On multiple occasions, he has warned of the likelihood that alien species will act like colonialists if they ever visit Earth, likening extraterrestrials’ tendencies to our own human behavior.
One day we might receive a signal from a planet like this, but we should be wary of answering back. Meeting an advanced civilization could be like Native Americans encountering Columbus. That didn’t turn out so well,” he has said.

Stephen Hawking has also warned that it’s only a matter of time until Earth is destroyed. “Although the chance of disaster to planet Earth in a given year may be quite low, it adds up over time, and becomes a near certainty in the next 1,000 or 10,000 years,” he said in November.

As a result, he has advocated colonizing both the moon and Mars.

Keeping up with his warnings, Hawking warns in a forthcoming documentary — called Stephen Hawking: Expedition New Earth — that humans should make their exodus from the planet within the next century if they have any hope of surviving. According to the BBC, which is releasing the feature this summer, Hawking discusses his assertion that “the human race only has one hundred years before we need to colonize another planet.”

In the film, set to be released next month, Hawking details why this will be necessary, noting threats facing the planet including epidemics, asteroid strikes, and climate change.

The BBC documentary includes Stephen Hawking and other academics and aims to “… find out if and how humans can reach for the stars and move to different planets,” according to the British network.

BBC asserts Hawkings’ seemingly outlandish predictions and advice about leaving Earth are actually well-founded.

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