Its alright
But you're trying too hard. Flash is only capable of so much, and a detailed RTS falls beyond its limits.
Its a nice concept, but asides from the obvious flash related issues (like pathfinding and enemy AI) there are one or two things I have a problem with. Its probably just me being a nerd, but its going to need a lot more than a near miss of an asteroid to knock our planet out of orbit. It has collided with planets the size of mars before, and our orbit was never in jeapody.
Also planets seem to have too little room to build on. Its part of the making a space based RTS on a 2D interface, when space requires 3D more than any other area.
Try something simpler next time because this sort of idea deserves better than flash.