Stephen Hawking: Colonize other worlds

CAMBRIDGE, England -- Stephen Hawking was too ill to attend a conference in honor of his 70th birthday yesterday, but in a recorded message played to attendees he repeated his call for humans to colonize other worlds.

Cambridge University Vice Chancellor Leszek Borysiewicz told the conference that the renowned physicist, who is almost completely paralyzed because of Lou Gehrig's disease, had only recently been discharged from the hospital for an unspecified ailment.

In his message, Hawking pleaded for interplanetary travel, arguing that humans faced a grim future unless they spread out from their terrestrial home. "I don't think we will survive another thousand years without escaping beyond our fragile planet," he said.

Hawking's speech -- delivered in his distinctive, robotic monotone -- charmed the audience of scientists, students and journalists gathered at Cambridge's Lady Mitchell Hall.

Borysiewicz said Hawking had "transformed our understanding of space and time, black holes, and the origins of the universe," adding that he hoped that the scientist was watching the proceedings online. "If you're listening Stephen, happy birthday from all of us here today," he said to a round of applause.

A black hole expert, Hawking is one of the leading lights in theoretical astrophysics. His achievements are all the more remarkable because of his Lou Gehrig's disease, an incurable degenerative disorder with which he was diagnosed as a 21-year-old.

Most people die within a few years of the diagnosis, but Hawking has defied the odds and spent half a century carrying out pioneering research.

His series of works popularizing the latest developments in theoretical astrophysics have been best sellers. "A Brief History of Time," published in 1988, alone has sold millions of copies. A host of other books, including "A Briefer History of Time," have followed.

Nevertheless the condition, known as motor neuron disease in the U.K., has made life difficult. Since catching pneumonia in 1985, he has needed round-the-clock care.

Hawking relies on a computerized wheelchair and a voice synthesizer to speak.

Borysiewicz didn't say when Hawking was hospitalized or specify the nature of his condition, but he did say that Hawking would be well enough to meet some of the attendees over the next week.