sidereal time


Definition of sidereal time

1 : time based on the sidereal day
2 : the hour angle of the vernal equinox at a place

Examples of sidereal time in a Sentence

Recent Examples on the Web The sky chart is a disk that rotates at a speed of sidereal time (23 hours, 56 minutes and 4 seconds). Roberta Naas, Forbes, 7 Apr. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'sidereal time.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of sidereal time

1765, in the meaning defined at sense 1

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The first known use of sidereal time was in 1765

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Dictionary Entries Near sidereal time

sidereal second

sidereal time

sidereal year

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Statistics for sidereal time

Cite this Entry

“Sidereal time.” Dictionary, Merriam-Webster, Accessed 25 Oct. 2021.

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