I like the quite original idea. I'd really like to see more up. I think you should have painted the window entirely and add some dust on it, since this planet looks dusty. Colours are really nice, but I think the closer part of sand (or dust) of the observer should be highlighted, like it is between the two buildings. Indeed, the left buildings shadows are really too wide and should be stopped roughly at the horizontal middle of the image.

@Excorbac: Yes, you are certainly right about the shadows. I originally intended to have the area cramped with zombies hiding from the bright sunlight, while waiting for the juicy Earth-tourists to finish lunch and step outside for a stroll. Or something.
Later on I decided that I like the soritary calmness of the view, so I kept it like this. But yes, I should adjust the shadows accordingly, which would also add some more dynamicism to the composition as well.
I think showing the whole window isn't nessecary and might make the comp very stale/framey, but I definitely like your idea of some dust on it.
Thanks for the comment.

th0mas, just one thing, sorry I didn't intend to be that harsh on points, clicked too quicly (was in the hurry to go to work)! I wanted 8 points

@Excorbac: Hehe no worries mate. Constructive feedback is what matters. Thanks.

Looks good,
YEah I think this is better than teh zombie idea. Because with the zombie idea you are only nailing one look down. While this has a meaning for every viewer. It is really calming and still disturbing. I like it 7/7

great work

it looks good. it does indeed look deserted...i still feel that it looks like more of a concept sketch than a finished artwork that can stand on its own though