A NEW space race kicked off last week as the European Space Agency finally decided to press ahead with its controversial plan to launch a network of navigation satellites to rival America鈥檚 Global Positioning System.
Unlike the military-run GPS, Europe鈥檚 Galileo system will be a civil venture, funded by the member states of the European Union and the European Space Agency (ESA). The system鈥檚 designers claim that by 2008, when 30 Galileo satellites are expected to be in orbit, Galileo will provide more accurate and more reliable navigational information than GPS.
Galileo will also offer additional features such as the first two-way global channel for emergency search and rescue communications. People using Galileo receivers will be able to send a Mayday, which automatically includes their location, to a central body that will then alert rescue authorities. And by using ultra-wide-band transmission frequencies, Galileo鈥檚 signals may even be able to penetrate buildings 鈥� something GPS cannot do.
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Even GPS advocates agree that Galileo may surpass GPS. 鈥淓urope will be years ahead of the kinds of capabilities that the US wants for GPS,鈥� says Keith McDonald, ex-director of the Department of Defense unit that set up the original 28-satellite GPS network. He is now technical director of GPS equipment supplier Navtech, based in Alexandria, Virginia.
Today鈥檚 28 GPS satellites are ageing and need to be replaced 鈥� 18 of them are either operating past their intended lifespan or malfunctioning. 鈥淭he satellites are lasting far longer than anyone thought they would,鈥� says McDonald. The Department of Defense plans to launch a fleet of enhanced satellites, called GPS III, but the first launch is not likely to happen until several years after Galileo is fully operational, meaning Galileo could undermine the tactical advantage GPS has afforded the US military.
The Pentagon is especially keen to modernise its GPS fleet following the war in Iraq. James Roche, the US Air Force Secretary, described Iraqi attempts to jam GPS-guided missiles as 鈥渢he first shots of space warfare鈥�. Ironically, the jammers were destroyed by GPS-guided weapons.
But the Pentagon opposes the Galileo network, citing the potential for interference with GPS signals. ESA dismisses the claim, because it views Galileo and GPS as complementary. It argues that Galileo will merely double the world鈥檚 positioning resources 鈥� since Galileo receivers will also receive GPS signals, making positioning even more accurate. Many users, particularly in aviation, want two systems, says Ian Munro of the British National Space Centre. Increased accuracy spells increased safety, he says.
Further transatlantic friction is expected. At the moment the US can selectively degrade the GPS signal available for civilian use, while maintaining an accurate signal for its own forces. But Galileo could undermine this by providing anyone, including US foes, with navigation capabilities previously matched only by the US military.