Photos: NASA prepares for moon mission--under water

Three astronauts and a Constellation Program aerospace engineer are spending 10 days at the bottom of the ocean--simulating what life could be like at a moon base or in outer space. The aquanauts are staying at the National Oceanic and Atmospheric Administration (NOAA) Aquarius Underwater Laboratory though Wednesday.

The crew members of the the NASA Extreme Environment Mission Operations 13 (NEEMO 13) are practicing moonwalks for future lunar exploration--using advanced navigation and communications equipment.