You've got a type of art I've never seen before, with all these space shots. They are absolutely gorgeous! I like this one in particular. It's full of action, and who doesn't like glowing things? xD Great job!
they all said it before, it's that big planet that spoils it a bit, it's not that detailed (well, if you want to go for a more flat surface that's perfectly understandable offcourse ) but the darkness on the botom looks of, gives the planet a weird shape, makes it feel as if it's not a planet at all ...
the more red lens flare in the upper right feel a bit off too, but overall it's a great piece.
I just...don't like it. There's something about the primary planet that just looks off to me; I think it's the texture. The central moon is not recieving enough light from the flare, and it should also be recieving light from the star behind it. I also think the secondary moon needs more lighting as well.
Other than that, I just think the starfield needs some work.