[IGSMAIL-6077]: Update: igs05.atx with SVN35/PRN25 changes

[Robert Khachikyan]

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IGS Electronic Mail      12 Feb 13:34:11 PST 2010      Message Number 6077
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Author: Ralf Schmid and Robert Khachikyan

Dear IGS colleagues!

The absolute IGS antenna correction file (igs05_wwww.atx) has been 
updated. The new release is called 'igs05_1570.atx'. It contains the 
following changes:

1) A decommission date for the following satellite has been added:

G25 (G025): 8 February 2010

"GPS satellite SVN25/PRN25, which was decommissioned from active service 
and removed from broadcast almanacs on 18 December 2009, stopped 
transmitting valid L1/L2 signals on 8 February 2010. Although the 
satellite had been set unhealthy, it was still being tracked by stations 
of the International GNSS Service."
https://listserv.unb.ca/cgi-bin/wa?A2=ind1002&L=CANSPACE&T=0&F=&S=&P=10446

2) According to 'NANU 2010024' the following satellite has been added:

G25 (G035)

NOTICE ADVISORY TO NAVSTAR USERS (NANU) 2010024 NANU TYPE: GENERAL
*** GENERAL MESSAGE TO ALL GPS USERS ***
ON APPROXIMATELY 11 FEB 10 SVN35 WILL RESUME TRANSMITTING L-BAND 
UTILIZING PRN25. AT L-BAND ACTIVATION, SVN35/PRN25 WILL BE UNUSABLE 
UNTIL FURTHER NOTICE. ADDITIONALLY, NO BROADCAST ALMANACS WILL INCLUDE 
SVN35/PRN25.
FUTURE NANUS WILL INFORM USERS OF ANY CHANGES TO THE ABOVE-STATED STATUS.
*** GENERAL MESSAGE TO ALL GPS USERS ***
http://www.navcen.uscg.gov/archives/GPS/2010/NANUS/2010024.nnu

The updated antenna correction model is available at
ftp://igs.org/pub/station/general/igs05_1570.atx
or
ftp://igs.org/pub/station/general/igs05.atx

With best regards,
Ralf Schmid and Robert Khachikyan
on behalf of the IGS Antenna Working Group