The Neutral Buoyancy Laboratory (NBL) is an astronaut training facility maintained by and located at the Sonny Carter Training Facility on NASA’s Johnson Space Center in Houston, Texas. The NBL consists of a large indoor pool of water, the largest in the world, in which astronauts may perform simulated EVA tasks in preparation for upcoming missions.
The NBL contains full-sized mock-ups of the Space Shuttle cargo bay, flight payloads, and the International Space Station (ISS).
The NBL tank itself is 202 feet (62 m) in length, 102 feet (31 m) wide, and 40 feet 6 inches (12.34 m) deep, and contains 6.2 million gallons (23.5 million litres) of water.
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