i could probably work on the clouds and maybe change the lips on the moon into a bluish color. this was just something thrown together cause i wasn't really feeling it.

a few bits of things to say, firstly the dithering on the cloud works quite well, but you go brighter onto the outside, which makes sense, but it could really use anti-alias, maybe using the colours on the lips of the moon, because it looks a little rigidy.

the texture on the moon looks awesome and works really well, but the lips dont fit it at all, it look like its been thrown on top rather than actually part of the picture, lastly the stars that dot the image, maybe they could use some AA as well, and maybe less stars, but more detailed few would work better, since at the moment they dont seem part of the background but instead just a sprinkle of white dots on the picture!