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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The amount of movement on the sky would be tiny — about three arcminutes per year at a distance of approximately 700 astronomical units (AU).
—
Keith Cooper, Space.com, 1 May 2025
The team discovered many young stars hosting tiny protoplanetary disks, some not much thicker than the distance between Earth and the sun (an astronomical unit, or AU).
—Robert Lea, Space.com, 28 Mar. 2025
Creating Comets The Oort cloud spans a great distance, from around 2,000 to between 100,000 and 200,000 astronomical units (au).
—Jack Knudson, Discover Magazine, 24 Feb. 2025
The inner edge of the Oort Cloud is believed to be between 2,000 and 5,000 astronomical units (AU) from the sun—with one AU equal to around 93 million miles.
—Dan Perry, Newsweek, 28 Feb. 2025
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Keith Cooper, Space.com, 1 May 2025
The team discovered many young stars hosting tiny protoplanetary disks, some not much thicker than the distance between Earth and the sun (an astronomical unit, or AU).
—Robert Lea, Space.com, 28 Mar. 2025
Creating Comets The Oort cloud spans a great distance, from around 2,000 to between 100,000 and 200,000 astronomical units (au).
—Jack Knudson, Discover Magazine, 24 Feb. 2025
The inner edge of the Oort Cloud is believed to be between 2,000 and 5,000 astronomical units (AU) from the sun—with one AU equal to around 93 million miles.
—Dan Perry, Newsweek, 28 Feb. 2025
See All Example Sentences for astronomical unit
Cite this Entry
“Astronomical unit.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/astronomical%20unit. Accessed 10 Jun. 2025.
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