It's a haunting sight: a lonely astronaut clad in a spacesuit, standing in a gray, otherworldly landscape.

But why are bubbles coming out of the spacesuit? It turns out this "spaceman" actually worked at the bottom of the Mediterranean Sea during underwater training sessions conducted by the European Space Agency (ESA) when these underwater moonwalk photos were taken on Sept. 4.

ESA astronaut Jean-François Clervoy, seen in the photo, and ESA astronaut instructor Hervé Stevenin adopted the roles of Neil Armstrong and Buzz Aldrin for an underwater simulation of the historic Apollo 11 mission to the moon, entitled "Apollo 11 Under The Sea." The French deep-diving company Comex simulated the gravity on the moon by adjusting the astronaut’s buoyancy to one-sixth of the gravity felt on Earth. Observers watched from mission control on the Comex research vessel, Minibex, floating above.

Clervoy and Stevenin wore a Comex-designed Gandolfi spacewalk training suit, based on the Russian Orlan spacesuit. During the mission, the aquanauts collected several soil samples with tools similar to those used on the moon by the Apollo 11 crew. Clervoy is an experienced astronaut, having flown three space missions aboard NASA's now-retired space shuttle. Stevenin, spacewalk training lead at the European Astronaut Centre in Germany, is an experienced instructor for ESA astronauts.

This underwater test represented a first step toward developing European expertise in spacewalk simulations under partial gravity for exploring the moon, asteroids and Mars, ESA officials said.

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