exo·​plan·​et | \ ˈek-sō-ˌpla-nət How to pronounce exoplanet (audio) , ˌek-sō-ˈpla-\

Definition of exoplanet

: a planet orbiting a star that is not our sun

Examples of exoplanet in a Sentence

Recent Examples on the Web

Hubble’s latest observations: exoplanets, astrophysical jets and the bubble nebula. Mark Dawidziak, cleveland.com, "Apollo 11 anniversary fuels two-week run of space programming," 5 July 2019 Many telescopes, in space and on the ground, are staring at the heavens in search of exoplanets silhouetted against the bright faces of their stars. Simon J. Lock, Scientific American, "When Earth and the Moon Were One," 2 July 2019 Their giant mirrors will gather enough light to probe the atmospheres of nearby exoplanets and detect the first galaxies forming in the early universe. Daniel Clery, Science | AAAS, "Divisive giant telescope cleared for construction on Hawaiian peak," 25 June 2019 Hundreds of exoplanets have been discovered since then, often using natural star-blocking techniques. David Grossman, Popular Mechanics, "NASA Wants to Block Out Distant Stars with the Craziest Flying Formation Ever," 14 June 2019 A few years later, astronomers discovered two worlds orbiting another star, a pulsar named PSR 1257+12, and that was that — the era of uncertainty was over and the first exoplanets had been found, destined for the history books. Nola Taylor Redd, Discover Magazine, "The Fight Over Who Really Found the First Exoplanet," 16 May 2019 And since astronomers have discovered many Neptune and Uranus-sized exoplanets, the findings could be applicable to far-flung parts of the cosmos. National Geographic, "Bizarre form of hot ice seen on Earth," 8 May 2019 Among other things, the Webb telescope is designed to scour the atmospheres of exoplanets to look for chemical signatures of oxygen, carbon dioxide, or methane — which could suggest the presence of life. Denise Chow /, NBC News, "NASA's new satellite will scan the cosmos for alien worlds," 13 Apr. 2018 The list of exomoons is significantly smaller than the list of exoplanets. Fox News, "Exomoons could be home to extraterrestrial life, researcher says," 6 June 2019

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

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First Known Use of exoplanet

1992, in the meaning defined above

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Statistics for exoplanet

Last Updated

9 Jul 2019

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Time Traveler for exoplanet

The first known use of exoplanet was in 1992

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More from Merriam-Webster on exoplanet

Britannica English: Translation of exoplanet for Arabic Speakers

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characterized by aphorism

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