In a message dated 99/12/11 10:53:47, [EMAIL PROTECTED] quotes:

>Since a full moon on the winter solstice is occurring in conjunction
>with a lunar perigee (point in the moon's orbit that is closest to
>Earth), the moon will appear about 14% larger than it does at apogee.
>This will make it appear brighter. Also, this will be the closest lunar
>perigee of the year. 
>
>The Earth is also several million miles closer to the sun, than in the
>summer.  Thus the sunlight striking the moon is about 7% stronger,
>making it still brighter.

Laying a coupla numbers (from the CRC) on it:

earth, in kilometers
apogee  1.5207E8
perigee 1.4707E8

(1.5207/1.4707)^2 = 1.069

moon, in kilometers
apogee  4.0551E5
perigee 3.6330E5

(4.0551/3.6330)^2 = 1.246

total 1.069*1.246 = 1.288

ln 1.288 / ln 2 = .37 stops

I don't know if you can see .37 stops difference or not.
So it will appear brighter but I think a clear night 
would be more important to brightness.  Of course if 
there is snow on the ground, then dark objects will have
high contrast and contrast is the name of the game in
resolution.  So with the increased contrast and the
reflectance of the snow, the night may appear much 
brighter.

John B

PS: 4.0551/3.6330 = 1.116, rather than 1.14

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