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n. The sunlight reflected from the earth's surface that illuminates part of the moon not directly lighted by the sun. Also called earthlight.

n. Reflected earthlight visible on the Moon's night side.

"An international team has shown that the difference in reflection of light from the Earth's land masses and oceans can be seen on the dark side of the moon, a phenomenon known as earthshine, the 'Astrobiology' journal reported."

albedo   

moonshine