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.

July 21, 1997
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In the Center of the Keyhole Nebula
Credit and Copyright: D. Malin (AAO), AATB, UKS Telescope

Explanation: Stars, like people, do not always go gentle into that good night. The above Keyhole Nebula results from dying star Eta Carinae's violently casting off dust and gas during its final centuries. Eta Carinae is many times more massive than our own Sun, and should eventually undergo a tremendous supernova explosion. Eta Carinae emits much light in colors outside the human visible range. This past week, X-ray emission from Eta Carinae was verified by the orbiting Rossi X-Ray Timing Explorer to be periodic, peaking every 85.1 days. This, along with a previously hypothesized 5.52 year period, indicates that the dying star might be part of a multiple star system.

Tomorrow's picture: A Presidential Panorama of Mars

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Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (USRA)
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