11:00 〜 11:15
[PPS01-08] Constraints on the Formation of Large Icy Moons from Gravity Field Measurements by Space Missions
キーワード：氷衛星、ペブル集積、内部構造、JUICE、Europa Clipper
Although many formation scenarios for the large icy moons around Jupiter and Saturn have been proposed, none of them has been universally accepted as the true history of their formation. One possible clue to solving this problem is revealing the internal structures of these moons.
For example, Callisto is estimated to have an only partially differentiated internal structure, based on measurements of its gravitational field by the Galileo mission. This suggests a slow accretion process for the moon's material. More detailed measurements of the gravity fields of the Galilean moons by the JUICE and Europa Clipper missions will further constrain their formation scenarios.
In particular, the pebble accretion scenario, which has been the subject of recent studies, could allow the moons to form without full differentiation. In this talk, I will compare the thermal conditions of the interiors of forming moons under two formation scenarios: the recent pebble accretion model and the classical satellitesimal accretion model. If future missions confirm that pebble accretion played a role in the formation of icy moons, this could provide the first evidence of pebble accretion—a process that has not yet been directly confirmed, even in the context of planet formation.
For example, Callisto is estimated to have an only partially differentiated internal structure, based on measurements of its gravitational field by the Galileo mission. This suggests a slow accretion process for the moon's material. More detailed measurements of the gravity fields of the Galilean moons by the JUICE and Europa Clipper missions will further constrain their formation scenarios.
In particular, the pebble accretion scenario, which has been the subject of recent studies, could allow the moons to form without full differentiation. In this talk, I will compare the thermal conditions of the interiors of forming moons under two formation scenarios: the recent pebble accretion model and the classical satellitesimal accretion model. If future missions confirm that pebble accretion played a role in the formation of icy moons, this could provide the first evidence of pebble accretion—a process that has not yet been directly confirmed, even in the context of planet formation.