Move over, Saturn: Jupiter is the solar system's new 'moon master'

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."

https://arxiv.org/pdf/1809.00700.pdf

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.
 
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Feb 4, 2023
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I'm pretty sure Jupiter can't "boast", and all those moons have been there the whole time.
Exactly. It's rather ridiculous to announce that Jupiter now has more moons but later will have less (than Saturn). You're referring to the vagaries of human counting, not the actual number of "moons" that will remain consistent. So that braggart Jupiter is boasting through his-her-their hat!
 
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What's the difference between a moon and a mere rock? Apparently there's no official definition of a moon, including size, so I guess that all the gas giants have endless "moons" waiting to be discovered.
 
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What's the difference between a moon and a mere rock? Apparently there's no official definition of a moon, including size, so I guess that all the gas giants have endless "moons" waiting to be discovered.
My sentiments exactly. We need a definition of "moon" that doesn't include every rock in orbit around a planet. After all, how many "moons" are in Saturn's rings?
 
What's the difference between a moon and a mere rock? Apparently there's no official definition of a moon, including size, so I guess that all the gas giants have endless "moons" waiting to be discovered.
Yes, there is no official definition as far as size or structure.

I suspect a definition might eventually include a diameter as small as 1 km. This is the smallest diameter I see for the list of Jupiter's moons and Saturn's moons. Smaller objects might be called "moonlets".

Since they are being called moons now, then it will be more difficult to change this common use. Pluto demotion was traumatic as many wanted it grandfathered given its common label as a planet.

On the other hand, there are over 1 million asteroids greater than 1 km in size. Only about 200 asteroids 100km in size.