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NIST USNO 2008 Archive

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)

2008-12-25   54825 12 ns
2008-12-18   54818 11 ns
2008-12-11   54811 9 ns
2008-12-04   54704 5 ns
2008-11-27   54797 1 ns
2008-11-20   54790 -1 ns
2008-11-13   54783 -3 ns
2008-11-06   54776 -5 ns
2008-10-30   54769 -10 ns
2008-10-23   54762 -11 ns
2008-10-16   54755 -11 ns
2008-10-09   54748 -12 ns
2008-10-02   54741 -12 ns
2008-09-25   54734 -11 ns
2008-09-16   54727 -10 ns
2008-09-11   54720 -8 ns
2008-09-04   54713 -5 ns
2008-08-28   54706 -2 ns
2008-08-21   54699 3 ns
2008-08-14   54692 5 ns
2008-08-07   54685 5 ns
2008-07-31   54678 6 ns
2008-07-24   54671 3 ns
2008-07-17   54664 2 ns
2008-07-10   54657 2 ns
2008-07-03   54650 0 ns
2008-06-26   54643 -3 ns
2008-06-19   54636 -7 ns
2008-06-12   54629 -7 ns
2008-06-05   54622 -8 ns
2008-05-29   54615 -10 ns
2008-05-22   54608 -12 ns
2008-05-15   54601 -14 ns
2008-05-08   54594 -14 ns
2008-05-01   54587 -13 ns
2008-04-24   54580 -13 ns
2008-04-17   54573 -15 ns
2008-04-10   54566 -14 ns
2008-04-03   54559 -13 ns
2008-03-27   54552 -14 ns
2008-03-20   54545 -12 ns
2008-03-13   54538 -11 ns
2008-03-06   54531 -9 ns
2008-02-28   54524 -8 ns
2008-02-21   54517 -5 ns
2008-02-14   54510 -3 ns
2008-02-07   54503 -2 ns
2008-01-31   54496 -1 ns
2008-01-24   54489 0 ns
2008-01-17   54482 1 ns
2008-01-10   54475 2 ns
2008-01-03   54468 2 ns
Created January 13, 2010, Updated October 7, 2020