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Title page
Life on Mars?Modeling the subsurface radiation environment
Lewis DartnellCoMPLEX
University College London
Andrew Coates, MSSL John Ward, Biochemistry Laurent Desorgher, Bern
Mars today• 6 mbar atmosphere, freezing surface temperatures, bone-
dry surface sterilised by UV and cosmic radiation
Refugial Life
• Could extremophile life persist beneath the surface, within pockets of liquid water…?
• Deep hot Biosphere on Earth. • Methane plumes detected seeping out of
ground.
Secondary cascades
CGR primary produces extensive shower of secondary particles, with a core of hadrons (nuclear fragments, protons, neutrons) and pions within a spreading cone of the electromagnetic cascade (gamma and electrons) mediated by muon decay.
Pfotzer maximum in Earth’s atmosphere at an altitude of ~60,000ft
Flux diminished to ~1% at sea-level
Final Goal
• Which sites should we send our landers to?
• How deep would they
need to drill?
Coming up…• Persistence time of biomarkers• Optically-Stimulated Luminescence (OSL) dating• Lab work