This is a soothing piece with a surreal feel to it (Obviously the goal was achieved). The pinkish glow of the nebulae gives off creates a calm and lazy air around the planet and moons which are placed in a way that creates a horizontal line across the plane of the piece.
These factors combined are what create the actual surreality that is this piece, the fact that the planets, moons, and stars (all things that we know simply float within the zero gravity vacuum of space) seem to be suspended in the nothingness to such a degree that there would be no movement what so ever, just the glow of a few close stars and the nebulae. Bodies simply frozen in time, which for a known fact is impossible because there is always movement in space; hence the surreality. This image is so still that it's mind blowing. I look at it and wish that I could take in a sight like this in person.
Asides from that, what makes this scape so successful is the depth that is created, allowing the eye to wander from the larger bodies to the connect-the-dots of a variety of stars that are what form the very effect of depth itself, with the larger brighter stars creating a close plane, and smaller, dimmer stars receding slowly back into space, creating the endless background.
The style is beautiful and very well executed, and I think that this is a wonderful, awe inspiring piece.