Photos: Stephen Hawking's zero-gravity flight

For a short while on Thursday, physicist and author Stephen Hawking was up and out of his wheelchair-- and out of the grip of gravity. The weightless experience aboard an airplane in Earth's atmosphere underscored a point Hawking has been making in recent months: that the future of the human race is in outer space. Hawking called the experience "amazing," saying in a statement "I could have gone on and on--space here I come."

The flight took off from the space shuttle landing facility at NASA's Kennedy Space Center in Florida, under the auspices of a company called Zero Gravity. Zero-G's founder and CEO, Peter Diamandis (at right), is a prominent backer of commercial space travel and helps run the X Prize Foundation, which has broadened its scope beyond space ventures to other fields of science, from genomics to energy efficiency for cars. At left is astronaut Byron Lichtenberg.

Photo by Zero Gravity