P2 – Lunar Space Weather and its impact on the lunar surface, lunar environment and present and future exploration missions
Talks
P2 Wed 6/11 11:30-13:00, room Auditorium
Chairs: Fabrice Cipriani and Iannis Dandouras
(by session conveners)
Author(s): Drew L. Turner
Johns Hopkins Applied Physics Laboratory
Abstract: Every month, when we look up to the night sky and see a full moon, we can be quite certain that the Moon lies within Earth’s magnetotail, the extended portion of the anti-sunward magnetosphere that is elongated and drawn out by the solar wind. During its 27-day orbit, the Moon spends about 4-days transiting Earth’s magnetotail, where it is embedded within hot, tenuous magnetospheric plasma and an enhanced, yet time- and activity-dependent radiation and charging environment. Here, we present a very brief introduction and overview of the Moon in Earth’s magnetosphere, including critical details of eclipse, the lunar wake, and magnetotail activity, including substorms, plasmoids, plasma flow bursts, and intense and explosive enhancements of relativistic electrons. We present results from a series of ongoing, detailed statistical studies, several of which incorporate aspects of machine learning, to better characterize the impacts of Earth’s magnetospheric activity on the lunar environment. We next go on to describe the space weather impacts, consequences, and consideration of these phenomena at the Moon, particularly from the perspective of human spaceflight and the American endeavor to return to the Moon with the Artemis program.
Author(s): Luísa Santos, Rafael D. C. dos Santos, Luis Eduardo Antunes Vieira, Livia Ribeiro Alves, Alisson Dal Lago
National Institute for Space Research (INPE); National Institute for Space Research (INPE); National Institute for Space Research (INPE); National Institute for Space Research (INPE); National Institute for Space Research (INPE)
Abstract: This research examines the impact of solar energetic particles (SEPs) on lunar missions, which is crucial due to potential effects on equipment and human health. We analyzed data from the Lunar Reconnaissance Orbiter’s Cosmic Ray Telescope for the Effects of Radiation (CRaTER) to determine the impact of SEPs during May 2024, a period of intense solar flares. We compared these data with data from 2009 onwards. Our findings show a significant increase in SEP indices during May 2024, among the highest recorded, with distinct patterns similar to previous major solar events. Further analysis will include detailed SEP dose measurements and assessments of Linear Energy Transfer (LET) and flux. This highlights the necessity for sustained lunar SEP monitoring to ensure the success of future lunar missions.
Author(s): Bailiang Liu, Jingnan Guo, Yubao Wang, Mikhail Dobynde
University of Science and Technology of China; University of Science and Technology of China; University of Science and Technology of China; University of Science and Technology of China
Abstract: The Moon lacks a global magnetic field and atmosphere, leaving its surface been directly exposed to high-energy cosmic radiation. Sporadic Solar Particle Events are sources of a significant radiation exposure, potentially posing serious threats to the health of astronauts exploring the Moon. Generally, Solar Energetic Particles (SEPs) have a limited penetration capabilities (value needed), and associated radiation doses diminish significantly with increasing astronauts shielding. In this paper, we use the Radiation Environment and Dose at the Moon (REDMoon) model based on GEometry And Tracking (GEANT4) Monte-Carlo method to calculate the body effective dose induced by 262 large historical SEP events on the Moon under different shielding depths which can result from the lunar regolith shielding and/or additional aluminum shielding. We calculate and compare the contributions of SEPs within different energy ranges to the total body effective dose and carry out a statistical analysis based on the results from different SEP events. Additionally, we develop empirical functions to rapidly assess SEP-induced effective dose on the Moon under different shielding scenarios based on incoming SEP particle flux.
