I've seen pieces like this in the past but none with such a wonderful attention to color. The thing that I love about space scenes is there's a complete disregard for verisimilitude; the planets can be as close to one another as they please, defying gravity, and the things which happen to them can be equally impossible and beautiful all at once. Congratulations! A stunning visual experience.
To be honest, the planet texture looks crappy to me. It isn't very diverse or pleasing to the eye. The explosion on the other hand, is an awesome piece of work that obviously had a lot of time put into it. The amount of detail is amazing! And the size of your image!