Noy Jitat !

Simply amazing. Must use this in my next novel. Oh, wait. My next novel is about a bunch of English schoolchildren in trouble. Well, I ‘ll throw in a flight-to-Mars scene or something.

The winch unreeled 20 km of insulated, conducting tether with a spherical satellite at the end. As the Shuttle orbited the Earth, the electrical wire cut through the Earth’s magnetic field , and the motion produced an electrical current. Electrons – which make up a current – were collected by the satellite, through the tether, and flowed out the Shuttle by way of an electron gun that dumped the charge as it built up.

What Stone and other scientists found was that the tethered system produced more current that expected.

“The theoretical models were not accurate on tether,” Stone said, “and the currents were higher than we expected.” Specifically, the models require that the voltage be 10 times greater to collect a current than what was observed. Before the flight, the models predicted that the tether would produce 0.5 amp (0.5 A) under ideal conditions. Instead, it produced more than 1 amp under less than ideal conditions.

“The models were a factor of two or three off because they don’t include the effects of orbital motion through the plasma (electrified gas) of the ionosphere,” Stone said. While motion of a conductor through the magnetic field is crucial (it’s also how a generator in a power plant works), motion through the electrons in space was thought to be a miniscule effect. The Shuttle moves at 7.7 km/s (17,500 mph) while the electrons move at 200 km/s (115,000 mph).

It turns out that the current carried by those electrons connected nicely with the tethered system and “contributed significantly” to the power generated.