                        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 November 21

                     3I/ATLAS: A View from Planet Earth
                 Image Credit & Copyright: Rolando Ligustri

   Explanation: Now outbound after its perihelion or closest approach to
   the Sun on October 29, Comet 3I/ATLAS is only the third known
   interstellar object to pass through our fair Solar System. Its greenish
   coma and faint tails are seen against a background of stars in the
   constellation Virgo in this view from planet Earth, recorded with a
   small telescope on November 14. But this interstellar interloper is the
   subject of an on-going, unprecedented Solar System-wide observing
   campaign involving spacecraft and space telescopes from Earth orbit to
   the surface of Mars and beyond. And while the comet from another
   star-system has recently grown brighter, you'll still need a telescope
   if you want to see 3I/ATLAS from planet Earth. It's now above the
   horizon in November morning skies and will make its closest approach to
   Earth, a comfortable 270 million kilometers distant, around December
   19.

               Tomorrow's picture: Dione and Rhea Ring Transit
     __________________________________________________________________

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