Mars Atmospheric Isotopes: Insights into Past and Present Fractionation

Present-day Mars is inhospitable for life and cannot sustain liquid water on its surface. Yet, multiple lines of evidence suggest that in the past, different climatic conditions allowed liquid water to shape the surface and form minerals we observe today. Isotopic ratios in atmospheric species provide clues that changes in Mars’ climate may have been driven by atmospheric escape. Understanding the planet’s escape history, however, requires careful assessment of how heavy and light isotopes are lost to space.

Since March 2018, the ExoMars Trace Gas Orbiter has performed high-resolution solar occultation measurements, enabling, for the first time, detailed investigations of the vertical distribution of carbon, oxygen, and hydrogen isotopes in the Martian atmosphere. In this seminar, I will present key results from these studies, highlighting the atmospheric processes that impact isotope transport to the upper atmosphere and their eventual escape to space.

Fecha y lugar: 06/11/2025 – 12:30 | Salón de Actos
Juan Alday
Instituto de Astrofísica de Andalucía (IAA-CSIC)