It’s an age-old question: are we alone in the universe? Is there intelligent life out there? While some might scoff at the idea, even astrophysicist Neil deGrasse Tyson has mused that perhaps we are all just pets in an elaborate alien zoo. Whether you’re a believer or a skeptic, the thought of alien beings is a fascinating one that only breeds more questions. If they are real…what would happen if they came here? What would they be like? What would they do? What would we do? And how would we prepare?

Here are some out-of-this-world reads about our friendly and not-so-friendly neighbors in the cosmos. Read them, and prepare yourselves accordingly…you know…in case aliens are real.

Did I miss your favorite alien book? Let me know in the comments!