I don't think I've read a sci-fi book since I, Robot back in Middle School, but DAMN The Martian was the perfect "Welcome Back to the Genre" book. It's exciting, it seems like just enough fact-checking happened to make this story plausible, and it appeals to every kid who's ever wanted to be an astronaut just so they could mess around with a bunch of cool space gadgets.The story is about Mark Watney, who gets left behind by his team during a Mars exploration mission. The next mission to mars is 4 years away, and Mark Watney needs to find a way to survive that long on 52-days worth of meals. That's far from the only problem he has to deal with though.
Other than the constant excitement and tension created by the avalanche of problems heading for Mark, the book is exciting because of Mark's character. He's witty, sarcastic, and just on the right side of "too much ego". It's clear from the book that this isn't just an outcome of being in a stressful situation, and knowing that Mark is always like this makes it even easier to empathize with.
When it comes to scientific accuracy this book holds up too. We don't have all the technology necessary for interplanetary travel right now (hurry up, SpaceX), but it's so close to feeling real that it seems this story could happen IRL in decade or so.
The best part of the book, in my opinion, is that it doesn't explicitly push the moral of the story. Until the last paragraph of the book, the story is just that — a story. The characters' actions speak for themselves.
I strongly recommend that you read the book before the movie comes out. It's short and thrilling enough to be read in a week, and knowing the plot beforehand will set you up for paying attention to Ridley Scott's directing, which is going to be unjustly criticized by everyone and their grandma. Mark my words.