[IGSREPORT-3689] Wk 0902 Earth Orientation

[Dennis]

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IGS Electronic Report    Wed Apr 30  6:47:05 PDT 1997      Message Number 3689
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Author: Dennis McCarthy
Subject: Wk 0902 Earth Orientation

From:     Dennis McCarthy
Subject:  Earth Orientation Contributions to IERS Bulletin A
Date:     25 April 1997


An updated look at Earth orientation data submitted to the IERS
follows.  All data are aligned to the system defined by ITRF94 and
the current ICRF by estimating and removing mean bias and rate terms. 
The only exception to this are the NEOS VLBI and NEOS Intensive
series whose UT1-UTC are not corrected.

Below are the mean and standard deviation of each submission compared
with the Rapid Service for the last 30 days.  Units are milliseconds
of arc for x and y, and milliseconds of time for UT1-UTC.

Contributor   Latest     #         Mean          Standard Deviation
               Day              (NEOS-GPS)
                              x     y   UT1-UTC    x     y  UT1-UTC

NEOS Int.    50557.80   25               0.023               0.031

NEOS VLBI    50554.25    5  -0.04  0.09 -0.008   0.12  0.07  0.008

JPL VLBI     50560.54    8               0.030               0.136

CSR SLR      50552.57   10   0.10  0.00  0.032   0.54  0.20  0.102

TUD SLR      50547      10  -0.17  0.16          0.57  0.19

IAA SLR      50561      30   0.34  0.02          0.46  0.25

UT LLR       50556.86   11              -0.248               0.277

GPS Comb.*   50560.5    30  -0.01 -0.04          0.08  0.11

             50560.5     3               0.054               0.041

     * GPS series is a combination of results from IGS Analysis
     Centers (see below) and USNO.

For comparison, the mean and standard deviations of other related
series are listed below for the last 30 days.  Units are milliseconds
of arc for x and y, and milliseconds of time for UT1-UTC.

Series        Latest     #         Mean          Standard Deviation
               Day              (NEOS-GPS)
                              x     y  UT1-UTC    x     y  UT1-UTC

Scripps      50550.5    30  -0.20 -0.13          0.13  0.14

CODE         50557.5    30  -0.36  0.08 -18.46   0.11  0.13  0.22

JPL          50550.5    30  -0.21 -0.14  -3.64   0.17  0.27  0.14

ESOC         50557.5    30  -0.23 -0.29          0.19  0.27

NRCan        50557.5    30  -0.03 -0.35  10.18   0.23  0.15  0.09

GFZ          50557.5    30  -0.31 -0.23          0.12  0.15

NOAA         50559.5    30  -0.48 -0.33          0.85  0.67

USNO         50560.5    30  -0.30 -0.77          0.30  0.39

IGS Final    50550.5    30  -0.26 -0.16  -0.06   0.09  0.13  0.04

IGS Rapid    50561.5    30  -0.27 -0.08  -0.08   0.23  0.28  0.20


IERS Central Bureau Series:

Bulletin B   50509      30  -0.01  0.06 -0.029   0.09  0.14  0.030

97c04        50560      30  -0.01  0.00 -0.019   0.13  0.13  0.028


Plots of the residuals are available by FAX or through the world wide
web at http://maia.usno.navy.mil/plots.html to anyone interested.     
--
Dennis D. McCarthy                       dmc at maia.usno.navy.mil
Director, Directorate of Time            phone: (202) 762-1837
U.S. Naval Observatory                   fax: (202) 762-1563
Washington, DC 20392-5420


[Mailed From: Dennis McCarthy <dmc at Maia.usno.navy.mil>]