This is sort of a hybrid of Battlestar Galactica and any generic mecha, but with very lackluster graphics and a subpar story. The story's sin isn't just that it's the same as what's been done 1,000 times already, but that it's confusing as hell. I won't attempt to explain all this because, frankly, I'm not a very good writer and I'd confuse you even more than the show does.
I should disclose that I dropped it after 6 episodes. I wanted to stop watching after 2, but I almost always follow the 5 episode rule. I have no idea what made me watch the 6th. Anyway, maybe the sea of confusion parted after that, and maybe real animators came aboard the project, but unless this is the case, the show isn't worth your time.
If you want to watch a quality anime similar to this, try Knights of Sidonia. If you want something with mecha that has a pretty cool twist, watch Kuromukuro. (Don't be put off by the rank of 2,192 it's currently at - it's much better than that.)