Author(s): Francesca E McDonald, Fabrice Cipriani, Iannis Dandouras, Patrick Fröhlich, Yoshifumi Futaana, Sylvain Ranvier, Hannah M. Sargeant, Veerle J. Sterken, Renee Weber, Laurentiu N. Daniel, James D. Carpenter
ESA, Netherlands; ESA, Netherlands; IRAP, France; IRS, Germany; IRF, Sweden; BIRA-IASB, Belgium; Uni. of Leicester, UK; ETHZ, Switzerland; NASA MSFC, USA; ESA, Netherlands; ESA, Netherlands
Abstract: Motivation: An Astronaut-deployed Lunar Environment Analysis Package (AstroLEAP) is being prepared as a potential European contribution to crewed landed missions (e.g., Artemis IV) [1-3]. AstroLEAP aims to provide in-situ analytical measurements to help understand the complex interactions and dynamics of the ‘dusty’ lunar surface with solar radiation, space plasma, energetic particles, meteoritic flux, and exosphere. Such measurements will help to characterise the associated physical mechanisms acting at the surface [e.g., 4-10] to constrain exploration environment models addressing both fundamental scientific questions and preparation for safe and sustained lunar surface operations [1-3]. Furthermore, AstroLEAP takes advantage of the Moon as a unique vantage point to characterise the Earth magnetosphere environments (magnetosheath, magnetotail lobes and plasma sheet) and upstream solar wind. A key design driver for the analysis package is the requirement for long duration (2-5 years) in situ surface operations, to understand the impact of temporally variable conditions on the environment dynamics, e.g., different illumination, solar wind flux, magnetospheric plasma populations (within and outside of the Earth’s magnetotail); solar events (e.g., CMEs, SEPs); meteoroid impacts, etc. [4-10].
AstroLEAP Facility: The complete facility shall thereby be composed of an analytical instrument suite supported by a payload servicing module providing long-term power, communications, power conversion and data storage/transfer. An international science team is working with ESA to prepare the science definition for informing facility development studies, including: a) Identifying and constraining prioritised objectives traceable to exploration science questions and challenges; b) Preparing science traceability matrices, including measurement performance capabilities, and deployment and functional requirements flown from the objectives; c) Elaborating science products and associated analytical techniques/ instrumentation that can be applied to address the identified measurements.
Findings: The findings, which draw on the expertise of the European research community within the fields of space weather and exploration environments, will be presented. These include:
A comprehensive review of the current environmental knowledge related to the lunar surface environments: Solar Wind and Magnetospheric plasmas, energetic particles (GCRs, SEPs, albedo energetic particles), interplanetary dust particles (IDP), interstellar dust (ISD), naturally mobilized dust populations, and exosphere, as well as near surface magnetic and electric fields, surface potentials, regolith electrical properties.
Human and Robotic Exploration enabling models, critical parameters and knowledge gaps.
Identification of potential measurements techniques and surface sensors enabling the characterisation of near-surface lunar environment and related observational constraints.
Opportunities: ESA science and development opportunities for AstroLEAP will ensue, including for the power servicing module development (2024); candidate instrument maturation (2024) and future science team opportunities.
References: [1] ESA Strategy for Science at the Moon (2019); [2] Artemis III SDT Report (2021); [3] ESA Explore 2040 (in prep.); [4] Dandouras et al. (2023) Front. Astro. Space Sci., 10: 1120302 ; [5] Grün et al. (2011) PSS, 59, 1672-1680 ; [6] Futaana et al. (2018) PSS, 156, 23-40 ; [7] Wurz et al. (2022) SSR, 218, 10 ; [8] Farrel et al. (2023) Min. & Geochem., 89, 563-609 ; [9] Denevi et al. (2023) Min. & Geochem., 89, 611-650 ; [10] Hurley et al. (2023) Min. & Geochem., 89, 787-827.
Author(s): Xin Wu
University of Geneva
Abstract: The LunPAN lunar orbital mission concept is one of the mission proposals recently selected for pre-Phase A studies by ESA through the Call “Small Missions for Exploration – Destination the Moon”.
The goal of LunPAN is to comprehensively map the lunar radiation field. LunPAN will cover the full range of GCR, SEP, and albedo charged particles, as well as albedo neutrons and gamma-rays. It will accurately measure the flux and composition of penetrating charged particles (100 MeV-10 GeV) with its main payload Pix.PAN, and energetic charged particles of 10 -100 MeV, as well as neutrons and gammas, with the smaller payload NeuPix, thus providing new and critical information on the lunar radiation environment for many scientific subjects, with primary sciences cases in the areas of GCR, SEP and space radiation, and secondary cases in lunar geology. LunPAN can use any lunar orbit, notably the low-maintenance NRHO that has been planned for the Lunar Gateway, although with a lower lunar orbit the albedo particle rates can be better measured, albeit with a higher orbit maintenance cost. The orbit optimization will be one of the main tasks of pre-Phase A studies.
