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 October 21
    [2]See Explanation. Clicking on the picture will download the highest
                        resolution version available.

                                Quarter Moons
            Image Credit & [3]Copyright: [4]Marcella Giulia Pace

   Explanation: Half way between New Moon and Full Moon is [5]the Moon's
   first quarter phase. That's a quarter of the way around its [6]moonthly
   orbit. At the first quarter phase, half [7]the Moon's visible side is
   illuminated by sunlight. For the Moon's third quarter phase, half way
   between Full Moon and New Moon, sunlight illuminates the other half of
   the visible lunar disk. At both first and third quarter phases, the
   terminator, or shadow line separating the lunar night and day, runs
   down the middle. Near the [8]terminator, long shadows bring lunar
   craters and mountains in to sharp relief, making the quarter phases a
   good time to observe the Moon. But in case you missed some, [9]all the
   quarter phases of the Moon and their calendar dates during 2022 can be
   found in this well-planned array of telephoto images. [10]Of course,
   you can observe a first quarter Moon tonight.

                  International: [11]Observe the Moon Night
                 Tomorrow's picture: ghostly northern lights
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      [12]< | [13]Archive | [14]Submissions | [15]Index | [16]Search |
   [17]Calendar | [18]RSS | [19]Education | [20]About APOD | [21]Discuss |
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     __________________________________________________________________

    Authors & editors: [23]Robert Nemiroff ([24]MTU) & [25]Jerry Bonnell
                                 ([26]UMCP)
          NASA Official: Phillip Newman [27]Specific rights apply.
              [28]NASA Web Privacy Policy and Important Notices
                A service of: [29]ASD at [30]NASA / [31]GSFC,
                         [32]NASA Science Activation
                           & [33]Michigan Tech. U.

References

   1. https://apod.nasa.gov/apod/archivepix.html
   2. https://apod.nasa.gov/apod/image/2310/quartermoon2022date.jpeg
   3. https://apod.nasa.gov/apod/lib/about_apod.html#srapply
   4. https://greenflash.photo/about-me/
   5. https://science.nasa.gov/moon/lunar-phases-and-eclipses/
   6. https://apod.nasa.gov/apod/ap200926.html
   7. https://moon.nasa.gov/inside-and-out/composition/overview/
   8. https://apod.nasa.gov/apod/ap180301.html
   9. https://greenflash.photo/portfolio/all-quarter-moons-of-2022/
  10. https://moon.nasa.gov/moon-observation/daily-moon-guide/
  11. https://moon.nasa.gov/observe-the-moon-night/
  12. https://apod.nasa.gov/apod/ap231020.html
  13. https://apod.nasa.gov/apod/archivepix.html
  14. https://apod.nasa.gov/apod/lib/apsubmit2015.html
  15. https://apod.nasa.gov/apod/lib/aptree.html
  16. https://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search
  17. https://apod.nasa.gov/apod/calendar/allyears.html
  18. https://apod.nasa.gov/apod.rss
  19. https://apod.nasa.gov/apod/lib/edlinks.html
  20. https://apod.nasa.gov/apod/lib/about_apod.html
  21. http://asterisk.apod.com/discuss_apod.php?date=231021
  22. https://apod.nasa.gov/apod/ap231022.html
  23. http://www.phy.mtu.edu/faculty/Nemiroff.html
  24. http://www.phy.mtu.edu/
  25. https://antwrp.gsfc.nasa.gov/htmltest/jbonnell/www/bonnell.html
  26. http://www.astro.umd.edu/
  27. https://apod.nasa.gov/apod/lib/about_apod.html#srapply
  28. https://www.nasa.gov/about/highlights/HP_Privacy.html
  29. https://astrophysics.gsfc.nasa.gov/
  30. https://www.nasa.gov/
  31. https://www.nasa.gov/centers/goddard/
  32. https://science.nasa.gov/learners
  33. http://www.mtu.edu/