Hawking spreads his wings

After nearly 40 years confined in a wheelchair, Stephen Hawking finally broke free from terra firma on Thursday night for a few moments of freedom in zero gravity.

It was a brief history of weightlessness for the theoretical physicist as a specially modified jet simulated the experience of space travel during 25-second plunge over the Atlantic.

The parabolic flights, similar to those used to train astronauts, are commonly referred to as "vomit comets".

Two doctors and three nurses accompanied Professor Hawking, 65, taking him out of his wheelchair and placing him gently on the floor of the jet's padded interior as the Boeing 727 climbed steeply to 34,000ft before plunging to 24,000ft.

The plane had been kitted out with medical equipment sufficient for a mini-intensive care unit. He was attached to monitors measuring his blood pressure, heart rate and oxygen levels, while his head was cushioned with a custom-made restraint.

Prof Hawking, the first disabled person to experience weightlessness, planned to communicate with his aides through nods and smiles.

Prof Hawking admitted that he was more worried by the discomfort from the periods of increased gravity as the plane climbed. A nurse lifted his paralysed arm to wave before he boarded the jet.

A lift carried his wheelchair aboard, and then the wheelchair was returned to the ground. "As you can imagine I'm very excited," he said. "I have been wheelchair-bound for almost four decades. The chance to float free in zero-g will be wonderful."

Motor neurone disease

The Cambridge University scientist was diagnosed with motor neurone disease when he was 22. He is unable to talk or move his limbs, relying on a computer to provide a synthesised voice. US company Zero Gravity usually charges £1,915 (Dh14,062) for such trips, which take off and land from the space shuttle runway at Nasa's Kennedy Space Centre in Florida.

Prof Hawking, whose best-selling book, A Brief History of Time, popularised the theories of quantum gravity, has always wanted to journey into space. Until Thursday, the closest he had come was a guest appearance in Star Trek. "I have wanted to fly in space all my life. For someone like me, whose muscles don't work very well, it will be bliss to be weightless," he said.

Prof Hawking is keen to popularise public space travel because he believes that life on Earth may eventually be wiped out.

"I think the human race doesn't have a future if it doesn't go into space," he said. "I therefore want to encourage public interest in space. A zero gravity flight is the first step towards space travel."

Prof Hawking has reserved a place for a sub-orbital flight with Sir Richard Branson's Virgin Galactic venture, which aims to begin taking people into space in 2009. "He's very game for it and was grinning from ear to ear when I explained how it would feel," said Peter Diamandis, the founder of Zero-G.