**********************************************************************
This note dated 04 Jan 2007: Vol. XX No. 001
**********************************************************************
Starting with the 04 January 2007 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XX, No. 001 -- a new
version of the IVS combined series (ivs07r1e) is being used. The series
is a new product, produced by Sarah Boeckmann and Axel Nothnagel, that
combines the VLBI SINEX files for the IVS contributors.
The new IVS EOP file is available at
ftp://cddis.gsfc.nasa.gov/vlbi/ivsproducts/eops/ivs07r1e.eops.gz
The effect of this change on IERS Bulletin A polar motion values is
generally less than about 0.1 mas and 10 us in UT1-UTC.
We gratefully acknowledge the efforts of Sarah and Axel in putting this
product together.
**********************************************************************
This note dated 18 Jan 2007: Vol. XX No. 003
**********************************************************************
Starting with the 18 January 2007 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XX, No. 003 -- new
versions of the GSFC VLBI solutions (gsf2007a and gsfint19) are being used.
These series are part of the quarterly update procedures adopted by most
IVS VLBI Analysis Centers.
The new EOP series are available at:
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eops/gsf2007a.eops.gz
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eopi/gsfint19.eopi.gz
The associated solution descriptions are available at:
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eops/gsf2007a.eops.txt
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eopi/gsfint19.eopi.txt
More information about the new solutions gsf2007a and gsfint19 can be
found on the Web:
http://lacerta.gsfc.nasa.gov/vlbi/solutions/2007a/
http://lacerta.gsfc.nasa.gov/vlbi/solutions/int19/
The differences with respect to gsf2006d solution is
Atmopsheric gradients estimates are models with a linear spline with
the time span of 6 hours, versus 8 hours in gsf2006d.
The ILRS Series A SLR solution has also been incorporated into the
combination. This series is a combination of SLR Analysis Center
contributions.
We have also taken this opportunity to readjust the systematic errors
of several of our contributing series. This adjustment is necessary
to bring the individual series and also our combined series into closer
alignment with the IERS C04 system.
In addition, a change in the combination code was made to generate
more realistic error estimates for the most recent EOP estimates.
The cumulative effect of this change on IERS Bulletin A polar motion values
is generally less than about 0.1 mas and 10 us in UT1-UTC.
We gratefully acknowledge the efforts of:
the GSFC VLBI staff in generating this update;
the ILRS for creating this very useful series; and
Tom Johnson for creating the software for using the ILRS data and
for generating more realistic error estimates.
**********************************************************************
This note dated 25 Jan 2007: Vol. XX No. 004
**********************************************************************
Starting with the 25 January 2007 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XX, No. 004 -- a new
polar motion prediction algorithm is being used.
This new (LS+AR) algorithm, initially created by Wieslaw Kosek, uses a
combination of least-squares (LS) and autoregressive (AR) techniques
(Kosek et al., 2004). The least-squares is used to solve for the largely
deterministic annual and Chandler components (and their subharmonics). The
differences between the deterministic solution and the polar motion data
are then used in an AR scheme to predict stochastic processes. The polar
motion prediction is then a combination of the deterministic prediction
(derived from the LS solution) and the stochastic prediction (derived
from the AR solution). Note that in creating the LS prediction, Tom
Johnson solved for the coefficients of more subharmonics than are used
in the LS model.
The solution for more coefficients has created a more accurate long-
term prediction while the use of the AR process has increased the
accuracy of the short-term predictions. The result is that we expect
the new LS+AR prediction scheme to produce superior prediction results
for all prediction lengths.
We gratefully acknowledge the efforts of Wieslaw and Tom for creating
the software for the new polar motion predictions.
Kosek W., McCarthy D.D., Johnson T.J., Kalarus M., 2004, "Comparison of
polar motion prediction results supplied by the IERS Sub-bureau for Rapid
Service and Predictions and results of other prediction methods." Proc.
Journes Systemes de Reference Spatio-Temporels 2003 "Astrometry, geodynamics
and Solar system dynamics: from milliarcseconds to microarcseconds",
A.Finkelstein and N.Capitaine (eds.), Inst. of Applied Astronomy of the
Russian Acad. of Sciences, St. Petersburg, 164-169.
**********************************************************************
This note dated 08 Feb 2007: Vol. XX No. 006
**********************************************************************
Starting with the 08 February 2007 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XX, No. 006 -- a new
version of the IAA VLBI solutions (iaa2007a) is being used.
The differences of the new iaa2007a solution with respect to the old
iaa2005a solution are:
- ITRF2005 is used for station positions
(associated velocity field is used for station
coordinates, ZELENCHK station was added to ITRF2005 catalog,
- VMF1 mapping function is used and bad meteodata are replaced
by values from VMF1.dat files.
- New Fortran routine, written by Duncan Agnew (UCSD) for local
site displacements due to ocean tidal loading is applied in agreement
with IERS Conventions 2003.
The effect of this change on IERS Bulletin A polar motion values is
generally less than about 0.1 mas and 10 us in UT1-UTC.
We gratefully acknowledge the efforts of Elena Skurikhina and Sergey
Kurdubov in generating this update.
**********************************************************************
This note dated 01 Mar 2007: Vol. XX No. 009
**********************************************************************
Starting with the 01 March 2007 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XX, No. 009 -- a new
version of the IGS Final solution (igs00p03) is being used.
The effect of this change on IERS Bulletin A polar motion values is
generally less than about 0.1 mas and 10 us in UT1-UTC.
**********************************************************************
This note dated 08 Mar 2007: Vol. XX No. 010
**********************************************************************
Starting with the 08 March 2007 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XX, No. 010 -- new
versions of the USNO VLBI series (usno2007a and int2007a) are being used.
The new USNO VLBI solutions are available at
http://rorf.usno.navy.mil/solutions/
Information, comparisons, and statistics for the new solutions can
be found at
http://rorf.usno.navy.mil/solutions/2007a/
and
http://rorf.usno.navy.mil/solutions/i2007a/
The effect of this change on IERS Bulletin A polar motion values is
generally less than about 0.1 mas and 10 us in UT1-UTC.
We gratefully acknowledge the efforts of Dave Boboltz and Alan Fey
in generating this update.
**********************************************************************
This note dated 29 Mar 2007: Vol. XX No. 013
**********************************************************************
Starting with the 29 March 2007 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XX, No. 013 -- new
versions of the GSFC VLBI solutions (gsf2007b and gsfint20) are being used.
These series are part of the quarterly update procedures adopted by most
IVS VLBI Analysis Centers.
The EOP series are available at:
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eops/gsf2007b.eops.gz
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eopi/gsfint20.eopi.gz
The associated solution descriptions are available at:
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eops/gsf2007b.eops.txt
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eopi/gsfint20.eopi.txt
More information about the new solutions gsf2007b and gsfint20 can be
found on the Web:
http://lacerta.gsfc.nasa.gov/vlbi/solutions/2007b/
http://lacerta.gsfc.nasa.gov/vlbi/solutions/int20/
The differences with respect to gsf2007a solution is
New stations DSS13 and BADARY were added.
The cumulative effect of this change on IERS Bulletin A polar motion values
is generally less than about 0.1 mas and 10 us in UT1-UTC.
We gratefully acknowledge the efforts of the GSFC VLBI staff in generating
this update.
**********************************************************************
This note dated 13 Jun 2007: Vol. XX No. 024
**********************************************************************
Starting with the 14 June 2007 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XX, No. 024 -- the
new 05 C04 system of the IERS is adopted.
The International Earth Rotation and Reference System Service (IERS) has
recently adopted the International Terrestrial Reference Frame (ITRF) 2005.
The ITRF 2005 was created through a process that combined simultaneously
positions and Earth orientation parameters (EOPs). The resulting ITRF/EOP
series results in improved consistency between the TRF and the EOP data.
In the process, this approach has shown that there is an inconsistency
between the older ITRFs and the older EOP systems, such as the 97 C04. In
order to eliminate this inconsistency, a new EOP system, called the 05 C04,
will be adopted by the IERS in the beginning of June. Adopting this new
system will result in a change of ~0.05 mas in the polar motion x-component
and ~0.30 mas in the polar motion y-component of the IERS EOP data. Note
that this corresponds roughly 3 cm at the Earth's equator and 13 cm at GPS
orbit.
The IERS Rapid Service/Prediction Center (RS/PC), located at the U.S. Naval
Observatory (USNO), implemented this change in system on 14 June. If
IERS RS/PC solutions from before this date are compared to solutions after
this date, small, systematic changes will be seen. These changes will be
less than 0.5 mas and should not impact most users.
Note that after 14 June, the entire finals.data set will be consistent with
the 05 C04 to within the errors of the data.
In addition to the change in system a small bias in the IGS data have been
corrected. This bias is due to the adoption on MJD 54044 of absolute
antenna phase center calibration. The ad hoc corrections have been
determined to be
IGS Final
PM-x 0.036 mas
PM-y 0.008 mas
IGS Rapid
PM-x 0.043 mas
PM-y -0.018 mas
**********************************************************************
This note dated 21 Jun 2007: Vol. XX No. 025
**********************************************************************
Starting with the 21 June 2007 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XX, No. 025 -- the
floor for the errors of the IGS series have been reduced. For the IGS
Finals (igs00p03), the floor has been reduced from 50 uas to 25 uas and
for the IGS Rapids (igs96p02), the floor has been reduced from 100 uas
to 50 uas. We believe these new estimates to be more consistant with
the current data quality than the older values.
These floor values are combined in an rss sense with the scaled formal
errors to create an error estimate for each data point. Since the
error estimates are then used as weights for the data, the decreased
error estimates should increase the weight given to the IGS data in the
combination solution. The resulting change in the combination solution
appears to be less than 10 uas in polar motion.
**********************************************************************
This note dated 12 Jul 2007: Vol. XX No. 028
**********************************************************************
Starting with the 12 July 2007 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XX, No. 028 -- the
ftp version of the IAA SLR data has been incorporated into the solution.
Specifically, we are now using the file
ftp://quasar.ipa.nw.ru/pub/EOS/IAA/slr.dat
in the daily and weekly combination procedures.
We have also taken this opportunity to update the systematic corrections
for the IAA SLR series. The old corrections
bias slope
-1.2942D-04 .0000D+00 PM-x
1.6832D-04 .0000D+00 PM-y
have been changed to
bias slope
-1.0510D-04 .0000D+00 PM-x
1.8090D-04 .0000D+00 PM-y
We gratefully acknowledge the information and assistance provided by
Elena Skurikhina which has been instrumental in allowing us to make
this change.
**********************************************************************
This note dated 19 Jul 2007: Vol. XX No. 029
**********************************************************************
Starting with the 19 July 2007 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XX, No. 029 -- the
IGS Ultra solution igu00p01 has been incorporated into the polar motion
solution. It is being used as an extension to the IGS Rapid solution
so only those data beyond the latest IGS Rapid point are being utilized.
The systematic corrections for the IGS Ultra series are
bias slope
-1.7300D-05 .0000D+00 PM-x
2.7200D-05 .0000D+00 PM-y
**********************************************************************
This note dated 26 Jul 2007: Vol. XX No. 030
**********************************************************************
Starting with the 26 July 2007 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XX, No. 030 -- new
versions of the USNO VLBI series (usno2007b and int2007b) are being used.
The new USNO VLBI solutions are available at
http://rorf.usno.navy.mil/solutions/
Information, comparisons, and statistics for the new solutions can
be found at
http://rorf.usno.navy.mil/solutions/2007b/
and
http://rorf.usno.navy.mil/solutions/i2007b/
We have also modified the systematic corrections for the new USNO VLBI
series. The old corrections
int2007a
bias slope
6.5220D-06-2.8626D-09 UT1-UTC
usno2007a
bias slope
1.2673D-04 3.8478D-08 PM-x
-4.2254D-05-2.7198D-09 PM-y
-8.4806D-07 1.7895D-09 UT1-UTC
have been changed to
int2007b
bias slope
7.6216D-06-3.6722D-09 UT1-UTC
usno2007b
bias slope
1.2611D-04 4.0188D-08 PM-x
-4.3378D-05-1.5629D-09 PM-y
-9.3827D-07 1.7987D-09 UT1-UTC
The effect of these changes on IERS Bulletin A polar motion values is
generally less than about 0.1 mas and 10 us in UT1-UTC.
