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File:Sirius A & B X-ray.jpg

Sirius_A_&_B_X-ray.jpg(420 × 331 pixels, file size: 248 KB, MIME type: image/jpeg)


English: An X-ray image of the Sirius star system located 8.6 light years from Earth. This image shows two sources and a spike-like pattern due to the support structure for the transmission grating. The bright source is Sirius B, a white dwarf star that has a surface temperature of about 25,000 degrees Celsius which produces very low energy X-rays. The dim source at the position of Sirius A – a normal star more than twice as massive as the Sun – may be due to ultraviolet radiation from Sirius A leaking through the filter on the detector. In contrast, Sirius A is the brightest star in the northern sky when viewed with an optical telescope, while Sirius B is 10,000 times dimmer. Because the two stars are so close together Sirius B escaped detection until 1862 when Alvan Clark discovered it while testing one of the best optical telescopes in the world at that time.
Date 26 September 2000
Source CHANDRA X-ray Observatory CXC Operated for NASA by SAO, url=
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Image is 77 x 62 arcsec across. RA 06h 45m 11s Dec -16° 42' 05.00" in Canis Major. Observation date: October 28, 1999. Instrument:ACIS.


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