[IGSREPORT-3974] Wk 0915 GPS Earth Orientation

[Dennis]

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IGS Electronic Report    Thu Jul 24 11:58:36 PDT 1997      Message Number 3974
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Author: Dennis McCarthy
Subject: Wk 0915 GPS Earth Orientation

From: Dennis McCarthy
Subject: Earth Orientation Contributions to IERS Bulletin A
Date: 24 Jul 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.    50648.88    22               -.019                .035

NEOS VLBI    50645.25     5   -.10  -.10   .005    .06   .08   .007

JPL VLBI     50649.76     7                .023                .034

CSR SLR      50649.11    10   -.24   .40  -.003    .30   .25   .072

TUD SLR      50589.00    10    .17   .09           .39   .34

UT LLR       50627.17    10               -.006                .078

IGS Final    50641.50    30    .06  -.02           .08   .07

IGS Rapid    50651.50    10    .03  -.08           .13   .14

             50651.50     3                .096                .107

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           50641.5    30   -.13  -.25           .14   .16

CODE          50648.5    30   -.32   .07 -17.82    .12   .20    .12

JPL           50641.5    30   -.21  -.19  -2.73    .12   .11    .65

ESOC          50641.5    30   -.08  -.21           .19   .14

NRCan         50648.5    30   -.40  -.50  10.83    .21   .20    .04

GFZ           50641.5    30   -.19  -.31    .03    .16   .12    .08

NOAA          50648.5    30   -.66  -.34           .29   .38

USNO          50647.5    30   -.50  -.54           .21   .25

IGS Final     50641.5    30   -.24  -.20    .00    .07   .07    .01

IGS Rapid     50651.5    30   -.29  -.26   -.06    .16   .18    .12

IERS Central Bureau Series:

Bulletin B    50604.     30   -.04   .01   .000    .12   .13   .034

97C04         50650.     30   -.05   .09  -.037    .19   .22   .094


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>]