I am looking for the information on the percentage illumination of the moon during the different stages of a total lunar eclipse. Is there a database from where I can acquire information of lunar illumination, distance and angle for the July 27th 2018 lunar eclipse for a given location?

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    $\begingroup$ You mean the percent of the moon's surface which is illuminated fully by the sun? Do you want to include the penumbra? What do you mean by angle and distance? $\endgroup$ Nov 21 '18 at 15:54
  • $\begingroup$ Related: What irradiance does the Moon receive during a total lunar eclipse? $\endgroup$
    – Glorfindel
    Nov 22 '18 at 9:42
  • $\begingroup$ Or, are you asking, for example, if the moon is 99.999999% illuminated at the start of the eclipse and 100.000000% at the middle? $\endgroup$ Dec 4 '20 at 18:36

I found some chart regarding this, which is here:


The light level drops from about 50-60% prenumbral phase. It becomes noticeable.

enter image description here

If you want to get the percentage illumination of the Moon during the eclipse, install the Cartes du Ciel and turn on the Earth's shadow. Then you will be able to gauge the percentage value.


enter image description here

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    $\begingroup$ That's a plot of sky brightness, not what was asked. $\endgroup$
    – Mike G
    Dec 4 '20 at 14:37
  • 1
    $\begingroup$ OK I will edit my answer $\endgroup$
    – MKR
    Dec 4 '20 at 15:07

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