as·​trom·​e·​try | \ ə-ˈsträ-mə-trē How to pronounce astrometry (audio) \

Definition of astrometry

: a branch of astronomy that deals with measurements (as of positions and movements) of celestial bodies

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Other Words from astrometry

astrometric \ ˌa-​strə-​ˈme-​trik How to pronounce astrometric (audio) \ adjective

Examples of astrometry in a Sentence

Recent Examples on the Web More tantalizing support emerged in 2018 from the European Space Agency’s Milky Way–mapping Gaia satellite, which uses a technique called astrometry to precisely track the position of Proxima Centauri—and billions of other stars—across the sky. Lee Billings, Scientific American, "The Curious Case of Proxima C," 15 Jan. 2020 Breakthrough Watch is also pursuing a separate mission called TOLIBOY, tentatively set for a 2021 launch, which would search for planets by precisely mapping the motions of Alpha Centauri A and B using a technique called astrometry. Corey S. Powell, Scientific American, "The Hunt Is on for Alpha Centauri’s Planets," 5 Aug. 2019 Byrd explains that Gaia studies the motions of individual stars using a technique called astrometry. Jason Daley, Smithsonian, "2.8 Million Stars Sparkle in This Incredible Image of the Milky Way," 6 Sep. 2017 Measuring these shifts, or parallaxes, lets astronomers calculate the stars’ actual positions and movements through the galaxy with great precision, a field of study called astrometry that Gaia and its predecessor Hipparcos have revitalized. Michael Greshko, National Geographic, "New Milky Way Map Is a Spectacular Billion-Star Atlas," 14 Sep. 2016

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'astrometry.' 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 astrometry

1811, in the meaning defined above

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Time Traveler for astrometry

Time Traveler

The first known use of astrometry was in 1811

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Cite this Entry

“Astrometry.” Dictionary, Merriam-Webster, Accessed 7 Aug. 2020.

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