We gratefully acknowledge the efforts of Dave Boboltz and Alan Fey
in generating this update.
**********************************************************************
This note dated 02 Aug 2007: Vol. XX No. 031
**********************************************************************
Starting with the 02 August 2007 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XX, No. 031 -- new
versions of the USNO VLBI series (gsf2007c and gsfint21) are being used.
Information, comparisons, and statistics for the new solutions can
be found at
http://vlbi.gsfc.nasa.gov/solutions/2007c/
and
http://vlbi.gsfc.nasa.gov/solutions/int21/
The difference with respect to gsf2007b solution is
New station BADARY was added.
We have also modified the systematic corrections for the new GSFC VLBI
series. The old corrections
gsfint20
bias slope
9.7357D-06-5.9401D-10 UT1-UTC
gsf2007b
bias slope
3.2098D-05-4.2437D-08 PM-x
1.8961D-04 3.4055D-08 PM-y
6.3655D-06 1.7026D-09 UT1-UTC
have been changed to
gsfint21
bias slope
-4.5799D-06 1.2293D-09 UT1-UTC
gsf2007c
bias slope
6.0671D-05 3.9240D-08 PM-x
-1.3267D-04-8.2718D-08 PM-y
-1.3091D-06 4.5978D-10 UT1-UTC
The effect of these changes on IERS Bulletin A polar motion values is
generally less than about 0.1 mas and 10 us in UT1-UTC.
We gratefully acknowledge the efforts of Karen Baver, David Gordon,
Chopo Ma, Dan MacMillian, and Leonid Petrov in generating this update.
**********************************************************************
This note dated 04 Oct 2007: Vol. XX No. 040
**********************************************************************
Starting with the 04 October 2007 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XX, No. 040 -- an
additional 2.5 days of AAM forecasts have been incorporated into the
combination and prediction procedures.
This has been made possible by the extension from 5 days to 7.5 days of
both the U.S. Navy Operational Global Atmospheric Prediction System
(NOGAPS) and the National Oceanic and Atmospheric Administration (NOAA)
AAM forecasts. These extensions could then be incorporated into the
combined AAM product used in the combination and predictions procedures.
We gratefully acknowledge the efforts of Tim Hogan and Jeffrey Lerner
to extend the NOGAPS AAM forecasts and Craig Long and Roger Lin to extend
the NOAA AAM forecasts.
**********************************************************************
This note dated 15 Nov 2007: Vol. XX No. 046
**********************************************************************
Starting with the 15 November 2007 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XX, No. 046 -- new
versions of the USNO VLBI series (usno2007c and int2007c) are being used.
The new USNO VLBI solutions are available at
http://rorf.usno.navy.mil/solutions/
Information, comparisons, and statistics for the new solutions can
be found at
http://rorf.usno.navy.mil/solutions/2007c/
and
http://rorf.usno.navy.mil/solutions/i2007c/
We have also modified the systematic corrections for the new USNO VLBI
series. The old corrections
int2007b
bias slope
7.6216D-06-3.6722D-09 UT1-UTC
usno2007b
bias slope
1.2611D-04 4.0188D-08 PM-x
-4.3378D-05-1.5629D-09 PM-y
-9.3827D-07 1.7987D-09 UT1-UTC
have been changed to
int2007c
bias slope
-2.4378D-06-1.7963D-10 UT1-UTC
usno2007c
bias slope
1.4314D-04 4.1352D-08 PM-x
-4.6101D-05 6.0060D-09 PM-y
-4.2756D-06 1.3822D-09 UT1-UTC
The effect of these changes on IERS Bulletin A polar motion values is
generally less than about 0.1 mas and 10 us in UT1-UTC.
We gratefully acknowledge the efforts of Dave Boboltz and Alan Fey
in generating this update.
**********************************************************************
This note dated 22 Nov 2007: Vol. XX No. 047
**********************************************************************
Starting with the 22 November 2007 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XX, No. 047 -- new
versions of the GSFC VLBI solutions (gsf2007d and gsfint22) are being used.
These series are part of the quarterly update procedures adopted by most
IVS VLBI Analysis Centers.
The new EOP series are available at:
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eops/gsf2007d.eops.gz
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eopi/gsfint22.eopi.gz
The associated solution descriptions are available at:
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eops/gsf2007d.eops.txt
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eopi/gsfint22.eopi.txt
More information about the new solutions gsf2007d and gsfint22 can be
found on the Web:
http://vlbi.gsfc.nasa.gov/vlbi/solutions/2007d/
http://vlbi.gsfc.nasa.gov/vlbi/solutions/int22/
The differences between the 2007d and 2007c solutions are
1) Additional available data since the 2007c solution was used, and
2) Mean pole offsets for pole tide are in agreement with the IERS Conventions
(2003) recommended values.
We gratefully acknowledge the efforts of the GSFC VLBI staff in generating
this update.
**********************************************************************
This note dated 29 Nov 2007: Vol. XX No. 048
**********************************************************************
Starting with the 29 November 2007 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XX, No. 048 -- the
the errors of the IGS Finals series have been reduced. Due to a problem
with the code, the estimated errors for the IGS Finals have been persistently
high. We believe these new estimates to be more consistant with the current
data quality than the older values.
Since the error estimates are then used as weights for the data, the
decreased error estimates should increase the weight given to the IGS Finals
data in the combination solution. The resulting change in the combination
solution appears to be less than 10 uas in polar motion.
**********************************************************************
This note dated 28 Feb 2008: Vol. XXI No. 009
**********************************************************************
Starting with the 28 February 2008 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXI, No. 009 -- new
versions of the USNO VLBI series (usno2008a and int2008a) are being used.
The new USNO VLBI solutions are available at
http://rorf.usno.navy.mil/solutions/
Information, comparisons, and statistics for the new solutions can
be found at
http://rorf.usno.navy.mil/solutions/2008a/
and
http://rorf.usno.navy.mil/solutions/i2008a/
We have also modified the systematic corrections for the new USNO VLBI
series. The old corrections
int2007c
bias slope
-2.4378D-06-1.7963D-10 UT1-UTC
usno2007c
bias slope
1.4314D-04 4.1352D-08 PM-x
-4.6101D-05 6.0060D-09 PM-y
-4.2756D-06 1.3822D-09 UT1-UTC
have been changed to
int2008a
bias slope
-2.8860D-06-5.4863D-10 UT1-UTC
usno2008a
bias slope
1.4212D-04 4.0692D-08 PM-x
-4.4930D-05 5.1610D-09 PM-y
-3.6893D-06 1.4456D-09 UT1-UTC
The effect of these changes on IERS Bulletin A polar motion values is
generally less than about 0.1 mas and 10 us in UT1-UTC.
We gratefully acknowledge the efforts of Dave Boboltz and Alan Fey
in generating this update.
**********************************************************************
This note dated 12 Jun 2008: Vol. XXI No. 024
**********************************************************************
Starting with the 12 June 2008 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXI, No. 024 -- new
versions of the GSFC VLBI solutions (gsf2008a and gsfint23) are being used.
These series are part of the quarterly update procedures adopted by most
IVS VLBI Analysis Centers.
The new EOP series are available at:
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eops/gsf2008a.eops.gz
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eopi/gsfint23.eopi.gz
The associated solution descriptions are available at:
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eops/gsf2008a.eops.txt
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eopi/gsfint23.eopi.txt
More information about the new solutions gsf2008a and gsfint23 can be
found on the Web:
http://vlbi.gsfc.nasa.gov/vlbi/solutions/2008a/
http://vlbi.gsfc.nasa.gov/vlbi/solutions/int23/
We have also modified the systematic corrections for the new GSFC VLBI
series. The old corrections
gsfint22
bias slope
-2.0065D-06-3.8554D-10 UT1-UTC
gsf2007d
bias slope
1.7743D-05-1.4033D-08 PM-x
8.8543D-06 1.3471D-08 PM-y
-2.2016D-06 7.7288D-10 UT1-UTC
have been changed to
gsfint23
bias slope
-8.1681D-06 2.2398D-09 UT1-UTC
gsf2008a
bias slope
2.7714D-05-9.6846D-08 PM-x
-1.0043D-06 6.0091D-09 PM-y
-3.5550D-06 7.7897D-10 UT1-UTC
We gratefully acknowledge the efforts of the GSFC VLBI staff in generating
this update.
**********************************************************************
This note dated 05 Mar 2009: Vol. XXII No. 009
**********************************************************************
Starting with the 05 March 2009 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXII, No. 009 -- a
new version of the USNO UTGPS solution is being used. This new series
utilizes more satellites than the older UTGPS solution (typically 15-25
versus <10) and more sophisticated orbital modeling. The result is that
the new UTGPS solution produces better UT estimates. Tests indicate that
the combination solution using the new UTGPS data are more accurate and
therefore lead to better UT1-UTC predictions.
We gratefully acknowledge the efforts of Jeffrey Tracey and Peter Kammeyer
in generating this new solution.
**********************************************************************
This note dated 19 Nov 2009: Vol. XXII No. 046
**********************************************************************
Starting with the daily run on 20 Nov 2009 which followed the
19 Nov 2009 issue of IERS Bulletin A (Rapid Service/ Predictions
of Earth Orientation information) -- Vol. XXII, No. 046 -- new versions
of the GSFC VLBI solutions (gsf2009a and gsfint24) are being used.
These series are part of the quarterly update procedures adopted by
most IVS VLBI Analysis Centers.
The new EOP series are:
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eops/gsf2009a.eops.gz
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eopi/gsfint24.eopi.gz
The solution descriptions are:
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eops/gsf2009a.eops.txt
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eopi/gsfint24.eopi.txt
We have also modified the systematic corrections for the new GSFC VLBI
series. The old corrections
gsfint23
bias slope
-8.1681D-06 2.2398D-09 UT1-UTC
gsf2008a
bias slope
2.7714D-05-9.6846D-08 PM-x
-1.0043D-06 6.0091D-09 PM-y
-3.5550D-06 7.7897D-10 UT1-UTC
have been changed to:
gsfint24
bias slope
-8.6258D-06 3.2901D-09 UT1-UTC
gsf2009a
bias slope
2.2725D-05-5.6502D-09 PM-x
-2.2053D-06-3.2692D-09 PM-y
-3.3445D-06 8.6498D-10 UT1-UTC
We gratefully acknowledge the efforts of the GSFC VLBI staff in generating
this update.
**********************************************************************
This note dated 25 Feb 2010: Vol. XXIII No. 008
**********************************************************************
Starting with the 25 February 2010 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXIII, No. 008 -- new
versions of the USNO VLBI series (usno2010a and int2010a) are being used.
The new USNO VLBI solutions are available at
http://rorf.usno.navy.mil/solutions/
Information, comparisons, and statistics for the new solutions will
soon be available at
http://rorf.usno.navy.mil/solutions/2010a/
and
http://rorf.usno.navy.mil/solutions/i2010a/
We have also modified the systematic corrections for the new USNO VLBI
series. The old corrections
int2008a
bias slope
-2.8860D-06-5.4863D-10 UT1-UTC
usno2008a
bias slope
1.4212D-04 4.0692D-08 PM-x
-4.4930D-05 5.1610D-09 PM-y
-3.6893D-06 1.4456D-09 UT1-UTC
have been changed to
int2010a
bias slope
-9.1277D-06 3.1561D-09
usno2010a
bias slope
-1.1966D-05-1.6190D-08
-6.0178D-05-4.0753D-08
-3.1767D-06 5.1229D-10
The effect of these changes on IERS Bulletin A polar motion values is
generally less than about 0.1 mas and 10 us in UT1-UTC.
We gratefully acknowledge the efforts of Dave Boboltz and Alan Fey
in generating this update.
**********************************************************************
This note dated 25 Feb 2010: Vol. XXIII No. 008
**********************************************************************
A revised method of processing AAM data has been implemented.
Users should see an improvement in the combination and short-term
prediction of UT1-UTC for both the Bulletin and future rapid
finals results. The AAM inputs were removed from the UT1-UTC combination
except for the one corresponding to the last combination point.
The AAM inputs are still used as a valuable part of the
EOP UT1-UTC prediction process.
