美宇航局高薪聘長期臥床志愿者

查看原文

Are you someone who will happily spend days sprawled on your sofa watching TV?

Or could you sit in the same spot for hours with only a computer game for company?

If you answered yes to any of the above questions, then the future of human space travel could rest with you.

Nasa is recruiting volunteers to lie a bed for 70 days to research the effects of microgravity on the human body.

And the study, which is on-going, will give you around ￡3,137 ($5,000) a month for the pleasure.

The study takes place at the Johnson Space Centre in Houston where you stay for two weeks, doing every day activities, so that scientists can monitor your body in normal conditions.

You then spend 70 days in a tilted bed where you will have light for 16 hours per day and darkness for eight hours per day.

Access to computer games, TV, books, the internet and visitors is permitted, and all food is provided to keep you at a constant weight.

You can even get a shower while you’re in bed.

The only time you can move is when scientists carry out tests to find out any changes in bone, muscle, circulation, nutrition and the immune system.

Or as part of the newly-introduced exercise called the ‘countermeasure and function testing’ study, that will monitor how different movements can effect muscle size and strength, bone health, and cardiovascular function.

Even then you will be lying in bed and will exercise on specially-designed equipment.

Following 70 days, there is a 14-day rehabilitation period to get your body back into shape.

If all this sounds like your dream come true, applications can be made here.

Self-described ‘pillownaut’ Heather Archuletta has taken part in the study three times.

‘I'm a very active person, so it's difficult to be restricted to bed sometimes, but many of us are willing to do it for the sake of future space exploration,’ she wrote on her blog.

‘The... money... is... pretty freaking awesome, however. About $5,000 per month, which is great if you've just graduated, can't find a job, are between jobs, or just plain love space exploration,’ added Ms Archuletta.

A similar study is being undertaken by the European's Space Agency's (ESA) Programme for Life and Physical Sciences at the Medes Institute in Toulouse, France.

But while it may sound like easy money, it isn’t the walk in the park that it might first seem.

During extended periods, microgravity takes a serious toll on the human body.

Without the pulls of normal gravity, blood doesn't flow downhill, but pools in the extremities including the face, hands and feet, causing a puffy appearance.

And without that downward pressure, height increases.

Body mass often decreases with a loss of muscular tissue from nitrogen depletion; the veins and arteries of the legs become weaker, anaemia occurs, accompanied by a reduction in blood count.

The most serious concern is the loss of bone calcium that increases with the length of a mission.

The calcium loss from bones subjected to extended microgravity takes place at 10 times the rate of an elderly person suffering from osteoporosis.

Astronauts report an overall feeling of weakness and loss of balance upon return to Earth, though recovery is nearly complete after a week.

Researching the effects of microgravity has been an on-going programme at Nasa for the past 25 years.

There are a number of other ways to create low-gravity environments on Earth for research, but these last for short periods of time.

For instance releasing experiment samples from tall drop towers provides about four seconds of microgravity.

Research aircraft can expose experiments to about 30 seconds of low-gravity while the aircraft approaches the top of a steep climb and begins a sharp descent.