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Name: Bruce
Status: other
Grade: other
Location: NV
Country: N/A
Date: 1/25/2006


Question:
Is it possible to actually see the Moon slowly rotating, through a telescope while standing on Earth?


Replies:
Hi Bruce

Yes, you can, but you would have to watch the moon very carefully for a full month. What you are discussing is called lunar longitudinal libration. Although the moon is in synchronous rotation and shows the same face to the earth, its slightly elliptic orbit allows us to see eight degrees of extra face on its right and left side during its perigee and apogee, respectively. Hope this helps.

Robert Froehlich


Only very slightly. Gravity has caused the rotational period (about its polar axis), and the orbital period (about the earth's orbital axis) to be synchronous so that except for a little wobble, the part of the moon that faces the earth is always the same. This is difficult to describe verbally, but if you do a 'Google' search on term(s) like "moon synchronous orbit" or similar you will find many sites with pictures and diagrams explaining synchronous orbits.

Vince Calder



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