The System: Compass Awry

August 1, 2009  - By

Compass Awry

One of the satellites in the Chinese domestic satellite navigation system, Beidou, is no longer in geostationary orbit and appears to have been abandoned.

According to information from the U.S. Space Command, the orbit of Beidou 1D was raised by around 130 kilometers on February 18, 2009. This may have been an attempt to place the satellite in a graveyard or disposal orbit. Such a maneuver is carried out by spacecraft operators when a satellite reaches the end of its life due to a malfunction or some other reason. However, the recommended boost height for geostationary satellites is about 300 kilometers, where a satellite is above the zone used to reposition active geostationary satellites and also provides a buffer for natural orbit variations due to solar radiation pressure and other causes. Beidou 1D may not have had sufficient propellant to reach desired orbit height.

In its current orbit, Beidou 1D is drifting westward at a rate of about 4.5 degrees per day and has already completed one circuit of the Earth. On July 17, it was positioned just west of the Greenwich meridian.

China launched Beidou 1D in February 2007; according to the Xinhua news agency at the time, the satellite was to serve as a backup to the three satellites already in orbit, perhaps replacing the first Beidou satellite, Beidou 1A, when necessary. Subsequent reports did indicate that Beidou 1A appeared to have malfunctioned.

It is not known what kind of malfunction Beidou 1D suffered or whether its signals have been switched off. Accurate detailed information about the current status of the Beidou domestic system is difficult to obtain.

China has plans to improve its domestic navigation system and to develop a global system known as Beidou 2 or Compass. Its first medium Earth orbit satellite, Beidou M1, was launched on April 13, 2007, followed by a geostationary satellite, Beidou G2, on April 14, 2009.

— Richard Langley

Galileo, Too, Has Accounting Problems

The European Union’s Galileo program has been ill-prepared and badly managed, according to a report by the European Court of Auditors released on June 29. These defects have set back development by five years, it believes.

The report also criticizes the Union’s 27 individual member states for counterproductive promotion of their respective national aerospace industries. The auditors conclude that the original public-private partnership plan was “inadequately prepared and conceived” and “unrealistic.”

The European Commission (EC) “must considerably strengthen its management,” advice the EC has evidently taken to heart. For the last year, contract negotiations by the European Space Agency (ESA) have taken place under the watchful eye of an EC program manager.

Contracts. On June 15, ESA signed contracts for the procurement of so-called long-lead items required for the construction of the constellation with Astrium GmbH and OHB Systems, the latter a German company and the former a German-French partnership with British involvement. Both Astrium (€7 million) and OHB (€10 million) contracts relate to parts for equipment of the satellite platforms and navigation payloads. Award of the satellite contracts themselves is planned to take place by the end of 2009.

ESA and Arianespace contracted for launch of the first four operational Galileo satellites on two Soyuz launch vehicles from Europe’s Spaceport in French Guiana. The four IOV satellites will be placed in orbit by end of 2010.

Conversations at the Paris Air Show seemed to indicate that ESA and the EC may divide the satellite construction contract into two stages to permit a later modification of the design, and that they may also divide the first satellite contract between the two bidders, Astrium and OHB, as an insurance policy to reduce the possibility of further development delays, and as a boon to design flexibility.

The Astrium CEO sharply criticized this option, saying it would increase overall program cost. The OHB CEO seemed more sanguine, lauding ESA’s move as likely to maintain a competitive environment.

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GPS World staff

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