[IGSREPORT-1000] GPS Earth Orientation

[Dennis]

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IGS Electronic Report    Thu Jun  2  9:44:25 PDT 1994      Message Number 1000
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Author: Dennis McCarthy / USNO
Subject: GPS Earth Orientation

>From:     Dennis McCarthy
Subject:  Preliminary look at GPS Earth orientation
Date:     2 June 1994


An updated look at Earth orientation data submitted to the IERS
follows.  Data reduced in the ITRF92 have been used where available. 
Means refer to the ITRF92 for those contributors who have reported
estimates in the ITRF92 (CODE, ESOC, EMR, JPL, and GFZ).  Units are
milliseconds of arc for x and y, and milliseconds of time for
UT1-UTC.


Contributor Data Span Points       Mean          Standard Deviation
                                (NEOS-GPS)
                              x     y  UT1-UTC    x     y  UT1-UTC

Scripps      48780.5   711  -1.55 -1.54          0.80  0.85
             -49493.5

CODE         48792.5   708   0.16 -1.13  -0.22   0.66  0.79  2.39
             -49499.5

JPL          48794.5   668   0.03 -1.32          0.62  0.64
             -49493.5

ESOC         48794.5   707  -0.22 -1.69          1.05  1.27
             -49500.5

NRCan        48830.5   625  -0.03 -0.71          0.59  0.74
             -49500.5
                       480                0.15               0.81

GFZ          48997.5   501  -0.38 -1.48          0.36  0.35
             -49493.5

NOAA         48988.5   500  -0.53 -1.49          1.10  1.29
             -49498.5

Plots of the residuals are available by FAX to anyone interested.

     Below is the same information as above provided for only the
last thirty data points sent by each contributor.

Contributor Data Span              Mean          Standard Deviation
                                (NEOS-GPS)
                              x     y  UT1-UTC    x     y  UT1-UTC

Scripps      49464.5        -0.35 -1.42          0.44  0.51
             -49493.5

CODE         49470.5         0.04 -1.02  -3.76   0.46  0.41  0.09
             -49499.5

JPL          49464.5         0.09 -1.61          0.32  0.33
             -49493.5

ESOC         49471.5        -0.27 -1.50          0.45  0.41
             -49500.5

NRCan        49471.5        -0.23 -0.73          0.31  0.46
             -49500.5

             49469.5                      1.17               0.05
             -49500.5 

GFZ          49464.5        -0.62 -1.47          0.38  0.35
             -49493.5

NOAA         49469.5        -0.18 -1.08          0.80  0.88 
             -49498.5
--
Dennis D. McCarthy                       dmc at maia.usno.navy.mil
Director, Earth Orientation Department   phone: (202) 653-0066
U.S. Naval Observatory                   fax: (202) 653-0587
Washington, DC 20392-5420