NIST Time Scale Data Archive Updated monthly

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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 ns)
2002-12-26	52634	6 ns
2002-12-19	52627	4 ns
2002-12-12	52620	4 ns
2002-12-05	52613	5 ns
2002-11-28	52606	-4 ns
2002-11-21	52599	3 ns
2002-11-14	52592	4 ns
2002-11-07	52585	2 ns
2002-10-31	52578	6 ns
2002-10-24	52571	6 ns
2002-10-17	52564	6 ns
2002-10-10	52557	6 ns
2002-10-03	52550	5 ns
2002-09-26	52543	5 ns
2002-09-19	52536	5 ns
2002-09-12	52529	0 ns
2002-09-05	52522	-5 ns
2002-08-29	52515	-2 ns
2002-08-22	52508	-6 ns
2002-08-15	52501	-8 ns
2002-08-08	52494	-9 ns
2002-08-01	52487	-5 ns
2002-07-25	52480	-5 ns
2002-07-18	52473	-4 ns
2002-07-11	52466	-2 ns
2002-07-04	52459	0 ns
2002-06-27	52452	2 ns
2002-06-20	52445	6 ns
2002-06-13	52438	10 ns
2002-06-06	52431	11 ns
2002-05-30	52424	-13 ns
2002-05-23	52417	-14 ns
2002-05-16	52410	-13 ns
2002-05-09	52403	-5 ns
2002-05-02	52396	-8 ns
2002-04-25	52389	-12 ns
2002-04-18	52382	-14 ns
2002-04-11	52375	-17 ns
2002-04-04	52368	-15 ns
2002-03-28	52361	-23 ns
2002-03-21	52354	-21 ns
2002-03-14	52347	-25 ns
2002-03-07	52340	-17 ns
2002-02-28	52333	-18 ns
2002-02-21	52326	-19 ns
2002-02-14	52319	-27 ns
2002-02-07	52312	-28 ns
2002-01-31	52305	-25 ns
2002-01-24	52298	-26 ns
2002-01-17	52291	-26 ns
2002-01-10	52284	-20 ns
2002-01-03	52277	-12 ns