By Brian Wheeler and Ed Challes
Britain could be on the verge of a belated re-entry into the space race, with the launch of a review into whether it should train astronauts to take part in future international exploration.
Galileo could be operational by 2013
Nasa is also due to give its formal backing to a British-led £100m unmanned mission to the Moon.
These are clearly exciting times for Britain's space industry - which has suffered in the past from a lack of government investment and political neglect.
The UK missed out on the boom in satellite launches when it cancelled its own rocket programme in the early 1970 but Britain has since become a world leader in the manufacture of satellites.
Science Minister Ian Pearson says space is currently worth £7bn to the UK economy and the sector is growing faster even than China's space industry.
But while ministers turn their gaze to the stars - and dream of Britons venturing to other planets - there is one long-running space saga which still has the power to bring them back down to earth with a bump.
Galileo - Europe's planned rival to America's Global Positioning System (GPS) - has been beset by a series of cost-overruns and technical delays since it was first proposed at the end of the last century.
The first of about 30 Galileo satellites should have been in operation this year, 26,000km above the planet - but will not now fly until 2013.
The project was saved from cancellation last year by diverting cash from EU agricultural budgets, but now that national governments have to foot most of the bill for its development, there are question marks over its future funding.
GALILEO UNDER CONSTRUCTION
A European Commission and European Space Agency project
30 satellites to be launched in batches by end of 2011-12
Will work alongside US GPS and Russian Glonass systems
Promises real-time positioning down to less than a metre
Guaranteed under all but most extreme circumstances
Suitable for safety-critical roles where lives depend on service
The British government - in line with the official EU position - argues that although the cost of Galileo has grown, its potential commercial benefits have also increased.
One recent study found the benefit to the UK economy of Galileo between 2013 and 2025 is likely to be £14.2bn.
"Sat nav" has certainly become ubiquitous since it was first introduced to the public in the mid 1990s.
The GPS system was originally developed by the US military to target missiles and guide troop movements but now has dozens of commercial applications from helping motorists find their way about to ships' navigation, search and rescue and road pricing.
But why does Europe need its own "sat nav" system when the rest of the world uses GPS or an equivalent Russian or planned Chinese system?
The British government says it is important for Europe to have an "independent" system - to have some measure of control over a technology that now infiltrates every sector of the economy. For example, the time signals delivered by GPS play fundamental roles in electricity distribution, the functioning of the internet and email, and in the security of financial transactions.
Another key difference is that the EU plans for some specialist users to pay for Galileo, whereas GPS is currently free to all who wish to use it. Its advocates also say it will be far more accurate than GPS, which will allow it to underpin a raft of new business opportunities that are currently not possible.
But critics say Galileo is more about the projection of European political power and prestige on the global stage, than any hard commercial benefits.
And although the EU insists Galileo is for civilian use only, opponents suspect a hidden military agenda - that the system could be used to as a guidance system by a future EU army, independent from NATO.
But it is the cost question that is causing the most concern among MPs at Westminster.
The British government has always insisted it will not support Galileo "at any price" - but ministers have been decidedly reluctant to say how much they expect the final bill for UK taxpayers to be.
HAVE YOUR SAY
Last year, transport minister Rosie Winterton told MPs the UK had contributed £96.7m - approximately 17% of the total spent so far - in line with the UK's annual contribution to the EU budget.
Better to invest in space exploration than some of the things this government has piled money into
But, she stressed, that was not necessarily a guide to the amount it might pay towards the project over its entire lifetime, as the UK can withhold funds for specific projects.
Government whip Lord Bassam was even less forthcoming when asked last month in the House of Lords how much Galileo would cost the UK.
"The total estimated costs to 2030 are estimated to be something like £7.8bn. I cannot give a precise figure for the UK contribution, as it is part of a pooled budget," he told peers.
The Commons transport select committee believes the final cost of the Galileo project will be considerably more than that - at least £9.7bn by 2027. If Britain pays 17% of that it will cost UK taxpayers about £86m a year.
But the problem, as with most large-scale, long-term technology projects, is that the final bill is difficult to calculate with absolute certainty.
Leap of faith?
Galileo's supporters argue that such projects always require a leap of faith from the governments involved - who must gamble that the commercial benefits will continue to outweigh the costs, even if those costs spiral far above original estimates. Aerospace giant Airbus faced similar objections in the 1970s, they argue.
