Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

October 31, 1999
See Explanation.  Clicking on the picture will download 
 the highest resolution version available.

The Cat's Eye Nebula
Credit: J.P. Harrington and K.J. Borkowski (U. Maryland), HST, NASA

Explanation: Three thousand light-years away, a dying star throws off shells of glowing gas. This image from the Hubble Space Telescope reveals The Cat's Eye Nebula to be one of the most complex planetary nebulae known. In fact, the features seen in the Cat's Eye are so complex that astronomers suspect the bright central object may actually be a binary star system. The term planetary nebula, used to describe this general class of objects, is misleading. Although these objects may appear round and planet-like in small telescopes, high resolution images reveal them to be stars surrounded by cocoons of gas blown off in the late stages of stellar evolution. On planet Earth, of course, cats and other creatures may be on the prowl tonight. Keep your eyes peeled and have a safe and happy Halloween!

Tomorrow's picture: The Rotten Egg Planetary Nebula


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Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (USRA)
NASA Technical Rep.: Jay Norris. Specific rights apply.
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