Geophysical & Astrophysical Fluid Dynamics Seminar Series

Title：Latest astrometric results for the Saturnian system

Speaker：Valery Lainey （Observatoire de Paris）

Location: Large conference room, 3rd floor

Time：9:30 am Jun 11, 2024 (Tue)

Tencent meeting: 677-120-308

Abstract: 

During the thirteen years spent in orbit around Saturn before its final plunge, the Cassini probe provided more than ten thousand astrometric observations of moons. Such a large amount of precise data has allowed us to search for extremely small signals in the orbital motion of the Saturnian satellites. These signals can be linked to key physical mechanisms at play in the system, opening the doors to a new vision of the Saturn system. Using more than a century of ground-based astrometric observations, and benefiting from Cassini imaging data, we have studied the orbital motion of all of Saturn's inner and main moons, including those recently discovered by the Cassini probe. We show how astrometry has allowed us to characterize the strong tidal effects acting among the Saturnian system, while assessing the interior characteristics of several moons and their primary, including the discovery of Mimas' ocean. Updated results are presented.

Short intro: 

Dr. Lainey is an astronomer at the Paris observatory and an expert in orbital dynamics of Solar system objects.  His first research topic was the Galilean satellites, for which he showed that Io was close to thermal equilibrium.  Then he lead the team that discovered the significance of tidal dissipation within Saturn and more recently the existence of the Mimas’ ocean.  During the years 2017-2019 he participated to the end of the Cassini mission at JPL (NASA).