Stephen Hawking, perhaps the world’s best-known cosmologist, theoretical physicist and author, has once again issued a warning on Earth’s search for extraterrestrial life, repeating his advice that humans should think twice before we make contact.
Dr. Hawking expressed his concerns on a newly released 25-minute online film called "Stephen Hawking’s Favorite Places," in which he takes viewers on a virtual tour of his five favorite places in the universe. As the camera peers into black holes and looks at star systems on the program, Hawking cautions that while life might be out there, it might not be a pleasant thing for humanity to discover.
“We should be wary of answering back,” Hawking said, echoing sentiments he has previously expressed. “Meeting an advanced civilization could be like Native Americans encountering Columbus — that didn’t turn out so well.”
Although Hawking has long supported the search for life outside our own planet, he has remained cautious through the years, repeatedly warning that if we encounter life elsewhere, there is a good chance that the life we encounter might not be the best kind of neighbor.
“We only have to look at ourselves to see how intelligent life might develop into something we wouldn’t want to meet,” Hawking told The Times of London in 2010, adding that:
“I imagine they might exist in massive ships, having used up all the resources from their home planet. Such advanced aliens would perhaps become nomads, looking to conquer and colonize whatever planets they can reach.”
Nevertheless, Hawking is an enthusiastic researcher, ever expressing curiosity in the possible worlds beyond our solar system.
In Stephen Hawking’s Favorite Places, released on the online platform Curiosity Stream, he brings viewers to the planet Gliese 832c, located about 16 light years away from our own planet in the constellation Grus. Currently, Gliese 832c is one of the best candidates to date for life outside of Earth.
“It’s a breathtaking sight, a super-Earth five times more massive than ours,” Hawking tells viewers.
There are various efforts underway in the search for life beyond this planet - ranging from NASA's Mars mission to the three-decade old Search for Extraterrestrial Intelligence (SETI) Institute in Mountain View, Calif.
Another recently launched initiative, sponsored in part by Hawking himself, is searching for signs of communication from outer space.
"There is no bigger question. It's time to commit to finding the answer – to search for life beyond Earth," said Hawking at the launch of the $100 million Breakthrough Listen project, though he remained cautious about contact with other civilizations.
Sponsored by Hawking, Facebook CEO Mark Zuckerberg, and Russian billionaire Yuri Milner, Breakthrough Listen project would send thousands of postage stamp sized nanobots through the universe, propelled by light.
While any civilization spotted could be thousands of years ahead of humans, in terms of technology and understanding, and therefore dangerous, Hawking is nevertheless interested in seeing just how much humanity can discover. And, he notes, we might need to look beyond our Earth for survival.
"The Earth is a wonderful place, but it might not last forever," Hawking at a Breakthrough Listen press conference this spring. "Sooner or later we must look to the stars. Breakthrough Starshot is a very exciting first step on that journey."
"The limit that confronts us now is the great void between us and the stars," he added. "But now we can transcend it, with light beams, light sails, and the lightest spacecraft ever built. Today we commit to this next great leap into the cosmos, because we are human and our nature is to fly."