Penetrating particles have not yet been precisely measured in deep space. This measurement gap will be filled by Pix.PAN, a compact magnetic spectrometer using thin and precise silicon pixel sensor optimized for energy measurement of penetrating particles. Pix.PAN builds on the Mini.PAN project funded EU H2020 grant, and has completed the Phase0/A/B1 studies with ESA’s “Ambitious Project for the Czech Republic” with the REMEC proposal, as well as completed the pre-Phase A studies with the COMPASS proposal, a mission to Jupiter’s radiation belts for a NASA call. It has also been selected by the SciSpaceE call “Reserve Pool of Science Activities for the Moon”. NeuPix uses the same pixel readout technology as Pix.PAN, but with innovative sensor+converter combinations to measure thermal and fast neutron fluxes and for gamma-ray spectroscopy, as well as for non-penetrating charged particles. LunPAN will also demonstrate innovative technologies for future deep space exploration.
Author(s): Lambropoulos Charalambos, Potiriadis Constantinos, Karafasoulis Konstantinos, Kazas Ioannis, Vourvoulakis John, Papadomanolaki Elena, Papangelis Alexandros
Aerospace Science and Technology Department, National and Kapodistrian University of Athens, Greece; Greek Atomic Energy Commission; Hellenic Army Academy; Institute of Nuclear and Particle Physics (INPP), NCSR Demokritos; Hellenic International University; Aerospace Science and Technology Department, National and Kapodistrian University of Athens, Greece; Aerospace Science and Technology Department, National and Kapodistrian University of Athens, Greece
Abstract: Moon is an auspicious environment for the study of Galactic cosmic rays (GCR) and Solar Particle Events (SEP) due to the absence of magnetic field and atmosphere. The secondary (albedo) radiation resulting from the interaction of the primary radiation with the lunar soil which consists mainly of gammas and neutrons can be exploited to study the soil composition. These characteristics raise the radiation risk for human presence in orbit around it or at the lunar surface. The LURAD instrument is designed with purpose to identify protons, ions, neutrons, gamma rays and electrons/positrons with good purity and efficiency, and measure their kinetic energy. The simulated detector response in the lunar radiation field shows the feasibility of: Proton and ion kinetic energy measurement up to 2 GeV/n. Energy measurement of gamma photons from 100 keV to 10 MeV. Neutron kinetic energy measurement from 100 keV to 300 MeV and of electrons/positrons from < 1MeV up to 20 MeV. No magnet is used, resulting in a low mass footprint. Kinetic energy determination well above 500 MeV/n is based on time-of-flight (ToF) measurements with the aid of fast scintillators. LURAD leverages on fully depleted Si monolithic active pixel sensors and on scintillators read by silicon photomultipliers. Fully depleted active pixel sensors use a deep implant existent in standard CMOS technologies as a charge collecting electrode of a reverse biased detecting diode formed with the high resistivity substrate. This implant isolates the transistor circuits built on its top from the substrate. We will present the design, simulation results and measurements of the various components of the detector as well as the challenges for its further development.
Posters
Posters I Display Tue 5/11 – Wed 6/11, room C1A – Aeminium
Authors in attendance: Tue 5/11 10:15–11:30, 15:15-16:15; Wed 6/11 10:15–11:30
Author(s): Matheus A. Tunes, Sandra Veronica Gonzaga Hernandez, Patrick Willenshofer, Sebastian Samberger, Thomas M. Kremmer, Philip Aster, Andreas Weidinger, Irmgard Weissensteiner, Florian Schmid, Lukas Stemper, Diego Coradini, Ramona Tosone, Peter Uggowitzer, Stefan Pogatscher
Montanuniversität Leoben, Austria; Montanuniversität Leoben, Austria; Montanuniversität Leoben, Austria; Montanuniversität Leoben, Austria; Montanuniversität Leoben, Austria; Montanuniversität Leoben, Austria; Montanuniversität Leoben, Austria; Montanuniversität Leoben, Austria; AMAG Austria Metall GmbH, Austria; AMAG Austria Metall GmbH, Austria; AMAG Austria Metall GmbH, Austria; AMAG Austria Metall GmbH, Austria; ETH Zürich, Switzerland; Montanuniversität Leoben, Austria
Abstract: Aluminium and its alloys are pivotal in advancing human space exploration. These materials are ideally suited for aerospace applications due to their exceptional strength-to-weight ratio and robust performance under thermal cycling, plasma, and corrosive environments. Aluminium is universally recognized as a strategic material across all space programs, providing essential radiation shielding for spacecraft and satellites as well as to ensure the safety of human crews. Recent global initiatives aimed at establishing permanent human settlements on extraterrestrial environments like the Moon and Mars present novel challenges for the use of aluminium alloys in space environments. Prolonged exposure to the cumulative dose of the complex radiation scenario of space can rapidly degrade aluminium alloys, compromising their structural integrity and diminishing their effectiveness as radiation shields. In this presentation, we will introduce a new generation of European-designed aluminium alloys, termed “aluminium crossover alloys”, specifically developed to offer enhanced radiation resistance for space applications. Recent irradiation tests in simulated environments extrapolating the aggressive irradiation flux commonly found in space indicate these new aluminium crossover alloys outperform existing commercial aluminium alloys. New ideas towards heterogenous alloy design to offer simultaneous proton irradiation resistance and neutron shielding will be for the first-time introduced.
