event horizon

noun

Definition of event horizon

: the surface of a black hole : the boundary of a black hole beyond which nothing can escape from within it

Examples of event horizon in a Sentence

Recent Examples on the Web Sahu says that if this solar mass black hole is 7.1 times the mass of our Sun, its event horizon (or its outer boundary) would be about 26 miles in diameter. Bruce Dorminey, Forbes, 11 June 2022 Its event horizon is nearly 25 billion miles wide, with a mass roughly that of 6.5 billion suns. Corinne Purtillstaff Writer, Los Angeles Times, 12 May 2022 In contrast, the accretion disk around a feeding black hole is viscous and hot, and its temperature increases from its exterior toward the event horizon of the black hole. Aaron S. Evans, Scientific American, 1 Dec. 2021 And then the gravitational interaction with local light gets concentrated in this ring that’s two-and-a-half times bigger that the event horizon. Corinne Purtillstaff Writer, Los Angeles Times, 13 May 2022 The black hole has no finite size, but there is this abstract size of the event horizon, which is the last point that light can escape. Corinne Purtillstaff Writer, Los Angeles Times, 13 May 2022 The 2019 result showed that the shadow of an event horizon is, as predicted, spherical. Marina Koren, The Atlantic, 12 May 2022 Even reasonable predictions on a twenty-year event horizon are seen as fussy impediments to construction. Emily Witt, The New Yorker, 3 May 2022 Telescopes in the millimetre-wavelength range can image the event horizon of a black hole, says project manager Marc Klein Wolt, who is also managing director of the Radboud Radio Lab at Radboud University. Sarah Wild, Scientific American, 9 Feb. 2022 See More

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

First Known Use of event horizon

1956, in the meaning defined above

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Time Traveler for event horizon

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The first known use of event horizon was in 1956

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Dictionary Entries Near event horizon

even the score

event horizon

even though

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Last Updated

19 Jun 2022

Cite this Entry

“Event horizon.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/event%20horizon. Accessed 13 Aug. 2022.

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