or sponsored by one of these private companies. at nasa, we discovered a little—known department where these risk—taking adventurers live. right now, there are four astronauts inside a spacecraft on a mission to phobos, one of mars�*s two moons. whispers: but they're actually in there. yes, in this tiny habitat, volunteers are locked away for 45 days on a simulated mission, with cameras and scientists monitoring their every move. this is nasa's human exploration research analog — hera for short.