                        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 February 3

                     Polaris and the Trail of Comet ZTF
                Image Credit & Copyright: David Ibarra Gomez

   Explanation: Stars trace concentric arcs around the North Celestial
   Pole in this three hour long night sky composite, recorded with a
   digital camera fixed to a tripod on January 31, near Ąger, Lleida,
   Spain. On that date Comet C/2022 E3 (ZTF) was near its northernmost
   declination in planet Earth's sky. That put the comet about 10 degrees
   from Earth's North Celestial Pole making the comet's position
   circumpolar, always above the horizon, from all locations on planet
   Earth at more than 10 degrees northern latitude. In the startrail
   image, the extension of Earth's axis of rotation into space is at the
   left. North star Polaris traces the short, bright, concentric arc less
   than a degree from the North Celestial Pole. The trail of Comet ZTF is
   indicated at the right, its apparent motion mostly reflecting Earth's
   rotation like the stars. But heading for its closest approach to planet
   Earth on February 1, the comet is also moving significantly with
   respect to the background stars. The diffuse greenish trail of Comet
   ZTF is an almost concentric arc mingled with startrails as it sweeps
   through the long-necked constellation Camelopardalis.

                      Tomorrow's picture: light-weekend
     __________________________________________________________________

       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,
                           NASA Science Activation
                             & Michigan Tech. U.

