The Return by Buzz Aldrin
Former astronaut Scott Blackstone's dream of opening outer space to visits from everyday people is under attack. His pilot programme has been marred by a fatal accident, he is out of a job, and he is being sued for a billion dollars. And it's beginning to seem that the "accident" wasn't at all accidental. Then the endless conflict between India and Pakistan heats up...and Pakistan explodes a nuclear device in the upper atmosphere, frying electronics on earth and in space, and putting the crew of the International Space Station at risk. With the Shuttle fleet grounded, only a secret skunkworks project known to scott and his old friends can save the space station's stranded crew.