[IGSREPORT-4145] Wk 0923 GPS Earth Orientation

[Dennis]

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IGS Electronic Report    Thu Sep 18 11:45:35 PDT 1997      Message Number 4145
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Author: Dennis McCarthy
Subject: Wk 0923 GPS Earth Orientation

From: Dennis McCarthy
Subject: Earth Orientation Contributions to IERS Bulletin A
Date: 18 Sep 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.    50706.72    23                .008                .036

NEOS VLBI    50701.25     6   -.04  -.14  -.001    .24   .11   .007

JPL VLBI     50705.85     9               -.014                .132

CSR SLR      50705.63    11   -.12   .05  -.015    .20   .25   .051

TUD SLR      50610.00     7    .11   .17           .57   .24

UT LLR       50627.17    10                .001                .083

IGS Final    50697.50    30    .05   .02           .11   .08

IGS Rapid    50707.50    10    .03  -.01           .11   .11

             50707.50     1                .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           50697.5    30   -.27  -.12           .17   .23

CODE          50704.5    30   -.31   .07 -17.35    .21   .19    .12

JPL           50697.5    30   -.15  -.09    .50    .19   .15    .28

ESOC          50697.5    30    .05  -.08           .25   .32

NRCan         50702.5    30   -.09  -.77  10.92    .22   .21    .07

GFZ           50704.5    30   -.38  -.16   -.05    .14   .17    .04

NOAA          50706.5    30   -.60  -.57           .42   .61

USNO          50705.5    30   -.80  -.67           .35   .39

USNO GPS UT1  50707.5    28                -.12                 .08

IGS Final     50697.5    30   -.25  -.15    .00    .12   .11    .02

IGS Rapid     50707.5    30   -.63  -.49   -.05    .35   .41    .07

IERS Central Bureau Series:

Bulletin B    50664.     30    .04   .03  -.013    .12   .14   .033

97C04         50708.     30   -.02  -.03   .012    .19   .21   .034


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>]