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Monday, May 18, 2015

Science: the flux we live in

image: illustration using SGR 1745-525
Magnetar SGR 1745-525, NASA-Chandra

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On May 16th NASA issued a press release reporting that a magnetar near a supermassive black hole delivers surprises. The black hole is the one at the center of the Milky Way; the surprise is that
the amount of X-rays from SGR 1745-2900 is dropping more slowly than other previously observed magnetars, and its surface is hotter than expected.
My interest was piqued. On researching the literature about Magnetars, I found this
1979 discovery
On March 5, 1979, a few months after the successful dropping of satellites into the atmosphere of Venus, the two Soviet spacecraft that were then drifting through the Solar System were hit by a blast of gamma radiation at approximately 10:51 EST. This contact raised the radiation readings on both the probes from a normal 100 counts per second to over 200,000 counts a second, in only a fraction of a millisecond.
This burst of gamma rays quickly continued to spread. Eleven seconds later, Helios 2, a NASA probe, which was in orbit around the Sun, was saturated by the blast of radiation. It soon hit Venus, and the Pioneer Venus Orbiter's detectors were overcome by the wave. Seconds later, Earth received the wave of radiation, where the powerful output of gamma rays inundated the detectors of three U.S. Department of Defense Vela satellites, the Soviet Prognoz 7 satellite, and the Einstein Observatory. Just before the wave exited the Solar System, the blast also hit the International Sun-Earth Explorer. This extremely powerful blast of gamma radiation constituted the strongest wave of extra-solar gamma rays ever detected; it was over 100 times more intense than any known previous extra-solar burst. Because gamma rays travel at the speed of light and the time of the pulse was recorded by several distant spacecraft as well as on Earth, the source of the gamma radiation could be calculated to an accuracy of about 2 arcseconds. The direction of the source corresponded with the remnants of a star that had gone supernova around 3000 B.C.E. It was in the Large Magellanic Cloud and the source was named SGR 0525-66, the event itself was named GRB 790305b, the first observed SGR megaflare.
From another section of the Wikipedia article we learn that "magnetars are around 20 kilometres (12 mi) in diameter and have a greater mass than the Sun." Despite this minute size in comparison to other celestial bodies, the burst of radiation raised the radiation reading from the normal 100 count per second to over 200,000 counts per second in a timeframe of milliseconds when detected by the Soviet probes. None of the radiation is reported to have been detected within Earth's atmosphere.

This is a tale of only one magnetar event. "As of November 2013, 21 magnetars are known, with five more candidates awaiting confirmation." reports Wikipedia.

What I wonder is how is life on Earth would be affected if such radiation penetrated Earth's atmosphere. The wave passed through the solar system at the speed of light, too fast for our bodies to detect and react. But the brain works with electricity, which is in the same realm as solar and other radiation. This EPA page gives a good summary of types of radiation.

If magnetar and similar radiation events affect our brains, how? Mentally? Emotionally? An image that comes to mind is the event following contact with the monolith in 2001: A Space Odyssey: an ape's discovery of using a tool. Don't get me wrong, I'm not saying we should walk around wearing tin-foil helmets, but I am asking if historical and social events are sometimes triggered by the celestial flux we live in.
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image: screenshot from 2001: A Space Odyssey
Discovery, 2001: A Space Odyssey
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-- Marge


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