The moment is almost here. NASA is about to launch its next-generation rocket for the first time and send it hurtling out beyond the Moon. It’s going to be a wild time, but honestly, there’s been a lot going on here on Earth, too — and if you’re anything like me, you might be in the market for a quick refresher on what exactly is going down when NASA’s next big thing blasts off. 

Consider this your SLS cheat sheet as NASA gears up for its big launch on November 16th.