A British company is offering seats to adventurers willing to go the extra mile on a historic journey to the moon.

The first 500,000-mile round trip in a converted Soviet-era space station could take place as early as 2015.

Art Dula, founder and chief executive of Isle of Man-based Excalibur Almaz, told a space tourism meeting in London: "We're ready to sell the tickets."

Only those with the "right stuff" should apply: besides the necessary level of physical and mental fitness, that includes a likely fare of around £100 million per person.

US space entrepreneur Mr Dula has acquired two Soviet "Almaz" space stations, designed for orbital spying operations.

Thrusters attached to the stations will convert them to long-distance spaceships.

Four re-entry capsules, or re-usable return vehicles (RRVs), will ferry three people at a time to the orbiting space station and return them to earth.

All the space vehicles - the cost of which is confidential - are housed in hangers on the Isle of Man. One of the RRVs is currently being exhibited outside the Queen Elizabeth II conference centre in Westminster, London.

If the bold plan succeeds, a private British space company will carry out the first manned moon mission since Apollo 17 in 1972.

The aim is for three people to fly to the moon, orbit the lunar surface and return safely to earth, parachuting to the ground in an RRV. Much of the actual flying will be computer-controlled and all necessary training, including the human skills needed to pilot the spacecraft, is provided in the package.

Speaking at the Royal Aeronautical Society in London, Mr Dula outlined his company's ambitious plan.

Marketing studies suggested, at a "conservative estimate", that around 30 moon-mission seats could be taken up between 2015 and 2025: enough for one mission a year.

The RRVs can be used 15 times and each space station has a service life of 15 years.

Mr Dula stressed that the moon mission goes far beyond "space tourism" of the kind offered by Sir Richard Branson's Virgin Galactic. The trip would be a "private expedition" rather than a sightseeing tour.

"Excalibur Almaz is willing and able to send crewed missions deeper into space than would be possible aboard any other spacecraft in existence today," said Mr Dula.

"Our fleet of space stations and re-entry capsules enables us to safely fly members of the public to moon orbit as early as 2015.

"There is not a single other vessel, owned by a government or the private sector, that is suitable for a manned flight to lunar orbit, utilising proven technologies.

"The EA fleet has previously flown to space several times and will undertake many more missions. It contains vessels of a design that has spent thousands of hours in space successfully. This is scientific fact, not fiction."

A giant Russian Proton rocket, launched from the Baikonur Cosmodrome in Kazakhstan, will put the 30-tonne space station into orbit. One of the two Salyut-class space stations will be kept in reserve on the ground.

Smaller Soyuz FG launch vehicles will lift the shuttle capsules.

The station has 90 cubic metres of living space and provides a protected "refuge" where crew members can shelter in the event of a solar radiation storm.

Although the programme involves US personnel and Soviet technology, Mr Dula sees it very much as a British enterprise.

He says he chose the Isle of Man not only to take advantage of its tax benefits but because it is a hub of space industry. Of the 54 international space satellite companies, 30 are based on the island.

"Let's talk about being a space-faring society like we were a sea-faring society. It's exactly in the same vein as the historic exploration that was done by Europe and the British Isles over the last several centuries that resulted in so much growth," Mr Dula told the meeting.

He has even more far-reaching plans to develop an entire private space programme serving governments, companies and members of the public.

As well as expeditions to the moon, he envisages unmanned research missions, transportation of people and cargo, and chartered space exploration flights.

"We've already had billionaires who have said they will mine the asteroids," he said. "This is a paradigm shift ... whether we do it or somebody else does it, it's never going to go back to being national space programmes."