A lot of cliches
The lens flare and the 'render clouds', from what I can tell at a glance.
I'm gonna go on a limb here and assume you're still familiarizing yourself with the program.
Well, you've fallen in a few typical pitfalls; the 'techniques' are obvious and therefore detrimental to the final piece.
Further going down the line, the lens flare is blinding and really takes away the attention from the planet, which I assume is the centerpoint.
When you start off thinking about what you do, don't lose sight of that during the making of it. Often you'll find yourself going 'It would be cool, if I added... ', which it often isn't. I slap myself around the entire time for doing that.
That's all I have to say at this hour.
Cheers.