Modeling Solar Proton Event-induced Martian Surface Radiation Dose

GCR-induced secondary particles on the Martian surface at the Gale Crater modeled using GEANT4. Particle intensity, dI/dE (cm−2 sr−1 s −1MeV−1 ); e− (solid black), e + (red dotted), µ + (teal dashed), µ − (blue dashed). BON 10 model was used to calculate the incident GCR spectrum (O’Neill 2010).

Solar Proton Events (SPEs) can cause abrupt and significant enhancements to the Martian surface radiation dose.

Observations of the impact of SPEs on the Martian surface are available from satellites and surface detectors, but the data set is very limited in time, and the energy range is limited in scope, which makes it insufficient to estimate the impact of major events on the Martian surface.

On the other hand, long-term data of SPEs impacting the Earth spanning a large energy range is widely available, and can be used to estimate the impact of major events on Mars on long timescales. Herein, we take major SPEs observed during the past several decades on Earth (1956 - 2014), along with PAMELA observations (2006 - 2014) and use the GEANT4 Monte Carlo code to calculate the Martian surface radiation dose.

We study the contribution of proton fluence and spectral shape of events on the surface radiation dose and estimated the impact of possible major SPEs on the Martian surface in the future. These results have major implications for the planned human exploration of Mars. Overall we find that the radiation dose from extreme events can have a significant impact on astronaut health, and in rare, worst case scenarios, the estimated dose can even reach lethal levels.

Dimitra Atri, Caitlin MacArthur, Ian Dobbs-Dixon

Comments: Submitted
Subjects: Earth and Planetary Astrophysics (astro-ph.EP); Solar and Stellar Astrophysics (astro-ph.SR); Space Physics (
Cite as: arXiv:2012.00568 [astro-ph.EP] (or arXiv:2012.00568v1 [astro-ph.EP] for this version)
Submission history
From: Dimitra Atri
[v1] Tue, 1 Dec 2020 15:19:34 UTC (258 KB)

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