earth·​shine | \ˈərth-ˌshīn \

Definition of earthshine 

: sunlight reflected by the earth that illuminates the dark part of the moon Because the moon will be near half phase, earthshine will brighten the dark portion of the moon.Astronomy

called also earthlight

Examples of earthshine in a Sentence

Recent Examples on the Web

This effect is caused by earthshine — the light of the sun shines on the Earth and reflects upon the moon. Dean Regas, USA TODAY, "Lunar secrets: Why doesn’t the moon have a better name?," 23 Oct. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'earthshine.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of earthshine

1834, in the meaning defined above

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The first known use of earthshine was in 1834

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