By Helen Briggs
BBC News science reporter
A UK-built satellite set to be launched in late December carries a tribute to a young British space engineer who died in the Boxing Day tsunami.
Giove-A will test important new technologies
Tom Fairbairn, who was 25, worked on Giove-A, the test mission for Europe's satellite-navigation system, Galileo.
The spacecraft is due to lift off on 28 December aboard a Russian Soyuz rocket from Baikonur in Kazakhstan.
Giove-A will demonstrate some of the new sat-nav system's key technologies, such as atomic clocks.
The mission will pave the way for the full Galileo constellation of 30 satellites, which will work alongside the US-owned Global Positioning System (GPS).
An important difference between the two is that the European network will be a civilian-run service - not a military one.
WHAT IS GALILEO?
Europe's own global satellite navigation system
Will work alongside US GPS and Russian Glonass systems
Promises real-time positioning down to under a metre
Guaranteed under all but most extreme circumstances
Suitable for safety-critical systems - can run trains, guide cars and land planes
Giove-A was built in Guildford, Surrey, by Surrey Satellite Technology Limited (SSTL), a company with about 200 employees that has become a world leader in producing small satellites.
Tom Fairbairn, who worked on the satellite's structural design team, died with his parents while on holiday at Khao Lak in Thailand last year.
"There is a plaque on the side [of the Giove-A satellite] and we would like to dedicate it to him," said Philip Davies of SSTL.
Giove-A and its "sister" satellite, Giove-B, set for launch in 2006, will broadcast the first Galileo signals from space.
The pair make up the test-bed mission that will demonstrate the Galileo potential.
"Giove-A is a test satellite, it's not going to be part of the final system," said Dr Colin Hicks, director-general of the British National Space Centre, which along with the UK's Department of Transport, has invested over 136m euros (£92m) in the project to date.
"We have designed everything believing it will work and now this is the first time we are going to test in orbit the technology that will be put into the Galileo system when eventually we launch 30 satellites."
The UK government is one of four big contributors to Galileo, alongside Germany, France and Italy.
"GPS is provided by the United States for its own purposes and it gives no guarantees to the world that it will continue to be there," Colin Hicks said.
THE GALILEO FUTURE
Expected to be more than 400 million sat-nav users by 2015
European aerospace and electronics firms say it will create more than 100,000 jobs
Rescue services will be able to pinpoint the exact location of a car driver's accident
System will allow someone to find their way in an unfamiliar city using their mobile phone
It will deliver a system that will make national road-pricing a practical possibility
"Galileo is a civil system provided by the European Union and the European Space Agency which will be there to give guaranteed availability of navigation systems to a higher degree of accuracy than GPS."
The launch of the test mission will allow Europe to start using its allocated Galileo frequencies.
"There will be a Galileo signal coming from space and people can start to develop Galileo receiving equipment," said Richard Peckham, chair of the satellite-navigation sub-committee for the trade association of the British space industry (UKISC).
Giove-A's signal will be fed into Egnos, an overlay system which can be used in Europe to improve the accuracy of GPS, but the Galileo service proper will not start to come online until 2009, when 12 satellites will be in place.
By the end of 2010, all 30 spacecraft in the Galileo constellation should have been deployed.
The whole system is costing more than 3bn euros (£2bn; $3.5bn) of public and private money and is being driven in its early phases by the European Commission and the European Space Agency.