Imagine being alone in the vastness of space and seeing an unidentified object approaching rapidly. There are so many unknowns out there. It could be a piece of debris, but what if it's something else? The feeling of helplessness would be overwhelming.
One of the best astronaut novels is 'The Martian' by Andy Weir. It's about an astronaut stranded on Mars and his struggle for survival. It's full of scientific details and the protagonist's unwavering will to live makes it a great read.