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NIST USNO

UTC (USNO) - UTC (NIST)

The United States Naval Observatory (USNO) and the National Institute of Standards and Technology (NIST) make regular comparisons of their respective time scales. These comparisons are made using GPS common-view measurements from up to approximately 10 GPS satellites. The table below lists recent differences between the two time scales.

Weekly UTC(USNO, Master Clock) - UTC(NIST)Values

 

Date MJD UTC(USNO) - UTC(NIST) (+/- 20 nanoseconds)
2019-10-31 58787 -1.6 ns
2019-10-24 58780 -3.4 ns
2019-10-17 58773 -2.8 ns
2019-10-10 58766 -6.3 ns
2019-10-03 58759 -4.1 ns
2019-09-26 58752 -4.4 ns
2019-09-19 58745 -4.8 ns
2019-09-12 58738 -4.2 ns
2019-09-05 58731 -3.9 ns
2019-08-29 58724 -4.7 ns
2019-08-22 58717 -5.5 ns
2019-08-15 58710 -4.3 ns
2019-08-08 58703 -5.7 ns
2019-08-01 58696 -4 ns
2019-07-25 58689 -2.5 ns
2019-07-18 58682 -0.4 ns
2019-07-11 58675 -0.9 ns
2019-07-04 58668 -1.4 ns
2019-06-27 58661 -4 ns
2019-06-20 58654 -5.8 ns
2019-06-13 58647 -7.6 ns
2019-06-06 58640 -7.4 ns
2019-05-30 58633 -6.9 ns
2019-05-23 58626 -8.4 ns
2019-05-16 58619 -7.8 ns
2019-05-09 58612 -7.9 ns
2019-05-02 58605 -4.9 ns
2019-04-25 58598 -2.7 ns
2019-04-18 58591 -2.2 ns
2019-04-11 58584 -3.1 ns
2019-04-04 58577 -3 ns
2019-03-28 58570 -4.2 ns
2019-03-21 58563 -3.4 ns
2019-03-14 58556 -3.9 ns
2019-03-07 58549 -2 ns
2019-02-28 58542 -4.3 ns
2019-02-21 58535 -6.4 ns
2019-02-14 58528 -8.1 ns
2019-02-07 58521 -6.6 ns
2019-01-31 58514 -3.6 ns
2019-01-24 58507 -4.4 ns
2019-01-17 58500 -5.3 ns
2019-01-10 58493 -5.9 ns
2019-01-03 58486 -4.1 ns
Created September 18, 2009, Updated December 2, 2019