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NIST USNO 2005 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)

2005-12-29   53733 5 ns
2005-12-22   53726 4 ns
2005-12-15   53719 5 ns
2005-12-08   53712 7 ns
2005-12-01   53705 7 ns
2005-11-24   53697 5 ns
2005-11-17   53691 4 ns
2005-11-10   53684 3 ns
2005-11-03   53677 1 ns
2005-10-27   53670 -2 ns
2005-10-20   53663 -4 ns
2005-10-13   53656 -4 ns
2005-10-06   53649 -4 ns
2005-09-29   53642 -4 ns
2005-09-22   53635 -7 ns
2005-09-15   53628 -8 ns
2005-09-08   53621 -9 ns
2005-09-01   53614 -10 ns
2005-08-25   53607 -10 ns
2005-08-18   53600 -10 ns
2005-08-11   53593 -7 ns
2005-08-04   53586 -5 ns
2005-07-28   53579 -2 ns
2005-07-21   53572 1 ns
2005-07-14   53565 4 ns
2005-07-07   53558 7 ns
2005-06-30   53551 7 ns
2005-06-23   53544 9 ns
2005-06-16   53537 9 ns
2005-06-09   53530 7 ns
2005-06-02   53523 7 ns
2005-05-26   53516 4 ns
2005-05-19   53509 3 ns
2005-05-12   53502 4 ns
2005-05-05   53495 1 ns
2005-04-28   53488 1 ns
2005-04-21   53481 2 ns
2005-04-14   53474 0 ns
2005-04-07   53467 -1 ns
2005-03-31   53460 -1 ns
2005-03-24   53453 -3 ns
2005-03-17   53446 -3 ns
2005-03-10   53439 -3 ns
2005-03-03   53432 -2 ns
2005-02-24   53425 -1 ns
2005-02-17   53418 -1 ns
2005-02-10   53411 0 ns
2005-02-03   53404 0 ns
2005-01-27   53397 3 ns
2005-01-20   53390 6 ns
2005-01-13   53383 13 ns
2005-01-06   53376 11 ns
Created January 13, 2010, Updated October 7, 2020