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NIST USNO 2007 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)

2007-12-27   54461 4 ns
2007-12-20   54454 5 ns
2007-12-13   54447 5 ns
2007-12-06   54440 6 ns
2007-11-29   54433 7 ns
2007-11-22   54426 8 ns
2007-11-15   54419 7 ns
2007-11-08   54412 7 ns
2007-11-01   54405 7 ns
2007-10-25     54398 8 ns
2007-10-18   54391 7 ns
2007-10-11   54384 6 ns
2007-10-04   54377 4 ns
2007-09-27   54370 2 ns
2007-09-20   54363 0 ns
2007-09-13   54356 -1 ns
2007-09-06   54349 -3 ns
2007-08-30   54342 -4 ns
2007-08-23   54335 -4 ns
2007-08-16   54328 -4 ns
2007-08-09   54321 -2 ns
2007-08-02   54314 -4 ns
2007-07-26   54307 -3 ns
2007-07-19   54300 -3 ns
2007-07-12   54293 -2 ns
2007-07-05   54286 -1 ns
2007-06-28   54279 1 ns
2007-06-21   54272 3 ns
2007-06-14   54265 4 ns
2007-06-07   54258 4 ns
2007-05-31   54251 6 ns
2007-05-24   54244 9 ns
2007-05-17   54237 11 ns
2007-05-10   54230 12 ns
2007-05-03   54223 15 ns
2007-04-26   54216 15 ns
2007-04-19   54209 16 ns
2007-04-12   54202 15 ns
2007-04-05   54195 16 ns
2007-03-29   54188 19 ns
2007-03-22   54181 20 ns
2007-03-15   54174 21 ns
2007-03-08   54167 21 ns
2007-03-01   54160 21 ns
2007-02-22   54153 23 ns
2007-02-15   54146 23 ns
2007-02-08   54139 23 ns
2007-02-01   54132 25 ns
2007-01-25   54125 26 ns
2007-01-18   54118 28 ns
2007-01-11   54111 28 ns
2007-01-04   54104 26 ns
Created January 13, 2010, Updated October 7, 2020