                        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.

                               2021 August 19

                          Bright Meteor, Starry Sky
       Image Credit & Copyright: Miguel Claro (TWAN, Dark Sky Alqueva)

   Explanation: Plowing through Earth's atmosphere at 60 kilometers per
   second, this bright perseid meteor streaks along a starry Milky Way.
   Captured in dark Portugal skies on August 12, it moves right to left
   through the frame. Its colorful trail starts near Deneb (alpha Cygni)
   and ends near Altair (alpha Aquilae), stars of the northern summer
   triangle. In fact this perseid meteor very briefly outshines both, two
   of the brightest stars in planet Earth's night. The trail's initial
   greenish glow is typical of the bright perseid shower meteors. The
   grains of cosmic sand, swept up dust from periodic comet Swift-Tuttle,
   are moving fast enough to excite the characteristic green emission of
   atomic oxygen at altitudes of 100 kilometers or so before vaporizing in
   an incandescent flash.

         Notable APOD Image Submissions: Perseid Meteor Shower 2021
                    Tomorrow's picture: Three Dark Nights
     __________________________________________________________________

       Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)
            NASA Official: Phillip Newman Specific rights apply.
                NASA Web Privacy Policy and Important Notices
                      A service of: ASD at NASA / GSFC
                             & Michigan Tech. U.


