|Picture Scramble # 56
||30 November 2000
The "Spirograph" Nebula
Glowing like a multi-faceted jewel, the planetary nebula
IC 418 lies about 2,000 light-years from Earth in the
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A planetary nebula represents the final stage in the
evolution of a star similar to our Sun. The star at the
center of IC 418 was a red giant a few thousand years
ago, but then ejected its outer layers into space to
form the nebula, which has now expanded to a diameter
of about 0.1 light-year. The stellar remnant at the
center is the hot core of the red giant, from which
ultraviolet radiation floods out into the surrounding gas,
causing it to fluoresce. Over the next several thousand
years, the nebula will gradually disperse into space,
and then the star will cool and fade away for billions
of years as a white dwarf. Our own Sun is expected to
undergo a similar fate, but fortunately this will not
occur until some 5 billion years from now.
(Courtesy of NASA and The Hubble Heritage Team, STScI/AURA)
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