                        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 September 29
   A starfield is shown that has two short streaks running diagonally. At
   closer inspection, they are two comets both with white-green heads and
   white tails. Please see the explanation for more detailed information.

                        Two Camera Comets in One Sky
                 Image Credit & Copyright: Luc Perrot (TWAN)

   Explanation: It may look like these comets are racing, but they are
   not. Comets C/2025 K1 ATLAS (left) and C/2025 R2 SWAN (right) appeared
   near each other by chance last week in the featured image taken from
   France's Reunion Island in the southern Indian Ocean. Fainter Comet
   ATLAS is approaching our Sun and will reach its closest approach in
   early October when it is also expected to be its brightest -- although
   still only likely visible with long exposures on a camera. The brighter
   comet, nicknamed SWAN25B, is now headed away from our Sun, although its
   closest approach to Earth is expected in mid-October, when optimistic
   estimates have it becoming bright enough to see with the unaided eye.
   Each comet has a greenish coma of expelled gas and an ion tail pointing
   away from the Sun.

                       Growing Gallery: Comet SWAN25B
                  Tomorrow's picture: a third camera comet
     __________________________________________________________________

       Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)
            NASA Official: Amber Straughn Specific rights apply.
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                             & Michigan Tech. U.

