With all these *new moons* now at Jupiter, how stable are their orbits? Will they orbit Jupiter for 4.5 Gyr period or much shorter time period?
My observation. Here is info on some of the moons and 100 Myr orbit stable. New Jupiter Satellites and Moon-Moon Collisions, https://arxiv.org/abs/1809.00700
, 03-Sep-2018. "We report the discovery of 12 new satellites of Jupiter, giving Jupiter 79 known satellites...A prograde-retrograde moon-moon collision between outer satellites of Jupiter has likely happened over the age of the solar system."
From the 4-page PDF, "The smallest satellites in the orbital groups are still abundant and not dispersed towards Jupiter. This suggests the collisions that created them occurred after the era of planet formation as significant gas and dust would preferentially drag the smaller satellites inward (Jewitt & Sheppard 2005)." My note, "after the era of planet formation", suggest many could be less than 4.5 Gyrs and more recent origin scenario(s), thus how long they have been orbiting Jupiter seems a good question.