Astronaut Mike Gernhardt was deeply disappointed when he found out NASA's lunar missions would be discontinued. "Rather than go off and cry in the corner," however, he became the principal investigator at NEEMO (NASA's Extreme Environment Mission Operations), which explores survival underwater to prepare for space travel. This short documentary from Motherboard visits the Aquarius Reef Base, where aquanauts are studying what it will be like to work on asteroids. 

Why asteroids? They are full of rare materials that could be mined -- and one is slated to skim dangerously close to Earth on April 13, 2029. "The possibility that Earth will be hit by an asteroid in our lifetime isn’t huge," Alex Pasternack, the video's producer, writes at Motherboard, but "the threat is so potentially catastrophic ... [it's] one of those things that someone should probably be thinking about." Or as Neil deGrasse Tyson puts it, "we're clever enough that we never have to go extinct by an asteroid. We have more choices available to us than tyrannosaurus rex did." 

Read the full story at Motherboard here.