
Sunday


August 19, 2018

USNO TRF/EOP Solution 2008b

Global VLBI TRF/EOP
Solution 2008b
July 2008


Presented here is the U.S. Naval Observatory's 2008b global
solution. The Batch SOLVE solution used all available
multibaseline VLBI observations at 8.4 GHz (Xband) and 2.2 GHz
(Sband) from 1979 August 3 through 2008 June 23. This
included a total of 3763 diurnal sessions and 5,317,776
measurements of group delay. The BATCH control
file
2008b.cnt along with databases given in
2008b.arc were used to generate this solution. The output spool
file is
2008b.spl.gz. Plotted and tabulated below are the global and
session RMS values for the solution.
Earth Orientation Parameters
The Earth Orientation parameters: X and Y pole positions and
rates, UT1 angle and rate, and daily offsets in the nutation in
longitude and obliquity were estimated for each session
separately. Plotted and tabulated below are these data.
Pole Position X vs. Y: Jan. 2000
to June 23 2008 (
postscript ,
pdf ) 

Full EOP time series: X pole, Ypole, UT angle
(
postscript ,
pdf ) 

Full Nutation offset time series: Longitude and
Obliquity (
postscript ,
pdf ) 

Tabulated data.
Station and Source Positions
Positions of 616 sources were estimated as global
parameters. Sources which participated in 2 or more sessions, had 40 or
more good observations, and normalized residual delays less than 1.3
qualified for the list of global sources. Positions for an additional 339
sources were estimated for each session independently as local
parameters. A total of 138 sources were eliminated due to bad
data or insufficient number (<3) of observations. Positions and
velocites for 128 stations were estimated as global
parameters.
Tabulated data.
Comparisons
Shown below is a comparison of the USNO 2008b solution with
the
IERS C04_05 time series. A weighted leastsquares fit
to the difference plots and the weighted rms are shown on each plot.
Shown below is a comparison of the USNO 2008b solution with
the GSFC 2008a solution. A weighted leastsquares fit to
the difference plots and the weighted rms are shown on each plot.
Shown below is a comparison of the USNO 2008b solution with
the previous USNO 2008a solution. A weighted
leastsquares fit to
the difference plots and the weighted rms are shown on each plot.
This is an Official U.S. Navy Web Site

Need Help?

