Credit & Copyright: Martin Pugh
Explanation:
Very faint planetary nebula Abell 7 is about 1,800 light-years distant.
It lies just south of Orion in planet Earth's skies toward the
constellation
Lepus, The Hare.
Posing with scattered Milky Way stars, its
generally
simple spherical shape about 8 light-years in diameter is revealed in
this deep telescopic image.
The beautiful and complex shapes
seen within the cosmic cloud are visually
enhanced by the use of long exposures and
narrowband filters
that capture emission from hydrogen and oxygen atoms.
Otherwise Abell 7 would be much
too faint to be appreciated by eye.
A
planetary nebula
represents a very brief final phase
in stellar evolution that our own Sun will experience 5 billion
years hence,
as the nebula's central, once sun-like star shrugs off its outer layers.
Abell 7 itself is estimated to be 20,000 years old.
But its central star, seen here as a
fading white dwarf,
is some 10 billion years old.
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NASA Web Site Statements, Warnings, and Disclaimers
NASA Official: Jay Norris. Specific rights apply.
A service of: LHEA at NASA / GSFC
& Michigan Tech. U.
Based on Astronomy Picture
Of the Day
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Публикации с ключевыми словами:
planetary nebula - white dwarf
Публикации со словами: planetary nebula - white dwarf | |
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