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Science Light of Elune, Help Me Understand Moonlight

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SUSslimey
post Jan 19 2011, 03:44 AM


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QUOTE(faceless @ Jan 18 2011, 03:34 PM)
Thanks Befitozi and  Dkk for the explanation of the word "reflect" from a science perspective. Mgjg your links on reflectivity and emissivity had been helpful. I am still not clear on this subject. I think the intensity of the light from the moon is very high to be visible on earth. The light from a two battery torch light is of no comparison. It had made me wonder why astronauts were not glared by the moonlight.
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http://en.wikipedia.org/wiki/Albedo

albedo of moon around 0.12 which is about that of asphalt
albedo of snow around 0.9


SUSslimey
post Jan 20 2011, 04:30 AM


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QUOTE(dkk @ Jan 19 2011, 10:13 PM)
The moon's albedo is 0.12. The earth's albedo is 0.3. If you think the moon seems bright from here, the earth looks even brighter when you're standing on the moon.

Add to that the fact that the earth is much larger, it throws a lot more reflected sunlight on to the moon, than the other way around.

The moon only seems so bright because the sky around it is dark. Actually it's not all that bright. I can think of two ways to demonstrate this.

1) Find a street light near your house. Walk around until you see the moon in the sky near where the light appears to you. You would see that the light is much much brighter than the moon

2) Look into a torch light while you are in a dark room at night. The torch light seems very bright. Wait 12 hours until the sun is up. Go out. Turn on the torch light and look at it again. It would seem very dim.
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nice analogies....

ya....it's about perception and relativity.....

another point to add.
during the dark, the pupils of the eye dilate to allow more light to enter the retina, which will give you the perception that it is brighter than it actually is.

 

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