**********************************************************************
This note dated 11 Mar 2010: Vol. XXIII No. 010
**********************************************************************
Starting with the 11 March 2010 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXIII, No. 010 -- new
systematic corrections for the IVS 24 hour VLBI (ivs07r1X.eops) series
have been implemented.
The old corrections
bias slope
1.3407D-05 7.0012D-09 PM-x
-4.0606D-05 1.9782D-08 PM-y
9.0360D-06-5.3727D-09 UT1-UTC
have been changed to
bias slope
1.0304D-04-2.8902D-08 PM-x
1.3346D-04-5.7267D-08 PM-y
-3.1474D-06 3.9162D-10 UT1-UTC
The effect of these changes on IERS Bulletin A polar motion values is
generally less than about 0.1 mas and 10 us in UT1-UTC.
**********************************************************************
This note dated 18 Mar 2010: Vol. XXIII No. 011
**********************************************************************
Starting with the 18 March 2010 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXIII, No. 011 -- new
systematic corrections for the IAA 24 hour VLBI (iaa2007a.eops) series
have been implemented.
The old corrections
bias slope
2.0692D-05 1.1467D-09 PM-x
-1.4875D-05-7.1680D-09 PM-y
-1.0863D-06-4.3902D-10 UT1-UTC
have been changed to
bias slope
1.3338D-05 5.1801D-09 PM-x
-3.5150D-06-1.3897D-08 PM-y
-1.1810D-06-6.3602D-10 UT1-UTC
The effect of these changes on IERS Bulletin A polar motion values is
generally less than about 0.1 mas and 10 us in UT1-UTC.
**********************************************************************
This note dated 17 Jun 2010: Vol. XXIII No. 024
**********************************************************************
Starting with the 17 Jun 2010 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXIII, No. 024 -- new
versions of the GSFC VLBI solutions (gsf2010a.eops and gsf2010.eopi) are
being used. These series are part of the quarterly update procedures
adopted by most IVS VLBI Analysis Centers.
The new EOP series are:
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eops/gsf2010a.eops.gz
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eopi/gsf2010a.eopi.gz
The solution descriptions are:
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eops/gsf2010a.eops.txt
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eopi/gsf2010a.eopi.txt
We have also modified the systematic corrections for the new GSFC VLBI
series. The old corrections
gsfint24
bias slope
-8.6258D-06 3.2901D-09 UT1-UTC
gsf2009a
bias slope
2.2725D-05-5.6502D-09 PM-x
-2.2053D-06-3.2692D-09 PM-y
-3.3445D-06 8.6498D-10 UT1-UTC
have been changed to:
gsf2010a.eopi
bias slope
-3.4996D-06 1.1847D-09 UT1-UTC
gsf2010a.eops
bias slope
6.9522D-06 2.3267D-09 PM-x
-3.8764D-05-8.9746D-09 PM-y
-1.6178D-06 1.0139D-11 UT1-UTC
The effect of these changes on IERS Bulletin A polar motion values is
generally less than about 0.1 mas and 10 us in UT1-UTC.
We gratefully acknowledge the efforts of the GSFC VLBI staff in generating
this update.
**********************************************************************
This note dated 5 Aug 2010: Vol. XXIII No. 031
**********************************************************************
Starting with the 5 Aug 2010 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXIII, No. 031 -- the
GSI VLBI INT2 solution gsi.eopi has been incorporated into the UT1-UTC
solution.
The series are available at:
ftp://www.spacegeodesy.go.jp/
http://www.spacegeodesy.go.jp/eopi/
The systematic corrections for the GSI VLBI INT2 series are
gsi.eopi
bias slope
-3.0417D-06 -5.8577D-10 UT1-UTC
The effect of these changes on IERS Bulletin A UT1-UTC values is
generally less than 10 us in UT1-UTC.
We gratefully acknowledge the efforts of our colleagues at GSI for generating
this series.
**********************************************************************
This note dated 18 Nov 2010: Vol. XXIII No. 046
**********************************************************************
Starting with the 18 November 2010 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXIII, No. 046 -- new
systematic corrections for the IVS 24 hour VLBI (ivs07r1X.eops) series
have been implemented.
The old corrections
bias slope
1.0304D-04-2.8902D-08 PM-x
1.3346D-04-5.7267D-08 PM-y
-3.1474D-06 3.9162D-10 UT1-UTC
have been changed to
bias slope
1.1107D-04-3.3457D-08 PM-x
1.0685D-04-4.6435D-08 PM-y
-4.0560D-06 5.0919D-10 UT1-UTC
The effect of these changes on IERS Bulletin A polar motion values is
generally less than about 0.1 mas and 10 us in UT1-UTC.
**********************************************************************
This note dated 01 Feb 2011:
**********************************************************************
Starting with the daily run on 01 February 2011, the new 08 C04 system of the
IERS is adopted. The finals.daily, finals.data, gpsrapid.daily, gpsrapid.out
and all finals2000A series solutions have adopted the new system. On 03
February 2011, Bulletin A Vol. XXIV, No. 005, and future Bulletin A series
results will adopt the new 08 C04 system.
The International Earth Rotation and Reference System Service (IERS) has
recently adopted the International Terrestrial Reference Frame (ITRF) 2008.
The ITRF 2008 was created through a process that combined simultaneously
positions and Earth orientation parameters (EOPs). The resulting ITRF/EOP
series results in improved consistency between the TRF and the EOP data.
In the process, this approach has shown that there is an inconsistency
between the older ITRFs and the older EOP systems, such as the 05 C04. In
order to eliminate this inconsistency, a new EOP system, called the 08 C04,
will be adopted by the IERS in the beginning of February. Adopting this new
system will result in a change of less than 0.1 mas in polar motion and
10 us in UT1-UTC. Note that this corresponds to ~ 0.3 cm at the Earth's
surface and ~ 1.3 cm at GPS orbit. The IERS Rapid Service/Prediction Center
(RS/PC), located at the U.S. Naval Observatory (USNO), implemented this change
in system on 01 February.
**********************************************************************
This note dated 21 April 2011: Vol. XXIV No. 016
**********************************************************************
Starting with the 21 April 2011 issue of IERS Bulletin A --
Vol. XXIV, No. 016 -- the IGS Ultra LOD solution has replaced
the IGS Rapid LOD solution usage in the UT1-UTC combination solution.
Note, only those Ultra epochs beyond the most recent
GSI, GSFC, and USNO VLBI intensive epoch are used.
**********************************************************************
This note dated 28 April 2011: Vol. XXIV No. 017
**********************************************************************
Starting with the 28 April 2011 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXIV, No. 017 -- new
versions of the GSFC VLBI solutions (gsf2011a.eops and gsf2011.eopi) are
being used. These series are part of the quarterly update procedures
adopted by most IVS VLBI Analysis Centers.
The new EOP series are:
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eops/gsf2011a.eops.gz
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eopi/gsf2011a.eopi.gz
The solution descriptions are:
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eops/gsf2011a.eops.txt
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eopi/gsf2011a.eopi.txt
We have also modified the systematic corrections for the new GSFC VLBI
series. The old corrections
gsf2010a.eopi
bias slope
-3.4996D-06 1.1847D-09 UT1-UTC
gsf2010a.eops
bias slope
6.9522D-06 2.3267D-09 PM-x
-3.8764D-05-8.9746D-09 PM-y
-1.6178D-06 1.0139D-11 UT1-UTC
have been changed to:
gsf2011a.eopi
bias slope
1.9558D-06 1.1629D-09 UT1-UTC
gsf2011a.eops
bias slope
9.9725D-05 1.7879D-09 PM-x
-9.6266D-05-1.2656D-08 PM-y
8.1261D-06-1.1058D-09 UT1-UTC
The effect of these changes on IERS Bulletin A polar motion values is
generally less than about 0.1 mas and 10 us in UT1-UTC.
We gratefully acknowledge the efforts of the GSFC VLBI staff in generating
this update.
**********************************************************************
This note dated 05 May 2011: Vol. XXIV No. 018
**********************************************************************
Starting with the 05 May 2011 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXIV, No. 018 -- new
versions of the USNO VLBI series (usno2011a and int2011a) are being used.
The new USNO VLBI solutions are available at
http://rorf.usno.navy.mil/solutions/
Information, comparisons, and statistics for the new solutions will
soon be available at
http://rorf.usno.navy.mil/solutions/2011a/
and
http://rorf.usno.navy.mil/solutions/i2011a/
We have also modified the systematic corrections for the new USNO VLBI
series. The old corrections
int2010a
bias slope
-2.8588D-06 2.5685D-09 UT1-UTC
usno2010a
bias slope
6.3176D-07-3.7887D-09
PM-x
-1.0004D-04-5.3092D-08
PM-y
8.6990D-07 1.8058D-10 UT1-UTC
have been changed to
int2011a
bias slope
-2.8572D-06 1.7026D-09
usno2010a
bias slope
-4.6826D-10-7.4261D-10 PM-x
-1.2198D-04-5.6520D-08 PM-y
1.4707D-06 2.9243D-11 UT1-UTC
The effect of these changes on IERS Bulletin A polar motion values is
generally less than about 0.1 mas and 10 us in UT1-UTC.
We gratefully acknowledge the efforts of Dave Boboltz and Alan Fey
in generating this update.
**********************************************************************
This note dated 19 May 2011: Vol. XXIV No. 020
**********************************************************************
Starting with the 19 May 2011 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXIV, No. 020 -- the
new version of the GSI VLBI intensive solution, gsi2011a.eopi, is being used.
The series are available at:
ftp://cddis.gsfc.nasa.gov/vlbi/ivsproducts/eopi/gsi2011a.eopi.gz
We have also modified the systematic corrections for the new GSI VLBI
intensive series. The old corrections
gsi.eopi
bias slope
-3.0417D-06 -5.8577D-10 UT1-UTC
have been changed to
gsi2011a.eopi
bias slope
1.4496D-05 -3.7932D-09 UT1-UTC
The effect of these changes on IERS Bulletin A UT1-UTC values is
generally less than 10 us in UT1-UTC.
We gratefully acknowledge the efforts of our colleagues at GSI for generating
this update.
**********************************************************************
This note dated 27 June 2011: Vol. XXIV No. 025
**********************************************************************
The dX and dY nutation error "floors" have been updated to reflect increased
quality of VLBI data over the last few years. Reported dX and dY values
in these files should now better reflect actual observational accuracies.
**********************************************************************
This note dated 01 December 2011: Vol. XXIV No. 048
**********************************************************************
Starting with the 01 December 2011 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXIV, No. 048 -- new
versions of the GSFC VLBI solutions (gsf2011b.eops and gsf2011b.eopi) are
being used.
The new EOP series are:
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eops/gsf2011b.eops.gz
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eopi/gsf2011b.eopi.gz
The solution descriptions are:
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eops/gsf2011b.eops.txt
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eopi/gsf2011b.eopi.txt
We have also modified the systematic corrections for the new GSFC VLBI
series. The old corrections
gsf2011a.eopi
bias slope
1.9558D-06 1.1629D-09 UT1-UTC
gsf2011a.eops
bias slope
9.9725D-05 1.7879D-09 PM-x
-9.6266D-05-1.2656D-08 PM-y
8.1261D-06-1.1058D-09 UT1-UTC
have been changed to:
gsf2011b.eopi
bias slope
4.4237D-06 6.5985D-10 UT1-UTC
gsf2011b.eops
bias slope
6.1363D-05 6.2285D-09 PM-x
-5.6439D-05-3.9864D-08 PM-y
4.7929D-06-3.5034D-10 UT1-UTC
The effect of these changes on IERS Bulletin A polar motion values is
generally less than about 0.1 mas and 10 us in UT1-UTC.
We gratefully acknowledge the efforts of the GSFC VLBI staff in generating
this update.
**********************************************************************
This note dated 19 July 2012: Vol. XXV No. 029
**********************************************************************
Starting with the 19 July 2012 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXV, No. 029 -- new
versions of the GSFC VLBI solutions (gsf2012a.eops and gsf2012a.eopi) are
being used.
