Open Course Info


Introduction to Astronomy


Betelgeuse HST Photo


This photo of Betelgeuse, taken on 1995 March 3 by the Hubble Space Telescope, revealed its actual size, the first time ever for a star besides our Sun. Betelgeuse is a red supergiant that marks the upper left shoulder of the constellation of Orion. It's a good candidate for such an observation due to its huge size, encompassing a region larger than Jupiter's orbit (which is 10.4 A.U. in diameter).

This image was taken in the ultraviolet, so it is presented in false color. It reveals the surface of the star (red) and a mysterious, gigantic hot spot on the surface (white), estimated to be at least 2000 K hotter than the rest of the surface.

The observation of Betelgeuse was performed by Andrea Dupree (Harvard-Smithsonian Center for Astrophysics) and Ronald Gilliland (Space Telescope Science Institute). The Hubble Space Telescope is operated by the Space Telescope Science Institute under a cooperative agreement with the National Aeronautics and Space Administration.



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.
©1996-2001 Scott R. Anderson
Last update: 2002 February 2
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