This website (page 26) claims that full-earth-shine on the moon is 100 times greater than full-moon-shine on earth. The figure 100 is made up of the difference between the size of the earth and the moon, multiplied with the difference of their albedos. The earth is 13.45 times bigger than the moon. 100 divided by 13.45 equals 7.43. 7.43 multiplied with 0.12 (the moons albedo) equals 0.8916. Thus, he must have calculated with an earth albedo of 0.8916. But that might be a miscalculation. To figure that out the following question needs to be asked:

What is the highest albedo of the earth's surface facing the sun ever measured? Note, the question is not about the albedo of certain sections of the earth, but about the whole side of the earth that is facing the sun.

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    $\begingroup$ This is starting to verge on the mono-manical. astronomy.stackexchange.com/questions/8133/… The Earth's albedo is about 0.3, but can vary from time to time. It is also something that isn't easy to "measure" So perhaps the author of this one article is "simply wrong". See also earthobservatory.nasa.gov/images/84499/measuring-earths-albedo $\endgroup$
    – James K
    Feb 20, 2021 at 8:42
  • $\begingroup$ Astronomers don't make detailed, granular albedo measurements of the Earth, however Earth Scientists do! This one is off-topic here but nicely on-topic in Earth Science SE where they talk about satellite measurements of Earth all the time! $\endgroup$
    – uhoh
    Feb 20, 2021 at 9:11
  • $\begingroup$ As the author says and as I have amplified in your other question, the assumed Bond albedo is not responsible for the additional factor of $\sim 2$. It is absorption and the directional properties (non Lambertian nature) of the reflection. $\endgroup$
    – ProfRob
    Feb 20, 2021 at 10:53
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    $\begingroup$ @uhoh. en.m.wikipedia.org/wiki/List_of_Mars_orbiters $\endgroup$ Feb 21, 2021 at 2:12
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    $\begingroup$ I think it might be true - Earth has much higher albedo (count with 2), Moon has no atmosphere (count with 2) and the radius of the Earth is 6x bigger (x36). It roughly matches. Surprising. $\endgroup$
    – peterh
    Feb 22, 2021 at 10:12


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