, the first X-ray imager in the Jovian environment, and a public outreach camera.

Space Weather Value of the Mission as Proposed (Table E.B-5)

Value to Space Weather Research

The main value to space weather research is understanding the extreme exposure of Jupiter’s harsh radiation environment.

• PR1: (Medium) Radiation belt conditions and effects. Jupiter’s radiation belts represent one of the most hazardous radiation environments in the solar system. Experience learned here on designing instruments to survive and monitoring their performance in this environment will help future spacecraft design and deployments throughout the solar system.

• [L1] ENA spectroscopic imager from 0.02–5 MeV
• [L1, L4] Photospheric vector magnetograph
• [L1] Lyman-alpha Hanle coronagraph from 1.1–3 R_☉ (descope option)

Space Weather Value of the Mission as Proposed (Table E.B-6)

Value to Space Weather Research

Like the Firefly and HELIX missions, the COMPLETE mission concept employs multiple spacecraft to obtain simultaneous multipoint measurements of the Sun. Its focus on understanding the mechanisms by which energy

is stored in the solar corona and impulsively released in the form of eruptions is well suited to supporting space weather research goals.

This evaluation is made on the version of the mission developed for the TRACE in which there are photospheric vector magnetographs on both the L1 and the L4 spacecraft, but only one coronal magnetic field measurement from the L1 spacecraft. The fact that this coronal magnetic field measurement is not on both spacecraft and is an apparent descope target makes the mission less compelling for space weather research because its primary discovery value lies in determining the 3D structure of pre-eruptive coronal magnetic field configurations. Descoping the coronal magnetic field measurement would eliminate its most important discovery potential and make this mission less appealing to space weather research.

The lack of any helioseismic investigation component of the mission also makes it less compelling for space weather research focused on better understanding and prediction of the solar activity cycle. While surface magnetic fields are the most visible manifestation of the solar cycle, measurement of subsurface flows from two vantage points in the ecliptic could provide valuable insights into the nature of the cyclic dynamo.

• PR1: (High) EUV imager, broadband spectroscopic imager, photospheric vector magnetograph. The range of instruments on COMPLETE that are dedicated to measuring magnetic energy storage and release in the solar corona ensures that it has the potential to significantly advance our understanding of solar eruptions, the root cause phenomenon behind all extreme space weather events.
• PR2: (High) EUV imager, photospheric vector magnetographs at L1 and L4. Off Sun–Earth line measurements of photospheric magnetic fields is of high value to space weather research because it enables tracking the evolution of active regions from the East limb to well beyond the West limb. Simultaneous EUV imaging, including from beyond the West limb, will enable identification of eruption events that are magnetically connected to Earth or to spacecraft in the Earth–Mars transit orbit.
• PR3: (High) EUV imaging and photospheric vector magnetic field measurements from L1 and L4 combined with coronal magnetic field measurements from L4. While a Ly-alpha spectropolarimeter has not been demonstrated for use in measurement of coronal magnetic field, and it is doubtful that a single instrument/viewpoint can reconstruct 3D coronal magnetic fields, a successful demonstration of this capability would likely open new avenues for observation and analysis of solar eruptions.
• PR4: (Low) γ-ray spectroscopic imager. Gamma-ray observations of solar eruptions were accomplished by the Compton and RHESSI observatories and are currently made by the Fermi Large Angle Telescope. These data have not proven useful to understanding or predicting solar activity, and this capability is thus rated as low value to space weather research.

Value to Space Weather Operations

The fact that COMPLETE would fly spacecraft only to the L1 and L4 Lagrangian points means that it will not be capable of full Sun observations. In particular, these two Lagrangian point spacecraft can measure magnetic field over only about 210 degrees in solar longitude, and they will not observe the polar latitudes. This lack of more complete solar observations makes the mission less compelling to space weather operations. Also, the lack of any coronagraphic imaging capabilities makes COMPLETE less useful in detecting and modeling large solar eruptions on, or just beyond, the West limb, which can be the most SEP-productive eruptions (at Earth or in cislunar space). Similarly, the lack of any solar wind or energetic particle detectors makes the mission significantly less valuable to space weather operations than the other multiview solar missions.

• PO1: (High) EUV imager, photospheric vector magnetographs at L1 and L4. The combination of two instruments with major relevance to space weather forecasting and nowcasting (EUV imager and photospheric magnetograph) at two locations with off Sun–Earth line observations from L4 makes the COMPLETE mission of high value to space weather operations. As noted, even higher value would have been achieved with coronagraph and in situ SEP instrumentation on board.

