Extreme Environment Mission Operations program (NEEMO)

For astronauts floating hundreds of miles above the Earth in an airless, weightless atmosphere, even the simplest tasks need to be thought out in detail, planning for every step. Thousands of man hours and millions of dollars go into space exploration, and once the rocket has reached the silent depths of space, things absolutely must go as planned. There's no room for error.

The only frontier left on Earth, it is said, is the oceans, and for astronauts of NASA and the European Space Agency, these deep terrestrial environments provide the conditions needed to simulate space missions. It's the perfect place to test the techniques and instrument performance for the future of space exploration, and now NASA is looking at asteroids as their next great space destination.

The NASA Extreme Environment Mission Operations program (NEEMO) project 16 allowed astronauts the chance to train for a manned mission to an asteroid, something NASA has outlined as a core goal, hoping to land a man on a speeding space rock by 2025.