The new EOP series are:
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eops/gsf2012a.eops.gz
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eopi/gsf2012a.eopi.gz
The solution descriptions are:
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eops/gsf2012a.eops.txt
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eopi/gsf2012a.eopi.txt
We have also modified the systematic corrections for the new GSFC VLBI
series. The old corrections
gsf2011b.eopi
bias slope
4.4237D-06 6.5985D-10 UT1-UTC
gsf2011b.eops
bias slope
6.1363D-05 6.2285D-09 PM-x
-5.6439D-05-3.9864D-08 PM-y
4.7929D-06-3.5034D-10 UT1-UTC
have been changed to:
gsf2012a.eopi
bias slope
2.603D-06 5.2502D-10 UT1-UTC
gsf2012a.eops
bias slope
1.9222D-05 4.6138D-11 PM-x
-9.2019D-06-1.5440D-09 PM-y
8.3026D-07-1.9773D-10 UT1-UTC
The effect of these changes on IERS Bulletin A polar motion values is
generally less than about 0.1 mas and 10 us in UT1-UTC.
We gratefully acknowledge the efforts of the GSFC VLBI staff in generating
this update.
**********************************************************************
This note dated 26 July 2012: Vol. XXV No. 030
**********************************************************************
Starting with the 26 July 2012 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXV, No. 030 -- new
versions of the USNO VLBI series (usno2012a and int2012a) are being used.
The new USNO VLBI solutions are available at
http://rorf.usno.navy.mil/solutions/
Information, comparisons, and statistics for the new solutions will
soon be available at
http://rorf.usno.navy.mil/solutions/
and
http://rorf.usno.navy.mil/solutions/
We have also modified the systematic corrections for the new USNO VLBI
series. The old corrections
int2011a
bias slope
-2.8572D-06 1.7026D-09
usno2011a
bias slope
-4.6826D-10-7.4261D-10 PM-x
-1.2198D-04-5.6520D-08 PM-y
1.4707D-06 2.9243D-11 UT1-UTC
have been changed to
int2012a
bias slope
-3.8283D-06 2.2855D-09 UT1-UTC
usno2012a
bias slope
2.6767D-05 1.3294D-08 PM-x
-9.2041D-05-3.9641D-08 PM-y
-1.6768D-06 1.2834D-09 UT1-UTC
The effect of these changes on IERS Bulletin A polar motion values is
generally less than about 0.1 mas and 10 us in UT1-UTC.
We gratefully acknowledge the efforts of the USNO AD staff
in generating this update.
**********************************************************************
This note dated 18 Oct 2012: Vol. XXV No. 042
**********************************************************************
Starting with the 26 July 2012 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXV, No. 030 -- new
versions of the USNO VLBI series (usno2012b and int2012b) are being used.
The new USNO VLBI solutions are available at
http://rorf.usno.navy.mil/solutions/
Information, comparisons, and statistics for the new solutions will
soon be available at
http://rorf.usno.navy.mil/solutions/
and
http://rorf.usno.navy.mil/solutions/
We have also modified the systematic corrections for the new USNO VLBI
series. The old corrections
int2012a
bias slope
-3.8283D-06 2.2855D-09 UT1-UTC
usno2012a
bias slope
2.6767D-05 1.3294D-08 PM-x
-9.2041D-05-3.9641D-08 PM-y
-1.6768D-06 1.2834D-09 UT1-UTC
have been changed to:
usno2012b
bias slope
-3.5406D-06 2.1529D-09 UT1-UTC
usno2012b
bias slope
4.0713D-05 1.7557D-08 PM-x
-8.2950D-05-3.7521D-08 PM-y
-2.1772D-06 1.1457D-09 UT1-UTC
The effect of these changes on IERS Bulletin A polar motion values is
generally less than about 0.1 mas and 10 us in UT1-UTC.
We gratefully acknowledge the efforts of the USNO AD staff
**********************************************************************
This note dated 29 Nov 2012: Vol. XXV No. 048
**********************************************************************
As of Bulletin A Vol. XXV, No. 048, on 29 Nov 2012, we have
upgraded the generation of UT1-UTC by incorporating a new tidal
model, which is consistent with IERS Conventions 2010. The effect
appears to be less than 30 us (RMS) in UT1-UTC.
**********************************************************************
This note dated 10 Jan 2013: Vol. XXVI No. 002
**********************************************************************
The IAA VLBI 24 hour PMx and UT1-UTC systematic corrections were updated.
The old corrections:
bias slope
2.7539D-05 1.4893D-08 PM-x
-4.8877D-05-2.1786D-08 PM-y
2.6483D-06-1.1671D-09 UT1-UTC
have been changed to:
bias slope
2.7993D-05 5.6412D-09 PM-x
-4.8877D-05-2.1786D-08 PM-y
2.3292D-06-4.0408D-10 UT1-UTC
**********************************************************************
This note dated 25 July 2013: Vol. XXVI No. 030
**********************************************************************
As of Bulletin A Vol. XXVI No. 030, on 25 July 2013, the contri-
bution of the US Navy Fleet Numerical Meteorology and Oceanography
Center (FNMOC) to the Atmospheric Angular Momentum (AAM)
inputs has been upgraded from the Navy Operational Global
Atmospheric Prediction System (NOGAPS) to the Navy Global
Environmental Model (NAVGEM). It is anticipated that this
upgrade should somewhat improve the short term UT1-UTC predictions.
**********************************************************************
This note dated 15 Aug 2013: Vol. XXVI No. 033
**********************************************************************
As of Bulletin A Vol. XXVI, No. 033, on 15 Aug 2013, we have
updated the IAA VLBI solution systematic corrections.
The effect appears to be less than 0.1 mas in polar motion
and 10 us in UT1-UTC.
The old corrections:
bias slope
2.7993D-05 5.6412D-09 IAA VLBI X
-4.8877D-05-2.1786D-08 IAA VLBI Y
2.3292D-06-4.0408D-10 IAA VLBI T
have been changed to:
bias slope
6.8220D-04-1.8257D-07 IAA VLBI X
-4.6915D-05-2.0738D-08 IAA VLBI Y
2.1812D-06-2.0581D-10 IAA VLBI T
**********************************************************************
This note dated 17 Oct 2013: Vol. XXVI No. 042
**********************************************************************
As of Bulletin A Vol. XXVI, No. 042, on 17 Oct 2013, we have
replaced the USNO GPS "UT" input based on the IGS rapids with
the USNO GPS "UT" input based on the "12-hour" IGS ultra-rapid
observations. The effect appears to be less than 10 us
in UT1-UTC.
**********************************************************************
This note dated 06 Feb 2014: Vol. XXVII No. 006
**********************************************************************
As of Bulletin A Vol. XXVII No. 006, on 06 Feb 2014, the contri-
bution of the US Navy Fleet Numerical Meteorology and Oceanography
Center (FNMOC) to the Atmospheric Angular Momentum (AAM)
inputs has been upgraded to version 1.2 of the Navy Global
Environmental Model (NAVGEM). It is anticipated that this
upgrade may somewhat improve the short term UT1-UTC predictions.
**********************************************************************
This note dated 22 May 2014: Vol. XXVII No. 021
**********************************************************************
Starting with the 22 May 2014 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXVII, No. 021 -- new
versions of the GSFC VLBI solutions (gsf2014a.eops and gsf2014a.eopi) are
being used.
The new EOP series are:
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eops/gsf2014a.eops.gz
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eopi/gsf2014a.eopi.gz
The solution descriptions are:
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eops/gsf2014a.eops.txt
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eopi/gsf2014a.eopi.txt
We have also modified the systematic corrections for the new GSFC VLBI
series. The old corrections
gsf2012a.eopi
bias slope
2.6030D-06 5.2502D-10 UT1-UTC
gsf2012a.eops
bias slope
1.9222D-05 4.6138D-11 PM-x
-9.2019D-06-1.5440D-09 PM-y
8.3026D-07-1.9773D-10 UT1-UTC
have been changed to:
gsf2014a.eopi
bias slope
4.9976D-06-2.9669D-10 UT1-UTC
gsf2014a.eops
bias slope
5.4894D-06 6.9722D-10 PM-x
-6.2628D-05 3.5091D-09 PM-y
3.0104D-06-5.3492D-10 UT1-UTC
The effect of these changes on IERS Bulletin A polar motion values is
generally less than about 0.1 mas and 10 us in UT1-UTC.
We gratefully acknowledge the efforts of the GSFC VLBI staff in generating
this update.
**********************************************************************
This note dated 05 Jun 2014: Vol. XXVII No. 023
**********************************************************************
Starting with the 05 Jun 2014 issues of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXVII, No. 023 -- new
versions of the USNO VLBI solutions (usno2014a.eops and usno2014a.eopi) are
being used.
The new EOP series are:
ftp://rorf.usno.navy.mil/EOP/last.eops
ftp://rorf.usno.navy.mil/EOP/int_last.eopi
We have also modified the systematic corrections for the new USNO VLBI
series. The old corrections:
last.eops
bias slope
4.0713D-05 1.7557D-08 PM-x
-8.2950D-05 -3.7521D-08 PM-y
-2.1772D-06 1.1457D-09 UT1-UTC
int_last.eopi
bias slope
-3.5406D-06 2.1529D-09 UT1-UTC
have been changed to:
last.eops
bias slope
2.5657D-04 1.0532D-08 PM-x
-5.4219D-05 6.1394D-10 PM-y
2.3453D-06 -4.0853D-10 UT1-UTC
int_last.eopi
bias slope
-1.1651D-07 5.7297D-10 UT1-UTC
We have also updated the systematic corrections for the ILRS SLR solution.
The old corrections:
1.8446D-03 -4.3597D-07 PM-x
-4.4809D-03 9.4751D-07 PM-y
have been changed to:
3.1514D-04 -8.4343D-08 PM-x
-1.1731D-03 2.2101D-07 PM-y
The cumulative effect of these changes on IERS Bulletin A polar motion values
is generally less than about 0.1 mas and 10 us in UT1-UTC.
We gratefully acknowledge the efforts of the USNO VLBI staff in generating
this update.
**********************************************************************
This note dated 30 Apr 2015: Vol. XXVIII No. 018
**********************************************************************
Starting with the 30 Apr 2015 issues of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXVIII, No. 018 -- new
versions of the USNO VLBI solutions (usno2015a.eops and usno2015a.eopi) are
being used.
The new EOP series are:
ftp://rorf.usno.navy.mil/EOP/last.eops
ftp://rorf.usno.navy.mil/EOP/int_last.eopi
We have also modified the systematic corrections for the new USNO VLBI
series. The old corrections:
last.eops
bias slope
2.5657D-04 1.0532D-08 PM-x
-5.4219D-05 6.1394D-10 PM-y
2.3453D-06 -4.0853D-10 UT1-UTC
int_last.eopi
bias slope
-1.1651D-07 5.7297D-10 UT1-UTC
have been changed to:
last.eops
bias slope
2.4896D-04 1.1331D-08 PM-x
-4.4005D-05 5.1977D-09 PM-y
5.6763D-06-8.9043D-10 UT1-UTC
int_last.eopi
bias slope
7.2867D-06 -6.7398D-10 UT1-UTC
The cumulative effect of these changes on IERS Bulletin A polar motion values
is generally less than about 0.1 mas and 10 us in UT1-UTC.
We gratefully acknowledge the efforts of the USNO VLBI staff in generating
this update.
**********************************************************************
This note dated 22 Oct 2015: Vol. XXVIII No. 043
**********************************************************************
As of Bulletin A Vol. XXVIII No. 043, on 22 Oct 2015, the contri-
bution of the US Navy Fleet Numerical Meteorology and Oceanography
Center (FNMOC) to the Atmospheric Angular Momentum (AAM)
inputs has been upgraded to version 1.3 of the Navy Global
Environmental Model (NAVGEM). It is anticipated that this
upgrade may somewhat improve the short term UT1-UTC predictions.
**********************************************************************
This note dated 10 Dec 2015: Vol. XXVIII No. 050
**********************************************************************
Starting with the 10 Dec 2015 issues of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXVIII, No. 050 -- new
versions of the USNO VLBI solutions (usno2015b.eops and usno2015b.eopi) are
being used.
