Stephen Hawking: If aliens call, we should be 'wary of answering'

Physicist Stephen Hawking is more convinced than ever that humans are not the only intelligent life form in the universe.

Hawking details his quest to find alien life and takes viewers on a tour of his favorite places in the universe, in a newly released 25-minute film from CuriosityStream, an online video-on-demand platform.

In Stephen Hawking’s Favorite Places, the iconic science superstar notes in recent years, scientists found thousands of planets outside our solar system.

“Some are burning hells, gates of fire and lava, others are solid diamond made in deadly x-rays from a dying star, but some are more like home,” he said.

In the film, Hawking takes viewers on a trip around the universe in his own CGI spaceship. He stops on Gliese 832c, a planet that could be one of the closest habitable world candidates discovered so far.

“It’s a breathtaking sight, a super-Earth five times more massive than ours,” he said.

Hawking notes scientists have no way to know if the planet is habitable. In the film, he said it's possible the atmosphere is so thick that it smothers the surface in super heat and smog, or the gravity of its nearby sun could lock the planet's spin. So, one side is always facing the sun.

“But if the planet escapes such fates, the planet could have Earth-like temperatures with an abundant liquid water, and where there is water, there is very often life,” Hawking notes.

Hawking said his Breakthrough Listen Initiative, which uses sensitive radio telescopes to pick up potential signals from planets, is in the range of Gliese 832c.

He said one day we might receive a signal back from a planet like Gliese 832c.

“We should be wary of answering back,” he said.  “Meeting an advanced civilization could be like Native Americans encountering Columbus — that didn’t turn out so well.”

According to Hawking, the discovery of intelligent life would be the greatest scientific discovery in history.

“It would force us to change,” he said. “We would have to give up the idea that we are unique and start acting with more compassion and humility.”

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