proper motion

noun

: the apparent change in position of a star usually expressed in seconds of arc per year that results from the projection on the celestial sphere of its motion with respect to the solar system see tangential motion

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Dictionary Entries Near proper motion

properly

proper motion

proper noun

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“Proper motion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/proper%20motion. Accessed 26 Nov. 2024.

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