Posts Tagged ‘messages’
There are no signs to announce the edge of the solar system, but when the venerable Voyager 2 spacecraft approached this final frontier last Aug. 31 it was in for quite a shock. So were the scientists who analyzed the data that the craft radioed back to Earth, along with related observations by NASA’s twin Earth-orbiting STEREO spacecraft.
The signals reveal that at a distance of 83.7 astronomical units (1 AU is the average Earth-sun separation), Voyager 2 had at least five encounters with a turbulent region known as the termination shock. That’s the place where the solar wind — the sun’s hot supersonic wind of protons and other charged particles, which carves the heliosphere, a bubble in space extending well beyond the orbit of Pluto — slams into cold interstellar space and abruptly slows…
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