Sir Richard Branson has kick-started a new space race, with plans to begin tourist trips to the edge of the atmosphere. But are we ready for holidays at the final frontier?
Cambodia now passť, Antarctica so last year and white-water rafting down the Zambezi far too tame these days? Relax. Space tourism may be about to provide a fresh, final-frontier tourist high.
Sir Richard Branson has just announced a £14m agreement with a US company, Mojave Aerospace Ventures, which promises to make astronauts of us all - or at least those who can afford a £100,000 seat in his spaceship. No doubt Virgin Galactic, as Sir Richard has christened his future service, will market that as a bargain £10,000 return fare with £90,000 in airport taxes.
Travel in space may sound like some sad Trekkie fantasy. But reputable figures are arguing that the entry of the private sector into what has previously been a government domain really does put space travel within the reach of ordinary people.
The technology is certainly there. In June, Mojave Aerospace Ventures, whose key figures include Burt Rutan, an eccentric aerospace engineer with a penchant for wearing knee-high socks over golfing trousers, and billionaire co-founder of Microsoft, Paul Allen, used that technology to send the first private vehicle into space. SpaceShipOne, piloted but passengerless, shot into the skies over the Mojave Desert and spent three minutes in suborbital space - 62.5 miles from Earth - before returning to Earth.
So what is on offer to tourists should the commercial space dream actually achieve lift-off? Well, there's that unique sensation of weightlessness, an out-of-this-world view of the Earth's blue-black curvature and - most important - the chance to drop the killer line "when I was in space" at parties. Beat that you Victoria Falls bungee jumpers.
But space also harbours unique health risks. While mundane holiday health concerns, such as sunburn and midge bites, would be left behind on dull old Earth, spacey free-floating could give a whole new meaning to travel sickness.
The aptly named Vomit Comet, a specially customised plane that allows passengers to float freely for about 30 seconds at the top of a rapidly-reached, Earth-bound trajectory, is proof of that. Typically one third of the VC's passengers throw up at the climax of their trip. Just one passenger needs to vomit to set off a chain reaction. Nice.
Space writer Sean Blair, who has had the zero-gravity experience on a customised European Space Agency craft, says a cocktail of travel sickness pills and amphetamine can stave off space sickness. And then it really is fun.
"First you are pushed back as if you were on a fairground ride and then suddenly, as if a switch had been flicked, you are weightless and floating," he says. "I found it quite pleasant. When free-floating, the slightest movement produces big effects. The plane is padded inside so you don't hurt yourself." Nod forward and you can find yourself on the ceiling. Nod again and you make like a spin dryer.
Continental breakfast included?
The short, free-floating forays into sub-orbital space being promised by Virgin Galactic probably harbour no other health threats bar puking. However, if this first small step for commercial space travel opens up the entire Solar System, complete with four-billion-star hotels (that's the view from the window), self-catering in orbiting space stations, roving-galaxy gap years, and the 1,000-mile-high club, then space tourism could make you sick.
Too much space does horrible things to you. It causes a special form of osteoporosis and its higher radiation levels increase cancer risks. In space, heart muscle also shrivels. Earthly Delhi Belly does begin to look a bit of a picnic.
But there's more. If you think jet lag is bad, you haven't tried space lag. Professor Russell Foster, of Imperial College, London, is working for the US National Space Biomedical Research Institute investigating the effects of space on the human body. He thinks the inability of our internal clocks to adapt to new patterns of night and day may hamper space exploration.
As a result, Mr Foster warns, space tourists, like astronauts, could face the kind of dire health problems suffered on Earth by shift workers. "Shift workers are 40% more likely to have heart attacks," says Professor Foster, before pulling ulcers, chronic insomnia and poor concentration from a terrifyingly long list of space maladies. One solution would be spacecraft without windows, with internal light manipulated to mimic Earth's day and night. "Spacecraft without windows would be a bit of a disaster for space tourism," concedes Professor Foster.
A chance to avoid the crowds at least
Space can do strange things to the mind as well as the body. Russian psychologists report that extended stays in space cause hypersensitivity, nervousness and irritability. It might be the confined space or perhaps the realisation, from a lofty new perspective, that you, and the Earth, really are just fleas on the back of the Universe.
Buzz Aldrin, the second man on the Moon, had a nervous breakdown when he returned to Earth. He had a warning for thrill seekers. "When you have been to the Moon, what's left?" he asked. Neil Armstrong fell to Earth and gained a reputation as a recluse. The eighth man on the Moon, the late James Irwin, looked into space and "felt the power of God as I have never felt it before". When he returned to home, Irwin quit the astronaut scene and founded an evangelical church.
Space missions gave way to earthly ones. Irwin travelled to Turkey twice in search of Noah's Ark. Compared with space travel, you might think that a trip to Turkey was a whole lot better for his health.