It is said that we see about 59% part of the Moon due to libration. However we must be seeing more than that. My logic is as below. Since the Moon's orbit is inclined to the plane of Sun-Earth by 5 1/2 degree, when Moon is at farthest and lowest point below the plane, we can see beyond the North Pole of Moon from the Earth's North pole and similarly when the Moon is above the Sun-Earth plane we can see much beyond South pole of the Moon from Earth's South Pole. Thus we must be seeing more than 59% due to inclined orbit of Moon.

  • $\begingroup$ I think you're correct, but could you do the math and compute how much more we should be able to see? I suspect it's a small amount.given the ratio of the moon's size to its distance. $\endgroup$ – user21 Jan 18 at 1:55
  • $\begingroup$ Yes, I am doing Maths. but I do not know how to attach a photo as I have done it on plain paper with sketch. $\endgroup$ – Mohan Mone Jan 18 at 2:08
  • $\begingroup$ Just scan and upload, or maybe use something like geogebra.org if you want a cleaner looking diagram $\endgroup$ – user21 Jan 18 at 2:12
  • $\begingroup$ Out of curiosity, what causes the libration that you mentioned? ;-) $\endgroup$ – JohnHoltz Jan 18 at 2:14
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    $\begingroup$ You calculated one of the effects (#3). You now need to calculate the other two effects and add them to 50%. What does the total give? You should find out that 59% already includes the 6.6% that you calculated. $\endgroup$ – JohnHoltz Jan 18 at 15:08

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