                        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 June 8
   A starfield shows many red nebulas near the center. Running vertically
   up the left side are about 20 images of a comet, with the head towards
       the image bottom. Successively higher images of the comet show
       successively shorter tails. Please see the explanation for more
                            detailed information.

                       Comet R3 PanSTARRS Through Time
   Image Credit & Copyright: Jakub Kuřák & Martin Mašek (FZU of the Czech
                            Academy of Sciences)

   Explanation: What happens to a comet as it leaves our inner Solar
   System? Now, the arrival of a comet
   into the inner Solar System is typically heralded with great fanfare
   and high hopes that the comet will become bright and photogenic. But on
   the way out, the comet's nucleus is less warmed by the Sun, less gas
   and dust are expelled, the bright coma around the nucleus shrinks and
   fades, and the tail length drops off. Many comets will then return to
   the outer Solar System and only return in hundreds or thousands of
   years. In contrast, some comets -- like Comet C/2025 R3 (PanSTARRS) --
   receive a gravitational kick from the planets and so will never return.
   Pictured, Comet R3 PanSTARRs was imaged deeply many nights in early to
   mid-May near Cerro Paranal in Chile. Later images appear closer to the
   top and clearly show the shrinking ion tail.

                Comet R3 Gallery: Comet R3 PanSTARRS in 2026
                       Tomorrow's picture: heady Thor
     __________________________________________________________________

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