• events, coronal holes, and helioseismology studies. This provides observations needed to understand the interior of the Sun, such as rising magnetic fields of emerging active regions. These measurements are also immediately crucial to improve solar magnetic field and solar wind modeling, as the primary input to all solar wind models is the full-Sun photospheric magnetic field. Currently, models have to make rough assumptions on unobserved regions of the solar sphere, especially in the polar regions. Firefly provides measurements of both poles at the same time, and it will offer multipoint image evidence of the development of active regions and the evolution of solar eruptions. This is essential to improve

• predictive solar eruption and energetic particle models that currently lack reliability for regions more than 45-degrees circle on the center disk in the Sun–Earth line.
• Extreme Ultraviolet Imager (heritage STEREO) at both the poles and the ecliptic plane will help understand eruptions in all directions and improve CME source measurement and prediction of the arrivals of CMEs in deep space essential for deep-space exploration.

Value to Space Weather Operations

Firefly would provide continuous downlink beacon data for near-real-time space weather forecasting. The mission downlinks 6.4 GB of compressed data per day/per pair. The primary operational value of the low-latency data stream would be the daily full-Sun magnetic field measurements, including polar regions, that will significantly improve forecasting models of both background solar wind and CME propagation compared to current solar wind models, which use 27-day synoptic maps and extrapolated data for the polar and flux transport models for farside regions. CME observations from multiple viewpoints, including above the ecliptic, would add substantially to our

knowledge of CME formation, acceleration, and evolution, as well as feeding improved CME data to propagation models to significantly improve arrival time predictions at Earth or other planets such as Mars.

Downlinking this volume of data daily requires 10-hour passes with NASA’s Deep Space Network (DSN) 34 m ground stations for the ecliptic pair and polar pair. The science prime mission will last at least 4 years after final orbit insertion of the polar pair (10-year total mission duration).

Remote sensing: Having the multipoint magnetic field observations (from the poles and the ecliptic plane) will lead to the continuous assessment of the birth-to-death process of active regions needed to improve the modeling and predictive capabilities of solar eruptions that are the root cause of flares, CMEs, and solar energetic particle events. It will also improve synoptic measurements used as an input to operational solar wind models. Currently, solar magnetic field measurements are reliable only within 60 degrees of the disk center (as seen from Earth), thus greatly limiting our ability to drive predictive models of eruptions. Also, having coronagraph imaging from the poles at the same time from the ecliptic off the Sun–Earth line will improve the measurements for CME parameters, possibly decrease the lag time to get such parameters, and thereby improve CME arrival time estimates at Earth and other locations in the solar system such as Mars.

• PO1: (High/Medium) Polar and ecliptic magnetic field measurements. Having measurements on the active region development around the whole solar surface would increase the accuracy of models used for solar energetic particle forecasting and nowcasting. Note, with the Firefly mission CONOPS, these measurements are available only for ~2 months/year.
• PO2: (High/Medium) Improved analysis of coronal mass ejections and shocks. These near-real-time measurements are needed to understand the effects of the interaction of CMEs and solar wind HSS structures that significantly influence the arrival time at Earth and change the impact of such events with the geomagnetic storm characteristics. It will improve the current models used for CME arrival time forecasts (e.g., geomagnetic storm forecasting) and understanding and predicting SEP impacts at Earth (e.g., aviation industry), geospace (satellite industries), cislunar and Mars environments (e.g., astronaut health and single event upset, SEU, to vital exploration life-sustaining equipment) from CME driven shocks. It would serve as a proof of concept for the value of off Sun–Earth line observations made outside the ecliptic.
• PO3: (Medium) Near-real-time solar irradiance measurements. Ecliptic irradiance monitoring beyond L5 would give a longer 5- to 7-day advance forecast of EUV irradiance at Earth than that from L5 (3.5 days). Only a daily downlink of irradiance from the SPACECRAFT would probably suffice to update forecasts of thermospheric density, so NRT is not required.

In situ observations: The continuous in situ multipoint observations of solar energetic particles will improve current model predicting capabilities for warning time and peak intensity, and provide measurements needed to develop data assimilation models critical for future prediction capabilities for human deep-space exploration.

• PO5: (High) In situ energetic particle measurements. Add value of proton and heavy ion flux measurements and also electrons for SEP increase lead warning time. SEP composition is actually quite valuable information from a radiation perspective, because lighter elements and particles (ultimately electrons) can penetrate farther into materials/shielding/bodies at any given energy of interest, while heavier ions do more damage (more impactful on dose).

