Is there an Effect that can take ~100 layers and "explode" them out from the center of the comp?

I have ~100 layers of atoms that are all collected around one bigger object in the center of the composition and I would like to have them slowly "release" or "explode" and disperse out to the outer portion of the composition. (for example, a big center ball has gravity and attracts 100 atoms, but then the gravity releases and the atoms disperse out).  I'm not sure what to even search for when looking to see if there's something like this. I would rather not have to go in and keyframe each one of the atoms. Any suggestion would be greatly appreciated. Thanks.