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Mars Odyssey Completes Aerobraking
Cally writes: "Space.com reports that
Mars Odyssey has
completed aerobraking and is ready to begin its
main science mission. As the spacecraft has already produced exciting results before the start of the science mission proper, interesting data on the quantities of water in the Martian crust may be expected soon - not to mention that Odyssey provides another datapoint in the study of Gamma Ray bursts."
The experiment you refer to involved a tethered satellite. It was performed on February 25, 1996, and as miles of tether were unrolled, the dynamo current grew just as predicted. The tether was almost entirely unrolled when it broke near the shuttle's end, whipping off into the void. The shuttle crew tracked the satellite by radio for several minutes, then lost contact.
After the mission, the tether was examined on Earth, and was found to have been melted through. Turns out the core of the cable was a porous material that had atmospheric-pressure air trapped in it during manufacture. The air leaked out through pinholes in the outer insulation and was quickly converted, by the high voltage (~3500V) of the tether, to a plasma far denser and more conductive than the surrounding ionosphere. Instruments indicated that the plasma diverted a full ampere of current (at 3500 volts) through the insulator pinholes, enough to melt through the cable.
That's why they don't let astronauts EVA any more without gloves.
OffTopic: That last line was a feeble joke, similar to the one in my original post. That post was modded up three points (by those who took "regenerative aerobraking" seriously) before being modded down five (by those who take mismoderation seriously). Is there a record for the number of mod points, both up and down, assigned to a single comment?