[IGSREPORT-4479] Wk 0939 GPS Earth Orientation

[Dennis]

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IGS Electronic Report    Thu Jan  8 11:00:45 PST 1998      Message Number 4479
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Author: Dennis McCarthy
Subject: Wk 0939 GPS Earth Orientation

From: Dennis McCarthy
Subject: Earth Orientation Contributions to IERS Bulletin A
Date:  8 Jan 98


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.    50816.93    21               -.005                .022

NEOS VLBI    50806.17     5    .07   .04   .001    .10   .05   .003

JPL VLBI     50721.86     8               -.005                .127

CSR SLR      50814.84    10    .28  -.18  -.010    .96   .28   .132

TUD SLR      50814.00     9    .03   .05           .47   .49

IAA SLR      50819.00    30    .02  -.09           .23   .15

IGS Final    50809.50    30    .01   .00           .08   .05

IGS Rapid    50819.50    10   -.12  -.01           .29   .19

             50819.50     3                .037                .039

USNO GPS     50819.50    30                .122                .048

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           50809.5    30   -.59  -.08           .31   .16

CODE          50815.5    30   -.38   .27 -15.24    .07   .12    .05

JPL           50809.5    30   -.08  -.29   4.99    .15   .11    .16

ESOC          50809.5    30   -.12  -.47           .46   .24

NRCan         50816.5    30   -.21  -.80  11.47    .26   .26    .14

GFZ           50809.5    30   -.31   .03   -.01    .17   .17    .07

NOAA          50813.5    30   -.66  -.86           .23   .35

USNO          50813.5    30   -.03  -.61           .21   .27

USNO GPS UT1  50819.5    30                 .12                 .05

IGS Final     50809.5    30   -.29  -.16    .00    .10   .06    .02

IGS Rapid     50819.5    30   -.40  -.33    .00    .30   .26    .08

IERS Central Bureau Series:

Bulletin B    50784.     30   -.07  -.11   .009    .12   .10   .012

97C04         50818.     30   -.11  -.09  -.011    .11   .19   .032


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>]