Gravity expert Professor Stephen Hawking said "Space, here I come" after he experienced weightlessness aboard a specially-modified aircraft.
The renowned theoretical physicist, who is almost totally paralysed by motor neurone disease, left his wheelchair behind during the two-hour jet flight that gives passengers 25-second bursts of weightlessness by making parabolic plunges.
The jet - a modified Boeing 727 - made eight dives for Prof Hawking, his physicians and nurses and two dozen other passengers.
Prof Hawking, who is already making plans to go into space, said: "It was amazing. I could have gone on and on."
Peter Diamandis, chairman of Zero Gravity Corp, the company that owns the jet, said during two of the plunges Prof Hawking made two flips like "a gold-medal gymnast".
Mr Diamandis, who accompanied Prof Hawking on the flight, added: "We had a wonderful time. It was incredible, far beyond our expectations."
Prof Hawking who took a motion sickness pill prior to the flight as a precaution, spoke last year of his desire to go into space.
He appealed to Virgin boss Sir Richard Branson, who plans to provide sub-orbital rides to paying passengers as early as 2009.
Sir Richard has agreed to "fix it" for the professor and to arrange a Virgin Galactic flight for him.
Sam Blackburn, Prof Hawking's assistant, said the flight was "a test to see how well he can handle the g-forces that would be necessary in order to leave the atmosphere".
