I just finished Andy Weir's hard sci-fi story about an astronaut stranded alone on Mars after a freak accident and extenuating circumstances. It's very good and goes into a hellacious amount of detail in relating how a man could possibly survive such a situation. The research that must have gone into writing this book is staggering to think about, and seeing just how the main character MacGuyvers through each and every problem he's presented with is really interesting.
The problem with the book is mainly in the dialog between others back on Earth or the Hermes crew (on their way back to Earth after evacuating Mars and leaving behind our protagonist). It's terrible. It reads like awful sitcom-esque TV dreck. It's so bad it is distracting from the rest of the well-written parts of the book. It's not a huge part of the book, and far from the most important part of it, thankfully.
Overall, I did enjoy The Martian, and would certainly recommend it to anyone interested in the nitty gritty of spacefaring in the present and very near-term future. Almost nothing at all in here is beyond our current capabilities.