Suggested Augmentation to the Mission to Enhance Its Space Weather Value

Value to Space Weather Research

• AR1: (Low) Soft X-ray irradiance measurements.
  • 0.1–0.8 nm and 0.05–0.4 nm passbands (i.e., see GOES observations) enable identification of solar flare events and classification using NOAA/SWPC’s flare-class scale.

• • The X-ray instrument in the GOES/EXIS suite could be used for a cost estimate.
  • X-ray observations over the solar poles and off the Sun–Earth line would enable better understanding of active region and flare site evolution.
  • For additional cutting-edge research purposes, X-ray imaging and/or extension of passbands into the hard X-ray spectrum and finer sensitivity (than say RHESSI) would partially fill observational gaps in historic measurements that might enable advances in predictive capability.
• AR2: (Medium) Additional/different EUV passbands.
  • The Firefly HMCS specifies 171 and either 195 or 304Å as the two passbands in a single EUVI telescope.
  • 171 and 195Å images are both lower-temperature coronal plasma passbands and are therefore redundant. For one EUVI telescope, we suggest keeping the 195Å passband because it shows coronal holes more clearly than the 171Å passband and having 304Å as the second passband because it shows a chromosphere/transition region view of the atmosphere.
  • The panel suggests adding a second EUVI telescope with 131 and 94Å passbands. These passbands show hotter flare plasma and in combination with 195 and 304Å images from the first telescope could be used to classify the equivalent GOES X-ray magnitude of flares via established regression models.

Value to Space Weather Operations

• AO1: (High) Addition of X-band real-time downlink.
  • Real-time coronagraph data. Real-time coronagraph data from Firefly is rated as high value for space weather operations owing to the immediate improvement that observations from different vantage points, including the polar orbits, could make to forecast operations and, for example, the arrival time of CME forecasts.
  • Real-time magnetogram data. The advantages of having real-time magnetogram data off the Sun–Earth line and out of the ecliptic could show promise for improving models and forecasts but would need to go through a period of intercalibration with the Sun–Earth line magnetograms, development, demonstration, and validation, meaning that improvements would not be immediate.
  • Real-time EUV data. Real-time EUV data is rated as medium value to space weather operations owing to the additional situational awareness of solar activity from vantage points off the Sun–Earth line and out of the ecliptic. Use in operations could be achieved in the near future.
  • For a real-time downlink and telemetry augmentation to the Firefly mission, dedicated DSN service—or some equivalent for dedicated space weather telemetry streams from observatories in deep space—would need to be made available. Considering the high-demand and limited resources of the DSN, it may be problematic to rely on those ground stations. Furthermore, any Firefly data that would be made available for use in near-real-time analysis and/or modeling would need to properly account for speed-of-light time delay from Firefly in its distant, heliocentric orbits with respect to Earth.
• AO2: (Low) Soft X-ray intensity measurements. This could improve current models being tested operationally to support human exploration.
• AO3: (Low) Particle measurement up to 1 GeV/nuc. This is important to characterize galactic cosmic rays that have the highest chronic radiation impacts on space exploration systems and astronauts.

E.B.6 Space Weather Contributions from the HELIX Mission Concept

Mission Concept Summary

In their community paper submission to the decadal survey, Szabo et al. (2022) write:

The HELIX mission concept was originally developed in the NASA LWS Architecture Study (Cohen et al. 2022) and further studied by the JHU/APL mission design laboratory prior to submission as a community input paper to this decadal survey (Szabo et al. 2022). The HELIX constellation of seven spacecraft envisions a heliocentric orbit via a single launch, with a ~7.5-month orbit periodicity (1:1 resonance with Venus). A Venus encounter occurs after ~0.5 revolution about the Sun (roughly 3.7–5.7 months). A launch in 2032–2033 is assumed with C3 of ≤15 km²/s². Upon arrival at Venus, each spacecraft experiences a Venus gravity assist (VGA) that disperses the constellation into distinct science orbits. A single deterministic Venus spacing maneuver (VSM) is performed for most spacecraft 10–80 days after launch (optimal timing depends on the Venus transfer geometry) to enable a minimum time-spacing between each sequential Venus encounter. A “central” spacecraft in the constellation encounters Venus at the nominal epoch with no VSM required, while the other spacecraft are spaced away from the central spacecraft.

