[quote=@Lauder]
[@Forsythe]

Well I am having their home planet being in the center of an asteroid cluster/field so it's a precaution by the humans I would suppose
[/quote]

The thing is, that would be a very rare if not impossible occurrence. The gravity of the planet would eventually "win" and pull the asteroids towards itself, either adding them to its own mass or making a moon/asteroid ring of them. It would make it more believable if the planet was merely intersecting the asteroid belt at 2 times a year - it is still very dangerous, enough to warrant such a precaution, but more acceptable for the local nerds =D

I had something like this originally on my artifact list, I called it "fortress world" - it used a giant, planetary wide shield instead of a defense gun. The prop of that is that since the shield emitter itself would be inside, it couldn't get destroyed at all - a defense platform may still be overwhelmed. 

But to answer your question, yes, that is doable.