Podcaster: Beth Johnson, Franck Marchis, and Simon Steel (alternate hosts); Guest: Dr. Valéry Lainey

Title: SETI Live –  The Mysterious Ocean of Saturn’s Moon, Mimas

Organization: SETI Institute



Recorded 8 February 2024.

Join us for an exciting SETI Live where we’ll explore the wonders beyond Earth. We’re excited to have Dr. Valéry Lainey, a renowned researcher from the Paris Observatory in France, as our guest. Dr. Franck Marchis, our Senior Astronomer, will be guiding the conversation, sharing insights from the universe. It’s set to be an engaging event, and we hope you’ll be part of it!

In a groundbreaking study published in Nature Journal, Valery Lainey and his team have unveiled a remarkable discovery about Saturn’s moon Mimas. Once thought to be a cold, solid body of ice and rock, Mimas now appears to harbor a vast global ocean beneath its icy crust. This revelation comes after a meticulous analysis of Mimas’s orbit, as observed by NASA’s Cassini spacecraft, which showed unexpected wobbles that suggest the presence of an under-ice ocean.

For years, the scientific community was skeptical about the possibility of an ocean within Mimas, mainly because the expected surface deformations were absent. However, Lainey’s research, based on recent simulations and precise orbital measurements, suggests that an ocean could exist without leaving visible marks on the moon’s surface. This finding not only reshapes our understanding of Mimas but also opens new avenues in the search for habitable environments beyond Earth. 

Bio: Beth Johnson is a communications specialist and social media manager with a degree in physics and master’s work in planetary science. She specializes in meteor showers, icy moons, and anything with volcanoes.

Franck Marchis is a senior planetary astronomer and chair of the exoplanet group at the Carl Sagan Center of the SETI Institute and Chief Scientific Officer and Founder at Unistellar. He has dedicated his work to the study of our solar system, specifically the search for asteroids with moons, using mainly ground-based telescopes equipped with adaptive optics.

Simon Steel is Deputy Director of the Carl Sagan Center for Research at the SETI Institute. As an observational astrophysicist, he specialized in optical spectrophotometry, with an interest in the star formation histories of galaxies.

Dr. Valéry Lainey, a renowned researcher from the Paris Observatory in France

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