                         Astronomy Picture of the Day

                         Astronomy Picture of the Day

    Discover the cosmos! [1] Each day a different image or photograph of our
 fascinating universe is featured, along with a brief explanation written by a
                           professional astronomer.

                               2018 September 3
                                      [2]
                      Aurora around Saturn's North Pole
  Image Credit [3] : NASA [4] , ESA [5] , Hubble [6] , OPAL Program [7] , J.
         DePasquale [8] (STScI [9] ), L. Lamy [10] (Obs. Paris [11] )

Explanation: Are Saturn's auroras like Earth's? To help answer this question,
the Hubble Space Telescope [12]  and the Cassini spacecraft [13]  monitored
Saturn's North Pole simultaneously during Cassini's final orbits [14] around
the gas giant in September 2017. During this time, Saturn [15] 's tilt caused
its North Pole to be clearly visible [16]  from Earth. The featured image [17]
 is a composite of ultraviolet images [18]  of aurora and optical images of
Saturn's clouds and rings, all taken recently by Hubble. Like on Earth,
Saturn's northern auroras can make total or partial rings [19]  around the
pole. Unlike on Earth, however, Saturn's auroras [20]  are frequently spirals
-- and more likely to peak in brightness just before midnight and dawn. In
contrast to Jupiter's auroras [21] , Saturn's auroras [22]  appear better
related to connecting Saturn's internal magnetic field to the nearby,
variable, solar wind [23] . Saturn's southern auroras [24] were similarly
imaged back in 2004 when the planet's South Pole [25]  was clearly visible to
Earth.

                    Teachers: APOD in the Classroom [26]
                      Tomorrow's picture: moon vs volcano

-------------------------------------------------------------------------------
< [27] | Archive [28] | Submissions [29] | Index [30] | Search [31] | Calendar
  [32] | RSS [33] | Education [34] | About APOD [35] | Discuss [36] | > [37]
-------------------------------------------------------------------------------

    Authors & editors: Robert Nemiroff [38] (MTU [39] ) & Jerry Bonnell [40]
                                  (UMCP [41] )
          NASA Official:  Phillip Newman Specific rights apply [42] .
              NASA Web Privacy Policy and Important Notices [43]
              A service of: ASD [44]  at NASA [45]  / GSFC [46]
                           & Michigan Tech. U. [47]
----------
Site notes:
  [1] archivepix.html
  [2] image/1809/SaturnAurora_Hubble_2215.jpg
  [3] https://www.spacetelescope.org/copyright/
  [4] https://www.nasa.gov/
  [5] http://www.esa.int/
  [6] https://www.nasa.gov/mission_pages/hubble/main/index.html
  [7] https://archive.stsci.edu/prepds/opal/
  [8] http://jdepasquale.com/
  [9] http://www.stsci.edu/who-we-are
  [10] https://www.iau.org/administration/membership/individual/16559/
  [11] https://www.obspm.fr/
  [12] https://www.nasa.gov/mission_pages/hubble/story/index.html
  [13] https://saturn.jpl.nasa.gov/mission/about-the-mission/summary/
  [14] ap170125.html
  [15] https://solarsystem.nasa.gov/planets/saturn/overview/
  [16] ap150621.html
  [17] https://www.spacetelescope.org/images/heic1815a/
  [18] https://science.nasa.gov/ems/10_ultravioletwaves
  [19] ap081119.html
  [20] https://en.wikipedia.org/wiki/Magnetosphere_of_Saturn#Aurorae
  [21] ap160711.html
  [22] https://www.spacetelescope.org/news/heic1815/
  [23] https://en.wikipedia.org/wiki/Solar_wind
  [24] ap050219.html
  [25] ap050222.html
  [26] https://apod.nasa.gov/apod/lib/apodclass.html
  [27] ap180902.html
  [28] archivepix.html
  [29] lib/apsubmit2015.html
  [30] lib/aptree.html
  [31] https://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search
  [32] calendar/allyears.html
  [33] /apod.rss
  [34] lib/edlinks.html
  [35] lib/about_apod.html
  [36] http://asterisk.apod.com/discuss_apod.php?date=180903
  [37] ap180904.html
  [38] http://www.phy.mtu.edu/faculty/Nemiroff.html
  [39] http://www.phy.mtu.edu/
  [40] https://antwrp.gsfc.nasa.gov/htmltest/jbonnell/www/bonnell.html
  [41] http://www.astro.umd.edu/
  [42] lib/about_apod.html#srapply
  [43] https://www.nasa.gov/about/highlights/HP_Privacy.html
  [44] https://astrophysics.gsfc.nasa.gov/
  [45] https://www.nasa.gov/
  [46] https://www.nasa.gov/centers/goddard/
  [47] http://www.mtu.edu/
