I don't understand why a comet would circle (ellispse, whatever) a flat, ethereal spotlight sun? By your own reasoning (especially you Tom, pay attention here) the universal Accelerator affects denser objects more, so unless those little balls of ice are astronomically dense (thereby about equal to the sun, so there'd be no reason to circle it) the Earth would fly into the comets. I know some fall into the atmosphere, but this would happen to ALL comets.
This isn't stupid made up laws of science here, this is pure logic