Originally reviewed at Hooked on Books Christa's Hooked on Books 
 I read this book a week ago and I am still creeped out by it! 
 Set in a distant but familiar future, 172 Hours on the Moon, opens with NASA deciding to reopen missions to the moon. This felt very timely with last year's final space shuttle launch. I know there are more than a few people who were disappointed by this decision. In addition to the reopening of the space program, it is also revealed that during the original moon landng in 1969, the U.S. government built a secret base called DARLAH 2 on the surface of the moon. And if that weren't enough of a twist they're going to be sending three teenagers up to stay at the base for a week (with a crew of highly trained astronauts of course). 
 I was immediately sucked in by this unique and interesting plot. It was incredibly well researched and the science blended in seamlessly with the story. The amount of detail I know about space/moon could probably fill a tiny journal page but Johan Harstad gives you all the background and information you need in an easy to understand format, but without seeming like he's dumbing it down for the readers. I felt incredibly well informed by the end of the novel and even a little curious to do further research on my own. 
 I also really loved the wide cast of characters. All three teens are developed equally and it isn't until the last quarter of the book that you find out whether this is an ensemble story or one with a clear main character. I thought this was a neat method and it added an extra layer of mystery to the story as a whole. 
 But best of all is just how creepy this book is. It's haunting and at times quite disturbing. I loved getting caught up in the mystery and getting spooked by the different plot twists. I was on tenterhooks right until the very last page. And all of this takes place on the moon! Which just provided an awesome and unknown setting for the story to play out on. 
 Final recommendation: Highly recommended for science fiction fans as well as those who love a good mystery/horror story.