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| Author | Topic: GALILEO GNSS Satellite Launch Gone Bad |
| jimh |
The website of NATURE.COM has an interesting article on the rather unfortunate problems of the recent launch of the first two fully operational capability (FOC) satellites for the GALILEO global satellite navigation system by the European Space Agency (ESA). The launch took place on August 22, 2014 from Kourou, French Guiana, using a Russian Soyuz-Fregat rocket. The orbital geometry of the satellites produced by the launch is quite far from the intended orbits, with the result that the satellites are of no practical value as part of the navigation system, even though they are operating normally. For more details see http://www.nature.com/news/ wayward-galileo-satellites-could-still-aid-scientists-1.15843 In their present orbits, the two GALILEO FOC satellites travel through the Van Allen Radiation Belt, and continued exposure to this radiation could be harmful to the satellite's electronics. This is reported in GPSWORLD at http://gpsworld.com/ galileo-provides-update-on-foc-anomaly-glonass-a-no-show/ I have not see a quoted figure from ESA for the cost of these satellites and their launch. The total project cost for GALILEO has been budgeted at $8.2-billion-USD. Figuring there would be 30 satellites, that suggest a per-satellite cost of about $273-million-USD. On that basis, the failure to attain a useful orbit has cost ESA about $546-million-USD. Studies are underway to determine the cause of the orbital problem and to determine if there exists any practical method to move the satellites into new orbits. |
| jimh |
Conspiracy theorists are suggesting some rather sinister reasons for the failure of the GALILEO FOC satellites to reach their intended orbits. See http://gpsworld.com/galileo-conspiracy-theory-and-flying-for-gps/ for details. |
| jimh |
News about the GALILEO global navigation satellite system seems to be trending downward. In July it was reported that one of the four in-orbit validation (IOV) satellites has suffered a "catastrophic power failure" and has been shut down. For more see http://gpsworld.com/trouble-aboard-galileo-satellite/ The loss of this IOV satellite and the orbital problems of the two fully operational capability (FOC) satellites in August have combined to be a significant setback for the $8.2-billion-USD project. |
| jimh |
There has been some good news for GALILEO. First, the cause of the orbital anomaly has been determined. It wasn't anything nefarious; an error in routing of some hoses or lines in the rocket caused temporary freezing of the propellent, and this resulted in less thrust during an important maneuver. This design error in the rocket is being corrected and should not affect future launches. Next, the orbit of the GALILEO-5 satellite has been improved by a series of orbital maneuvers, and the satellite is now in an orbit with a higher (better) perigee (lowest orbital altitude), getting it out of the Van Allen radiation belt (that it was passing through in its old orbit). Finally, navigation signals have been received by users at various locations from GALILEO-5. For more see: http://gpsworld.com/ the-system-fregat-design-ambiguity-steered-galileo-wrong/ http://gpsworld.com/orbit-of-one-wayward-galileo-satellite-raised/ http://gpsworld.com/first-nav-signal-from-galileo-5-received/ This is good news to all GNSS users. In the future it is anticipated that consumer grade GNSS receivers will be able to utilize GALILEO satellites. Presently, many marine GNSS receivers only receive GPS NAVSTAR satellites. |
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