The new EOP series are:
ftp://rorf.usno.navy.mil/EOP/last.eops
ftp://rorf.usno.navy.mil/EOP/int_last.eopi
Starting 11 Dec 2015, we have modified the systematic corrections for the
new USNO VLBI series. The old corrections:
last.eops
bias slope
2.4896D-04 1.1331D-08 PM-x
-4.4005D-05 5.1977D-09 PM-y
5.6763D-06-8.9043D-10 UT1-UTC
int_last.eopi
bias slope
7.2867D-06 -6.7398D-10 UT1-UTC
have been changed to:
last.eops
bias slope
2.6796D-04 6.1019D-09 PM-x
6.8612D-07 2.4309D-09 PM-y
3.4217D-06-9.7888D-10 UT1-UTC
int_last.eopi
bias slope
4.1047D-06 -4.1622D-10 UT1-UTC
The cumulative effect of these changes on IERS Bulletin A polar motion values
is generally less than about 0.1 mas and 10 us in UT1-UTC.
We gratefully acknowledge the efforts of the USNO VLBI staff in generating
this update.
**********************************************************************
This note dated 23 June 2016: Vol. XXIX No. 025
**********************************************************************
Starting with the 23 June 2016 issues of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXIX, No. 025 -- the
systematic corrections for the IAA VLBI input was updated for Polar Motion X.
Starting 23 June 2016, we have updated the systematic corrections for the
IAA VLBI series for Polar Motion X. The old corrections:
bias slope
6.8220D-04 -1.8257D-07 PM-x
have been changed to:
to:
bias slope
2.9572D-05 -4.7303D-09 PM-x
The cumulative effect of these changes on IERS Bulletin A polar motion values
is generally less than about 0.1 mas.
**********************************************************************
This note dated 13 Oct 2016: Vol. XXIX No. 041
**********************************************************************
Starting with the 13 Oct 2016 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXIX, No. 041 -- new
versions of the GSFC VLBI solutions (gsf2016a.eops and gsf2016a.eopi) are
being used.
The new EOP series are:
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eops/gsf2016a.eops.gz
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eopi/gsf2016a.eopi.gz
The solution descriptions are:
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eops/gsf2016a.eops.txt
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eopi/gsf2016a.eopi.txt
We have also modified the systematic corrections for the new GSFC VLBI
series. The old corrections
gsf2014a.eopi
bias slope
4.9976D-06-2.9669D-10 UT1-UTC
gsf2014a.eops
bias slope
5.4894D-06 6.9722D-10 PM-x
-6.2628D-05 3.5091D-09 PM-y
3.0104D-06-5.3492D-10 UT1-UTC
have been changed to:
gsf2016a.eopi
bias slope
6.1906D-06 3.4105D-10 UT1-UTC
gsf2016a.eops
bias slope
6.9027D-06 2.0514D-09 PM-x
-1.4334D-04 1.4895D-09 PM-y
1.3843D-05-1.0918D-09 UT1-UTC
The effect of these changes on IERS Bulletin A polar motion values is
generally less than about 0.1 mas and 10 us in UT1-UTC.
We gratefully acknowledge the efforts of the GSFC VLBI staff in generating
this update.
**********************************************************************
This note dated 13 Oct 2016: Vol. XXIX No. 041
**********************************************************************
As of Bulletin A Vol. XXIX No. 041, on 13 Oct 2016, the contri-
bution of the US Navy Fleet Numerical Meteorology and Oceanography
Center (FNMOC) to the Atmospheric Angular Momentum (AAM) inputs has been
upgraded to version 1.4 of the Navy Global Environmental Model (NAVGEM).
It is aniticpated that this upgrade may somewhat improve the short term
UT1-UTC predictions.
**********************************************************************
This note dated 17 Nov 2016: Vol. XXIX No. 046
**********************************************************************
Starting with the 17 Nov 2016 issues of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXIX, No. 046 -- new
versions of the USNO VLBI solutions (usno2016a.eops and usno2016a.eopi) are
being used.
The new EOP series are:
ftp://rorf.usno.navy.mil/EOP/last.eops
ftp://rorf.usno.navy.mil/EOP/int_last.eopi
Starting 17 Nov 2016, we have modified the systematic corrections for the
new USNO VLBI series. The old corrections:
last.eops
bias slope
2.6796D-04 6.1019D-09 PM-x
6.8612D-07 2.4309D-09 PM-y
3.4217D-06-9.7888D-10 UT1-UTC
int_last.eopi
bias slope
4.1047D-06 -4.1622D-10 UT1-UTC
have been changed to:
last.eops
bias slope
2.2437D-04 1.5983D-08 PM-x
-3.5101D-05 6.3772D-10 PM-y
-2.8466D-07 -6.4683D-10 UT1-UTC
int_last.eopi
bias slope
4.7215D-07 -5.4247D-10 UT1-UTC
The cumulative effect of these changes on IERS Bulletin A polar motion values
is generally less than about 0.1 mas and 10 us in UT1-UTC.
We gratefully acknowledge the efforts of the USNO VLBI staff in generating
this update.
**********************************************************************
This note dated 23 March 2017: Vol. XXX, No. 012
**********************************************************************
As of Bulletin A Vol. XXX, No. 012, on 23 March 2017, we transitioned the
he IERS RS/PC solution to be consistent with the ITRF 2014. This will result
in a jump of less than 0.1 mas in polar motion and 10 us in UT1-UTC. Small
adjustments to celestial pole offsets were also made in order to be more
consistent with the IVS VLBI combined series solution. The only users who
need to be concerned with this change are those who need EOP accuracy to
better than 0.1 mas (~0.3 cm at the Earth's surface, ~1.3 cm at GPS orbit).
The International Earth Rotation and Reference System Service (IERS) has
recently adopted the International Terrestrial Reference Frame (ITRF) 2014.
The ITRF 2014 was created through a process that combined simultaneously
positions and Earth orientation parameters (EOPs). The resulting ITRF/EOP
series results in improved consistency between the TRF and the EOP data.
**********************************************************************
This note dated 13 Oct 2016: Vol. XXIX No. 041
**********************************************************************
As of Bulletin A Vol. XXIX No. 041, on 13 Oct 2016, the contri-
bution of the US Navy Fleet Numerical Meteorology and Oceanography
Center (FNMOC) to the Atmospheric Angular Momentum (AAM) inputs has been
upgraded to version 1.4 of the Navy Global Environmental Model (NAVGEM).
It is aniticpated that this upgrade may somewhat improve the short term
UT1-UTC predictions.
**********************************************************************
This note dated 30 March 2017: Vol. XXX, No. 013
**********************************************************************
As of Bulletin A Vol. XXX, No. 013, on 30 March 2017, we have adjusted the
IERS RS/PC solution for UT1-UTC, resulting in a weighted average change of
less than 5 us.
This change in UT1-UTC is the result of deweighting the UTGPS contribution to
the IERS RS/PC solution.
**********************************************************************
This note dated 18 May 2017: Vol. XXX No. 020
**********************************************************************
Starting with the 18 May 2017 issues of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXX, No. 020 -- new
versions of the USNO VLBI solutions (usno2017a.eops and usno2017a.eopi) are
being used.
The new EOP series are:
ftp://rorf.usno.navy.mil/EOP/last.eops
ftp://rorf.usno.navy.mil/EOP/int_last.eopi
Starting 18 May 2017, we have modified the systematic corrections for the
new USNO VLBI series. The old corrections:
last.eops
bias slope
1.9743D-04 1.5524D-08 PM-x
-2.9818D-05 8.0924D-09 PM-y
2.2879D-06 -2.1219D-09 UT1-UTC
int_last.eopi
bias slope
1.6153D-06 -1.6274D-09 UT1-UTC
have been changed to:
last.eops
bias slope
1.0806D-04 2.9922D-08 PM-x
-2.4347D-05 -7.7376D-09 PM-y
5.3902D-07 -1.4864D-09 UT1-UTC
int_last.eopi
2.5113D-07 -9.4789D-10 UT1-UTC
**********************************************************************
This note dated 21 Sep 2017: Vol. XXX No. 038
**********************************************************************
Starting with the 21 Sep 2017 issues of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXX, No. 038 -- new
versions of the USNO VLBI solutions (usno2017b.eops and usno2017b.eopi) are
being used.
The new EOP series are:
ftp://rorf.usno.navy.mil/EOP/last.eops
ftp://rorf.usno.navy.mil/EOP/int_last.eopi
Starting 21 Sep 2017, we have modified the systematic corrections for the
new USNO VLBI series. The old corrections:
last.eops
bias slope
1.0806D-04 2.9922D-08 PM-x
-2.4347D-05 -7.7376D-09 PM-y
5.3902D-07 -1.4864D-09 UT1-UTC
int_last.eopi
bias slope
2.5113D-07 -9.4789D-10 UT1-UTC
have been changed to:
last.eops
bias slope
9.7190D-05 3.3667D-08 PM-x
-9.8235D-05 -1.0090D-08 PM-y
3.1725D-06 -2.7895D-10 UT1-UTC
int_last.eopi
8.9143D-06 -1.4893D-09 UT1-UTC
**********************************************************************
This note dated 29 Mar 2018: Vol. XXXI No. 013
**********************************************************************
As of Bulletin A Vol. XXXI, No. 013, on 29 March 2018, the IERS RS/PC solution
has been transitioned to be consistent with the 14 C04 EOP series for polar
motion, UT1-UTC, and celestial pole offsets. This change will result in a
jump of less than 0.1 mas in polar motion and 10 us in UT1-UTC. Small
adjustments were also made to celestial pole offsets from approximately
March 2017 to present in order to be more consistent with the 14 C04 solution.
The only users who need to be concerned with this change are those who need
EOP accuracy to better than 0.1 mas (~0.3 cm at the Earth's surface, ~1.2 cm
at GPS orbit).
New versions of the USNO VLBI solutions (usn2018a.eoxy and usn2018a.eopi) are
also being used.
The new EOP series are:
ftp://rorf.usno.navy.mil/EOP/last.eoxy
ftp://rorf.usno.navy.mil/EOP/int_last.eopi
**********************************************************************
This note dated 10 May 2018: Vol. XXXI No. 019
**********************************************************************
As of Bulletin A Vol. XXXI, No. 019, on 10 May 2018, we have updated the IAA VLBI
solution systematic corrections. The effect appears to be less than 0.1 mas in
polar motion and 10 us in UT1-UTC.
The old corrections:
bias slope
1.1441D-05-3.5846D-09 IAA VLBI T
have been changed to:
bias slope
-4.5585D-06 2.365D-09 IAA VLBI T
**********************************************************************
This note dated 17 May 2018: Vol. XXXI No. 020
**********************************************************************
As of Bulletin A Vol. XXXI No. 020, on 17 May 2018, the contri-
bution of the US Navy Fleet Numerical Meteorology and Oceanography
Center (FNMOC) to the Atmospheric Angular Momentum (AAM)
inputs has been upgraded to version 1.4.3eop of the Navy Global
Environmental Model (NAVGEM). It is anticipated that this
upgrade may somewhat improve the short term UT1-UTC predictions.
**********************************************************************
This note dated 16 August 2018: Vol. XXXI No. 033
**********************************************************************
As of Bulletin A Vol. XXXI No. 033, on 16 August 2018, the method for
identifying "duplicate" epochs (epochs of observations within 0.01 days) in
the Rapid Service / Prediction Center combination software has been modified.
This code adjustment appears to result in a change to polar motion of
~1 mas in the observed solution, and < 50 mas in the predicton values.
Changes to UT1-UTC appear to be negligible.
**********************************************************************
This note dated 23 Aug 2018: Vol. XXXI No. 034
**********************************************************************
As of Bulletin A Vol. XXXI, No. 034, on 23 August 2018
New versions of the USNO VLBI solutions (usn2018b.eoxy and usn2018b.eopi) are
also being used.
The new EOP series are:
ftp://rorf.usno.navy.mil/EOP/last.eoxy
ftp://rorf.usno.navy.mil/EOP/int_last.eopi
**********************************************************************
This note dated 11 Jul 2019: Vol. XXXII No. 026
**********************************************************************
The method of computing statistics for the second instance of the
IGS Final comparison in the file gpspol.asc during the last 30
days has been updated to use the more accurate smoothing cubic
spline used in the EOP combination.
**********************************************************************
This note dated 01 Aug 2019: Vol. XXXII No. 031
**********************************************************************
Starting with the 01 Aug 2019 issues of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXXII, No. 031 -- new
versions of the USNO VLBI solutions (usno2019c.eoxy and usno2019c.eopi) are
being used.
