What Are the Individual Libration Percentages of the Moon?

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Libration allows observers to see about 9% of the Moon's far side, with individual contributions from different types of libration. NASA provides specific figures for geometrical librations: 6.5° for longitude, 7.7° for latitude, and 1° for diurnal, along with 1.5° for physical libration. Based on these angles, it is estimated that longitude contributes 4%, latitude 3.4%, diurnal 0.5%, and physical libration 0.8% to the visibility of the far side. Diurnal libration specifically accounts for an additional 2% visibility due to the Earth's rotation. The discussion highlights the challenge in finding precise individual percentages for each type of libration.
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I understand that Libration allows us to see a total of about 9% of the far side of the moon, but what are the individual percentages of the far side of the moon that longitude, latitude, Diurnal and physical Libration allows us to see?

I can't seem to "Google-up" these individual percentages, but surly this is known information, and it seems odd to me that it's not readily available.
 
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Hi Timoothy! :smile:

NASA gives figures of 6.5° 7.7° and 1° for the "geometrical" librations and 1.5° for "physical" libration are given at http://www-istp.gsfc.nasa.gov/stargaze/Smoon4.htm" :wink:

(btw. i found this by googling "Patrick Moore" :biggrin:)
 
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tiny-tim said:
Hi Timoothy! :smile:

NASA gives figures of 6.5° 7.7° and 1° for the "geometrical" librations and 1.5° for "physical" libration are given at

http://www-istp.gsfc.nasa.gov/stargaze/Smoon4.htm"

Hi tt, thanks for your reply.

I had read that page before but moved on since I wasn't sure if they were comparing apples to apples with the "degrees" they were talking about, but assuming the degrees they give ( 7.7, 6.5, 1 and 1.5) are the totals that the different types of Libration allows us to see of the far side of the moon, then Longitude is 4%, Latitude is 3.4%, Diurnal is .5% and Physical is .8%.
 
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https://www.physicsforums.com/showpost.php?p=145092&postcount=14

"Diuranl Libration is due the fact that over the course of time from moonrise to moonset we see the Moon from different angles as the Earth rotates. Thus allows us to see about 2% more of the Moon."


Hi Janus
How did you come up with the figure of 2% for Diurnal Libration?
 
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