PARIS — Germany’s five SAR-Lupe radar reconnaissance satellites in 2009 faced more than 800 close encounters with orbital junk or other operating satellites, including 32 passes at less than one kilometer from another SAR-Lupe spacecraft and one that required a collision-avoidance maneuver, the head of the new German Space Situational Awareness Center (GSSAC) said.
Controllers of France’s Helios optical reconnaissance spacecraft, which operate in a different orbit, also were obliged to perform an avoidance maneuver in 2009 following an imminent-collision warning by the U.S. Space Surveillance Network, a French government official said.
The vulnerability of SAR-Lupe is one reason why the German army created the space-surveillance unit in Uedem, a facility that is expected to be expanded in the next three years as Germany and other nations in Europe create their own space-monitoring capability.
Speaking at the Milspace 2010 conference organized by the SMi Group here April 20, Col. Harald Borst, GSSAC’s director, said German authorities are becoming concerned that even small, relatively poor nations are now able to afford their own satellites, making space-traffic management, particularly in low Earth orbit, an increasing necessity.
The five SAR-Lupe satellites fly in three orbital planes in near-polar orbits at about 500 kilometers in altitude.
Germany’s defense forces, in a rare move, have invested cash in a European Space Agency-led program to design a European space surveillance system starting with ground-based radars already existing in Germany and France.
In parallel, Germany in 2009 inaugurated the GSSAC facility, which Borst said should increase in size to a permanent staff of 15 in 2011 from today’s three-person team.
Germany and France in 2009 carried out an initial series of coordination exercises called TIGRA using the existing German TIRA tracking radar and the French Graves surveillance radar. The Graves system is used for initial information about an object flying overhead. This data is then sent to Germany for analysis by the TIRA radar, which is able to zoom in to identify at least some large low-orbiting objects.
Borst said he regretted that the NATO alliance “is lagging a little behind” in seizing the space-surveillance initiative, as it has generally in the use of space by alliance members. He said the GSSAC data, which relies heavily on data from the U.S. Air Force Space Surveillance Network, would be made available to international bodies.
The U.S. data formed the basis of the assessments by the German Aerospace Center, DLR, in 2009 that caused one of the SAR-Lupe satellites to be moved to avoid a collision.
Similarly, U.S. authorities informed the French Defense Ministry in August 2009 that a Helios optical reconnaissance satellite, orbiting in near-polar orbit at 700 kilometers in altitude, was facing a collision.
Helios flight controllers at the French space agency, CNES, had not seen the danger in looking at the less-accurate U.S. Space Surveillance Network data published on the Internet, but reacted to the U.S. warning by moving the Helios satellite’s orbit, CNES President Yannick d’Escatha said.
On a second occasion less than two weeks later, CNES Helios controllers read the available data and feared that a fresh collision-avoidance maneuver would be required. They asked the U.S. Air Force for confirmation and were assured that the object would come no closer than 1.5 kilometers from Helios. An avoidance maneuver, which uses precious satellite fuel, was avoided.
On this second occasion, CNES also asked German authorities to deploy the TIRA radar to assess the situation, d’Escatha said.
U.S. and European authorities have begun to discuss how Europe’s fledgling space-surveillance effort might be used with the existing U.S. system.
In addition to the 18-nation European Space Agency (), a civil agency that is increasingly interested in dual-use space systems, the European Defence Agency (EDA) is also tackling space situational awareness. European Union defense agencies recently submitted to EDA a list of requirements for a military space-surveillance network, according to Rodolphe Paris, the defense agency’s project manager for satellite telecommunications, space situational awareness and radio frequency.
The military requirements were adopted March 26 by the European Defence Agency’s Steering Board.
Addressing the Milspace conference here, Paris said one of the military specifications of a future European space-surveillance system is that it reduce the likelihood of a collision with a European military satellite in low Earth orbit by 90 percent.
The European Defence Agency and ESA are scheduled to begin discussions of how a dual civil-military space-surveillance system should be created, and the rules under which it will operate.
Paris said European defense authorities are promoting the idea that any imaging of in-orbit objects should be “a 100 percent military” function, and that “European Union military representation at all levels” of the future system also be required.
Paris said the fact that European defense authorities have become fully involved with the future space-surveillance system has made it easier to develop a trans-Atlantic dialogue on future cooperation.