                        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.

                               2023 January 14

                             Perihelion Sun 2023
       Image Credit & Copyright: Peter Ward (Barden Ridge Observatory)

   Explanation: Perihelion for 2023, Earth's closest approach to the Sun,
   was on January 4 at 16:17 UTC. That was less than 24 hours after this
   sharp image of the Sun's disk was recorded with telescope and H-alpha
   filter from Sidney, Australia, planet Earth. An H-alpha filter
   transmits a characteristic red light from hydrogen atoms. In views of
   the Sun it emphasizes the Sun's chromosphere, a region just above the
   solar photosphere or normally visible solar surface. In this H-alpha
   image of the increasingly active Sun planet-sized sunspot regions are
   dominated by bright splotches called plages. Dark filaments of plasma
   snaking across the solar disk transition to bright prominences when
   seen above the solar limb.

                    Tomorrow's picture: cosmic crustacean
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       Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)
            NASA Official: Phillip Newman Specific rights apply.
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