I wanted to like it. I really really did. But there was just too much detailed science for me. Science was never my strong suit and so much of the book went right over my head. Reading Mark's logs felt like reading a manual: "How to Survive on Mars". 
 I also felt that the book lacked momentum. There was a very set pattern to the storytelling. Mark's logs described the science that was happening on Mars. He'd make light of his predicament with some emojis and pithy sarcastic comments. Then back on Earth everyone is freaking out about this or that problem. And then a brilliant scientist steps forward with a genius solution to said problem. Back to Mark. More emojis, science, and sarcasm. Back to Earth. Problem! Oh no, wait, it's solved! Back to Mark. I never felt in suspense. I was never worried that Mark wouldn't make it back home. 
 I'm a reader who loves strong character development and this book just didn't have it. I was expecting more of a survivalist story a la Castaway. Or Gravity. But it never felt like Mark underwent any kind of internal transformation. He came off as very one-dimensional. 
 The book is cool because of the accurate science and the ingenuity required to survive and rescue an astronaut on Mars. I admire the author's work and knowledge of his subject. But I just wasn't gripped by the story because of the lack characterization and suspenseful storytelling.