Author(s): Sigiava Aminalragia-Giamini, Hugh Evans, Piers Jiggens, Daniel Matthiä, Ingmar Sangberg, Constantinos Papadimitriou, Ioannis A. Daglis, Georgios Balasis
SPARC; ESA-ESTEC; ESA-ESTEC; German Aerospace Center (DLR); SPARC; SPARC; National and Kapodistrian University of Athens; National Observatory of Athens
Abstract: A Standard Radiation Environment Monitor (SREM) unit will be part of the European Radiation Sensors Array (ERSA) payload for the Lunar Gateway. This SREM unit will provide measurements of the lunar particle radiation environment, which is primarily dominated by Solar Energetic Particle (SEP) events and Galactic Cosmic Rays (GCRs). We present results from a novel analysis of SREM measurements from the INTEGRAL, PLANCK, and HERSCHEL missions, which span in total almost three decades. We have adapted and applied an existing artificial intelligence unfolding method (GenCORUM) to derive high quality particle fluxes during SEP events, and it is shown that we can successfully and concurrently derive solar proton and solar electron fluxes. Solar protons are resolved at a much higher energy than previously possible, up to 1 GeV, while solar electrons, which have not been previously resolved, are derived in the energy range of 0.5 MeV – 4 MeV. Additionally, we show that SREM directly measures GCR particle fluxes, which fully determine its “background” levels with a non-negligible contribution from heavy ions (Z≥2). Using appropriate GCR models we have also resolved GCR fluxes directly from SREM measurements covering a large energy range from 10 MeV/nuc to 100 GeV/nuc, something which has also not been done before. Finally we present elements on the new historical datasets created and the real-time applicability of our approach for ERSA/SREM. Successful validations of our results are shown by comparisons with the SEPEM RDS proton dataset, electron data from ACE/EPAM, and SOHO/EPHIN, as well as established models and data for GCRs.
This work has received funding from the European Space Agency under the “Unified Interplanetary & SPE modelling (FIRESPELL)” activity under ESA Contract No. 4000142510/23/NL/CRS and from the European Union’s Horizon Europe programme through SPEARHEAD project under grant agreement No 101135044
Author(s): Zachary Yokley, Drew Turner, David Lawrence, Patrick Peplowski, Jack Wilson
JHU-APL; JHU-APL; JHU-APL; JHU-APL; JHU-APL
Abstract: The lunar surface is continuously irradiated by galactic cosmic ray (GCR) and solar energetic particle (SEP) protons which modify the regolith and produce a spectrum of secondary particles. A principal concern for future exploration is the variation of this incident flux and the dose incurred from the secondary particles, particularly albedo neutrons [1]. Previous measurements of lunar albedo neutrons were focused on geochemical investigations and relied on proxies for the GCR flux (see for example [2]), and the CRaTER instrument on the Lunar Reconnaissance Orbiter is sampling the GCR environment [3]. Combining these in a single package has been recently highlighted as a gap by the space weather community [1].
The Site-agnostic Energetic Lunar Ion and Neutron Environment (SELINE) is an instrument suite concept currently under development at the Johns Hopkins University – Applied Physics Lab (APL) that will have the capability to measure energetic particles, albedo neutrons, and ionizing dose on the lunar surface. This poster will describe the details of the SELINE suite, its use cases for a lunar space weather and dosimetry station, and instrument models in the lunar radiation environment.[1] Vourlidas, A., et al., (2021) “Space Weather Science and Observation Gap Analysis for NASA.”[2] Feldman W. C., et al., (1998), Science 28, 1489.[3] Looper, M., et al., (2020), Space Weather, 18, e2020SW002543.
