                        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.

                               2026 January 23

                          Planetary Nebula Abell 7
                    Image 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.

                        Tomorrow's picture: Earthset
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       Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)
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