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Mira AB
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Mira A (right), a highly evolved red giant star, and Mira B (left), a white dwarf, was imaged by the Chandra x-ray telescope, and shows Mira A losing gas rapidly from its upper atmosphere, via a stellar wind, and Mira B exerting a gravitational tug that creates a gaseous bridge between the two stars.
Gas from the wind and bridge accumulates in an accretion disk around Mira B and collisions between rapidly moving particles in the disk produce X-rays.
Mira A (or simply, Mira) was named "The Wonderful" star in the seventeenth century because its brightness was observed to wax and wane over a period of about 330 days. In this advanced red giant phase of Mira A's life, its diameter has swollen to about 600 times that of the Sun and it is pulsating, due to increasingly energetic nuclear reactions in its core.
Mira A is now approaching the stage where its nuclear fuel supply will be exhausted, and it will collapse to become a white dwarf. In contrast, Mira B has already reached the white dwarf stage, and is about the size of the Earth, but about a half million times more massive.
The stars in Mira AB are about twice as far apart as Pluto is from the Sun.
The star system is about 420 light years away in the constellation Cetus.
Position (J2000) RA 02h 19m 20.70s Dec -02 58' 39.51

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-- Edited by Blobrana at 19:51, 2005-04-28

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