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| | Alula Australis |
 | | While Mizar was the first known "double star," our Alula was the first double to be identified as physically related (by no other than William Herschel, the discoverer of Uranus in 1781), when he saw that the two orbited each other. |
 | | Alula Aust B is (like the Sun) also magnetically active, with a hot corona with a temperature measured to be between 2 and 6 million Kelvin. |
 | | To reconcile the sum of all masses, Alula Aust A's companion must carry a mass of 0.5 solar masses, rendering it a cool class M dwarf as well. |
| www.astro.uiuc.edu /~kaler/sow/alulaaus.html (648 words) |
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