Author: IERS Rapid Service/Prediction Center Subject: Earth Orientation Contributions to IERS Bulletin A Date: 14 Feb 19 In this report, individual Earth orientation time series are compared to the IERS Bulletin A combination. For further information, including the raw time series, refer to http://www.usno.navy.mil/USNO/earth-orientation/ eo-info/general. The first table below shows some comparison results for those series included in Bulletin A during the last 30 days. All data are aligned to the system defined the ITRF and the ICRF reference frames by removing a priori mean bias and rate. Units: milliseconds of arc for x, y; milliseconds of time for UT1-UTC Contributor Latest # Mean Standard Deviation Series Day (series-BullA) x y UT1-UTC x y UT1-UTC GSI Int. 58524.33 10 0.005 0.015 GSFC Int. 58525.31 32 -0.006 0.013 USNO Int. 58525.31 32 0.007 0.013 IAA VLBI 58442.21 3 -0.07 -0.39 -0.003 0.10 0.07 0.005 GSFC VLBI 58515.27 10 -0.04 -0.04 0.002 0.07 0.08 0.001 USNO VLBI 58515.27 9 -0.10 0.00 -0.004 0.10 0.06 0.005 IVS VLBI 58480.27 8 -0.08 -0.06 0.003 0.06 0.09 0.003 ILRS SLR 58519.50 12 -0.06 0.00 0.09 0.10 IAA SLR 58463.81 30 0.02 0.18 0.16 0.15 MCC SLR 58460.00 29 0.08 0.25 0.09 0.14 IGS Final 58509.50 30 0.00 0.00 0.02 0.02 IGS Rapid 58527.50 18 0.00 0.00 0.03 0.03 --- --- --- --- IGS Ultra 58528.00 2 -0.01 -0.01 0.04 0.02 58528.00 11 -0.001* 0.006* USNO GPS 58528.25 32 -0.013* 0.038* NCEP AAM 58535.50 15 0.000 0.001 * All satellite techniques provide information on the rate of change of Universal Time contaminated by effects due to unmodelled orbit node motion. VLBI-based results have been used to minimize drifts in UT estimates. The following table shows comparisons for other related time series during the last 30 days. No systematic corrections have been applied. Units: milliseconds of arc for x, y; milliseconds of time for UT, LOD Latest # Mean Standard Deviation Series Day (series-BullA) x y UT LOD x y UT LOD IGS Final 58509.5 30 0.00 0.00 -0.001*-0.001* 0.03 0.03 0.013* 0.016* IGS Rapid 58526.5 30 -0.01 -0.01 -0.007* 0.000* 0.04 0.04 0.040* 0.016* IGS Ultra 58527.25 120 -0.03 -0.02 -0.006* 0.003* 0.04 0.04 0.051* 0.035* Bulletin B 58484.0 30 -0.05 0.01 -0.040 0.05 0.04 0.021 14C04 58483.0 30 -0.04 0.01 -0.042 0.06 0.03 0.021 Plots of the residuals are available at http://www.usno.navy.mil/USNO/ earth-orientation/eo-products/weekly. ------------------------------------------------------------------------------ The IERS Rapid Service/Prediction Center is an activity of the Earth Orientation Department at the U.S. Naval Observatory.