Gas planets with solid satellites

[Jordi H]

I assume that planets and their satellites are created more or less at the same time. Why gaseous planets like Saturn have solid rings and satellites?

 

[Bandersnatch]

Small bodies have too little gravity to hold on to volatiles. Once you have a large enough solid nucleus, and far enough from the star, it can start to accumulate the gasses.

 

[Jordi H]

Thank you. I did not know that the gaseous planets have solid nucleus.