Create multiple orbiting balls

Hi there,

I'm looking to try and create multiple orbiting balls around a central sphere.

Here is an example of what I'm looking to do...

Each small ball is to orbit the central sphere following its coloured halo (these can stay viable as they are) and then drop behind to give it the orbiting effect.

I'm assuming each orbit needs to be individual movie clips and then need to be masked individually to achieve this effect.

Any help on doing this or pointing in the right direction will be amazing.

Thank you.