[IGSMAIL-3229]: IGP Products / Closing date

[Weber Robert]

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IGS Electronic Mail      12 Mar 06:12:15 PST 2001      Message Number 3229
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Author:  AC Coordinator /AIUB/CODE

Dear IGS colleagues,

as announced several times within the last months the generation of IGP 
products (IGS Predicted Orbits) will be discontinued very soon.
It has been decided to stop this series at the end of the current week. 

     This implies that the last IGP submission will be
                      IGP11056 
              (Satuday 17 March, MJD 51985)


Users are kindly asked to switch to the Ultra Rapid Products (IGU's)
which are official IGS products since GPS week 1052. The IGU products
are an orbit file (.sp3), an Earth Rotation file (IGS/IERS format), and
a combination summary file. The IGU products contain 48 hours orbits.
The first 24 hours are based on actual observations of the IGS network.
The second 24 hours contain a predicted orbit. The orbit should be 
continous at the boundary between the real and the predicted part.

IGU orbits are generated twice a day at 03.00 and 15.00 UTC and have a time 
lag (time after the last observation used) of 3 hours. Recent comparisions
have shown an orbit quality of about 15-20 cm (median) and therefore 
a remarkable improvement compared to the IGP products.

For additional information please have a look at IGSMail 3088 or at the
IGS Central Bureau Information System Web-site (Data and Products Page/
IGS Product Availability)

If you have any further questions regarding this or any of the other
IGS products please do not hesitate to contact me.

best regards


  Robert Weber
  IGS Analysis Center Coordinator
  (rweber at luna.tuwien.ac.at)


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Robert Weber                           Tel:    ++43-1-58801-12865               
Department of Advanced Geodesy         Fax:    ++43-1-58801-12896              
University of Technology, Vienna       E-Mail: rweber at luna.tuwien.ac.at
Gusshausstrasse 27-29                          robert.weber at aiub.unibe.ch
A-1040 Vienna, Austria                         
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