The new EOP series are:
ftp://rorf.usno.navy.mil/EOP/last.eoxy
ftp://rorf.usno.navy.mil/EOP/int_last.eopi
Starting 01 Aug 2019, we have modified the systematic corrections for the
new USNO VLBI series. The old corrections:
last.eoxy
bias slope
3.4061D-04 -6.7581D-09 PM-x
-2.0482D-04 -2.8804D-09 PM-y
2.5182D-06 1.1675D-10 UT1-UTC
int_last.eopi
bias slope
-3.8628D-06 2.1476D-09 UT1-UTC
have been changed to:
last.eoxy
bias slope
3.2165D-04 -3.7118D-09 PM-x
-2.6147D-04 3.5458D-09 PM-y
-8.2672D-06 1.3019D-09 UT1-UTC
int_last.eopi
-1.6565D-08 3.0549D-12 UT1-UTC
**********************************************************************
This note dated 29 Aug 2019: Vol. XXXII No. 035
**********************************************************************
Starting with the 29 Aug 2019 issues of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXXII, No. 035 -- new
versions of the GSFC VLBI solutions (gsfc2019a.eoxy and gsfc2019a.eopi) are
being used.
The process was actually begun on 22 Aug 2019; however, the complete change over
not implemented until the week of Aug 26, 2019. So, the first issue of the IERS
Bulletin A that has the complete change is Vol. XXXII, No. 035.
The new EOP series are:
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eops/gsf2019a.eops.gz
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eopi/gsf2019a.eopi.gz
The solution descriptions are:
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eops/gsf2019a.eops.txt
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eopi/gsf2019a.eopi.txt
gsf2016a.eopi
bias slope
4.7244D-06 1.2584D-09 UT1-UTC
gsf2016a.eoxy
bias slope
9.869D-05 -2.4263D-08 PM-x
-1.4648D-04 6.885D-09 PM-y
1.0998D-05 1.7285D-10 UT1-UTC
have been changed to:
gsf2019a.eopi
bias slope
3.5854D-07 1.1148D-09 UT1-UTC
gsf2019a.eoxy
bias slope
1.2862D-04 6.2445D-09 PM-x
-5.3656D-05 1.4629D-08 PM-y
7.6409D-06 4.7734D-10 UT1-UTC
In addition, there were small additional systematic corrections made to the
USNO 24hr and intensives series for UT1-UTC at the same time.
The updated systematic corrections for the USNO 24hr and series 2019c are:
usno2019c.eopi
bias slope
7.2747D-06-1.3259D-09 UT1-UTC
usno2019c.eoxy
bias slope
1.2654D-05-1.4765D-09 UT1-UTC
**********************************************************************
This note dated 16 Jan 2020: Vol. XXXIII No. 003
**********************************************************************
Starting with the 16 Jan 2020 issues of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXXIII, No. 003 -- new
versions of the GSFC VLBI solutions (gsfc2019d.eoxy and gsfc2019d.eopi) are
being used. The effect appears to be less than 0.1 mas in polar motion and
10 us in UT1-UTC.
The data are available at:
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eops/gsf2019d.eops.gz
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eopi/gsf2019d.eopi.gz
The solution descriptions are:
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eops/gsf2019d.eops.txt
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eopi/gsf2019d.eopi.txt
The old gsfc 2019a 24hr series corrections were:
gsf2019a.eoxy
bias slope
1.2862e-04 6.2445e-09 PM-x
-5.3656e-05 1.4629e-08 PM-y
7.6409e-06 4.7734e-10 UT1-UTC
The updated systematic corrections for the gsfc 24hr series 2019d are:
gsf2019d.eoxy
bias slope
1.5712e-03 -1.7982e-07 PM-x
-1.5673e-03 1.9554e-07 PM-y
9.7898e-06 -3.2679e-10 UT1-UTC
The new gsfc intensives series 201d corrections were updated to include
separate offset and slope for several 2 station baselines.
These are listed below, with the offset listed first and the slope
to the right (units are seconds and seconds/day, respectively):
[[KkWz_baseline]]
stations = KkWz
dut1 = 7.0004e-06, 1.0134e-09
[[IsWz_baseline]]
stations = IsWz
dut1 = -5.0696e-05, 8.7166e-09
[[MkWz_baseline]]
stations = MkWz
dut1 = -2.1509e-04, 3.231e-08
[[KkNy_baseline]]
stations = KkNy
dut1 = 7.0004e-06, 1.0134e-09
[[KkSv_baseline]]
stations = KkSv
dut1 = 7.0004e-06, 1.0134e-09
[[KkWn_baseline]]
stations = KkWn
dut1 = 7.0004e-06, 1.0134e-09
[[IsWn_baseline]]
stations = IsWn
dut1 = 7.0004e-06, 1.0134e-09
[[IsNy_baseline]]
stations = IsNy
dut1 = 7.0004e-06, 1.0134e-09
[[ShWz_baseline]]
stations = ShWz
dut1 = 7.0004e-06, 1.0134e-09
[[kseries]]
sess = k
dut1 = 7.0004e-06, 1.0134e-09
**********************************************************************
This note dated 30 Jan 2020: Vol. XXXIII No. 005
**********************************************************************
As of Bulletin A Vol. XXXIII, No. 005, 30 Jan 2020, we have
incorporated the new USNO VLBI solutions -- usno2020a.eoxy and
usno2020a.eopi. The effect appears to be less than 0.1 mas in
polar motion and 10 us in UT1-UTC.
The systematic corrections have been changed to:
last.eoxy
bias slope
7.8909e-05, -1.0238e-08 PM-x
-1.6252e-04, 2.1028e-08 PM-y
1.7879e-06, -1.3840e-09 UT1-UTC
int_last.eopi
[usno_vlbi_int]
[[KkWz_baseline]]
stations = KkWz
dut1 = 3.0671e-07, -1.306e-09
[[IsWz_baseline]]
stations = IsWz
# sess = q
dut1 = -3.3545e-05, 1.8428e-09
[[MkWz_baseline]]
stations = MkWz
dut1 = 7.1258e-05, -9.7036e-09
[[KkNy_baseline]]
stations = KkNy
dut1 = 3.0671e-07, -1.306e-09
[[KkSv_baseline]]
stations = KkSv
dut1 = 3.0671e-07, -1.306e-09
[[KkWn_baseline]]
stations = KkWn
dut1 = 3.0671e-07, -1.306e-09
[[IsWn_baseline]]
stations = IsWn
dut1 = 3.0671e-07, -1.306e-09
[[IsNy_baseline]]
stations = IsNy
dut1 = 3.0671e-07, -1.306e-09
[[ShWz_baseline]]
stations = ShWz
dut1 = 3.0671e-07, -1.306e-09
[[kseries]]
sess = k
dut1 = 3.0671e-07, -1.306e-09
UT1-UTC
**********************************************************************
This note dated 21 May 2020: Vol. XXXIII No. 021
**********************************************************************
Starting with the 21 May 2020 issues of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXXIII, No. 021 -- new
versions of the GSFC VLBI solutions (gsfc2020a.eoxy and gsfc2020a.eopi) are
being used. The effect appears to be less than 0.1 mas in polar motion and
10 us in UT1-UTC.
The data are available at:
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eops/gsf2020a.eops.gz
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eopi/gsf2020a.eopi.gz
The solution descriptions are:
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eops/gsf2020a.eops.txt
ftp://cddis.gsfc.nasa.gov/pub/vlbi/ivsproducts/eopi/gsf2020a.eopi.txt
The old gsfc 2019a 24hr series corrections were:
gsf2019d.eoxy
bias slope
1.5712e-03 -1.7982e-07 PM-x
-1.5673e-03 1.9554e-07 PM-y
9.7898e-06 -3.2679e-10 UT1-UTC
The updated systematic corrections for the gsfc 24hr series 2019d are:
gsf2020a.eoxy
bias slope
1.9032e-04 -1.3233e-08 PM-x
-7.0373e-05 1.1086e-08 PM-y
1.0817e-05 -5.3725e-10 UT1-UTC
The new gsfc intensives series 201d corrections were updated to include
separate offset and slope for several 2 station baselines.
These are listed below, with the offset listed first and the slope
to the right (units are seconds and seconds/day, respectively):
[gsfc_vlbi_int]
[[KkWz_baseline]]
stations = KkWz
dut1 = 6.1085e-06, -1.508e-10
[[IsWz_baseline]]
stations = IsWz
dut1 = -4.8431e-05, 7.4389e-09
[[MkWz_baseline]]
stations = MkWz
dut1 = 3.3975e-05, -4.7383e-09
[[MkWn_baseline]]
stations = MkWn
dut1 = 3.3975e-05, -4.7383e-09
[[KkNy_baseline]]
stations = KkNy
dut1 = 6.1085e-06, -1.508e-10
[[KkSv_baseline]]
stations = KkSv
dut1 = 6.1085e-06, -1.508e-10
[[KkWn_baseline]]
stations = KkWn
dut1 = 6.1085e-06, -1.508e-10
[[IsWn_baseline]]
stations = IsWn
dut1 = 6.1085e-06, -1.508e-10
[[IsNy_baseline]]
stations = IsNy
dut1 = 6.1085e-06, -1.508e-10
[[ShWz_baseline]]
stations = ShWz
dut1 = 6.1085e-06, -1.508e-10
[[kseries]]
sess = k
dut1 = 6.1085e-06, -1.508e-10
**********************************************************************
This note dated 28 May 2020: Vol. XXXIII No. 022
**********************************************************************
Starting with the 28 May 2020 issues of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXXIII, No. 022 -- new
versions of the USNO VLBI solutions (usno2020b.eoxy and usno2020b.eopi) are
being used. The effect appears to be less than 0.1 mas in polar motion and
10 us in UT1-UTC.
The previous 24-hr systematic corrects were updated on 28 May 2020 and listed previously.
The 24-hr systematic corrections have been changed to:
[usno_vlbi_24hr]
pmx = 7.8270e-05, -9.4407e-09
pmy = -1.7060e-04, 2.2565e-08
dut1 = 5.2371e-06, -1.3461e-09
The intensives systematic corrections have been changed to:
[usno_vlbi_int]
[[KkWz_baseline]]
stations = KkWz
dut1 = -1.9701e-08, -1.1615e-09
[[IsWz_baseline]]
stations = IsWz
# sess = q
dut1 = -4.4996e-05, 3.5953e-09
[[MkWz_baseline]]
stations = MkWz
dut1 = 3.4584e-05, -4.4857e-09
[[MkWn_baseline]]
stations = MkWn
dut1 = 1.2722e-04, -1.7588e-08
[[KkNy_baseline]]
stations = KkNy
dut1 = -1.9701e-08, -1.1615e-09
[[KkSv_baseline]]
stations = KkSv
dut1 = -1.9701e-08, -1.1615e-09
[[KkWn_baseline]]
stations = KkWn
dut1 = -1.9701e-08, -1.1615e-09
[[IsWn_baseline]]
stations = IsWn
dut1 = -1.9701e-08, -1.1615e-09
[[IsNy_baseline]]
stations = IsNy
dut1 = -1.9701e-08, -1.1615e-09
[[ShWz_baseline]]
stations = ShWz
dut1 = -1.9701e-08, -1.1615e-09
[[kseries]]
sess = k
**********************************************************************
This note dated 04 Feb 2021: Vol. XXXIV No. 005
**********************************************************************
Starting with the 04 Feb 2021 issues of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXXIV, No. 005 -- new
versions of the USNO VLBI solutions (usno2020d.eoxy and usno2020d.eopi) are
being used. The effect appears to be less than 0.1 mas in polar motion and
10 us in UT1-UTC.
The previous 24-hr systematic corrects were updated on 30 Jan 2020 and listed previously.
