Untitled Document
NASA and The Hubble Heritage
Team (STScI/AURA);
R. Sahai (Jet Propulsion Lab)
Planetary nebulae have nothing
to do with planets, but in crude or low-power telescopes they can look similar
to the fuzzy disks that planets present. Large modern observatories, like the
Hubble Space Telescope, can resolve these objects into dazzling detail.
The one, called NGC 3132,
is typical of the breed: An expanding cloud of gas surrounds a dying star. NGC
3132 is about a half of a light-year in diameter and is visible from the Southern
Hemisphere, where astronomers call it the Eight-Burst or the Southern Ring Nebula.
At just 2,000 light-years away, this nebula is one of the closest known.
Look at the center. You'll
see two stars. The fainter one is actually responsible for the beauty that surrounds
it. Having ejected its shell, it's now smaller than our Sun but very hot. The
intense ultraviolet radiation it emits lights up the nebula. The star that appears
brighter in this image is younger, and the two stars are gravitationally bound
in orbit around one another.
A third star is visible
in the upper right corner of the image, but it is not part of the system.
-- Robert
Roy Britt
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