The TRACE process was performed on what was described as the “augmented” mission in the mission community input paper (Szabo et al. 2022). This report evaluates the TRACE mission profile:

On all seven spacecraft:

• Dual magnetometers
• Solar wind plasma and composition instrumentations
• Suprathermal ion and SEP detectors
• Radio waves and solar wind electron detection
• One remote sensing instrument on each spacecraft in the constellation choosing from the following list:
  • Photospheric magnetograph (3 spacecraft only)
  • Heliospheric Imager (3 spacecraft only)
  • EUV imager (1 spacecraft only)

There is no discussion in the HELIX community input paper summary on instrument data rates, or data volumes. The paper mentions that on-board storage of up to 1 week’s measurements is anticipated with associated weekly DSN downlinks. An X-band link is mentioned for lower-latency spacecraft housekeeping and orbital maneuver communications.

HELIX is envisioned as a Class C+ mission with an ELV-class launch vehicle (e.g., Falcon, Vulcan, New Glenn), and a 3-year primary mission that will make entirely new in situ measurements of solar wind and CME structure and SEP extent in the inner heliosphere. The remote sensing instrument suite would add the ability to image CMEs and possibly solar wind structures from novel viewpoints in the ecliptic plane upstream of the current or planned Lagrangian point orbit locations.

Space Weather Value of the Mission as Proposed (Table E.B-8)

Value to Space Weather Research

The primary value to space weather research of the HELIX mission as proposed lies in its ability to explore the in situ structure of CMEs and SEP events inside of 1 AU and off the Sun–Earth line, allowing, for the first time, a measurement of space weather-relevant quantities well upstream of Earth. This would increase our understanding of the inner heliospheric conditions and how they influence the acceleration, propagation, and evolution of dynamic space weather phenomena that impact Earth or space missions at other locations in the inner heliosphere. The remote sensing instruments add additional value given the constellation’s location off the Sun–Earth line (most of the time) and well inside the Earth–Sun L1 observation point.

• PR2: (High) Simultaneous multipoint SEP measurements.
  • Like the multipoint CME measurements described above, simultaneous multipoint in situ measurements of SEP fluence across a wide spatial domain would greatly increase our understanding of SEP acceleration, seed particle populations, and upstream conditions that are conducive to producing large SEP events. Comparison of upstream and post-shock passage from the various HELIX spacecraft in the inner heliosphere will be useful in characterizing the evolution of SEP events as they propagate outward to Earth and beyond. When the HELIX constellation is in the Sun–Earth line region, these measurements can be compared with measurements from L1, lunar, and geospace instruments to further elucidate how SEP events evolve as they transit the heliosphere, potentially leading to advances in our ability to predict SEP events with sufficient lead time to provide useable warnings to astronauts in interplanetary space or on the Moon or Mars.
• PR3: (High) Simultaneous multipoint solar wind measurements.
  • These measurements will contribute additional vantage points with which to validate solar wind models. With measurements from positions at smaller solar distances than L1 as well as off the Sun–Earth line, the evolution and spatial structure of the solar wind can be studied in greater detail. Such longitudinal and radial structure is critical for understanding the background solar wind into which CMEs and SEPs propagate which is known to have significant effects on the resulting severity of the associated space weather hazard at/near Earth as well as other locations of interest throughout the heliosphere, including Mars. The multipoint solar wind data would also be of value as assimilative proof-of-concept corrections to solar wind models that could enhance forecast accuracy in the future.

Value to Space Weather Operations

No real-time or near-real-time (NRT) beacon data downlink is planned for the proposed mission in its current format. As proposed, the mission is therefore not capable of providing inputs to real-time operations. The nominal prime mission length of 3 years is also too short to accumulate significant statistical information on SEP characteristics over the solar cycle. Thus, the mission as proposed does not offer any potential climatological or benchmarking contributions to space weather applications unless its lifetime is extended to at least one solar cycle. Tangible value to operations in the case of an NRT beacon would accrue from the following mission elements:

Remote sensing:

• NRT solar wind and CME measurements from non-Sun-Earth longitudes and well inside of the L1 point would offer valuable additional measurements to short-term forecasting of incoming space weather events as well as valuable nowcasting data during events to judge duration and All Clear conditions.

In situ:

• NRT multipoint SEP measurements would be of high value to short-term warnings and nowcasts of incoming radiation storms as well as to judge All Clear conditions at the conclusion of the storms.

