|MadSci Network: Physics|
Bill, There have been tests to harness this electric potential for use in space. Just like an electric generator develops electricity by passing wires through a magnetic field, a metal wire passing through the earths magnetic field in space will also produce electricity. The type of electricity generated would be direct current. In the early 1996, the Space Shuttle Columbia (Mission STS-75) carried aloft a 1/2 ton satellite that would stay connected to the Space Shuttle with a 12.8 mile long tether to test this method of generating electricity. This mission failed when about six hours into the deployment, the tether broke. Four years early they had attempted this same test, but only got the satellite reeled out 840 feet when the tether snagged on a bolt. More information about the STS-75 tether experiement can be found at nasa.gov/earthmag/wtether Despite the failure of the experiment, the electicity generated by the tether as it was extending matched predictions. This means the experiment proved the computer models, and show that tethers could be used for electricity generation in the future. Hope this helps. Todd Engelman Aerospace Engineer
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