Transport Secretary Ruth Kelly came close to acknowledging this last month when she gave evidence to the Commons treasury committee.
"It is absolutely true that the costs have increased," she told MPs.
"However, our estimate of the benefits has also increased and that does not take into account any potential commercial financial opportunities that there will be for the new system."
Galileo, named after the 16/17 century Italian astronomer, has already experienced cost overruns totalling £1.8bn.
But Ms Kelly said Britain had secured an agreement from the European Commission that the project's finances would be scrutinised at key points in its development to discover if costs had ballooned still further.
"Then we would have to reassess the costs and benefits and see what political support we had for a change of policy, and review the case," she told the Transport committee.
So Britain's future involvement will remain under review - but the problem, according to Commons transport committee chairman Gwyneth Dunwoody, is that the European Commission's figures are unreliable and "so muddy it's impossible to see what the costs and benefits would be".
Mrs Dunwoody's committee has branded Galileo "a textbook example of how not to run large-scale infrastructure projects".
It is particularly concerned that the system will be financed from the government's transport budget - money Mrs Dunwoody believes would be better spent on improvements to Britain's transport infrastructure.
"We feel grave reservations about such an enormous sum coming out of transport," says the Labour MP.
"We could clear important transport schemes in the UK with that money - it accounts for two thirds of Crossrail."
The transport committee argues that the Galileo scheme has not been properly managed.
"We thought it essential to have a proper cost benefit analysis," says Mrs Dunwoody.
The satellite could be used for navigation and positioning
"There needs to be made a very good case for this alternative to what there is already available."
The government argues Galileo will be a boost for the UK's satellite industry, one of the country's few high-tech success stories of recent years.
The Department for Transport says that already "UK industry has won contracts valued in excess of 200m euros (£148m) from the European Space Agency."
And UK firms could be in line for an even bigger slice of the commercial action after the government secured an agreement to open up the procurement process to greater competition.
The European Commission estimates that the satellite will, over 20 years, rake in £6.28bn in direct commercial revenue.
In addition, the Commission argues, it will generate £37-44bn of "additional values" - in the form of extra jobs and the increased market share of European businesses making global positioning products, benefiting from the improved technology.
The market it could tap into is predicted to be worth £300bn by 2025.
Benefits to the UK could be further derived if Cardiff is successful in a bid to house the supervisory authority for Galileo.
But will Galileo ultimately be the best use of money from Britain's tightly stretched transport budget? Mrs Dunwoody thinks not.
"In a country that needs very large investment in transport infrastructure, this is nonsense," she tells the BBC News website.
She also questions whether Galileo's supposed technical superiority will be enough to produce commercial success on the scale claimed by the government.
"We just don't think Galileo will work," says Mrs Dunwoody.
"The benefits, it appears to the committee, are far outweighed by any costs."
Here is a selection of your comments on this story.
Galileo will undoubtedly be more accurate than the current GPS system, however for most users the increased accuracy is unimportant. The current system is certainly good enough for road, sea and air transport systems, and when used in triangulation with five or more satellites and surveying is sufficient for construction. AND IT IS FREE! So why would any commercial or private user pay for a service from Galileo?
Steve Georgii, Chertsey
GPS is available to all for free. Why would someone pay for something we can get for nothing? There are doubtless a few marginal cases where it is critical to be able to be accurate to 5 feet instead of ten, but for the vast majority it is irrelevant. This is just another EU boondoggle - which also of course means it will be late, over budget, have massive scope creep, and not be fit for purpose.
Tim Brookshaw, Atlanta, GA, USA
Doesn't make sense to be taking this money from the transport budget - I would suggest CAP reform (and/or UK foreign policy reform) and the freed billions used to invest in research and projects like this one. I do worry that the Americans had there system up in the mid 90s and we are talking about ours not being operational for years (it will be old technology by then.) Also the American GPS systems is as accurate as it needs to be so the benefits of Galileo may be insignificant - will users pay for it when they can have free GPS - I don't think so!
Conor McCartney, Edinburgh
IF it has a military application, then having control of it making us less reliant on the benevolence of a foreign power would have to be a good thing. If on the other hand it is purely civilian, what exactly is it offering that would convince anyone to pay to use it when GPS is free and accurate enough for most of us?! Wouldn't the money be better spent increasing the capacity of our overcrowded railways?
