astronomical unit

noun

: a unit of length used in astronomy equal to the mean distance of the earth from the sun or about 93 million miles (150 million kilometers)

Examples of astronomical unit in a Sentence

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Graph: Rhett Allain Here, position is measured in astronomical units (AU), which was originally defined as the average distance from the sun to Earth. Rhett Allain, WIRED, 22 Nov. 2024 Calculations found that the outer star is 3,500 astronomical units (AU) away from the black hole. Laura Baisas, Popular Science, 23 Oct. 2024 The numbers on the graph depict AUs, or astronomical units. James Wray, Discover Magazine, 18 Oct. 2024 The Solar Orbiter ventures between 1 astronomical unit, where the Earth is, and 0.3 astronomical units, a little closer to the Sun than Mercury. Yeimy J. Rivera, Discover Magazine, 6 Sep. 2024 See all Example Sentences for astronomical unit 

Word History

First Known Use

1848, in the meaning defined above

Time Traveler
The first known use of astronomical unit was in 1848

Dictionary Entries Near astronomical unit

Cite this Entry

“Astronomical unit.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/astronomical%20unit. Accessed 30 Dec. 2024.

Kids Definition

astronomical unit

noun
: a unit of length used in astronomy equal to the average distance of the earth from the sun or about 93 million miles (150 million kilometers)

More from Merriam-Webster on astronomical unit

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