It’s time to abandon Earth, the world’s most famous theoretical physicist Stephen Hawking has warned.

“I believe that the long-term future of the human race must be in space,” Hawking told Web site Big Think during a global forum.

“It will be difficult enough to avoid disaster on planet Earth in the next hundred years, let alone the next thousand, or million. The human race shouldn’t have all its eggs in one basket, or on one planet,” he said.

Hawking also suggested that if man can avoid disaster for the next two centuries, the earth should be safe as the human race spread into space.

However traveling to another planet will prove a challenge. University of Michigan astrophysicist Katherine Freese said “the nearest star to Earth is Proxima Centauri, which is 4.2 light years away. That means, if you were traveling at the speed of light the whole time, it would take 4.2 years to get there” — or about 50,000 years using current rocket science.

This is not the first time Hawking has warned of impending planetary doom. In 2006, the physicist warned that Earth was at an ever increasing risk of being wiped out.

In April, he warned of the dangers of communicating with aliens from outer space. And in May, Hawking said he believed humans could travel millions of years into the future and repopulate their devastated planet if spaceships are built that can fly faster than the speed of light.