Stephen Hawking is back on solid ground after completing eight "zero gravity" plunges aboard the vomit comet.

In total, the professor spent around four minutes weightless. On his return, he described the experience as "amazing", proving that even a genius can have his vocabulary humbled by free-fall. "The zero-G part was wonderful and the higher-G part was no problem. I could have gone on and on," he told the BBC.

"Space here I come," he added, referring to his plans to fly aboard one of Richard Branson's first Virgin Galactic sub-orbital flights, which are slated to start in 2009.

Peter Diamandis, chairman and CEO of Zero Gravity Corporation, the firm that took Hawking up on the specially modified Boeing 727, said that the flight had been beyond all their expectations.

"The doctors felt he was in tremendous condition. His heart rate, blood pressure, oxygen levels were all normal and perfect," he said.

You can have a look at the good professor spinning like a turbine here on YouTube. ®

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