Post by kieransan on Jun 5, 2013 6:57:12 GMT
Life on the International Space Station is luxurious. Its living accommodation is spacious, with two bathrooms, two toilets and a gym. There's also Wi-Fi, DVDs, musical instruments, even fresh fruit on a good day. Some occupants even have enough leisure time to film themselves performing David Bowie tunes.
The first US space station was rather more basic. Forty years ago this month, Skylab took off aboard a Saturn V rocket from the Kennedy Space Centre in Florida. It was a bridging mission by NASA, intended to fill the gap between the Apollo moon landings and the Space Shuttle yet to come. With only one window, drinking water that made the astronauts fart, bland food, and an on-board excrement store (for scientific purposes), it was like a garden shed to the ISS's Taj Mahal. But, garden shed or not, Skylab was home to nine astronauts in 1973 and 1974.
Back in 1973, nobody was even sure that humans could live and work in space for an extended period. By the end of that year, the station crews had racked up more hours in space than all the world's previous missions put together, and NASA had learned a lot about how weightlessness affected human physiology.
Being in orbit, Skylab was constantly in free fall around Earth, circling at more than 25,000 kilometres an hour. The astronauts found they soon got used to the feeling, though, reporting that, bar the initial motion sickness, life was pretty normal. It was harder to adjust when coming back to terra firma. After months in space, the body's muscles waste and so the astronauts had difficulty walking.
Bad habits
The most frequent problem for returning astronauts was that they had picked up bad habits. In zero gravity there was no problem if they just let go of an object – it would float off. When they returned to Earth, such an attitude resulted in a few breakages.
Skylab's crews collected their own excretions for good reason: they brought them back to Earth so doctors could study how bodily processes change in space. Among other things, they found that peristalsis – the movement of food through the digestive tract – slowed, although not to a degree hazardous to health.
Perhaps the quirkiest thing we learned is that under weightless conditions, astronauts don't get dizzy when spun around. A seat, looking much like a dentist's chair, on board Skylab was used to spin astronauts at speed while their reactions were monitored, leading to the discovery that the inner ear needs gravity to register dizziness.
Skylab also served as the greatest solar observatory of its time, a microgravity lab, and an Earth and environment-observing facility. Yet despite all the sophistication of the labs, some of the more childish experiments proved to be the most repeated. Letting a blob of water float around the station until it struck another astronaut in the face proved to be inordinately popular. But such lessons guided future space station design, including both the Russian Mir station and the ISS. Skylab revealed the most useful places to put footholds and handles, the benefits of using Velcro in space, and the need for padded areas to avoid harm from astronauts or their instruments banging into surfaces. It also pioneered the use of zero-gravity showers, vital when you are cooped up with other humans.
Accident-prone
These insights were hard won. The mission was fraught with trouble from the start, when Skylab's meteoroid shield was accidentally deployed just after launch. It ripped away, damaging the onboard workshop's solar array. Solutions had to be found before astronauts could visit the station and, once aboard, the first crew spent much of the time on DIY fixes, including deploying a makeshift parasol to reduce solar heating. A leak in one of the engines even had the second crew on the verge of an emergency rescue until they thought up another ad hoc fix at the eleventh hour.
NASA had intended crews to continue to use Skylab after the launch of the shuttle programme, after which it was to be boosted into a higher orbit. This never came to pass, in part because intense solar activity made the atmosphere more dense where Skylab was in orbit, causing the orbit to degrade. Skylab eventually met an undignified end, burning up over the Indian Ocean and Australia in July 1979. But the trail the world's first space station blazed is what made the ISS possible today.