as·​trom·​e·​try ə-ˈsträ-mə-trē How to pronounce astrometry (audio)
: a branch of astronomy that deals with measurements (as of positions and movements) of celestial bodies
astrometric adjective

Examples of astrometry in a Sentence

Recent Examples on the Web But recently, astronomers were able to combine astrometry and direct imaging together and find an exoplanet. Jackie Appel, Popular Mechanics, 6 May 2023 There’s astrometry, where scientists look for how an exoplanet causes a host star to move in relation to other stars. Jackie Appel, Popular Mechanics, 6 May 2023 But astrometry can reveal planets, too: A planet orbiting a star can cause the star’s position to cyclically shift ever-so-slightly, oscillating back and forth in the plane of the sky. Nola Taylor Tillman, Scientific American, 13 Apr. 2023 Gaia and Hipparcos were both meant to map the Milky Way’s stars (rather than its planets) using a technique called astrometry to precisely track stellar positions, distances and motions. Nola Taylor Tillman, Scientific American, 13 Apr. 2023 To map these stars, astronomers use astrometry — measuring the precise positions of stars. Liz Kruesi, Discover Magazine, 23 Sep. 2016 Everyone was convinced the job was going to be done with astrometry. Andrew Grant, Discover Magazine, 27 Nov. 2012 Most of them were interested in trying to find planets through astrometry, measuring the change in the position of stars due to the pull of their planets’ gravity. Andrew Grant, Discover Magazine, 27 Nov. 2012 Rather than just seeing them as a point of light, its astrometry —precise measurements of the positions and movements—adds data on its size, shape, rotation and surface light scattering properties. Jamie Carter, Forbes, 25 June 2022 See More

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

Word History


astro- + -metry

First Known Use

1811, in the meaning defined above

Time Traveler
The first known use of astrometry was in 1811

Dictionary Entries Near astrometry

Cite this Entry

“Astrometry.” Dictionary, Merriam-Webster, Accessed 1 Dec. 2023.

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