NASA's Neutral Buoyancy Lab
NASA's Neutral Buoyancy Laboratory located at the Johnson Space Center in Houston TX is the world's largest indoor pool. Astronauts use the pool to practice EVA's and installing various components on the International Space Station. This video is sped up 8x. The large white cylinder being transported in the video is s high fidelity mockup of the US Harmony node 2. It provides a passageway between three station science experiment facilities: the U.S. Destiny Laboratory, the Kibo Japanese Experiment Module, and the European Columbus Laboratory. The aluminum node is 7.2 meters (23.6 feet) long and 4.4 meters (14.5 feet) in diameter. Its pressurized volume is 70 cubic meters (2472 cubic feet, and its launch weight is approximately 30,000 pounds (13,600 kilograms). The real module is slated to launch on STS-120. The support SCUBA divers can be seen on the surface of the water. They breath Nitrox (air enriched with more oxygen) out of twin SCUBA tanks so that they can stay under water for up to 3 hours while they support the astronauts.