Mimas, una delle lune di Saturno, potrebbe ospitare un oceano sotto la crosta ghiacciata. La ricerca si basa sui dati raccolti dalla sonda Cassini.
Articolo con breve riassunto della notizia:
Valéry Lainey at the Paris Observatory in France and his colleagues analysed observations of Mimas’s orbit made by NASA’s Cassini spacecraft. They found that its orbit around Saturn has drifted around 10 kilometres over 13 years. According to the team’s calculations, this orbital drift could only have been produced by wobbles from an icy shell sliding over an ocean, or a core with a physically impossible pancake shape.
Video con gli autori della ricerca.
We’re excited to have Valery Lainey, a renowned researcher from the Paris Observatory in France, as our guest. Franck Marchis, our Senior Astronomer, will be guiding the conversation, sharing insights from the universe.
Ricerca su Nature.
Here, from detailed analysis of Mimas’s orbital motion based on Cassini data, with a particular focus on Mimas’s periapsis drift, we show that its heavily cratered icy shell hides a global ocean, at a depth of 20–30 kilometres. Eccentricity damping implies that the ocean is likely to be less than 25 million years old and still evolving. Our simulations show that the ocean–ice interface reached a depth of less than 30 kilometres only recently (less than 2–3 million years ago), a time span too short for signs of activity at Mimas’s surface to have appeared.
- A recently formed ocean inside Saturn’s moon Mimas
https://www.nature.com/articles/s41586-023-06975-9.epdf