<p>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.</p>

CC BY-SA 4.0
2020-01-18T02:08:31.063Z
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.
Mohan Mone
CC BY-SA 4.0
2020-01-18T02:14:39.257Z
Out of curiosity, what causes the libration that you mentioned? ;-)
JohnHoltz
CC BY-SA 4.0
2020-01-18T05:24:12.010Z
Why should the location of the Sun make any difference? If we suddenly miraculously removed the Sun, the (relative) motions and orientations of Earth/Moon would be virtually unchanged.
Keith McClary
CC BY-SA 4.0
2020-01-18T08:55:20.077Z
@Keith McClary but what about lunar phases? It is a "three bodies" problem, after all.
Alchimista
CC BY-SA 4.0
2020-01-18T11:15:44.963Z
@Alchimista - That's lighting. It has zero impact on what we can see. The logic in this question is incorrect.
David Hammen
CC BY-SA 4.0
2020-01-18T11:32:05.360Z
@JohnHoltz - There are three causes. (1) The Moon's orbit has a non-zero eccentricity. (2) The Moon's rotation axis is not quite aligned with its orbit axis. (3) We observe the Moon from the Earth's surface rather than from its center, giving us slightly different perspective at moonrise vs moonset.
David Hammen
CC BY-SA 4.0
2020-01-18T12:18:53.127Z
As p er my calculation we should see 3.3% additional part of North Hemisphere of Moon when Moon is below the ecliptic plane and similarly 3.3% of southern hemisphere of Moon when the Moon is above ecliptic plane. Thus total 6.6% additional to 59 % due to libration = Total 65.6%
Mohan Mone
CC BY-SA 4.0
2020-01-18T15:08:48.200Z
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.
JohnHoltz
CC BY-SA 4.0
2020-01-20T19:07:21.940Z
Pretty sure there are answers to this over at  SpaceExploration.SE
Carl Witthoft
<observational-astronomy>
We should be seeing more than 59% of the Moon
Mohan Mone
# We should be seeing more than 59% of the Moon

(Asked by: username_0 on 2020-01-17)

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.

**Tags:** observational-astronomy

> **Comments:**
> **username_0**: 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.  
> **username_1**: Out of curiosity, what causes the libration that you mentioned? ;-)  
> **username_2**: Why should the location of the Sun make any difference? If we suddenly miraculously removed the Sun, the (relative) motions and orientations of Earth/Moon would be virtually unchanged.  
> **username_3**: @username_2 but what about lunar phases? It is a "three bodies" problem, after all.  
> **username_4**: @username_3 - That's lighting. It has zero impact on what we can see. The logic in this question is incorrect.  
> **username_4**: @username_1 - There are three causes. (1) The Moon's orbit has a non-zero eccentricity. (2) The Moon's rotation axis is not quite aligned with its orbit axis. (3) We observe the Moon from the Earth's surface rather than from its center, giving us slightly different perspective at moonrise vs moonset.  
> **username_0**: As p er my calculation we should see 3.3% additional part of North Hemisphere of Moon when Moon is below the ecliptic plane and similarly 3.3% of southern hemisphere of Moon when the Moon is above ecliptic plane. Thus total 6.6% additional to 59 % due to libration = Total 65.6%  
> **username_1**: 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.  
> **username_5**: Pretty sure there are answers to this over at  SpaceExploration.SE  

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