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.

                               2022 February 6
   [2]The featured image shows a full face of Earth as photographed by the
    Apollo 17 Crew in 1972. Please see the explanation for more detailed
                                information.

                              Blue Marble Earth
                  Image Credit: [3]NASA, [4]Apollo 17 Crew

   Explanation: Welcome to planet Earth, the third planet from a star
   named the Sun. The [5]Earth is shaped like a [6]sphere and [7]composed
   mostly of rock. Over 70 percent of the [8]Earth's surface is water. The
   planet has a relatively [9]thin atmosphere composed mostly of
   [10]nitrogen and [11]oxygen. The [12]featured picture of Earth, dubbed
   [13]The Blue Marble, was [14]taken from [15]Apollo 17 in 1972 and
   features [16]Africa and [17]Antarctica. It is thought to be one of the
   most [18]widely distributed photographs of any kind. [19]Earth has a
   single large [20]Moon that is about 1/4 of its diameter and, from the
   planet's surface, is seen to have almost exactly the [21]same angular
   size as the Sun. With its [22]abundance of liquid water, Earth supports
   a large [23]variety of life forms, including potentially intelligent
   species such as [24]dolphins and [25]humans. Please [26]enjoy your stay
   on planet Earth.

                      Tomorrow's picture: galactic rain
     __________________________________________________________________

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

    Authors & editors: [38]Robert Nemiroff ([39]MTU) & [40]Jerry Bonnell
                                 ([41]UMCP)
          NASA Official: Phillip Newman [42]Specific rights apply.
              [43]NASA Web Privacy Policy and Important Notices
                A service of: [44]ASD at [45]NASA / [46]GSFC
                           & [47]Michigan Tech. U.

References

   1. https://apod.nasa.gov/apod/archivepix.html
   2. https://apod.nasa.gov/apod/image/2202/bluemarble_apollo17_3000.jpg
   3. https://www.nasa.gov/
   4. https://www.nasa.gov/mission_pages/apollo/missions/apollo17.html
   5. https://solarsystem.nasa.gov/planets/earth/in-depth/
   6. https://www.geogebra.org/m/gsXuhRrs
   7. https://en.wikipedia.org/wiki/Earth#Chemical_composition
   8. https://www.usgs.gov/special-topics/water-science-school/science/how-much-water-there-earth
   9. https://www.nasa.gov/multimedia/imagegallery/image_feature_1529.html
  10. https://periodic.lanl.gov/7.shtml
  11. https://periodic.lanl.gov/8.shtml
  12. https://www.nasa.gov/content/blue-marble-image-of-the-earth-from-apollo-17
  13. https://en.wikipedia.org/wiki/The_Blue_Marble
  14. https://apolloinrealtime.org/17/?t=005:49:47
  15. https://solarsystem.nasa.gov/missions/apollo-17/in-depth/
  16. https://en.wikipedia.org/wiki/Africa
  17. https://en.wikipedia.org/wiki/Antarctica
  18. https://earthobservatory.nasa.gov/features/BlueMarble/BlueMarble_history.php
  19. https://earthobservatory.nasa.gov/features/earth-book-2019
  20. https://solarsystem.nasa.gov/moons/earths-moon/overview/
  21. https://apod.nasa.gov/apod/ap160501.html
  22. https://apod.nasa.gov/apod/ap160911.html
  23. https://science.nasa.gov/solar-system/big-questions/how-did-life-begin-and-evolve-earth-and-has-it-evolved-elsewhere-solar-system
  24. https://us.whales.org/whales-dolphins/how-intelligent-are-whales-and-dolphins/
  25. https://apod.nasa.gov/apod/ap190818.html
  26. https://www.jwj.org/wp-content/uploads/2015/01/happy-kitten-kittens-5890512-1600-12001-1024x768.jpg
  27. https://apod.nasa.gov/apod/ap220205.html
  28. https://apod.nasa.gov/apod/archivepix.html
  29. https://apod.nasa.gov/apod/lib/apsubmit2015.html
  30. https://apod.nasa.gov/apod/lib/aptree.html
  31. https://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search
  32. https://apod.nasa.gov/apod/calendar/allyears.html
  33. https://apod.nasa.gov/apod.rss
  34. https://apod.nasa.gov/apod/lib/edlinks.html
  35. https://apod.nasa.gov/apod/lib/about_apod.html
  36. http://asterisk.apod.com/discuss_apod.php?date=220206
  37. https://apod.nasa.gov/apod/ap220207.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. https://apod.nasa.gov/apod/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/