[IGSREPORT-4371] Wk 0933 GPS Earth Orientation

[Dennis]

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IGS Electronic Report    Mon Dec  1  7:21:21 PST 1997      Message Number 4371
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Author: Dennis McCarthy
Subject: Wk 0933 GPS Earth Orientation

From: Dennis McCarthy
Subject: Earth Orientation Contributions to IERS Bulletin A
Date: 26 Nov 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.    50774.87    20                .018                .027

NEOS VLBI    50771.25     5    .02  -.02  -.002    .04   .03   .005

JPL VLBI     50721.86     8               -.010                .132

CSR SLR      50775.06    10   -.25  -.05  -.032    .24   .19   .115

IGS Final    50767.50    30    .07   .01           .10   .08

IGS Rapid    50776.50     9    .00   .04           .09   .11

             50776.50     2                .013                .014

USNO GPS     50776.50    27                .071                .050

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           50767.5    30   -.40  -.08           .17   .17

CODE          50772.5    30   -.47   .27 -15.85    .13   .15    .17

JPL           50767.5    30   -.02  -.19   3.73    .14   .16    .36

ESOC          50767.5    30   -.04  -.35           .17   .18

NRCan         50767.5    30    .04  -.42  11.10    .13   .19    .05

GFZ           50767.5    30   -.20  -.34    .09    .14   .20    .17

NOAA          50775.5    30   -.47  -.40           .37   .39

USNO          50770.5    30    .01  -.49           .21   .34

USNO GPS UT1  50776.5    27                 .07                 .05

IGS Final     50767.5    30   -.22  -.15    .04    .10   .09    .04

IGS Rapid     50776.5    30   -.35  -.33    .11    .21   .19    .16

IERS Central Bureau Series:

Bulletin B    50724.     30   -.02  -.02   .007    .08   .15   .016

97C04         50778.     30   -.11  -.17   .008    .33   .30   .064


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>]