Have you dreamed of becoming a space explorer? You now have your chance to do something about it: after a four-year silence, NASA is once again hiring new astronauts. The recruiting drive will run between December 14th and mid-February, with the final selections made public in mid-2017. You'll need the right mix education, experience and stamina to even get your foot in the door (there's a long-term spaceflight physical, for example). However, it could easily be worth clearing that high bar.