Why haven’t we seen aliens? Chris Anderson at TED2012

Posted by:

Photo: James Duncan Davidson

TED Curator Chris Anderson talks about the TED-Ed project — a major initiative to bring TED to school and education outside of the classroom. As part of that, he tries his own talk. With a pre-recorded animation (by Andrew Park) playing behind him, he asks a question that has bugged him ever since he was a kid.

“Why can’t we see evidence of alien life?”

Intuitively, there should be a tremendous number of inhabited planets, but we see no signs of them. The Kepler mission has discovered hundreds of planets around other stars. Extrapolating to the galaxy, and assuming just one in a thousand could harbor life, there, “Could be 15 million life-harboring planets.”

And the Earth didn’t form till 10 billion years after the Big Bang. If just a few planets had produced civilizations with technology, they would have had at least millions of years head start. They should have spread across the galaxy, or created sky-spanning works of art. “We should have discovered them.”

There are dark possibilities for why we might not have seen them. A single civilization might have already taken over, banning radio broadcasts for fear of competition, and eliminating any new civilizations.

Maybe intelligence is rare? Maybe we really are the first. “Or perhaps all civilizations carry the seeds of their own destruction with the inability to control the technologies that they create.”

But we’re not working very hard to find them. Only a tiny fraction of stars have been properly checked out. Or maybe they communicate using technologies beyond us.

Or maybe we’re looking at the wrong scale. “What if intelligent life is discovered that actually life is all about beautiful patterns of info interacting with each other in beautiful ways … What if biological life is just a passing phase?”

We’re trying. SETI has just this week opened up its data so the world can join the search. Other people are trying to create life from scratch in the laboratory.

So here’s Anderson’s final question: “Is the universe teeming with life, or is it just us? Both answers are awe-inspiring. Even if we’re alone, the very fact that we can think and dream and ask these questions might turn out to be one of the most important facts of the universe.”

And his final point, “The quest for knowledge never gets dull. The more you learn the more thrilling this world seems. Please, stay curious.”