[IGSREPORT-4385] Wk 0934 GPS Earth Orientation

[Dennis]

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IGS Electronic Report    Thu Dec  4  8:07:43 PST 1997      Message Number 4385
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Author: Dennis McCarthy
Subject: Wk 0934 GPS Earth Orientation

From: Dennis McCarthy
Subject: Earth Orientation Contributions to IERS Bulletin A
Date:  4 Dec 97


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, rate, annual
and semiannual terms.  The only exception to this is the NEOS VLBI
and the NEOS Intensives series whose UT1-UTC are not corrected.

Below are the mean and standard deviation of each submission
included in the Rapid Service combination compared with the
combination 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-series)
                                x     y  UT1-UTC    x     y  UT1-UTC

NEOS Int.    50783.69    22                .018                .028

NEOS VLBI    50778.25     5    .02   .00  -.003    .02   .01   .002

JPL VLBI     50721.86     8               -.009                .132

CSR SLR      50783.47    11   -.29   .21  -.104    .34   .69   .165

IGS Final    50774.50    30    .07   .03           .09   .09

IGS Rapid    50784.50    10    .00  -.04           .08   .08

             50784.50     1                .041                 ---

USNO GPS     50784.50    29                .106                .070

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-series)
                                x     y  UT1-UTC    x     y  UT1-UTC

SIO           50774.5    30   -.46  -.14           .14   .17

CODE          50781.5    30   -.42   .28 -15.67    .16   .17    .18

JPL           50774.5    30   -.04  -.17   3.97    .15   .16    .26

ESOC          50774.5    30    .01  -.29           .20   .22

NRCan         50779.5    30    .05  -.44  11.07    .16   .24    .06

GFZ           50774.5    30   -.21  -.27    .11    .15   .21    .15

NOAA          50783.5    30   -.72  -.49          1.38   .43

USNO          50780.5    30    .08  -.54           .20   .34

USNO GPS UT1  50784.5    29                 .11                 .07

IGS Final     50774.5    30   -.22  -.14    .03    .10   .10    .04

IGS Rapid     50784.5    30   -.35  -.30    .11    .17   .17    .15

IERS Central Bureau Series:

Bulletin B    50754.     30    .00  -.04   .005    .09   .14   .031

97C04         50786.     30    .14  -.07   .031    .54   .22   .067


Plots of the residuals are available 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>]