                        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.

                                2025 June 27

                                 Messier 109
                    Image Credit & Copyright: Robert Eder

   Explanation: Big beautiful barred spiral galaxy Messier 109 is the
   109th entry in Charles Messier's famous catalog of bright Nebulae and
   Star Clusters. You can find it just below the Big Dipper's bowl in the
   northern constellation Ursa Major. In fact, bright dipper star Phecda,
   Gamma Ursa Majoris, produces the glare at the upper right corner of
   this telescopic frame. M109's prominent central bar gives the galaxy
   the appearance of the Greek letter "theta", θ, a common mathematical
   symbol representing an angle. M109 spans a very small angle in planet
   Earth's sky though, about 7 arcminutes or 0.12 degrees. But that small
   angle corresponds to an enormous 120,000 light-year diameter at the
   galaxy's estimated 60 million light-year distance. The brightest member
   of the now recognized Ursa Major galaxy cluster, M109 (aka NGC 3992) is
   joined by spiky foreground stars. Three small, fuzzy bluish galaxies
   also on the scene, identified (top to bottom) as UGC 6969, UGC 6940 and
   UGC 6923, are possibly satellite galaxies of the larger barred spiral
   galaxy Messier 109.

                      Tomorrow's picture: light-weekend
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       Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)
            NASA Official: Amber Straughn Specific rights apply.
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