What was the rotational velocity of Earth on Dec 31, 1899

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The discussion focuses on calculating the Earth's rotational velocity on December 31, 1899, which is significant because time is defined in relation to this date. The calculation involves dividing the length of the day by the Earth's rotation, revealing that the Earth rotated 360.9856 degrees in 24 hours. This results in a rotational velocity of approximately 0.004178 degrees per second or 15.041 degrees per hour. The conversation highlights the importance of precise measurements in timekeeping and Earth's rotation. Understanding these calculations is essential for accurate time definitions and standards.
Patrick Aberdeen
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I ask because time is defined with reference to this day (the SI second is based on a caesium clock is calibrated with reference to the 1952 ephemeris time standard, which was based on a second being 1/86 400th of Jan 0, 1900 (with Jan 0 being Dec 31 of 1899).

So... how do I calculate the rotational velocity of Earth on that day?
 
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Divide the length of the day by how far Earth rotated.

(hint: it isn't 360 degrees)
 
Right- of course! that's embarrassing :-p - thanks!

360.9856° / 86400 s = 0.004178°/s or 15.041°/hr

Thank you Russ
 
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