earth·​shine | \ ˈərth-ˌshīn How to pronounce earthshine (audio) \

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 Their results were in line with earthshine fluctuations measured by the CERES satellite, which is part of the NASA's Earth Observing System (EOS). Jamie Carter, Forbes, 6 Dec. 2021 Measured from the Big Bear Solar Observatory in California between 1998 and 2017, the researchers monitored the precise daily, monthly, seasonal, yearly and decadal changes in Earth’s albedo using earthshine. Jamie Carter, Forbes, 6 Dec. 2021 The amount of earthshine will vary from night to night and season to season. Jennifer Gray, CNN, 4 Oct. 2021 In a shocking turn of events, the last three years of their study showed the earthshine had gone down dramatically. Jennifer Gray, CNN, 4 Oct. 2021 The conclusion came from a group of researchers that studied two decades' worth of data on earthshine, or the light reflected off Earth that illuminates the moon. Jordan Mendoza, USA TODAY, 4 Oct. 2021 On the moon, that means from bright sunshine to dim earthshine. Popular Mechanics Editors, Popular Mechanics, 20 July 2019 This effect is caused by earthshine — the light of the sun shines on the Earth and reflects upon the moon. Dean Regas, USA TODAY, 23 Oct. 2017 See More

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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Cite this Entry

“Earthshine.” Dictionary, Merriam-Webster, Accessed 19 May. 2022.

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