Abstract: Unprecedented efforts from both the European and American space agencies are underway to find traces of ancient life on Mars (i.e., biosignatures). Two current NASA rover missions, an ESA/NASA rover mission launching in 2028, and the ambitious ESA/NASA Mars Sample Return effort that will bring Martian samples back to Earth in the next decade. However, the Martian surface is an extremely hostile environment, bathing in solar and cosmic radiation, so understanding how biosignatures degrade under radiation is crucial to increase our chances of detecting them on Mars. Here, I propose to study for the first time the radiation impact on biomolecules (serving here as analog biosignatures) from an anoxygenic microorganisms.

I will expose biosignatures, as well as living and dormant cultures to mimicked Martian surface conditions (pressure, temperature, atmosphere composition, radiation). To closely replicate the Martian radiation profile (coming both from the Sun and further cosmic sources), I will irradiate both with UV and ion radiation. This will provide complementary information on the chemistry of degradation and how it varies in different environments (living vs. dormant cells).

To measure the degradation rates and formation of byproducts, I will use both state-of-the-art laboratory instruments to have high-resolution data, as well as mission analog instruments currently present on Mars aboard NASA’s Perseverance rover, to have a dataset directly applicable for the mission teams (for data analysis and interpretation).

This project will be the first study to investigate the impacts of UV and ion irradiation on biosignatures from anoxygenic microorganisms with both laboratory and mission instruments. Several billion dollars are being invested by the ESA and NASA on missions to Mars to find biosignatures, and this study will help maximize the scientific return of those investments with direct application to international mission decisions and future mission design.

Martian.Radiation has received funding from the European Union's Horizon Europe research and innovation programme under grant agreement No 101276787.

Struttura INAF: Osservatorio Astrofisico di Arcetri (OAA)

PI INAF: Dr. Anaïs Roussel

Bando: HORIZON-MSCA-2025-PF

Riferimento contratto n. 101276787

Inizio: 3 giugno 2026

Durata: 24 mesi

Coordinamento: INAF