Suggested Augmentation to the Mission to Enhance Its Space Weather Value

Value to Space Weather Research

• AR1: (Medium) Out-of-ecliptic observations from inclined orbit.
  • Adding an out-of-ecliptic spacecraft to the HELIX constellation would increase its value to space weather research because currently all measurements of solar wind, CME, and SEPs have been from the ecliptic. Solar Orbiter may achieve out-of-ecliptic measurements in the 2030 timeframe, but given its orbital perihelion radiation exposures, it remains to be seen if it will survive until that point.
• AR2: (Low) Increase SEP measurements to 1 GeV/nuc.
  • Extending the SEP measurements to 1 GeV/nuc would allow better characterization of not only extreme SEP events (including Ground-level Enhancement events), but also the GCRs in the inner heliosphere. Both of these have impacts on evaluating/designing satellites and planned astronaut activities.

applications, the long-term GCR observations from the ISP mission are potentially of value to future designers of spacecraft systems or mission planning operations.

• PA1: (Low) Long-term cosmic ray observations. Cosmic Ray Subsystem (CRS) measurements over the 50-year prime mission, and including multiple solar cycle variations, may be useful in refining future spacecraft designs and/or mission profiles, particularly in regard to human deep space mission planning and radiation risk assessments.

Suggested Augmentation to the Mission to Enhance Its Space Weather Value

There are no envisioned augmentations to the ISP mission that would enhance its value to space weather research or operations. However, the mission could potentially increase its benefit to space weather applications, in particular future deep space vehicle design, by augmenting its payload with a compact dosimeter instrument that would record total ionizing dose information throughout the mission profile as well as experiments to qualify and quantify long-term degradation and adverse effects during decades-long, deep-space operations.

• AA1: (Low) Long-term effects in deep space. Strategically located dosimeters to study the long-term degradation and adverse effects of extended (50 years) operations in deep space on specific spacecraft and instrument components.

E.B.8 Evaluation of the Lynx Mission Concept by the SWSA Panel

Mission Concept Summary

Lynx is intended as a mission in the largest-category class (~$2 billion, directed) to revolutionize our understanding of magnetospheric physics and magnetosphere–ionosphere coupling. Lynx is a combination of the Magnetospheric Constellation (MagCon) and the Plasma Acceleration, Reconfiguration, and Aurora Geospace Observation Network (PARAGON) mission concepts. The two mission concepts together combine an extensive constellation of in situ observatories (36 spacecraft in MagCon) with remote sensing observatories (3 spacecraft in PARAGON) to resolve for the first time mesoscale plasma transport and direct connections between in situ magnetospheric activity and structures and auroral activity and features.

The in situ component of Lynx (MagCon) consists of 36 small satellites distributed with 12 each along three different orbits. The three orbits were innovatively designed such that they all precess in local time at the same rate, enabling the constellation to stay together throughout the year (as Earth orbits the Sun) and for the duration of the prime mission. Periapses range from 1.1 to 1.5 R_E geocentric distance, and apoapses range from 8 to 15 R_E geocentric distance. The orbits are low-inclination, enabling observations from in and around the magnetic equatorial plane at low-magnetic-latitudes. All 36 spacecraft can be launched via the same launch vehicle (LV), because the observatories were designed to integrate to the LV using ESPA rings, which can be stacked one on top of another (i.e., 12 spacecraft per ESPA ring and a stack of 3 ESPA rings within the LV fairing). Each of the 36 in situ observatories incorporate a common payload of three instruments:

• Electrostatic analyzer (ESA) for in situ plasma distributions and moments
• Solid state telescopes (SSTs) for in situ energetic particle distributions
• Fluxgate magnetometer (FGM) for in situ magnetic field (DC to low-frequency waves)

The remote sensing component of Lynx (PARAGON) consists of 3 spacecraft spaced evenly (120 degrees apart in true anomaly) along a common, circular orbit of radius 9 R_E (geocentric). These observatories offer continuous observations of magnetospheric energetic neutral atom (ENA) images, extreme ultraviolet (EUV) imaging of the plasmasphere, and far ultraviolet (FUV) and optical imaging of the auroral ovals in both polar

hemispheres simultaneously. Each of the 3 remote sensing observatories incorporate a common payload of five instruments:

• ENA Narrow Angle Camera (ENA-NAC) for unprecedented spatial resolution in ENA imaging of magnetospheric plasma.
• ENA Wide Angle Camera (ENA-WAC) for global scale imaging of magnetospheric plasma.
• EUV imager for plasmaspheric imaging.
• FUV imager for high-resolution, global auroral imaging (day and nightside).
• Optical imager for high-resolution, global auroral imaging (nightside only).

