Physicist Stephen Hawking in Zero Gravity Stephen Hawking (center) enjoys zero gravity during a flight aboard a modified Boeing 727 aircraft owned by Zero Gravity Corp. (Zero G). Hawking, who suffers from amyotrophic lateral sclerosis (also known as Lou Gehrig's disease) is being rotated in air by (right) Peter Diamandis, founder of the Zero G Corp., and (left) Byron Lichtenberg, former shuttle payload specialist and now president of Zero G. Kneeling below Hawking is Nicola O'Brien, a nurse practitioner who is Hawking's aide. At the celebration of his 65th birthday on January 8, 2007, Hawking announced his plans for a zero-gravity flight to prepare for a sub-orbital space flight in 2009 on Virgin Galactic's space service. #NASA #science