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How do the moon's & earth's orbital planes intersect?

  1. Dec 31, 2005 #1


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    Consider the earth's orbit around the sun to be in a plane A and the moon's orbit around the earth to be in a plane B. How do these planes intersect? Are they parallel or perpendicular? At what angle do they intersect themselves? Does the angle stay the same, or does it vary.
  2. jcsd
  3. Dec 31, 2005 #2


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    The Moon's orbit is inclined roughly 5 degrees to the ecliptic. The ecliptic is defined to be the plane of the Earth's orbit. The orientation rotates one complete revolution every 18+ years. The argument of perigee rotates one complete revolution every ~9 years. Click the link for an animation. This is viewed from the ecliptic, so if it were shown, the Earth's orbital plane would be a horizontal line through the center of the Earth.

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