By combining the PARAGON and MagCon concepts, Lynx promises to provide the revolutionary and unprecedented strategically distributed-multipoint, high-resolution, in situ and remote sensing observations necessary to resolve major outstanding questions in magnetospheric physics. Those outstanding questions to be addressed are fundamental to planetary magnetospheric plasma physics and concern the nature of mesoscale (i.e., between ion kinetic scales at <~1,000 km and global scales at ≥10 R_E) processes critical to substorm and storm-time activity, global magnetospheric convection and energy and mass transport, and magnetosphere–ionosphere coupling.

Space Weather Value of the Mission as Proposed (Table E.B-10)

Value to Space Weather Research

The benefits of the Lynx mission as proposed are extensive concerning space weather in Geospace. Even without a low-latency, continuous data link to ground for real-time space weather relevant telemetry streaming (see priorities below), the Lynx constellation will still provide critical observations directly relevant to multiple space weather environmental hazards in Geospace, particularly: auroral activity and intense current systems, substorm activity and spacecraft charging conditions, ring current evolution and geomagnetic storm activity, and radiation belt variability and radiation threats to human systems.

• PR1: (Medium to High) Lynx remote sensing observatories can provide observations of the auroral activity in both hemispheres simultaneously. Lynx observations and data will enable studies of what auroral features map back to magnetospheric processes and structures (i.e., they show up similarly in both hemispheres simultaneously) versus what auroral features are the result of local ionospheric processes (i.e., they show up in only one hemisphere), which is important information tracing to the development of improved models of auroral activity and related space weather effects and hazards. Auroral activity has been related to spacecraft surface charging hazards in the LEO environment (High priority), and the enhanced current systems associated with auroral activity can drive ground-induced currents (GICs) that pose a threat to power grid infrastructure (Medium priority). Space weather research may also benefit from studies using Lynx auroral observations to link auroral activity to the satellite charging environment in LEO or predictions of GIC conditions affecting the power grid.
  • Note: There is a new, advantageous aspect here considering coordination with geomagnetically induced current (GIC) and ground electric field (GEF) monitoring networks that were unavailable during the Polar and IMAGE mission eras.
• PR2: (Low to High) Lynx all together (in situ and remote sensing observatories) can provide observations of the energetic particle injection and localized flow burst environment in and around MEO, GEO, and low-latitude HEO. Resolving and characterizing “mesoscale” (i.e., between ion kinetic, ~10³ km, and global MHD, ~10⁵ km, scales in Earth’s magnetotail) plasma structures and dynamics in Earth’s magnetotail plasma sheet and inner magnetosphere is a major science objective of Lynx. Such dynamics include substorm activity like auroral enhancements, energetic particle injections, and fast (hundreds of km/s), localized flow bursts of hot plasma. Particle injections and plasma flow bursts are known to be important for and connected to internal (Low priority) and surface (High priority) spacecraft charging events and hazards. In particular, Lynx will enable space weather research important for developing

• conditional probabilistic nowcast/forecast models of the spacecraft charging environment in MEO, GEO, and HEO. Lynx observations will also provide data relevant to hindcasting and reanalysis modeling that can be used for spacecraft anomaly resolution.
  • Note: Simultaneous measurements enable development of low-to-high and high-to-low altitude models like SHELLS/PreMeVE, that allow us to fill in when we only have data from one location or the other.
• PR3: (Medium) Lynx in situ observatories can provide observations of the radiation belts nearly continuously. Earth’s radiation belts are an environmental hazard for robotic and crewed spacecraft and astronauts. The intensity and extent of the electron radiation belts are especially variable and difficult to

• predict. Frequent (≥1/hour) measurements of the radial distributions of radiation belt electron intensities (100 keV to several MeV) between ~1.1 R_E and ~8.0 R_E (geocentric distances) from low magnetic latitudes are required for characterizing the state of the electron radiation belts and their activity-dependent variability.
  • Note that for Lynx, such observations of Earth’s radiation belt electrons will drive requirements on SST performance and functionality considering background contamination, species differentiation, instrument dynamic ranges and sensitivity, and energy and angular ranges.

Value to Space Weather Operations

No real-time downlink is planned for the proposed mission in its current format. As proposed, the mission is therefore not capable of providing inputs to real-time nowcasting or forecasting operations. However, observations of the radiation and auroral environments can be used for development of benchmarks and as inputs for climatological models (e.g., IRENE radiation belt model), which engineers use routinely for space situational awareness, anomaly resolution, risk mitigation, and design constraints for satellite missions.

• PO1: (Medium) Lynx in situ observatories can provide observations of the radiation belts nearly continuously. Such observations (see more details on observational ranges above) are critical for developing benchmarks and climatological models plus space situational awareness and hindcasting models for satellite risk mitigation and anomaly resolution.

