[IGSREPORT-4036] Wk 0918 GPS Earth Orientation

[Dennis]

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IGS Electronic Report    Thu Aug 14  9:54:53 PDT 1997      Message Number 4036
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Author: Dennis McCarthy
Subject: Wk 0918 GPS Earth Orientation

From: Dennis McCarthy
Subject: Earth Orientation Contributions to IERS Bulletin A
Date: 14 Aug 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.    50668.67    23               -.014                .034

NEOS VLBI    50666.25     5   -.06  -.10   .004    .10   .07   .009

JPL VLBI     50667.22     6               -.007                .085

CSR SLR      50670.34    10   -.21   .08   .038    .22   .22   .052

TUD SLR      50610.00     7    .08   .17           .55   .21

UT LLR       50627.17    10               -.006                .080

IGS Final    50662.50    30    .06   .00           .07   .10

IGS Rapid    50672.50    10    .03   .01           .05   .11

             50672.50     4                .003                .058

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           50662.5    30   -.31  -.19           .17   .21

CODE          50669.5    30   -.27   .10 -17.46    .13   .19    .14

JPL           50662.5    30   -.18  -.10  -1.23    .12   .15    .59

ESOC          50662.5    30    .00  -.26           .14   .18

NRCan         50669.5    30   -.17  -.54  10.92    .16   .20    .07

GFZ           50669.5    30   -.33  -.36   -.05    .08   .19    .07

NOAA          50671.5    30   -.53  -.33           .50   .60

USNO          50672.5    30   -.56  -.58           .21   .41

IGS Final     50662.5    30   -.24  -.17    .00    .07   .11    .01

IGS Rapid     50672.5    30   -.30  -.26   -.04    .15   .22    .08

IERS Central Bureau Series:

Bulletin B    50634.     30   -.02   .01   .000    .11   .14   .016

97C04         50670.     30    .01   .05   .006    .12   .13   .061


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>]