Typical of a pan-European idea like this, the main gainers would be the French with their companies, as it would be biased towards those.
If it does benefit British companies, then that would be great, hopefully the government will then do more to push British interests in Europe!
JohnFromDon, Doncaster, UK
surely the money could be put to better use elsewhere? at the end of the day if you need a remote device to tell you where you are then it is too late.. Please spread this money across local authorities and lower council tax, or at least do something constructive with it!
Craig Rowland, Newport
Scrap the idea, its another mismanaged waste of time. We do not need the prowess that much. We can still accept the contracts to build the satellites but without the need to fund the program.
Why pay for a service like Galileo when GPS is free, GPS version 3 in on the cards and will be as accurate as Galileo and be working on time, if not earlier.
If the public think this is a nice idea then remind them when they have satellite trackers fitted in their cars to charge them for the miles they drive on our roads. Roads that need this money spent directly on them or other UK transport projects not for lining the governments pockets with what they will call a 'green' tax.
Besides we are more closely tied with the US than Europe, you might not like to think so but we are, and will get a raw deal from our EU partners as usual as we put up a large percentage of the funding.
Lets also remember what happens to our large capital projects; mismanaged, always late and over budget. I guess the current budget estimates have missed the VAT out again...
GPS is free...
This sounds like a choice between NATIONAL and PAN-EUROPEAN infrastructure investment. Some will always vote against anything involving cooperation with our European neighbours. I believe that both are necessary but obviously we have limited means. Having lived in France, Belgium and Holland, I can confirm that we have neglected our transport infrastructure. I suspect that opponents of Galileo have other agendas.
Jon Chaplin, Ashford, Kent
The main projected income stream for Galileo is through road charging. This is why road charging WILL happen, regardless of public opinion. The current crop of over-road information boards being erected are already pre-wired with some of the required electronics. Don't think that you have a choice in this - it is pre-determined.
Andrew, Derby, England
Why is it that I keep feeling that EU leaders have a secret agenda? What possible need (other than military) is there for multiple systems of GPS?
It is undoubtedly wise not to leave the US with the monopoly for operating such a service, but as Europe does not need to be ideologically hostile to Russia: why don't we co-operate and work together on developing a common alternative system?
AlexG, Oslo, Norway
There's been talk of a new cold war, perhaps only in passing between governments, but with china being the growing communist giant it is also in the space race... these platforms that china and America have... could these be the platforms for the cold war and if yes... can we defend ourselves from a very futuristic yet somewhat very possible threat coming from the near future?
Steven Davis, Portsmouth, UK/ Gutersloh, Germany
Galileo is a financial disgrace. The Commons transport select committee is spot on with its observations and I believe that the British Government is, as always, being led down the garden path by the French on this one as they are obsessed with Galileo and are now embarrassed by the financial dilemma. We should abandon this monster forthwith as it's another step into a European surveillance society and a fee earner for the EU.
Byron Davies, Cardigan, Wales
Europe and the World needs Galileo. For all those doubters out there, I suggest they have never had to rely on the poor accuracy of the GPS signals we currently receive from the US military satellites. Galileo will have an accuracy 10 times greater. This will revolutionize navigation and commerce. The system will be independent of the Pentagon and the economic benefits worth billions to UK industry. All those doubters out there should burn their British passports and go live in Florida !
Mick Clayton, Madrid, Spain
So...we have to have a system independent of the USA. Like our deterrent missiles, I suppose. Maybe Europe should start up an alternative to Microsoft, in case those revolting colonials decide to switch all our computers off. This is ridiculous.
Has it not occurred to someone for one second, that if there has been an underspend on agricultural subsidies, this should be returned to the taxpayers, instead of spending it on something else?
They're all self-serving and corrupt.
Mac, Fareham, Hants, UK
It really does not matter what you say or think - this will go ahead anyhow. It is part of the great European "vision" that ratchets ever onwards. Please don't think your opinion matters to those concerned with making such decisions.
Robert Layton, Worcester
Given the usefulness of, and dependence on, present GPS it seems daft to be totally reliant on one system with no alternative or backup.