Author(s): Iannis Dandouras, Matt G. G. T. Taylor, Johan de Keyser, Yoshifumi Futaana, Elias Roussos, Pierre Devoto, Julien Forest, Arnaud Trouche, Sébastien L. G. Hess, Jean-Charles Mateo-Vélez
Institut de Recherche en Astrophysique et Planétologie, Université de Toulouse / CNRS / UPS / CNES, Toulouse, France; ESTEC / ESA, Noordwijk, The Netherlands; Royal Belgian Institute for Space Aeronomy, Brussels, Belgium; Swedish Institute of Space Physics, Kiruna, Sweden; Max Planck Institute for Solar System Research, Göttingen, Germany; Institut de Recherche en Astrophysique et Planétologie, Université de Toulouse / CNRS / UPS / CNES, Toulouse, France; Artenum, Ramonville Saint-Agne, France; Artenum, Ramonville Saint-Agne, France; ONERA – The French Aerospace Lab, Toulouse, France; ONERA – The French Aerospace Lab, Toulouse, France
Abstract: The Lunar Orbital Platform – Gateway is a versatile space station that will be assembled in orbit around the Moon in support of lunar activities, including the Artemis missions to return humans to the Moon. The Gateway will constitute also a platform for fundamental and applied scientific research in several disciplines.
The Moon and its environment constitute a unique natural laboratory for the study of the deep space plasma and planetary space weather. During most part of its orbit around the Earth the Moon is directly exposed to the solar wind. Due to the absence of a substantial intrinsic magnetic field and of a collisional atmosphere, solar wind and solar energetic particles (SEPs) bombard its surface, interacting with the lunar regolith and the tenuous lunar exosphere. The same phenomenon occurs also with the galactic cosmic rays (GCRs). However, 5 – 6 days each orbit the Moon crosses the tail of the terrestrial magnetosphere facilitating the in-situ study of the terrestrial magnetotail plasma environment. When the Moon is again outside of the magnetosphere, solar-terrestrial relationships can be investigated through remote sensing using a variety of imaging techniques. The lunar environment is thus a unique natural laboratory for the study the interaction of the solar wind and the magnetosphere with the lunar surface and the lunar surface-bounded exosphere.
In preparation of the scientific payload of the Lunar Orbiting Platform – Gateway Phase 2 (late 2020s), we undertook for ESA a conceptual design study for a Space Plasma Physics Payload Package onboard the Gateway (SP4GATEWAY). The main goal of this study has been to provide first a science rationale for hosting space plasma physics and space weather instrumentation on the Gateway, and then to proceed to a conceptual payload design addressing these objectives and compatible with the technical requirements. The Gateway modules that are best-suited for placing there the in-situ measurement plasma instruments have been identified following a simulation we performed of the interaction between the Gateway and its plasma environment. It appears that the Gateway is well-suited for space plasma physics research and planetary space weather monitoring.
Author(s): Fabrice Cipriani, Cecilie Holmen
European Space Agency; European Space Agency
Abstract: The Lunar Surface, while exposed to different plasma and radiation regimes along its orbit around Earth, is also encountering rapidly varying conditions during solar storms, leading to CMEs crossing, EUV and X-rays fluxes changes or perturbed magnetospheric conditions. In addition, lunar surface topography and illumination changes lead to a variety of interactions between the surface and the local plasma, whereby local slopes, regolith coverage and shadowing effects strongly determine surface and volume potential gradients, as well as near surface electrons, ions, dust densities and temperatures.
In the current context of designing and implementing missions to the Moon, ESA requires to specify lunar surface conditions and their variabilities to both constrain design choices regarding environmental risk and allow for smooth operations of surface assets, vehicles and exploration systems, such as landers, rovers, astronauts and eventually lunar habitats.
In this context, the current study presents an assessment of surface charging of potential locations of interest for exploration missions under study at ESA, when subject to varying illumination and plasma environments, including the occurrence of Space Weather events. A review of current lunar plasma environments specifications as defined for the ARTEMIS program and applied to e.g. ESA Gateway elements in lunar orbit was performed to select the most appropriate and representative conditions at the lunar surface. These include min, average and max upstream Solar Wind, Solar Wind wake, Magnetospheath dayside and wake, magnetotail lobes and plasmasheet environments, as well as specific CME events. Potential maps as well as plasma and dust populations densities and temperatures, and their variability range, will be presented for the sites of interest. In addition, implications for carrying lunar science measurements locally will be discussed.
