I dropped an email off to the ESA helpdesk asking them about my mysterious satellite “39”, the following is the reply I received:

Dear Mr. Ronan,

thank you very much for contacting the EGNOS/ESTB Helpdesk . Your question has been recorded as Call nr. 01181.
Please note the following information.

The EGNOS satellites constellation includes the �ESA satellite ARTEMIS ( PRN 124 labelled on your Garmin unit �with the number 37 ) , the satellite AOR-E (PRN120 – number 33 on garmin units ) and the satellite IOR-W (PRN126 – number 39 on Garmin ). The three satellites have already been connected to the EGNOS computing platform and are currently being used for assembly , integration and validation tests of the system .
The signal currently broadcasted by the EGNOS satellites is in this phase for
testing purposes and can only be processed by profesional receivers.

EGNOS start of operations is today planned January/Feb 2005, this very much depends on the result of some specific tests which are planned in November December 2005. �Until end 2004, the system will undergo final tests to formally pronounce its qualification at an Operational Readiness Review (ORR). The EGNOS system will then be declared available for non safety critical applications in 2005 and will then undergo operational qualification activities towards its availability for safety of life services in 2006.

For additional information on EGNOS please visit our EGNOS for Professionals WebSite

At present and until EGNOS becomes operational �you may use the experimental signals broadcast by the ESTB ( the EGNOS System Test Bed which is an experimental version of EGNOS running since 2000). � The signals are broadcast through the satellite Inmarsat IOR (PRN131 number 44 on Garmin ) and available via SISNET . Coverage of the satellite IOR is available at (depending on the location in Europe like in the case of �north/east of England you might not
track the IOR signal ). ESTB SIS real time information is available at

Due to the experimental nature of the ESTB , the signals are broadcast without any guarantee of service as it is stated in the disclaimer available at: For internal testing it is therefore possible that some signal interruption may occur without giving notice in advance.

Additional information on the ESTB is available at our ESTB Web Site at

For further information on ESTB/EGNOS please don’t hesitate to contact us at the EGNOS Helpdesk.
Please note that our new e-mail address for the EGNOS Helpdesk is

Best Regards
EGNOS Helpdesk
European Space Agency

A fairly comprehensive answer. It should be a very useful service when it does go live. Now I’d better get back to work!