Aftermath of a collision with an ice giant

[AllanR]

Hi again.

Is it plausible that an ice giant like Neptune could be shattered by a collision such that it keeps a tight debris field for a few hundred thousand years before recoalescing as a planet?

In my story the characters hide in a debris field and refine the ices for fuel.

Also, if the planet shattering is plausible, could it be plausible that the collider gets captured by the host star in the same orbit (or close enough) as the destroyed planet, yet retrograde such the remnants of the ice giant and the remnants of the object that collided would interact twice in each of their years.

 

[anorlunda]

Except for the ice part, that sounds similar to the postulated formation of Earth's Moon. The debris field stayed in low Earth orbit for a long time before coalescing and before the orbital radius became so large.

It lacks only the collider part of your scenario. I'm guessing that nothing in orbital mechanics forces the collider body to leave the solar system.

 

[Nik_2213]

A possible 'gotcha': What happens to swirling debris without the planet core's magnetic field ? No magnetosphere to protect against solar flares, when could become a humungous 'comet' ?

Double-jeopardy: Is there an inner 'giant' whose magneto-tail may 'routinely' interact with the debris field ?
I can't find any reports of comets flaring when passing through Jupiter's magneto-tail, but several mentions that 'tail' is long enough to interact with Saturn when their orbital positions align every dozen or so years...

 

[Vanadium 50]

"Shattered" is difficult for something held together by gravity and not chemistry.

 

[DaveC426913]

A close pass by a Jupiter (domestic or rogue) could rip such a planet apart without needing an actual collision.