I sometimes wonder why Britain is a member of the European Union. Successive UK governments have done their best to resist every change, development or other opportunity that would allow all of the Member States working together to achieve the economies of scale and independent infrastructure that will enable Europe to compete effectively with the US (and in the future with China and India) on the world economic and geopolitical stage. Or is the real raison d'etre for Britain's "Special Relationship" with the US to prevent us from becoming that competitive. Britain certainly takes policy lines that are in America's interest more often than any other Member State.
Given the ongoing hysterical xenophobia in the US(if you're not with us you're against us), it seems prudent to develop an alternative that isn't dependent on the whim of the US government and military. The fact is, GPS has penetrated almost every area of commerce including aircraft and shipping. Losing the signal would be a crippling economic and military blow, rather than the slight irritant to a few nerds with sat-nav that some of the other commentators appear to believe. Americans aren't idiots.
Adam, Belfast, UK
So nobody will pay for Galileo when they can get GPS for free? The world is full of examples where people will pay for a better service or product, when a free alternative exists. Has nobody seen the success of bottled water over the past 20 years, when a free (but inferior) product is available straight from the tap? Or, to give a transport example, what about the M6 toll road, or Severn bridge?
People will pay for a better service. History and common sense tells us that!
And Galileo will offer a better service. Firstly it too will offer a free service, of higher accuracy than GPS. However, what people will pay for is additional capability: security, reliability and integrity, which will allow users to rely on satellite navigation for business critical functions. At the moment, when GPS goes wrong (as it often does), (a) you usually don't know, and (b) there is nothing you can do about it! Galileo will prevent that, and that is a service worth having if you want to use it for professional applications.
Stuart , Surrey
The current GNSS (Global Navigation Satelite Systems) are NOT sufficient for the vast majority of commercial aviation even with the various augmentation systems currently in operation. There is a complicated issue particularly with calculation of height which will preclude GPS for take-off and landings particularly for low-visibility operations. Whilst a hobbyist might use GPS to navigate his light aircraft, it is not currently (and unlikely to be widescale) licensed by ICAO. It is this exact sector which would be targeted to pay for the Galileo system, but when they already pay for a number of existing systems, are they going to want to cough up again?
Phil Hollingworth, Oxford
American GPS will not be free to use for ever. When the American military, who own it, see a convenient way to rake in the millions projected for Galileo, then it will surely cease to be free. I suggest it might be better not to wait for that to happen.
The costs of Galileo will be tiny compared to the costs of an effective ABM system to guard European countries. Within twenty years or less the world will be divided between those inside and those outside such systems. The response to Galileo shows that Britain will be the end up as the furthest outpost of the American system.
I believe that the vast majority of respondents have completely missed the point of Galileo. 8 years ago as one of his last acts as President Bill Clinton turned off 'selective availability' - a deliberate degrading of the civilian GPS signal and overnight positioning accuracy went from 100m to 10m. GPS is primarily a military system and the US will, and can, turn it off when ever it wants. They can even turn it off on a regional basis and have tested just that around Northern Scotland causing havoc with the offshore Oil industry several years ago.
Why else have the Chinese and Russians developed their own GNSS systems? It's about independence and EU security, you Brits might like being American poodles but the rest of the EU would like some future proofing of our military and civilian 'critical' systems. Freedom has a price!
james k, london
GPS is fine and I speak as a maritime professional who uses GPS daily. If you want better accuracy DGPS Differential GPS) is available which allows "civilians" to have accuracy measured in centimetres. USA will not turn it off as their own infrastructure that is reliant on it will crash. This is a EU vanity project which if it comes to fruition will try and recoup its cost from its users who paid for it in the first place through taxation.
Sean O'Toole, Chandlers Ford
This is one important step for Europe to becoming completely independent and self sufficient. We need to stop looking up to the US. Europe has always been on top with the exception of the cold war era. The EU will bring us back up.
Vic, Stockholm, Sweden
The British government should decide whether they want the UK to be American or European and act accordingly because in a few decades time it won't be possible to be both. At least as Europeans you will still be entitled to be British.
John Hoare, Kildare, Ireland
The cost is equivalent to building just under 3 miles of roads per year (at current price of £30m per mile) which is pretty cheap for the potential technology gains which could be obtained.
Chris Johnston, Glasgow
I would suggest to all those that see fit to whine that they don't really understand what the actual benefits are, or could be. And that they are leaving their comments based on an article that focuses on cost and little else. Please at least scroll up where you can click on a Q&A link, so you can make an informed decision before dismissing out of hand.
james allen, london, uk