According to Branson, who is linking up with the firm behind SpaceShipOne which in June became the first private manned craft into space, up to 3,000 astronauts could fly into space over a five-year period.

If his prediction comes true, it will break the monopoly of state-funded space travel and open up outer space to those with the wherewithal to pay for it.

The concept of space tourism took shape in 2001 when US multi-millionaire Dennis Tito paid 20 million dollars, or 1,800 dollars per minute, to make his dream come true by stepping on to the International Space Station from a Soyuz spacecraft.

Marketing firm Yankelovich has determined that 55 million people would be willing to go on a two-week space cruise aboard a space shuttle. It would cost one billion dollars to refurbish the shuttle fleet, but Yankelovich estimated that NASA could make 30 billion a year from space tourism.

Several companies have already gone into business to bring "democracy" to outer space.

Space Adventures has high hopes of offering commercial trips into space for a mere 98,000 dollars, while Space Island is more ambitious, hoping to build its own space station and a shuttle fleet to serve it by 2007, and Bigelow Aerospace is thinking of building a hotel on the Moon for 100 top-paying customers and a staff of 50.

But the idea remains in its infancy as no-one has yet been able to collect the 10 million dollars on offer for the so-called "the X Prize" to reward the first privately-funded team to safely launch and land a manned vehicle into space with three adults on board twice in two weeks.

The X Prize, primarily financed by private companies in Saint Louis, Missouri, is based on the proposition that space travel should be open to all and that commercial forces, not governments, are best suited to make it happen.

US aviation pioneer Burt Rutan, who designed and built SpaceShipOne, looks to be closest to claiming the prize, ahead of 26 other competing teams, his craft having shot into the history books in June when it became the first non-government manned spaceship to travel beyond the 100-kilometre (62-mile) boundary of space and back again with Mike Melvill, a 62-year-old South African-born pilot, at the controls.

But in August, there was disappointment for Phillip Storm and Eric Meier, presidents of Space Transport Corp, when their craft, Rubicon 1 with three test dummies aboard, blew up shortly after lift-off over the US Pacific coast.

The other teams in contention are from Argentina, Canada, Great Britain, Israel, Romania, Russia and the United States. A Canadian competitor is next up, with plans to launch a ship into space on October 2.

The private California-based firm, TransOrbital, which claimed it was the only private company to be allowed by US authorities to operate commercial flights to the Moon with its Trailblazer satellite, staged a test in 2002 when it launched a dummy craft into the Earth's orbit from a Russian rocket.

But the first commercial Moon mission, paid for by corprate sponsorships and advertising and originally scheduled for 2001, was delayed.

Yet there has been strong support for the notion of commercial space travel from someone who knows what the business is all about -- Buzz Aldrin, the second man to walk on the Moon.

He told US Congress: "Privatization will make it possible for your average citizen to travel into space. Space tourism is a big market that, once it takes off, will grow astronomically. And when that happens it will reduce the cost tremendously."

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