Anyone watching Channel 4's Space Cadets "reality show" may be fooled into believing that training for a space mission is effortless. But aspiring astronauts should beware. The actual programme is daunting - a physical and mental challenge to deter all but the toughest aspirants.
The first obstacle is the candidate selection process. Unless you happen to be a multi-millionaire tourist, there is likely to be competition from hundreds of others eager to experience the final frontier. Since the commander of the spacecraft is invariably a military pilot who has flown thousands of hours, most would-be astronauts have to settle for a window with a view. Everyone who wants to join the ranks of Nasa's finest must have an advanced degree in engineering, science or mathematics, along with considerable experience in a space-related occupation.
Another basic requirement is physical and psychological fitness. Although today's astronauts no longer have to be super-fit pilots, no one can experience the weightlessness of space without a rigorous medical. For those that pass, age is not a barrier. Many astronauts who have passed their 50th birthday have now flown in space, including the 77-year-old John Glenn, who spent nine days orbiting the Earth.
Defeating the hordes of other applicants in the competition is only the first step along a rocky, sometimes tedious, road. Basic training lasts for at least a year. Anyone averse to lectures should avoid applying, since new recruits typically have to study about 230 subjects and survive some 1,600 hours of tuition.
Each of the partners in the International Space Station programme follows similar guidelines when training its astronauts. But where American trainees enjoy the comfortable, air-conditioned facilities of humid Houston, their Russian counterparts have to endure Star City near Moscow, a crumbling military legacy of the former Soviet Union.
At Star City, little has changed in 40 years. Physical training plays a much bigger role, including tests that are no longer required for US astronauts. Among the most dreaded are sessions in the centrifuge or "spinning chair", which subjects occupants to a chest-crushing eight times normal gravity. The force pulls blood from the head and can lead to black-outs. Even millionaire tourists cannot escape this torture. Russian doctors insist that the machines are good predictors of those who will be vulnerable to space sickness (something that their US counterparts deny).
In this era of multinational crews, language skills (particularly in Russian and English) take on a much greater significance. Indeed, some outsiders training at Star City describe their language lessons, one-to-one lectures and oral exams as a more tortuous than any centrifuge session. "Four hours of Russian a day used to feel like brain surgery without anaesthetic," the South African businessman and space tourist Mark Shuttleworth commented.
Familiarity with weightlessness is essential for anyone preparing to go into space. By taking a rollercoaster ride on a large, specially adapted aircraft - nicknamed the "vomit comet" by trainees - astronauts can experience 30-40 seconds of microgravity as the plane goes "over the top" on its sine-wave flight path. Over several hours, the crew "enjoys" 30 of these brief, stomach-churning episodes.
More advanced training includes lengthy sessions in a huge water tank, where astronauts encased in bulky pressure suits float around a spacecraft mock-up as they rehearse complex extravehicular activities. Each six-hour spacewalk will typically be rehearsed 10 times in the tank. Although no shuttle has ever missed the runway during its return to Earth, astronauts still have to practise an emergency evacuation from an orbiter that has ditched in the ocean. Such techniques are even more imperative for ballistic capsules like those still used on Russian missions today.
Since a malfunctioning Soyuz spacecraft may land in a frozen forest or splash down in a remote lake, all cosmonauts have to undergo survival training. The exercise in a wintry woodland would appeal to any outdoor adventurer - gathering firewood, making a shelter from a parachute, fending off wolves with a gun and firing flares to attract rescuers.
Learning to survive a Soyuz splashdown could be even worse in the heat of high summer. British cosmonaut Helen Sharman explains: "It took us almost three hours to get out - there was a strong smell of vomit by the time we'd finished. Your relationship with the other people in the crew is tested to the limit."
Each crew member - even a paying visitor - must be able to carry out routine tasks, such as changing the canisters that remove carbon dioxide from the air. Much of the systems training takes place in simulators, where controllers throw any unexpected situation at the crew, including a full-blown emergency. As the launch approaches, crews travel the world, familiarising themselves with the hardware of each space station partner.
Is there any way to avoid the years of toil and sweat? If you really want to be a space cadet, for $200,000 (£130,000), Richard Branson's Virgin Galactic is offering a one-hour suborbital flight which will include 20 minutes in space and five minutes of weightlessness. The first-class space tourist will simply have to undergo six days of medical preparation, some gravity-tolerance training, sessions on the simulator and chats with experts about how to get the most from the experience. In a few years, thousands of people may be able to afford an experience that is out of this world.
Peter Bond is the communications office of the Royal Astronomical Society. His new book, Distant Worlds, will be published by Copernicus next springReuse content