Suggested Augmentation to the Mission to Enhance Its Space Weather Value

Value to Space Weather Research

• AR1: (High) Addition of charge/discharge and radiation environment sensors on all spacecraft. Lynx orbits (both in situ and remote sensing observatories) transit multiple regions of concern for spacecraft charging hazards. Considering this, spacecraft charging data—such as charge/discharge sensors, electron intensities in the keV to 100s keV range, and/or spacecraft potential monitoring—would prove valuable for space weather research.

Value to Space Weather Operations

The benefits of an augmented Lynx mission to space weather operations are direct and clear. With the addition of a low-latency, continuous data link to ground for real-time space weather relevant telemetry streaming (see priorities below), the Lynx constellation could provide critical observations covering multiple space weather environmental hazards in Geospace, particularly: auroral activity and intense current systems, substorm activity and spacecraft charging conditions, ring current evolution and geomagnetic storm activity, and radiation belt variability and radiation threats to human systems.

• AO1: (High) Lynx can provide a communications relay network for continuous, low-latency (near-real-time) space weather data beaconing.
  • 3× remote sensing spacecraft ensure continuous coverage over the northern hemisphere, enabling continuous communications with a high-latitude station (e.g., in Alaska).
  • Remote sensing spacecraft are all 3-axis stabilized, making for straightforward approach to alignment/design of receiving antennas (for data streams incoming from in situ spacecraft and other space weather assets) and transceivers (for cross-link with each of the other two spacecraft and comm-link to ground).
  • Relay network can be used for Lynx RT stream and other (future) space weather assets in geospace.
  • Need to account for this up-front in the requirements and design of the telemetry budget and comm systems on the PARAGON spacecraft.
  • Consider this aspect for descope options on Lynx as a whole; all three PARAGON spacecraft would be needed to make this real-time relay network possible.

• • Potential for additional value and investment return via “Emerging Opportunities”: Laser communication cross-link (between 3 spacecraft) and downlink (each spacecraft to ground) could enable exceptional telemetry rates.

Remote sensing observatories: With the augmentation of a low-latency, continuous data link, the mission would provide full auroral oval monitoring in both hemispheres with the FUV and optical imagers and provide remote sensing observations of energetic particle injections from the magnetotail into the inner magnetosphere (including through GEO). Both of these are of high value from an operational space weather perspective.

• AO2: (High) Lynx can provide simultaneous auroral observations in both hemispheres. Such data are valuable for
  • Nowcast and hindcast capabilities concerning anomaly attribution and resolution informed by environmental conditions for spacecraft charging at LEO.
  • Nowcast capabilities concerning ionospheric current systems, GICs and power grid effects.
  • Nowcast capabilities concerning societal-interest and commercial value for auroral oval/sightings prediction.
• AO3: (High) Lynx can provide global observations of energetic particle injections plus localized and intense plasma flow bursts (spacecraft charging hazards at MEO, GEO, and HEO) from the magnetotail into the inner magnetosphere. Such data are valuable for improved benchmarking and climatological model development enabling systems’ risk mitigation through improved resilient design plus nowcast and hindcast capabilities for anomaly attribution and resolution concerning:
  • Storm-time ring current evolution, GICs, and power grid effects.
  • Space situational awareness (nowcast and hindcast) environmental conditions for spacecraft charging at MEO/GEO/HEO.

In situ observatories: The planned in situ observatory orbits will result in the spacecraft collectively spending large amounts of time (potentially continuously with at least one of the 36 spacecraft) in Earth’s radiation belts. With the augmentation of a low-latency, continuous data link and adequate instrument requirements for the energetic particle instruments, Lynx could provide near-continuous monitoring of radiation belt intensities throughout the inner magnetosphere.

• AO4: (Medium) Lynx can provide near-continuous observations of the variable intensity of Earth’s radiation belts. Such data are valuable for improved benchmarking and risk mitigation through climatological model development plus nowcast and hindcast capabilities for satellite anomaly attribution and resolution concerning:
  • Spacecraft charging.
  • Total ionizing and nonionizing dose.
  • Single event effects.

Achieving such monitoring drives performance and functionality requirements on the in situ SST instruments to enable these radiation belt measurements effectively considering background contamination, species differentiation, instrument dynamic ranges and sensitivity, and energy and angular ranges.

