Ok so the universe is expanding, so how fast is the solar system expanding outward then?

Question

Also if the solar system is expanding how much closer would Mars be to Earth say 500 million years ago?

Answer 1

It's not. On a local scale ('local' being about the size of a group of galaxies in this case) gravity overpowers the expansion of the universe. So that's why galaxies don't fly apart, and the Andromeda galaxy is actually coming towards the Milky Way.

If you were sitting on a big trampoline that was being stretched in all directions, it wouldn't rip you apart - the electromagnetic forces holding the fabric of your body's tissues together overpowers the force of friction between you and the trampoline. The next person on the trampoline would be getting pulled away from you, though.

Answer 2

The solar system isn't expanding.  The gravity that holds all its pieces in their place easily overcomes the expansion of spacetime which is only relevant on vastly larger distances.  Even Andromeda and the Milky Way galaxies' mutual gravitational attraction overcomes the expansion of the space between them.