par·​sec ˈpär-ˌsek How to pronounce parsec (audio)
: a unit of measure for interstellar space that is equal to 3.26 light-years and is the distance to an object having a parallax of one second as seen from points separated by one astronomical unit

Examples of parsec in a Sentence

Recent Examples on the Web To wrap your mind around that distance, 1 parsec is equal to 3.26 light years or about 206,265 times the distance from Earth to the Sun. Justin Ray, Robb Report, 14 June 2023 The surface of a planet within one parsec of the Milky Way’s center could reach over 5,700 kelvin, as hot as the sun’s surface, just from dark matter traffic. Max G. Levy, Wired, 3 May 2021 The clustered filaments are especially compelling as they are regularly spaced from each other, with roughly one parsec between them. Joshua Rapp Learn, Discover Magazine, 13 May 2022 What, then, can astronomers do to determine whether the final parsec problem is really a problem? Alison Klesman, Discover Magazine, 12 July 2019 This is a huge region; for comparison, ten kiloparsec is about the radius of a typical spiral galaxy like our own Milky Way, and a parsec itself is already pretty big, at more than three light-years. Stephon Alexander, Wired, 31 Aug. 2021 Recently astronomers settled on a value of 25 parsecs (82 light-years) above the plane, but our results strongly disagree with this estimate. Mark J. Reid, Scientific American, 17 Mar. 2020 The problem comes in the final parsec, where gravity is not strong enough to overcome the centrifugal force of each black hole’s orbit to pull the pair closer together. Nola Taylor Redd, Scientific American, 10 Feb. 2020 In this new version, Greedo pulls the trigger first in a wild shot, missing Han by half a parsec. Alex Horton, Washington Post, 13 Nov. 2019 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'parsec.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


parallax + second

First Known Use

1913, in the meaning defined above

Time Traveler
The first known use of parsec was in 1913

Dictionary Entries Near parsec

Cite this Entry

“Parsec.” Dictionary, Merriam-Webster, Accessed 24 Sep. 2023.

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