116 FAQs about the Moon (The Astronomy Cafe)

 

Basic Facts: NASA/NSSDC Fact Sheet, Links

Missions: Prospector,Ranger,Orbiter,Surveyor,Apollo,Clementine

Calculators: Apogee and Perigee

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  1. Is the rotation speed of the Earth slowing down?
  2. Why does the Moon move on a circular orbit?
  3. Is there an archive of lunar perigee and apogee distances for the future?
  4. Why isn't the Earth always in the same spot in the Lunar sky all the time?
  5. What do we now know about the patches of ice on the Moon?
  6. Is the Moon moving away from the Earth?
  7. Have gold, silver or diamonds been found on the Moon?
  8. How do astronomers know that the center of gravity of the Moon is 2 kilometers away from its geometric center?
  9. Was the center of the far side of the Moon ever facing Earth?
  10. How long can the Moon hold an atmosphere like the Earth's?
  11. Were there ever lakes on the Moon?
  12. How will gamma rays be used to detect water ice on the Moon?
  13. How far does the Moon travel in its orbit?
  14. Why did Galileo say the Moon was made of a sand-like material?
  15. How long is a day on the Moon?
  16. How hot is the Moon?
  17. Is the brightness of the Half Moon really 1/9 the Full Moon?
  18. What is the circumference of the Moon?
  19. Why do we only see one side of the Moon?
  20. Are there places on the Earth where the Moon looks biggest?
  21. Would the crescent Moon appear oriented differently in different parts pf the Earth?
  22. How and why does the Moon shine?
  23. Can you buy land on the Moon?
  24. If I stood on the Moon, would I see the Earth?
  25. Why aren't lunar craters as deep as their diameters would lead you to expect?
  26. Why wasn't the ice on the Moon discovered long ago?
  27. Is there such a thing as Moon germs?
  28. Why does the gravity of the Earth and Moon balance at 40,000 miles from the Moon?
  29. How is it possible for ice to exist on the Moon without sublimating away?
  30. What causes lunar libration?
  31. What would happen to the Moon if the Earth changed its mass by 1/2 or 1/4?
  32. Does the Moon change its position the way the Sun does from winter to summer?
  33. Does our Moon have a technical name?
  34. Was there any activity on the Moon on October 26, 1996?
  35. If the Earth's rotation were reversed, what would happen to the Moon?
  36. When we see the Moon in the daytime in North America, do chinese observers see it at night time?
  37. How fast does the Moon rotate and revolve?
  38. Can other moons in the solar system get synched with their planets rotation?
  39. Have any new craters been seen in the 100 years of lunar photographs taken from Earth?
  40. Where can I get the longitude of the Moon's perigee?
  41. Do the nodes of the Moon's orbit where it crosses the Ecliptic plane, move?
  42. Has anyone used a powerful telescope to look at the old Apollo landing sites?
  43. Is it true that the Moon is moving away from the Earth?
  44. Will the Earth always appear in the same location in the sky as seen from the Moon?
  45. For part of its orbit, the Moon is close to the Sun. Why doesn't the Moon escape the Earth then?
  46. Is there a feature on the Moon called the 'lunar bridge'?
  47. Will the Moon be in Virgo on September 13, 1996?
  48. What would happen if the Moon suddenly left orbit around the Earth?
  49. What effect did the Moon have on the Earth during the first few billion years?
  50. How far away from the Earth was the Moon first formed?
  51. Is there an approximate way to calculate the distance to the Moon for any given day?
  52. Is the Moon always opposite from the Sun in the sky?
  53. In what plane does the Moon orbit the Earth?
  54. How high can you jump on the Moon?
  55. Why is the lunar month exactly equal to the human female menstrual cycle?
  56. Why does the Moon appear yellow during certain times of the year, like Easter?
  57. At what depth do moonquakes occur?
  58. Why does the Moon rise 50 minutes later each day?
  59. How many minerals are known to exist on the Moon?
  60. How many pounds of Moon rocks were brought back to earth?
  61. Why is it that you can see the Moon in the daytime during some time of the month, but not at other times?
  62. Is there a simple way to track the Moon at night to show how it travels across the sky?
  63. Can sound travel through the thin atmosphere of the Moon?
  64. Are there any active volcanoes on the Moon?
  65. Has anyone ever seen a crater form on the Moon?
  66. Why do some lunar craters like Tycho and Copernicus have rays?
  67. What equations are needed to predict the rise and setting of the Moon from any location?
  68. What are the dark spots on the Moon?
  69. Why is the Moon synchronized so that it exactly shows the same face to the Earth all the time?
  70. What is the physiological process behind the Moon Illusion?
  71. What is the brightest star that can ever be occulted by the Moon?
  72. How was the Moon formed?
  73. Where can I get information about the Linne crater in Mare Serenitatus?
  74. Which way does the Moon go around the Earth?
  75. Do you know anything really interesting about the Moon?
  76. Is there a place on the Earth where you will never see the Moon?
  77. Is the orbit of the Moon expanding?
  78. How did Aristarchus determine the angle between the quarter phase Moon and the Sun?
  79. Will there be an interesting event involving the Moon and a planet on February 19, 1996?
  80. Where is the barycenter of the Earth-Moon system located?
  81. Does the Moon have an atmosphere?
  82. Could you give the names and locations of 5 craters and 5 seas on the Moon?
  83. What is the biggest and smallest crater on the Moon?
  84. What is the exact orbital period of the Moon?
  85. Is there really a dark side to the Moon?
  86. What direction does the Moon travel in the sky from day to day?
  87. On March 21, 4713 BC the Sun rose 12 degrees south of east. Is there a problem with this?
  88. What is the distance to the Moon?
  89. How large an effect is atmospheric refraction on the location of the Moon?
  90. Where can I get a computer readable copy of Brown's Lunar Theory?
  91. Can I use lunar daily position information from the USA to predict what I would see from Japan?
  92. How often are planets occulted by the Moon?
  93. Could you explain what causes the Moon's synchronous rotation?
  94. There was a large ring around the Moon one night. What was it?
  95. Will the Moon be in the night sky between 3 January and 19 January, 1996?
  96. Why does the Moon look the color of orange sherbet when it rises?
  97. What is the relationship between the Moon's rotation and revolution periods?
  98. What is the history behind the Man in the Moon?
  99. What was Tom Hanks doing in Apollo 13 holding his thumb to the Moon?
  100. Why does the Moon seem to be in different parts of the sky every time I look?
  101. Can we see the back side of the Moon?
  102. Why does the Moon seem bigger on the horizon than high up in the sky?
  103. If the Moon has an 11 year cycle North and South of the ecliptic, where is it in its current cycle now?
  104. Where can I get information about the Earth's relationship to the Sun and Moon?
  105. What physical mechanism causes the Moon to always show the same face to the Earth?
  106. What is the term for the point between Earth and Moon where the gravitational forces are equal?
  107. What is it about the lunar surface that makes it so bright from the Earth?
  108. The Earth- Moon system is almost a double planet. What would have happened if Earth had no Moon?
  109. Will we ever go back to the Moon?
  110. Why do the lunar sidereal and synodic months have different lengths?
  111. In what direction does the Moon move in the sky relative to the stars?
  112. What is the Moon's speed per day relative to the stars?
  113. How long is the lunar month?
  114. How many layers make up the Moon's mass?
  115. How is it possible to see the Moon in the daytime?
  116. Does the Moon loose energy while orbiting the Earth?


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