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Birthday · September 20, 2002

The Crab Nebula Pulsar Shrugs

September 20, 2002

Your birthday marks the moment a small planet circling a modest star gained another witness to its wonders.

The Crab Nebula Pulsar Shrugs

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APOD published September 20, 2002. Full image credits are on the original APOD entry below. A publication-date match, not a photo taken on your date. Independent of NASA.

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The Crab Nebula Pulsar Shrugs

Original APOD · September 20, 2002

How does a city-sized neutron star power the vast Crab Nebula? The expulsion of wisps of hot gas at high speeds appears to be at least part of the answer. Yesterday time-lapse movies taken from both the Chandra X-ray Observatory and the Hubble Space Telescope were released showing a wisp of gas moving out at about half the speed of light. Wisps like this likely result from tremendous electric voltages created by the central pulsar, a rapidly rotating, magnetized, central neutron star. The hot plasma strikes existing gas, causing it glow in colors across the electromagnetic spectrum. Pictured above is a composite image of the center of the Crab Nebula where red represents radio emission, green represents visible emission, and blue represents X-ray emission. The dot at the very center is the hot pulsar spinning 30 times per second.

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