E.B.9 Space Weather Contributions from the Concept OHMIC Mission

Mission Concept Summary

The Observatory for Heteroscale Magnetosphere–Ionosphere Coupling (OHMIC) mission is a constellation of four spacecraft, 2× in situ and 2× imagers, targeting the auroral acceleration region (AAR) to determine how electromagnetic energy is converted into (charged) particle kinetic energy in Earth’s magnetosphere–ionosphere

system. OHMIC is proposed as a large-scale mission suitable for the current STP or LWS programs. The observatories combine global and local, high-resolution auroral imaging (UV wavelengths) with multipoint, in situ measurements of the local plasma, field, and wave conditions within the AAR to determine magnetospheric energy inputs and resultant heating and acceleration of ionospheric plasma, including ion outflow from the ionosphere back into the magnetosphere, an inherent systems-coupling process. The OHMIC mission can be implemented within 5 years, including Phase A.

The OHMIC constellation includes the following:

• Two spinning, in situ instrumented observatories (“Mother” and “Daughter”).
  • In the following orbits:
  • Mother: 500 km perigee × 6,000 km apogee (altitudes), 90-degree inclination, 160-minute orbit period.
  • Daughter: 1,000 km perigee × 5,500 km apogee (altitudes), 90-degree inclination, 160-minute orbit period.
  • And both with the following, identical scientific payload:
  • Auroral Plasma Instrument (API)—3D electron and ion distributions in energy from 1 eV–40 keV, with composition and angular resolution (i.e., pitch angle distributions).
  • Electromagnetic Fields Instrument (EFI)—3D electric and magnetic fields and waves, DC to 1 MHz (with fluxgate magnetometer, search-coil magnetometer, and 2× axial + 4× wire (spin plane) E-field booms), plus plasma density (Langmuir probe).
• Two 3-axis stabilized, imaging observatories (“Imaging-H” and “Imaging-L”).
  • In the following orbits:
  • Imaging-L: 500 km perigee × 6,000 km apogee, 90-degree inclination, 160-minute orbit period.
  • Imaging-H: 500 km perigee × 43,800 km apogee, 90-degree inclination, 800-minute orbit period (5× others’ periods; FOV from apogee covers full hemisphere of Earth).
  • And both with the following, identical scientific payload:
  • UVI–UV Imager LBHT (140–180 nm) and LBHL (160–180 nm), 8 degrees FOV, 0.03 degree angular resolution.

The Mother and Daughter in situ observatories provide detailed information on ionospheric outflow and magnetospheric energy inputs within the AAR. The Mother and Daughter are intentionally phased at different altitudes to provide simultaneous multipoint observations at two points along the same magnetic field lines.

Imaging-L and -H provide high-resolution, localized (-L) and global (-H) images of auroral activity, through which the Mother and Daughter observatories are measuring in situ plasma conditions.

Space Weather Value of the Mission as Proposed (Table E.B-11)

Value to Space Weather Research

As many of the sensors envisioned for OHMIC have past analogs, OHMIC provides new opportunities through simultaneous complementary measurement of relevant parameters, compared to past missions which had a sparser system of observations. Such observations contribute to knowledge of the state and evolution of the ionosphere–thermosphere system, particularly through the dynamic auroral zone and high latitudes, where spacecraft charging also represents a considerable space weather hazard.

• PR1: (High) In situ plasma. Hot electron plasma (~10 keV) causes surface charging and its altitude structure is not well known. Charging hazard may be particularly intense through the high-latitude auroral zone. Improved surface charging plasma climatology models contribute to more efficient, robust spacecraft designs. Pertains to OHMIC observatories Mother and Daughter, as proposed
• PR2: (Medium) Vector magnetic field data fills in some important spatial gaps. These data could readily be incorporated into empirical magnetic field models that are sometimes used operationally. The data could also be used for data assimilation and (in LEO) to constrain locations of FACs and electrojets (AMPERE). Pertains to OHMIC Mother/Daughter observatories.

• PR3: (Medium) Vector electric field measurements are used to constrain the polar cap potential and auroral convection, and can be used to improve empirical models which are then used by numerical simulations to improve representation of global magnetic and plasma configuration. Pertains to OHMIC Mother/Daughter observatories.

Value to Space Weather Operations

No real-time downlink is planned for the proposed mission in its current format. As proposed, the mission is therefore not capable of providing inputs to real-time operations, but as noted below OHMIC data can still be used for satellite operations, in those cases where data are still valuable up to 1–2 days after the fact.

• PO1: (Medium) Satellite anomaly resolution. For many satellite operators, anomaly resolution or forensics is the higher priority over forecast and nowcast. While anomaly triage can begin almost immediately after an event is detected, data coming in up to ~2 days after an anomaly can contribute to a decision to return