BEIJING, March 2 (Xinhuanet) -- British cosmologist Stephen Hawking, known for his best-selling book "A Brief History of Time" and the fact he is confined to a wheelchair because of Lou Gehrig's disease, will take the first step to fulfill his dream to journey into space when he takes a zero-gravity ride on a plane next month.

World renowned British scientist Stephen Hawking of Cambridge University speaks to students at the Bloomfield Museum of Science in Jerusalem, Dec. 10, 2006. (Xinhua/AFP Photo) Photo Gallery >>>

    On April 26, Hawking will be wheeled aboard a special Zero Gravity Corporation Boeing 727-200 and experience a roller-coaster ride at 30,000 feet that produces periods of weightlessness - a unique sensation for a scientist who has devoted his life to the study of gravity.

    The flight usually costs 3,500 U.S. dollars, but is free to Hawking. Peter H. Diamandis, chief executive of Zero G, which has been offering the rides since 2004, said "the idea of giving the world's expert on gravity the opportunity to experience zero gravity" was irresistible.

    Hawking announced on his 65th birthday, in January, he hoped to take a longer, higher flight in 2009 on a space plane being developed by Richard Branson's company Virgin Galactic, which seeks to take six passengers to an altitude of 70 miles.

    Diamandis, a space entrepreneur who is a founder of the 10 million dollar Ansari X Prize, awarded in 2004 for the world's first private spacecraft, on which the Branson craft is based, said he had offered Hawking a ride after hearing him express enthusiasm for spaceflight.

    Branson has decided he will personally finance Hawking's ticket into space -- a flight that would normally cost 200,000 dollars.

    "He's one of the greatest physicists of all time," Virgin Galactic president Will Whitehorn told The Associated Press earlier this year.

    Hawking says he wants to encourage public interest in spaceflight, which he believes is critical to the future of humanity.

    "I also want to show," he said in an e-mail interview, "that people need not be limited by physical handicaps as long as they are not disabled in spirit."

    Last summer, at a news conference in Hong Kong, Hawking said humanity's ultimate survival depended on colonizing the solar system and beyond.

    "Life on Earth," he said, "is at the ever-increasing risk of being wiped out by a disaster, such as sudden global nuclear war, a genetically engineered virus or other dangers we have not yet thought of."

    At an age when many of his contemporaries are thinking about retirement, Hawking seems determined to add yet another chapter to a tale of already legendary adventurousness and determination, not to mention scientific achievement.

    He was a graduate student at Cambridge University in the 1960s when he was found to have amyotrophic lateral sclerosis, or Lou Gehrig's disease, which usually kills its victims in two to five years. He persevered to get his degree and become the world's reigning expert on black holes, the bottomless pits in which gravity has crushed dead stars, space and time out of existence.

    Along the way he has married twice, fathered three children (he is now a grandfather), written the best-selling "A Brief History of Time" among other books, traveled the world and appeared as a guest on "Star Trek: The Next Generation" and "The Simpsons."

    Hawking has been to the White House, the Great Wall of China and Antarctica, met the Dallas Cowboys Cheerleaders and been lowered into the pit of an underground particle accelerator.

    Lawrence M. Krauss, a cosmologist from Case Western Reserve University, who once took him down in a submarine, said, "Stephen is a dreamer and an adventurer who enjoys the opportunities his celebrity brings in a way that happily perhaps compensates, although only minusculely, for his physical affliction."

    The image of Hawking journeying to the stars in his wheelchair has become a symbol of humanity's restless curiosity and wonder.

    (Agencies)