Open Course Info


Introduction to Astronomy


Runaway Star Photo


The bright star HD 77581, over 6000 light years away, has an unseen binary companion, the x-ray source Vela X-1, believed to be a neutron star produced by a supernova explosion. The "kick" of this explosion is believed to have sent the pair speeding away through the interstellar medium.

This photo of HD 77581 was released 14 January 1997 by the European Southern Observatory. It was taken by L. Kaper et. al. with the 1.54-m Danish telescope at the ESO La Silla Observatory. Used with permission.


The star chart background was produced on a Macintosh with the Voyager II program, and are ©1988-93 Carina Software, 830 Williams St., San Leandro, CA 94577, (510) 352-7328. Used under license.
©1996-2000 Scott R. Anderson
Last update: 2000 March 26
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