Satellite positioning has already become a standard means of navigating on the high seas. In the near future, its use will spread to land and air. If satellite radionavigation signals were switched off tomorrow, many ships’ crews would be hard pressed to revert to traditional navigation methods using almanacs and sextants.
|The Earth & Space Expo|
“Satellite navigation users in Europe today have no alternative other than to use American GPS or Russian GLONASS satellite signals,” explained ESA’s Giulio Barbolani de Montauto. “Yet the military operators of both systems give no guarantee of maintaining uninterrupted service.”
Galileo will give Europe its own worldwide system for satellite radionavigation and positioning, providing a highly accurate, guaranteed service under civilian control. It will eliminate Europe’s dependence on other systems.
The appliance of space science
Galileo will offer everybody everywhere satellite positioning services with guaranteed reliability. Individuals, companies and administrations will all be able to benefit, whether on the roads, railways, in the skies or at sea.
The system has applications in numerous sectors including road, rail and air transport; mobile telephony; finance and insurance; and civil engineering. Its unprecedented accuracy could even lead to the development of navigation systems for blind people.
By 2020, the global satellite positioning market is set to reach some €275 billion a year, and Galileo will position Europe as the global leader. “Unlike its competitors, Galileo has been designed specifically for civilian and commercial use,” explained Nils Weller of the European Commission. “But its applications go beyond the commercial. It can be used to help carry out humanitarian operations, conduct search and rescue missions, monitor the environment and underwrite the safety of air travel.”
Galileo is also a good example of international co-operation, and emerging space powers such as China are closely involved in the project.
The fully deployed Galileo system will consist of 30 satellites, positioned in three medium-Earth orbits. Once these are in place, Galileo navigation signals will provide good coverage even in the polar regions.
The first experimental satellite, part of the so-called Galileo System Test Bed (GSTB) will be launched in the second half of 2005. Up to four operational satellites will be launched in 2005-2006 to validate the basic Galileo space and related ground segment. By the end of 2008, the entire system should be up and running.
Once operational, users will be able to take a position with the same receiver from any of the satellites in any combination. By offering dual frequencies as standard, Galileo will deliver real-time positioning accuracy down to a single metre, which is unprecedented for a publicly available system.
It will also guarantee availability of the service under all but the most extreme circumstances, and will inform users within seconds of a failure of any satellite. This will make it suitable for applications where safety is crucial, such as running trains, guiding cars and landing aircraft.
The patron saint of European astronomy
The seminar took place exactly 441 years after the birth of the famous Italian astronomer, Galileo Galilei. Born in Pisa on 15 February 1564. But Galileo is best known for his achievement in astronomy, though he also found time to invent the pendulum clock, develop a motion theory that showed all objects travelled at the same speed in a vacuum, and design a mechanical pump.
He is widely credited with inventing the telescope, even though he modelled his version on earlier instruments produced in other parts of Europe, and the Arabs had crude prototypes as early as the Abbasid caliphate (750-1258AD).
However, Galileo’s telescope was the most powerful to date and, with it, he discovered four of Jupiter’s moon, observed a supernova, verified the phases of Venus and discovered sunspots. He also verified Nicholas Copernicus’ controversial theory that the Earth and the planets revolved around the sun – a heresy for which he spent the rest of his life under house arrest.