Author: IERS Rapid Service/Prediction Center
Subject: Earth Orientation Contributions to IERS Bulletin A
Date: 16 May 13


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.     56424.27    14              -0.002               0.014

GSFC Int.    56427.79    27               0.001               0.010

USNO Int.    56427.79    25               0.001               0.011

IAA VLBI     56412.21     9   0.11 -0.08 -0.005   0.14  0.31  0.010

GSFC VLBI    56415.27     9  -0.16  0.17  0.002   0.17  0.20  0.007

USNO VLBI    56412.21     9  -0.30 -0.05  0.004   0.14  0.23  0.007

IVS  VLBI    56412.21     9  -0.06 -0.15  0.000   0.09  0.10  0.005

ILRS SLR     56426.50    29  -0.21  0.24          0.16  0.14

IAA SLR      56426.69    30   0.10  0.04          0.16  0.15

MCC SLR      56423.00    30   0.26  0.22          0.11  0.12

IGS Final    56409.50    30   0.00  0.00          0.01  0.01

IGS Rapid    56427.50    18   0.00  0.00          0.04  0.03

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

IGS Ultra    56428.00     2  -0.03  0.00          0.06  0.04

             56428.00     1               0.001                 ---

USNO GPS     56427.75    32              -0.004*              0.015*

NCEP AAM     56435.50    15              -0.001               0.003

* 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    56409.5  30   0.00  0.02  0.003*-0.003*  0.02  0.02  0.004* 0.010*

IGS Rapid    56426.5  30   0.01  0.00  0.000* 0.001*  0.05  0.03  0.030* 0.014*

IGS Ultra    56427.25 120  0.00  0.02  0.009* 0.003*  0.05  0.04  0.033* 0.035*

Bulletin B   56383.0  30   0.00  0.00  0.001          0.02  0.02  0.008

08C04        56398.0  30   0.00  0.00  0.002          0.02  0.02  0.008


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.