Obviously 5 stars. I mean, based on the level of research alone, it deserves full stars. I can't even imagine... although, I should say that I'm a total layman when it comes to space travel, so all this "research" could be complete speculation on the author's part. But then he would get full stars for making it sound plausible. 6 of one, half dozen of the other. 
 If you're put off by technical jargon, then this might not be the book for you. It's chock full of scientific goodness! Without it, the book would have been lame. And half the length. But besides, it's also full of danger, excitement, and a surprising amount of sarcastic humor. 
 I stopped seeing the characters as fictional creations. I completely immersed myself in this book, and gave the characters all real faces and voices. And now that I've read the book, I can safely view the movie without spoilers. I will, however, criticize every change Hollywood made in the transition to screen.