Author: IERS Rapid Service/Prediction Center
Subject: Earth Orientation Contributions to IERS Bulletin A
Date: 26 Feb 15


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.     57075.33    10              -0.004               0.013

GSFC Int.    57075.33    32              -0.003               0.013

USNO Int.    57073.80    20               0.001               0.012

IAA VLBI     57056.21     9  -0.52 -0.19 -0.002   0.26  0.18  0.019

GSFC VLBI    57056.21    10   0.04  0.03  0.000   0.09  0.06  0.004

USNO VLBI    57056.21     9   0.03  0.02  0.005   0.10  0.13  0.007

IVS  VLBI    57056.21     6  -0.11 -0.21 -0.006   0.13  0.10  0.006

ILRS SLR     57077.50    30  -0.22 -0.01          0.21  0.13

IAA SLR      57063.53    31   0.06 -0.05          0.17  0.16

MCC SLR      57067.00    27   0.16  0.30          0.15  0.13

IGS Final    57067.50    30   0.00  0.00          0.01  0.01

IGS Rapid    57078.50    11   0.00  0.01          0.01  0.04

             ---        ---               ---                 ---

IGS Ultra    57079.00     2   0.01 -0.02          0.02  0.01

             57079.00    15               0.004*              0.008*

USNO GPS     57079.25    32               0.004*              0.018*

NCEP AAM     57086.50    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    57067.5  30   0.00  0.02  0.000*-0.003*  0.03  0.03  0.006* 0.012*

IGS Rapid    57077.5  30   0.00  0.01 -0.004* 0.003*  0.03  0.04  0.027* 0.015*

IGS Ultra    57078.25 120 -0.01  0.00 -0.003* 0.005*  0.04  0.04  0.039* 0.033*

Bulletin B   57023.0  30   0.01  0.01  0.001          0.02  0.04  0.018

08C04        57049.0  30   0.01  0.01  0.006          0.02  0.02  0.016


Plots of the residuals are available at http://www.usno.navy.mil/USNO/
earth-orientation/eo-products/weekly.
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The IERS Rapid Service/Prediction Center is an activity of the Earth
Orientation Department at the U.S. Naval Observatory.