apparent magnitude


Definition of apparent magnitude

: the luminosity of a celestial body (such as a star) as observed from the earth — compare absolute magnitude

Examples of apparent magnitude in a Sentence

Recent Examples on the Web The fifth brightest star in the night sky and about 25 light-years away, this blue star is a yardstick for judging the apparent magnitude, or brightness, of stars. Jamie Carter, Forbes, 5 June 2022 Vega is how the apparent magnitude of stars—their brightness—is measured. Jamie Carter, Forbes, 31 May 2021 For example, Neptune has an apparent magnitude of about 7.7. Jackie Wattles, CNN, 2 July 2020 The dimmest stars humans can see with the naked eye have an apparent magnitude (intrinsic magnitude modified by distance) of about 6 (lower numbers are brighter). Jay Bennett, Popular Mechanics, 26 Mar. 2018

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

First Known Use of apparent magnitude

1708, in the meaning defined above

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Time Traveler for apparent magnitude

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The first known use of apparent magnitude was in 1708

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Dictionary Entries Near apparent magnitude


apparent magnitude

apparent noon

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Cite this Entry

“Apparent magnitude.” Dictionary, Merriam-Webster, Accessed 3 Oct. 2022.

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