Antonin Affholder's Avatar

Antonin Affholder

@aaffholder.bsky.social

Theoretical ecologist & biogeochemist. Astrobiology. Currenlty at the University of Arizona as a Post-Doc researcher. (Banner credits: https://www.nasa.gov/image-article/triple-crescents/)

42 Followers  |  69 Following  |  9 Posts  |  Joined: 20.11.2024  |  1.6913

Latest posts by aaffholder.bsky.social on Bluesky

Life in Titan’s Ocean? The Microscopic Possibility of Biomass on Saturn's Moon
YouTube video by SETI Institute Life in Titan’s Ocean? The Microscopic Possibility of Biomass on Saturn's Moon

Tonight I'll be on SETI Live, talking about our recent work about the habitability of Saturn's moon Titan ! Tune in at youtu.be/a8tgpFdHgWo

04.09.2025 10:42 — 👍 1    🔁 0    💬 0    📌 0
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2025 Cohort of the NOMIS-ETH Fellows The Centre for Origin and Prevalence of Life announces the 2025 cohort of NOMIS-ETH Fellows.

We are delighted to announce the 2025 cohort of NOMIS-ETH postdoctoral fellows. Thomas Drant and @aaffholder.bsky.social are joining the COPL, thanks to the generous support of the NOMIS Foundation.

copl.ethz.ch/news/COPL-ne...

@ethzurich.bsky.social @eth-eaps.bsky.social @usyseth.bsky.social

04.04.2025 08:28 — 👍 5    🔁 2    💬 0    📌 0
Interior Convection Regime, Host Star Luminosity, and Predicted Atmospheric CO2 Abundance in Terrestrial Exoplanets - IOPscienceSearchopens in new tab Interior Convection Regime, Host Star Luminosity, and Predicted Atmospheric CO2 Abundance in Terrestrial Exoplanets, Affholder, Antonin, Mazevet, Stéphane, Sauterey, Boris, Apai, Dániel, Ferrière, Rég...

(😅 of course I messed up with linking the paper : doi.org/10.3847/1538...)

13.02.2025 19:06 — 👍 0    🔁 0    💬 0    📌 0

Future directions include completing this coupled model with early-Earth type ecosystems in order to look at potential biosignatures and their detectability 😉. Will take time to do it right!


S Mazevet, D Apai @danielapai.bsky.social , B Sauterey, R Ferriere @regisferriere.bsky.social

13.02.2025 19:04 — 👍 0    🔁 0    💬 1    📌 0
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Taking a Bayes factor approach, we estimate that sampling ~25 exoplanets should allow us to answer this question. Target yields for near-future telescope designs are spot on to learn about exoplanet habitability 🎯.

13.02.2025 19:04 — 👍 1    🔁 0    💬 1    📌 0
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OK, but will future telescopes observing Earth-sized exoplanets in the HZ be able to determine which of our two scenarios is most common? How likely detection of atmospheric CO2 is differs between our scenarios.

13.02.2025 19:04 — 👍 0    🔁 0    💬 1    📌 0

Some amount of CO2 regulation occurs in planets in our SL scenario for carbon cycling... provided that they are relatively young (<2 billion yrs). SL is not as good for sustained habitability, but many terrestrial HZ planets could be habitable, even if in the SL regime!

13.02.2025 19:04 — 👍 0    🔁 0    💬 1    📌 0
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Lo and behold! The distributions of atmospheric CO2 as a function of orbit/luminosity are qualitatively different depending on the carbon cycle scenario (left: Earth-like; right:SL).

13.02.2025 19:04 — 👍 0    🔁 0    💬 1    📌 0
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To tackle this question, we tried to set expectations for the atmospheric composition of exoplanets under two scenarios of carbon cycling: Earth-like and 'stagnant-lid' (SL) where atmospheric control of CO2 is weaker. Writing and running this model has been my toughest challenge so far.

13.02.2025 19:04 — 👍 1    🔁 0    💬 1    📌 0
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We just got some new research published last week about exoplanet habitability : doi.org/10.3847/1538-3881/ada384
Earth's carbon cycle sustained by plate tectonics is unique in the solar system.
Are terrestrial exoplanets in the HZ like the Earth? Or like Mars and Venus ?

13.02.2025 19:04 — 👍 2    🔁 0    💬 1    📌 0

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