Author(s): Chris Watson, Giacomo Radaelli, PT Jayachandran, Anton Kashcheyev, David R. Themens, Richard B. Langley, Richard Marchand, Andrew Yau
University of New Brunswick; Ecole Nationale d’Aviation Civile; University of New Brunswick; University of New Brunswick; University of New Brunswick; University of Birmingham; University of New Brunswick; University of New Brunswick; University of Alberta; University of Calgary
Abstract: The lunar ionosphere is a thin layer of electrically charged plasma surrounding the moon, and was identified as one of eight key areas of focus for lunar science by the United States National Research Council in “The Scientific Context for Exploration of the Moon”. While the existence of the lunar ionosphere has been established for decades, its structure, dynamic behaviour, and formation mechanisms remain unresolved due to extremely limited observational capacity and significant discrepancies in existing results. An enhanced observational picture of the lunar ionosphere and improved understanding of its formation/loss mechanisms is critical for understanding the lunar environment as a whole and assessing potential safety and economic hazards associated with lunar exploration and habitation. To address the high priority need for observations of the electrically charged constituents near the lunar surface, we introduce a concept study for the Radio Instrument Package for Lunar Ionospheric Observation (RIPLIO). RIPLIO would consist of a multi-CubeSat constellation (at least two satellites) in lunar orbit for the purpose of conducting “crosslink” radio occultation measurements of the lunar ionosphere, with at least one satellite carrying a very high frequency (VHF) transmitter broadcasting at multiple frequencies, and at least one satellite flying a broadband receiver to monitor transmitting satellites. Radio occultations intermittently occur when satellite-to-satellite signals cross through the lunar ionosphere, and the resulting phase perturbations of VHF signals may be analyzed to infer the ionosphere electron content and high- resolution vertical electron density profiles. This concept study presents preliminary simulations of crosslink lunar radio occultations, in addition to preliminary system and operational requirements for a potential RIPLIO mission. As demonstrated in this study, RIPLIO would provide a novel means for lunar observation, with the potential to provide long-term, high-resolution observations of the lunar ionosphere with unprecedented pan-lunar detail.
Author(s): Neophytos Messios, Erwin De Donder
Royal Belgian Institute for Space Aeronomy (BIRA-IASB); Royal Belgian Institute for Space Aeronomy (BIRA-IASB)
Abstract: ESA’s SPace ENVironment Information System (SPENVIS) provides interfaces to various models and tools that can be utilised for scientific studies related to the characterisation of the space environment and its effects. With the renewed interest in lunar exploration more and more users are employing the system to simulate potential missions to the Moon.
Currently, SPENVIS does not have a separate option for lunar missions since there are no dedicated space environment models for the Moon available in the system. However, one can still use it to perform radiation analysis for such missions. We present here some general guidelines for setting up a complete lunar mission and characterising the encountered radiation environments due to Galactic Cosmic Rays (GCR), Solar Energetic Particles (SEP) but also trapped particles. The latter is particularly important if the spacecraft is crossing slowly the Earth’s radiation belts on its way to the Moon. Furthermore, SPENVIS can be used to set up simulations in order to study the lunar albedo secondary particles generated from the interaction of incident high-energy particles with the lunar soil. As an example, we present some work done in support of the design of a miniature X-Ray Fluorescence (XRF) spectrometer for a future ESA mission to the Moon.
Finally, we welcome any comments and suggestions that could help us improve the SPENVIS capabilities facilitating the planning of lunar missions.
Author(s): Shaowen Hu, Janet E. Barzilla, Marlon Núñez, Edward Semones
KBR, Houston, TX, USA; Leidos, Houston, TX, USA; Department of Languages and Computer Sciences, Universidad de Málaga, 29016 Malaga, Spain; NASA Johnson Space Center, Houston, TX, USA
Abstract: As large solar energetic particle (SEP) events can add significant radiation dose to astronauts in a short period of time and even induce acute clinical responses during missions, they present a concern for manned space flight operation. To assist the operations team in modeling and monitoring organ doses and any possible acute radiation-induced risks to astronauts during SEP events in real time, ARRT (Acute Radiation Risks Tool) 1.0 has been developed and successfully tested for Artemis I mission. The ARRT 2.0 described in this work integrates an established SEP forecasting model – UMASEP-100, further enabling real-time dose prediction for the upcoming Artemis II and following missions. With the new module linking with UMASEP-100 outputs in real time, the total BFO doses of most significant events can be communicated at the time of onset and hours before the peak. This is based on a flux-dose formula identified from comparing UMASEP-100 results with transport calculation for the events during 1994-2013 and validated with events outside that period. ARRT 2.0 also shows capability to distinguish minor events from significant ones to screen false alarms that will cause disruptions for space activities. This improvement provides additional information for operational teams to make timely decisions in contingent scenarios of severe SEP events to mitigate radiation exposure.