Gallery: Astronauts Explore Undersea 'Asteroid'

Neemo 15 Crewmembers

NEEMO 15 crewmembers, (from left to right) Takuya Onishi of the Japanese Aerospace Exploration Agency, David Saint-Jacques of the Canadian Space Agency, Steve Squyres of Cornell University, and Shannon Walker of NASA, prepare to splash down and start their mission on Oct. 20, 2011.

NASA NEEMO 15 Mission - Simulating an Asteroid

NASA's NEEMO 15 expedition will simulate aspects of a mission to an asteroid. In this illustration, a configured rock wall can be seen near the underwater Aquarius laboratory.

Neemo 15 Cewmembers Training

NEEMO 15 crewmembers David Saint-Jaques and Steve Squyres receive training on Oct. 15, 2011 to familiarize themselves with the tools they will be using on their mission.

Neemo 15 Cewmembers Morning Meeting

A portion of the NEEMO 15 Mission Control team receives instructions during a morning meeting on Oct. 17, 2011.

NEEMO 15 Training on Asteroid Simulation Wall

During a training session for the NEEMO 15 mission, planetary scientist Steve Squyres (left) and Japanese astronaut Takuya Onishi (right) get familiarized with the underwater asteroid simulation wall.

NEEMO 15 Crewmembers Splash Down

NEEMO 15 crewmembers prepare to dive to the Aquarius Underwater Laboratory on Oct. 20, 2011.

Artist Illustration - Mission to an Asteroid

Artist's concept of anchoring to the surface of an asteroid.

Neemo 15 Aquanauts Underwater

NASA astronaut Shannon Walker, Japanese astronaut Takuya Onishi (JAXA), planetary scientist Steve Squyres, and Canadian astronaut David Saint-Jacques, pose outside the Aquarius Underwater Laboratory on Oct. 21, 2011. Habitat technicians and professional "aquanauts" Nate Bender and James Talek can be seen inside.

Traversing the Asteroid Surface

n one of the mission's extravehicular activities, Canadian astronaut David Saint-Jacques experiments with tethering to a solid surface.

Steve Squyers Anchors to Asteroid Wall During NEEMO 15 Mission

Steve Squyers maneuvers to an anchor point on "asteroid" rock wall during one of the extravehicular activities.

Crewmembers Use Translation Lines to Collect Samples

Steve Squyers (Cornell) and David Saint-Jacques (CSA) use translation lines to collect interesting samples on the surface. As part of the NEEMO 15 mission, the aquanauts are experimenting with different ways to move around and perform science on the surface of an asteroid.