英国著名物理学家史蒂芬·霍金日前在接受美国著名网站BigThink访谈时，再曝惊人言论，称地球将在200年内毁灭，而人类只有移民外星球才能继续存活。

Humans: It’s time to abandon Earth or face extinction¹.

It could be the plot（情节，阴谋） of a summer blockbuster（轰动，巨型炸弹） , but this prediction isn’t science fiction（科幻小说） . It’s a glimpse of the future, according to famed British scientist Stephen Hawking².

"I see great dangers for the human race," he said in an interview with global forum³ Big Think. "There have been a number of times in the past when its survival has been a question of touch and go（快速的行动） ."

Hawking, an award-winning physicist⁴, says humans must evacuate⁵ our home planet within the next two centuries and expand into space to survive.

"I believe that the long-term future of the human race must be in space," he said. "It will be difficult enough to avoid disaster on planet Earth in the next hundred years, let alone the next thousand, or million."

Hawking, who was awarded the Presidential Medal of Freedom last year, has recently voiced many concerns about the future of life on Earth.

In April, he spoke⁶ pragmatically（讲究实效地） about his fear of aliens in an interview for the Discovery Channel.

"If aliens visit us, the outcome would be much as when Columbus landed in America, which didn't turn out well for the Native Americans," he said. "Such advanced aliens would perhaps become nomads⁷（游牧民，流浪者） , looking to conquer and colonize⁸ whatever planets they can reach."

But Hawking says he is still hopeful for the future of humanity.

"I'm an optimist," he told Big Think. "We have made remarkable⁹ progress in the last hundred years. But if we want to continue beyond the next hundred years, our future is in space."

Getting to another planet will prove a challenge, not to mention colonizing¹⁰ it for humanity. University of Michigan astrophysicist（天体物理学家） Katherine Freese told Big Think that "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.