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 April 17
    [2]The featured image shows a the NASA space shuttle approaching the
       International Space Station with the Earth's atmosphere in the
    background. Please see the explanation for more detailed information.

                             Shuttle Over Earth
                Image Credit: [3]NASA, [4]Expedition 22 Crew

   Explanation: What's that approaching? Astronauts on board the
   [5]International Space Station in 2010 first saw it far in the
   distance. Soon it enlarged to become a [6]dark silhouette. As it came
   even closer, the [7]silhouette appeared to be a spaceship. Finally, the
   object revealed itself to be the [8]Space Shuttle Endeavour, and it
   soon docked as expected with the Earth-orbiting space station.
   [9]Pictured here, Endeavour was imaged near Earth's horizon as it
   approached, where several layers of the [10]Earth's atmosphere were
   visible. Directly behind the shuttle is the [11]mesosphere, which
   appears blue. The atmospheric layer that appears white is the
   [12]stratosphere, while the orange layer is Earth's [13]Troposphere.
   Together, these thin layers of air -- collectively spanning less than 2
   percent of [14]Earth's radius -- [15]sustain us all in many ways,
   including providing [16]oxygen to breath and a barrier to [17]dangerous
   radiations from space.

                    Coming up Friday: [18]Earth Day 2022
                       Tomorrow's picture: steppe sky
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      [19]< | [20]Archive | [21]Submissions | [22]Index | [23]Search |
   [24]Calendar | [25]RSS | [26]Education | [27]About APOD | [28]Discuss |
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     __________________________________________________________________

    Authors & editors: [30]Robert Nemiroff ([31]MTU) & [32]Jerry Bonnell
                                 ([33]UMCP)
          NASA Official: Phillip Newman [34]Specific rights apply.
              [35]NASA Web Privacy Policy and Important Notices
                A service of: [36]ASD at [37]NASA / [38]GSFC
                           & [39]Michigan Tech. U.

References

   1. https://apod.nasa.gov/apod/archivepix.html
   2. https://apod.nasa.gov/apod/image/2204/shuttleAtm_nasa_6048.jpg
   3. https://www.nasa.gov/
   4. https://www.nasa.gov/mission_pages/station/expeditions/expedition22/index.html
   5. https://www.nasa.gov/mission_pages/station/main/index.html
   6. https://en.wikipedia.org/wiki/Silhouette
   7. https://apod.nasa.gov/apod/ap220411.html
   8. https://californiasciencecenter.org/exhibits/endeavour-experience/space-shuttle-endeavour
   9. https://www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts130/multimedia/fd3/Image_Gallery_Collection_archive_1.html
  10. https://spaceplace.nasa.gov/atmosphere/en/
  11. https://spaceplace.nasa.gov/mesosphere/en/
  12. https://en.wikipedia.org/wiki/Stratosphere
  13. https://en.wikipedia.org/wiki/Troposphere
  14. https://apod.nasa.gov/apod/ap220206.html
  15. https://www1.racgp.org.au/getattachment/1ba46046-2868-48c8-99d8-a35430b711c9/attachment.aspx
  16. https://theimportantsite.com/10-reasons-why-oxygen-is-important/
  17. https://www.nasa.gov/analogs/nsrl/why-space-radiation-matters
  18. https://www.jpl.nasa.gov/edu/events/2022/4/22/celebrate-earth-day-with-education-resources-from-nasa/
  19. https://apod.nasa.gov/apod/ap220416.html
  20. https://apod.nasa.gov/apod/archivepix.html
  21. https://apod.nasa.gov/apod/lib/apsubmit2015.html
  22. https://apod.nasa.gov/apod/lib/aptree.html
  23. https://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search
  24. https://apod.nasa.gov/apod/calendar/allyears.html
  25. https://apod.nasa.gov/apod.rss
  26. https://apod.nasa.gov/apod/lib/edlinks.html
  27. https://apod.nasa.gov/apod/lib/about_apod.html
  28. http://asterisk.apod.com/discuss_apod.php?date=220417
  29. https://apod.nasa.gov/apod/ap220418.html
  30. http://www.phy.mtu.edu/faculty/Nemiroff.html
  31. http://www.phy.mtu.edu/
  32. https://antwrp.gsfc.nasa.gov/htmltest/jbonnell/www/bonnell.html
  33. http://www.astro.umd.edu/
  34. https://apod.nasa.gov/apod/lib/about_apod.html#srapply
  35. https://www.nasa.gov/about/highlights/HP_Privacy.html
  36. https://astrophysics.gsfc.nasa.gov/
  37. https://www.nasa.gov/
  38. https://www.nasa.gov/centers/goddard/
  39. http://www.mtu.edu/