The 24-hr systematic corrections have been changed to:
[usno_vlbi_24hr]
pmx = -7.0974e-05, 1.3434e-08
pmy = -2.8944e-04, 4.0042e-08
dut1 = 1.3384e-05, -2.7091e-09
The intensives systematic corrections have been changed to:
[usno_vlbi_int]
[[KkWz_baseline]]
stations = KkWz
dut1 = -1.5583e-05, 1.9521e-09
[[IsWz_baseline]]
stations = IsWz
dut1 = 8.112e-05, -1.367e-08
[[MkWz_baseline]]
stations = MkWz
dut1 = -4.2024e-05, 6.6175e-09
[[MkWn_baseline]]
stations = MkWn
dut1 = 1.7583e-04, -2.4536e-08
[[KkNy_baseline]]
stations = KkNy
dut1 = -1.5583e-05, 1.9521e-09
[[KkSv_baseline]]
stations = KkSv
dut1 = -1.5583e-05, 1.9521e-09
[[KkWn_baseline]]
stations = KkWn
dut1 = -1.5583e-05, 1.9521e-09
[[IsWn_baseline]]
stations = IsWn
dut1 = 8.112e-05, -1.367e-08
[[IsNy_baseline]]
stations = IsNy
dut1 = -1.5583e-05, 1.9521e-09
[[ShWz_baseline]]
stations = ShWz
dut1 = -1.5583e-05, 1.9521e-09
[[kseries]]
sess = k
dut1 = -1.5583e-05, 1.9521e-09
**********************************************************************
This note dated 11 Feb 2021: Vol. XXXIV No. 006
**********************************************************************
Starting with the 11 Feb 2021 issues of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXXIV, No. 006 -- a new
version of the IVS VLBI solution (ivs20r1X.eops) is being used.
The effect appears to be less than 0.1 mas in polar motion and
10 us in UT1-UTC.
The previous 24-hr systematic corrects were updated several years ago when
the C04 was updated to the 14C04 series.
The 24-hr systematic corrections have been changed to:
[ivs_vlbi_24hr]
pmx = 1.1112e-04, -1.5674e-08
pmy = -9.6813e-05, 3.2792e-08
dut1 = 9.0842e-06, -1.0557e-09
**********************************************************************
This note dated 24 Jun 2021: Vol. XXXIV No. 025
**********************************************************************
Starting with the 24 Jun 2021 issues of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXXIV, No. 025 -- new
versions of the USNO VLBI solutions (usno2021b.eoxy and usno2021b.eopi) are
being used. The effect appears to be less than 0.1 mas in polar motion and
10 us in UT1-UTC.
The previous 24-hr systematic corrects were updated on 04 Feb 2021 and listed previously.
The 24-hr systematic corrections have been changed to:
[usno_vlbi_24hr]
pmx = -8.4424e-05, 1.5317e-08
pmy = -1.2523e-04, 1.4628e-08
dut1 = 1.5307e-05, -3.0120e-09
The intensives systematic corrections have been changed to:
[usno_vlbi_int]
[[KkWz_baseline]]
stations = KkWz
dut1 = -1.7079e-05, 2.0984e-09
[[IsWz_baseline]]
stations = IsWz
dut1 = 8.8357e-05, -1.4804e-08
[[MkWz_baseline]]
stations = MkWz
dut1 = -2.345e-04, 3.1523e-08
[[MkWn_baseline]]
stations = MkWn
dut1 = 2.751e-04, -3.8449e-08
[[KkNy_baseline]]
stations = KkNy
dut1 = -1.7079e-05, 2.0984e-09
[[KkSv_baseline]]
stations = KkSv
dut1 = -1.7079e-05, 2.0984e-09
[[KkWn_baseline]]
stations = KkWn
dut1 = -1.7079e-05, 2.0984e-09
[[IsWn_baseline]]
stations = IsWn
dut1 = 1.4729e-04, -2.3401e-08
[[IsNy_baseline]]
stations = IsNy
dut1 = -1.7079e-05, 2.0984e-09
[[ShWz_baseline]]
stations = ShWz
dut1 = -1.7079e-05, 2.0984e-09
[[kseries]]
sess = k
dut1 = -1.7079e-05, 2.0984e-09
**********************************************************************
This note dated 18 Nov 2021: Vol. XXXIV No. 046
**********************************************************************
Starting with the 18 Nov 2021 issues of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXXIV, No. 046 -- new
versions of the USNO VLBI solutions (usn2021c.eoxy and usn2021c.eopi) are
being used. The effect appears to be less than 0.1 mas in polar motion and
10 us in UT1-UTC.
The previous 24-hr systematic corrects were updated on 24 Jun 2021 and listed
previously.
The 24-hr systematic corrections have been changed to:
[usno_vlbi_24hr]
pmx = -1.2284e-04, 2.0956e-08
pmy = -1.983e-04, 2.4216e-08
dut1 = 3.2917e-05, -5.6083e-09
The intensives systematic corrections have been changed to:
[usno_vlbi_int]
[[KkWz_baseline]]
stations = KkWz
dut1 = -1.6214e-05, 1.633e-09
[[IsWz_baseline]]
stations = IsWz
dut1 = 6.038e-05, -1.0748e-08
[[MkWz_baseline]]
stations = MkWz
dut1 = 5.178e-06, 1.3799e-10
[[MkWn_baseline]]
stations = MkWn
dut1 = 1.6146e-04, -2.2317e-08
[[KkNy_baseline]]
stations = KkNy
dut1 = -1.6214e-05, 1.633e-09
[[KkSv_baseline]]
stations = KkSv
dut1 = -1.6214e-05, 1.633e-09
[[KkWn_baseline]]
stations = KkWn
dut1 = -1.6214e-05, 1.633e-09
[[IsWn_baseline]]
stations = IsWn
dut1 = 1.5779e-04, -2.4953e-08
[[IsNy_baseline]]
stations = IsNy
dut1 = -1.6214e-05, 1.633e-09
[[ShWz_baseline]]
stations = ShWz
dut1 = -1.6214e-05, 1.633e-09
[[kseries]]
sess = k
dut1 = -1.6214e-05, 1.633e-09
**********************************************************************
This note dated 23 Dec 2021: Vol. XXXIV No. 051
**********************************************************************
Starting with the 23 Nov 2021 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXXIV, No. 051 -- a
new version of the IAA VLBI solution (iaa2021a.eops) are being used. The
effect appears to be less than 0.1 mas in polar motion and 10 us in UT1-UTC.
The previous 24-hr systematic corrections were updated on 10 May 2018.
The 24-hr systematic corrections have been changed to:
[iaa_vlbi_24hr]
pmx = -3.924e-04, 5.3499e-08
pmy = 4.5894e-04, -6.3613e-08
dut1 = 6.0573e-05, -8.5269e-09
**********************************************************************
This note dated 7 Apr 2022: Vol. XXXV No. 014
**********************************************************************
Starting with the 7 Apr 2022 issues of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXXV, No. 014 -- new
versions of the USNO VLBI solutions (usn2022a.eoxy and usn2022a.eopi) are
being used. The effect appears to be less than 0.1 mas in polar motion and
10 us in UT1-UTC.
The previous 24-hr systematic corrects were updated on 18 Nov 2021 and listed
previously.
The 24-hr systematic corrections have been changed to:
[usno_vlbi_24hr]
pmx = -2.0974e-04, 3.3098e-08
pmy = -5.8028e-05, 2.5942e-09
dut1 = 3.2349e-05, -5.5844e-09
[usno_vlbi_int]
[[KkWz_baseline]]
stations = KkWz
dut1 = -5.8563e-06, -3.2551e-11
[[IsWz_baseline]]
stations = IsWz
dut1 = 8.114e-05, -1.2988e-08
[[MkWz_baseline]]
stations = MkWz
dut1 = 1.1181e-04, -1.4146e-08
[[MkWn_baseline]]
stations = MkWn
dut1 = 2.6262e-04, -3.6526e-08
[[KkNy_baseline]]
stations = KkNy
dut1 = -5.8563e-06, -3.2551e-11
[[KkSv_baseline]]
stations = KkSv
dut1 = -5.8563e-06, -3.2551e-11
[[KkWn_baseline]]
stations = KkWn
dut1 = -5.8563e-06, -3.2551e-11
[[IsWn_baseline]]
stations = IsWn
dut1 = 1.6796e-04, -2.5739e-08
[[IsNy_baseline]]
stations = IsNy
dut1 = -5.8563e-06, -3.2551e-11
[[ShWz_baseline]]
stations = ShWz
dut1 = -5.8563e-06, -3.2551e-11
[[kseries]]
sess = k
dut1 = -5.8563e-06, -3.2551e-11
**********************************************************************
This note dated 7 Jul 2022: Vol. XXXV No. 027
**********************************************************************
Starting with the 7 Jul 2022 issues of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXXV, No. 027 -- new
versions of the USNO VLBI solutions (usn2022b.eoxy and usn2022b.eopi) are
being used. The effect appears to be less than 0.1 mas in polar motion and
10 us in UT1-UTC.
The previous 24-hr systematic corrects were updated on 7 Apr 2022 and listed
previously.
The 24-hr systematic corrections have been changed to:
[usno_vlbi_24hr]
pmx = -9.4689e-05, 1.6291e-08
pmy = -7.548e-07, -6.5237e-09
dut1 = 9.327e-06, -2.8379e-09
The intensives systematic corrections have been changed to:
[usno_vlbi_int]
[[KkWz_baseline]]
stations = KkWz
dut1 = 2.7532e-05, -5.0546e-09
[[IsWz_baseline]]
stations = IsWz
dut1 = 8.9926e-05, -1.4289e-08
[[MkWz_baseline]]
stations = MkWz
dut1 = 8.6865e-05, -1.1304e-08
[[MkWn_baseline]]
stations = MkWn
dut1 = 2.7687e-04, -3.8846e-08
[[KkNy_baseline]]
stations = KkNy
dut1 = 2.7532e-05, -5.0546e-09
[[KkSv_baseline]]
stations = KkSv
dut1 = 2.7532e-05, -5.0546e-09
[[KkWn_baseline]]
stations = KkWn
dut1 = 2.7532e-05, -5.0546e-09
[[IsWn_baseline]]
stations = IsWn
dut1 = 1.6445e-04, -2.5338e-08
[[IsNy_baseline]]
stations = IsNy
dut1 = 2.7532e-05, -5.0546e-09
[[ShWz_baseline]]
stations = ShWz
dut1 = 2.7532e-05, -5.0546e-09
[[kseries]]
sess = k
dut1 = 2.7532e-05, -5.0546e-09
**********************************************************************
This note dated 13 Oct 2022: Vol. XXXV No. 041
**********************************************************************
Starting with the 13 Oct 2022 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXXV, No. 041 -- new
versions of the USNO VLBI solutions (usn2022c.eoxy and usn2022c.eopi) are
being used. The effect appears to be less than 0.1 mas in polar motion and
10 us in UT1-UTC.
The previous 24-hr systematic corrects were updated on 7 Jul 2022 and listed
previously.
The 24-hr systematic corrections have been changed to:
[usno_vlbi_24hr]
pmx = -1.83041e-04, 2.86564e-08
pmy = 5.03094e-04, -7.26558e-08
dut1 = 9.03097e-06, -2.85625e-09
The intensives systematic corrections have been changed to:
[usno_vlbi_int]
[[KkWz_baseline]]
stations = KkWz
dut1 = 5.39917e-05, -8.63223e-09
[[IsWz_baseline]]
stations = IsWz
dut1 = 8.88392e-05, -1.42889e-08
[[MkWz_baseline]]
stations = MkWz
dut1 = 8.89519e-05, -1.16179e-08
[[MkWn_baseline]]
stations = MkWn
dut1 = 4.15100e-04, -5.78358e-08
[[KkNy_baseline]]
stations = KkNy
dut1 = 5.39917e-05, -8.63223e-09
[[KkSv_baseline]]
stations = KkSv
dut1 = 5.39917e-05, -8.63223e-09
[[KkWn_baseline]]
stations = KkWn
dut1 = 5.39917e-05, -8.63223e-09
[[IsWn_baseline]]
stations = IsWn
dut1 = 1.42834e-04, -2.20554e-08
[[IsNy_baseline]]
stations = IsNy
dut1 = 5.39917e-05, -8.63223e-09
[[ShWz_baseline]]
stations = ShWz
dut1 = 5.39917e-05, -8.63223e-09
[[kseries]]
sess = k
dut1 = 5.39917e-05, -8.63223e-09
**********************************************************************
This note dated 05 Jan 2023: Vol. XXXVI No. 001
**********************************************************************
Starting with the 05 Jan 2023 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXXVI, No. 001 -- new
versions of the USNO VLBI solutions (usn2022d.eoxy and usn2022d.eopi) are
being used. The effect appears to be less than 0.1 mas in polar motion and
10 us in UT1-UTC.
