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Old 09-05-2017, 12:25 AM
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The Lone Ranger The Lone Ranger is offline
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Default Re: North American Solar eclipse 8/21/2017

Yup. The Moon's average albedo is 0.12; the maria are darker, whereas the lunar uplands are somewhat lighter. Despite the variability, even the "brightest" parts of the Moon's surface are actually rather dark gray in color. (Some of the upland areas have an albedo of 0.16 or so, whereas the maria and the floors of some craters can have albedos down to 0.06 or so.) For comparison, black paint has an albedo of around 0.05, and aged asphalt has an albedo of about 0.1 - 0.12 (freshly-poured asphalt has an albedo of about 0.04 - 0.05). So, on average, the Moon reflects about as much light as does asphalt; it only looks relatively bright because there's nothing else in the night sky that can reflect or emit anywhere near as much light to us.

By contrast, the Earth has an average albedo of about 0.33, but there's a very wide range. Conifer forests have an albedo of around 0.04 - 0.05, while fresh snow has an albedo of 0.8 - 0.9. (That's comparable to the albedo of a mirror, which is generally 0.72 - 0.85.)

Venus' average albedo is an astonishing 0.76, by the way. It reflects light in the visible part of the spectrum better than do many mirrors. (This is because the surface of Venus is completely obscured by highly reflective clouds.)
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