A little wonder, every day

Astronaut training in water

NASA facility photograph showing divers and an astronaut in a spacesuit beside a station mockup in the Neutral Buoyancy Lab. NASA source: https://www.nasa.gov/wp-content/uploads/2023/06/nbl-tour-8c393102.jpg. NASA imagery; credited NASA on the facility page.

NASA/JSC image jsc2024e028394, JAXA astronaut Kimiya Yui during spacewalk training at the Neutral Buoyancy Laboratory, 25 April 2024. NASA/James Blair. Source: https://images-assets.nasa.gov/image/jsc2024e028394/jsc2024e028394~large.jpg.

NASA/JSC image jsc2023e080760, NASA astronaut Mike Fincke training for a spacewalk at NBL, 15 December 2023. NASA credit in NASA metadata. Source: https://images-assets.nasa.gov/image/jsc2023e080760/jsc2023e080760~large.jpg.

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NASA facility photograph showing divers and an astronaut in a spacesuit beside a station mockup in the Neutral Buoyancy Lab. NASA source: https://www.nasa.gov/wp-content/uploads/2023/06/nbl-tour-8c393102.jpg. NASA imagery; credited NASA on the facility page.

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Astronaut preparation includes both a swimming test and practice for future spacewalks. NASA describes a candidate requirement to swim three lengths of a pool without stopping and then three more in a flight suit and tennis shoes. To rehearse work around the International Space Station, astronauts train in a large NASA pool with full-scale mockups of parts of the station. Water and carefully adjusted weights create neutral buoyancy, which helps them practice movement in conditions resembling weightlessness, though it is not an exact copy of space.