                        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.

                                2024 July 31
   Part of a large rock on Mars is shown being mostly orange. On the rock
   are several irregular light-colored areas surrounded by a dark border.
   The spots are only millimeters across but might carry big implications.
          Please see the explanation for more detailed information.

                       Leopard Spots on Martian Rocks
          Image Credit: NASA, JPL-Caltech, MSSS, Perseverance Rover

   Explanation: What is creating these unusual spots? Light-colored spots
   on Martian rocks, each surrounded by a dark border, were discovered
   earlier this month by NASA's Perseverance Rover currently exploring
   Mars. Dubbed leopard spots because of their seemingly similarity to
   markings on famous Earth-bound predators, these curious patterns are
   being studied with the possibility they were created by ancient Martian
   life. The pictured spots measure only millimeters across and were
   discovered on a larger rock named Cheyava Falls. The exciting but
   unproven speculation is that long ago, microbes generated energy with
   chemical reactions that turned rock from red to white while leaving a
   dark ring, like some similarly appearing spots on Earth rocks. Although
   other non-biological explanations may ultimately prevail, speculation
   focusing on this potential biological origin is causing much intrigue.

         New Mirror: APOD is now available from Brazil in Portuguese
                       Tomorrow's picture: open space
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       Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)
            NASA Official: Amber Straughn Specific rights apply.
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                      A service of: ASD at NASA / GSFC,
                           NASA Science Activation
                             & Michigan Tech. U.