The previous systematic corrections were updated on 13 Oct 2022 and listed
previously.
The 24-hr systematic corrections have been changed to:
[usno_vlbi_24hr]
pmx = -3.06848e-04, 4.33732e-08
pmy = 2.71048e-04, -4.18558e-08
dut1 = 3.03668e-05, -5.61656e-09
The intensives systematic corrections have been changed to:
[usno_vlbi_int]
[[KkWz_baseline]]
stations = KkWz
dut1 = 4.66458e-05, -7.80501e-09
[[IsWz_baseline]]
stations = IsWz
dut1 = 6.57072e-05, -1.07216e-08
[[MkWz_baseline]]
stations = MkWz
dut1 = 8.86947e-05, -1.17975e-08
[[MkWn_baseline]]
stations = MkWn
dut1 = 2.10480e-04, -2.92138e-08
[[KkNy_baseline]]
stations = KkNy
dut1 = 4.66458e-05, -7.80501e-09
[[KkSv_baseline]]
stations = KkSv
dut1 = 4.66458e-05, -7.80501e-09
[[KkWn_baseline]]
stations = KkWn
dut1 = 4.66458e-05, -7.80501e-09
[[IsWn_baseline]]
stations = IsWn
dut1 = 1.47179e-04, -2.23215e-08
[[IsNy_baseline]]
stations = IsNy
dut1 = 4.66458e-05, -7.80501e-09
[[ShWz_baseline]]
stations = ShWz
dut1 = 4.66458e-05, -7.80501e-09
**********************************************************************
This note dated 13 Apr 2023: Vol. XXXVI No. 015
**********************************************************************
Starting with the 13 Apr 2023 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXXVI, No. 015 -- new
versions of the GSFC VLBI solutions (gsf2023a.eoxy and gsf2023a.eopi) are
being used. The effect appears to be less than 0.1 mas in polar motion and
10 us in UT1-UTC.
The previous systematic corrections were updated on 21 May 2020 and listed
previously.
The 24-hr systematic corrections have been changed to:
pmx = -2.7365e-04, 4.0485e-08
pmy = 2.7951e-04, -3.6485e-08
dut1 = 3.5385e-05, -5.6688e-09
The intensives systematic corrections have been changed to:
[[KkWz_baseline]]
stations = KkWz
dut1 = 5.6167e-05, -8.6922e-09
[[IsWz_baseline]]
stations = IsWz
dut1 = 1.1756e-04, -1.7744e-08
[[MkWz_baseline]]
stations = MkWz
dut1 = 2.5436e-05, -5.0063e-09
[[MkWn_baseline]]
stations = MkWn
dut1 = 2.5436e-05, -5.0063e-09
[[KkNy_baseline]]
stations = KkNy
dut1 = 5.6167e-05, -8.6922e-09
[[KkSv_baseline]]
stations = KkSv
dut1 = 5.6167e-05, -8.6922e-09
[[KkWn_baseline]]
stations = KkWn
dut1 = 5.6167e-05, -8.6922e-09
[[IsWn_baseline]]
stations = IsWn
dut1 = 1.1756e-04, -1.7744e-08
[[IsNy_baseline]]
stations = IsNy
dut1 = 1.1756e-04, -1.7744e-08
[[ShWz_baseline]]
stations = ShWz
dut1 = 5.6167e-05, -8.6922e-09
[[kseries]]
sess = k
dut1 = 5.6167e-05, -8.6922e-09
**********************************************************************
This note dated 20 Apr 2023: Vol. XXXVI No. 016
**********************************************************************
Starting with the 20 Apr 2023 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXXVI, No. 016 -- a new
version of the IVS VLBI solution (ivs2023a.eoxy) is being used. The effect
appears to be less than 0.1 mas in polar motion and 10 us in UT1-UTC.
The previous systematic corrections were updated on 11 Feb 2021 and listed
previously.
[ivs_vlbi_combi]
pmx = -4.4384e-03, 5.3992e-07
pmy = -6.8841e-03, 8.1414e-07
dut1 = -1.0123e-05, 1.3967e-09
**********************************************************************
This note dated 27 Apr 2023: Vol. XXXVI No. 017
**********************************************************************
Starting with the 27 Apr 2023 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXXVI, No. 017 -- a new
version of the USNO VLBI solution (usn2023a.eoxy and usn2023a.eopi) is being
used. The effect appears to be less than 0.1 mas in polar motion and 10 us
in UT1-UTC.
The previous systematic corrections were updated on 5 Jan 2023 and listed
previously.
The 24-hr systematic corrections have been changed to:
pmx = -2.22663e-04, 3.06266e-08
pmy = 6.94327e-04, -9.46937e-08
dut1 = 9.25850e-07, -1.44618e-09
The intensives systematic corrections have been changed to
[[KkWz_baseline]]
stations = KkWz
dut1 = 4.01913e-05, -6.47911e-09
[[IsWz_baseline]]
stations = IsWz
dut1 = 3.99233e-05, -7.03631e-09
[[MkWz_baseline]]
stations = MkWz
dut1 = 7.05299e-05, -1.09100e-08
[[MkWn_baseline]]
stations = MkWn
dut1 = 2.04729e-04, -3.00909e-08
[[KkNy_baseline]]
stations = KkNy
dut1 = 4.01913e-05, -6.47911e-09
[[KkSv_baseline]]
stations = KkSv
dut1 = 4.01913e-05, -6.47911e-09
[[KkWn_baseline]]
stations = KkWn
dut1 = 4.01913e-05, -6.47911e-09
[[IsWn_baseline]]
stations = IsWn
dut1 = 1.30049e-04, -2.00253e-08
[[IsNy_baseline]]
stations = IsNy
dut1 = 4.01913e-05, -6.47911e-09
[[ShWz_baseline]]
stations = ShWz
dut1 = 4.01913e-05, -6.47911e-09
[[kseries]]
sess = k
dut1 = 4.01913e-05, -6.47911e-09
**********************************************************************
This note dated 29 Jun 2023: Vol. XXXVI No. 026
**********************************************************************
As of Bulletin A Vol. XXXVI, No. 029, on 29 June 2023, the IERS RS/PC solution
has been transitioned to be consistent with the 20 C04 EOP series for polar
motion, UT1-UTC, and celestial pole offsets. This change will result in a
difference of less than an RMS of 0.015 mas in polar motion and 15 us in
UT1-UTC. The only users who need to be concerned with this change are those
who need EOP accuracy to better than 0.1 mas (~0.3 cm at the Earth's surface,
~1.2 cm at GPS orbit).
**********************************************************************
This note dated 27 Jul 2023: Vol. XXXVI No. 030
**********************************************************************
Starting with the 27 Jul 2023 issue of IERS Bulletin A (Rapid Service/
Predictions of Earth Orientation information) -- Vol. XXXVI, No. 030 -- a new
version of the USNO VLBI solution (usn2023b.eoxy and usn2023b.eopi) is being
used. The effect appears to be less than 0.1 mas in polar motion and 10 us
in UT1-UTC.
The previous systematic corrections were updated on 27 Apr 2023 and listed
previously.
**********************************************************************
This note dated 22 Aug 2023:
**********************************************************************
Beginning with the 22 Aug 2023 release of IERS Rapid Service/
Predictions of
Earth Orientation products, a new version of the GSI solution (gsiint2d.eopi)
is being used. The effect appears to be less than 10 us in UT1-UTC. The
updated systematic corrections can be found in syscorr.txt.
The previous systematic corrections were updated on 29 Jun 2023 to align the
Rapid Service/Prediction products to 20C04.
**********************************************************************
This note dated 07 Dec 2023: Vol. XXXVI No. 049
**********************************************************************
Beginning with the 07 Dec 2023 release of IERS Rapid Service/
Predictions of Earth Orientation products, a new version of the
USNO solution (usn2023c.eopi and usn2023c.eoxy) is being used. The effect
appears to be less than 10 us in UT1-UTC. The updated systematic corrections
can be found in syscorr.txt.
The previous systematic corrections were updated on 27 Jul 2023.
**********************************************************************
This note dated 01 Feb 2024: Vol. XXXVII No. 005
**********************************************************************
As of Bulletin A Vol. XXXVII, No. 005, on 1 February 2024, the systematic
corrections for IGS Finals, Rapids, and Ultra Rapids polar motion values were
re-calculated to include a full year of data aligned to IGS20 (the IGS
realization of ITRF2020).
The previous systematic corrections for IGS polar motion were updated on
29 June 2023 along with the 20 C04 EOP transition.
**********************************************************************
This note dated 14 Mar 2024: Vol. XXXVII No. 011
**********************************************************************
As of Bulletin A Vol. XXXVII, No. 011, on 14 March 2024, the systematic
corrections for IVS-combi 24-hr VLBI data were re-calculated to improve fit.
The effect appears to be less than 0.1 mas in polar motion and 10 us in
UT1-UTC.
The previous systematic corrections for IVS-combi were updated on 29 June 2023
along with the 20 C04 EOP transition.
**********************************************************************
This note dated 28 Mar 2024: Vol. XXXVII No. 013
**********************************************************************
Beginning with the 28 Mar 2024 release of IERS Rapid Service/
Predictions of Earth Orientation products, a new version of the
ILRSA solution (ilrsa.eop.{YY}{MM}{DD}.v180.snx), aligned to ITRF2020, is being
used. The effect appears to be less than 0.1 mas in polar motion. The updated
systematic corrections can be found in iers.new.
The previous systematic corrections for ILRSA were updated on 29 June 2023
along with the 20 C04 EOP transition.
**********************************************************************
This note dated 07 Jun 2024:
**********************************************************************
Beginning with the 07 June 2024 release of IERS Rapid Service/
Predictions of Earth Orientation products, a new version of the
USNO solution (usn2024a.eopi and usn2024a.eoxy) is being used. The effect
appears to be less than 0.1 mas in polar motion and 10 us in UT1-UTC. The
updated systematic corrections can be found in syscorr.txt.
The previous systematic corrections for USNO VLBI
were updated on 07 Dec 2023.
**********************************************************************
This note dated 01 Aug 2024:
**********************************************************************
Beginning with the 01 Aug 2024 release of IERS Rapid Service/
Predictions of Earth Orientation products, the systematic corrections for GSI
VLBI data and IAA 24hr VLBI data were re-calculated to improve fit.
The effect appears to be less than 0.1 mas in polar motion and 10 us in
UT1-UTC. The updated systematic corrections can be found in syscorr.txt and
generate_cpo.ini.
The previous systematic corrections for GSI and IAA VLBI data were updated on
22 Aug 2023 and 29 Jun 2023, respectively.
**********************************************************************
This note dated 17 Sep 2024:
**********************************************************************
Beginning with the 17 Sep 2024 release of IERS Rapid Service/ Predictions of
Earth Orientation products, updates to systematic corrections for the GSFC
VLBI Intensives (gsf2023a.eopi) have been applied to the combination. The
effect appears to be less than 10 us in UT1-UTC. The updated systematic
corrections can be found in syscorr.txt.
**********************************************************************
This note dated 19 Sep 2024:
**********************************************************************
Beginning with the 19 Sep 2024 release of IERS Rapid Service/ Predictions of
Earth Orientation products, updates to systematic corrections for the GSI
VLBI Intensives (gsiint2d.eopi) have been applied to the combination. The
effect appears to be less than 10 us in UT1-UTC. The updated systematic
corrections can be found in syscorr.txt.
**********************************************************************
This note dated 23 Jan 2025:
**********************************************************************
Beginning with the 23 Jan 2025 release of IERS Rapid Service/
Predictions of Earth Orientation products, a new version of the
USNO solution (usn2024b.eopi and usn2024b.eoxy) is being used. The effect
appears to be less than 0.1 mas in polar motion and 10 us in UT1-UTC. The
updated systematic corrections can be found in syscorr.txt.
The previous systematic corrections for USNO VLBI
were updated on 07 June 2024.
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Last updated 23 Jan 2025