Renowned physicist Stephen Hawking believes that if there are aliens out there in the universe, some might live on massive ships, on the prowl for... you guessed it. Us.
In a clip from the 2010 Discovery series "Stephen Hawking's Universe," Hawking suggests that if aliens used up all the resources on their home planet, they'd turn nomad in the search for more.
The aliens would come sniffing around other planets, like Earth, to conquer and colonize. They'd ransack our world to find new materials to build more ships, then move on.
That doesn't sound like good news for us.
Hawking's imagined aliens could have technological capabilities way beyond us mere Earthlings.
"Perhaps their capabilities would only be limited by how much power they could harness and control," the narrator of the documentary says. "And that could be far more than we might first imagine."
What if the aliens could collect the energy from an entire star?
The documentary proposes they might surround the sun with millions of mirrors and focus the power to one collection spot.
And what would they do with all that power? Build a porthole.
The porthole Hawking refers to is a wormhole, which, in theory, is a passage or shortcut through time and space, allowing long distance travel across the universe.
Our journey concludes with some haunting words: "Like us, [the aliens] probably would've evolved from species who are used to exploiting whatever they can."
Maybe we don't need to fear aliens after all. Aren't we depleting our world of resources already?
Let's hope we have some big ships to float around space when that happens.