Stephen Hawking has tackled the mysteries of the universe his entire life.
Now the world-renowned scientist has some new things to say about a potential alien invasion.
"If aliens visit us, the outcome could be much like when Columbus landed in America, which didn’t turn out well for the Native Americans," Professor Hawking told El País .
"Such advanced aliens would perhaps become nomads, looking to conquer and colonise whatever planets they can reach," he said.
The physicist, who has suffered from motor neurone disease since his twenties, explained that the existence of aliens is beyond doubt.
"To my mathematical brain, the numbers alone make thinking about aliens perfectly rational. The real challenge is to work out what aliens might actually be like."
He also explained that the best chances for the survival of the human race is to find a new home on another planet.
"There's an increasing risk that a disaster will destroy Earth," Prof Hawking explains.
Illustrated by Elliot Salazar.: Stephen Hawking's life has been one of triumph. It's been so triumphant, in fact, that it's the subject of a new film, The Theory of Everything, starring Eddie Redmayne and Felicity Jones. (This author can tell you it's not only one of the greatest movies she's seen in a long time, but one so beautifully scored it will change the texture of your skin.) As you prepare to experience the film, it's important to reflect on what makes Hawking himself so remarkable. Yes, it's that he's brilliant. Yes, it's that he's exceeded the wildest expectations about his motor neuron disease and quality of life. But, it's also because of the attitude he maintains and perspective he provides. Ahead, in honor of his birthday, 15 of his most inspirational quotes. 15 Stephen Hawking quotes that will change your life "I therefore want to raise public awareness about the importance of space flight. I have learnt not to look too far ahead, but to concentrate on the present.
"I have so much more I want to do."
In July, Britain's most famous scientist helped to launch Breakthrough Listen , a 10-year, £64million project funded by US-based Russian billionaire Yuri Milner.
Mr Milner’s team will scan the skies for alien broadcast signals, searching the entire Milky Way and 100 nearby galaxies.
Professor Hawking, 73, said at the Royal Society in London: “Somewhere in the cosmos, perhaps, intelligent life may be watching these lights of ours aware of what they mean.”