absolute magnitude

noun

: a measure of the intrinsic luminosity of a celestial body (such as a star) expressed as the apparent magnitude the body would have if viewed from a distance of 10 parsecs

Examples of absolute magnitude in a Sentence

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However, based on its absolute magnitude of 26.14, estimates suggest the asteroid measures between 50 and 115 feet (15-35 meters) across, depending on how reflective its surface is. Jamie Carter, Forbes.com, 13 May 2026

Word History

First Known Use

1885, in the meaning defined above

Time Traveler
The first known use of absolute magnitude was in 1885

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Cite this Entry

“Absolute magnitude.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/absolute%20magnitude. Accessed 4 Jun. 2026.

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