"One day, we might receive a signal from a planet like this,"
Hawking said, referring to the potentially habitable alien planet Gliese 832c. "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 added in 2016 during the documentary "Stephen Hawking's Favorite Places," which streamed on the CuriosityStream video service.