If I may offer an unsolicited opinion...
I know that the design of your book is not final but the cover seems to dark and cold--and the Milky Way doesn't have the feel of the proper background. I always liked the cover of Jerry Patterson's BLACKJACK A WINNER'S HANDBOOK. MILLION DOLLAR BLACKJACK isn't bad either. But then why be so pedestrian when you can display the ethereal beauty of the cosmos. What's the tempature out there, 1% above absolute zero? Burrrrr.