Astronomy Picture of the Day

   [1]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 April 30
   [2]An oblong moon is shown in very muted colors, appearing almost gray.
   The background is deep space and completely dark at this short exposure
       time. Please see the explanation for more detailed information.

                        Saturn's Moon Helene in Color
    Image Credit: [3]NASA, [4]JPL-Caltech, [5]SSI; Processing: [6]Daniel
                                 Macháček

   Explanation: Although its colors may be subtle, Saturn's moon Helene is
   an enigma in any light. The [7]moon was imaged in [8]unprecedented
   detail in 2012 as the [9]robotic Cassini spacecraft orbiting Saturn
   [10]swooped to within a single Earth diameter of the [11]diminutive
   moon. Although conventional craters and hills [12]appear, the [13]above
   [14]image also [15]shows terrain that appears unusually smooth and
   streaked. [16]Planetary astronomers are inspecting these detailed
   images of [17]Helene to [18]glean clues about the origin and evolution
   of the 30-km across floating iceberg. [19]Helene is also unusual
   because it circles Saturn just ahead of the large moon [20]Dione,
   making it one of only four known [21]Saturnian moons to occupy a
   gravitational well known as a stable [22]Lagrange point.

                    Tomorrow's picture: stars with colors
     __________________________________________________________________

      [23]< | [24]Archive | [25]Submissions | [26]Index | [27]Search |
   [28]Calendar | [29]RSS | [30]Education | [31]About APOD | [32]Discuss |
                                    [33]>
     __________________________________________________________________

    Authors & editors: [34]Robert Nemiroff ([35]MTU) & [36]Jerry Bonnell
                                 ([37]UMCP)
          NASA Official: Phillip Newman [38]Specific rights apply.
              [39]NASA Web Privacy Policy and Important Notices
                A service of: [40]ASD at [41]NASA / [42]GSFC,
                         [43]NASA Science Activation
                           & [44]Michigan Tech. U.

References

   1. https://apod.nasa.gov/apod/archivepix.html
   2. https://apod.nasa.gov/apod/image/2304/helene2_cassini_1024.jpg
   3. https://www.nasa.gov/
   4. https://www.jpl.nasa.gov/
   5. https://ciclops.org/
   6. https://twitter.com/danielmachacek_
   7. https://www.planetary.org/articles/04201100
   8. https://www.nasa.gov/mission_pages/cassini/whycassini/cassini20110620.html
   9. https://solarsystem.nasa.gov/missions/cassini/mission/spacecraft/cassini-orbiter/
  10. https://www.youtube.com/watch?v=HiHSM-_fes4
  11. https://solarsystem.nasa.gov/moons/saturn-moons/helene/in-depth/
  12. https://apod.nasa.gov/apod/ap190615.html
  13. https://www.planetary.org/multimedia/space-images/helene-in-color.html
  14. https://photojournal.jpl.nasa.gov/catalog/PIA12773
  15. https://www.nasa.gov/mission_pages/cassini/whycassini/cassini20100308.html
  16. http://www.planetary.org/blogs/emily-lakdawalla/2011/3072.html
  17. http://en.wikipedia.org/wiki/Helene_(moon)
  18. https://www.rover.com/blog/wp-content/uploads/curious-cat-looking-in-a-box-960x540.jpg
  19. https://apod.nasa.gov/apod/ap951010.html
  20. https://apod.nasa.gov/apod/ap121105.html
  21. https://solarsystem.nasa.gov/moons/saturn-moons/overview/
  22. https://en.wikipedia.org/wiki/Lagrange_point
  23. https://apod.nasa.gov/apod/ap230429.html
  24. https://apod.nasa.gov/apod/archivepix.html
  25. https://apod.nasa.gov/apod/lib/apsubmit2015.html
  26. https://apod.nasa.gov/apod/lib/aptree.html
  27. https://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search
  28. https://apod.nasa.gov/apod/calendar/allyears.html
  29. https://apod.nasa.gov/apod.rss
  30. https://apod.nasa.gov/apod/lib/edlinks.html
  31. https://apod.nasa.gov/apod/lib/about_apod.html
  32. https://asterisk.apod.com/discuss_apod.php?date=230430
  33. https://apod.nasa.gov/apod/ap230501.html
  34. http://www.phy.mtu.edu/faculty/Nemiroff.html
  35. http://www.phy.mtu.edu/
  36. https://antwrp.gsfc.nasa.gov/htmltest/jbonnell/www/bonnell.html
  37. http://www.astro.umd.edu/
  38. https://apod.nasa.gov/apod/lib/about_apod.html#srapply
  39. https://www.nasa.gov/about/highlights/HP_Privacy.html
  40. https://astrophysics.gsfc.nasa.gov/
  41. https://www.nasa.gov/
  42. https://www.nasa.gov/centers/goddard/
  43. https://science.nasa.gov/learners
  44. http://www.mtu.edu/