A new study suggests that there are probably lots of alien civilizations that have come and gone.
As we reported recently, a new study claims that there are probably many alien civilizations out there, and there will probably be many more. But unfortunately, we’re not ever likely to encounter them.
The study, out of the University of Rochester, claims that based on data from the Kepler space telescope which reveals that about a fifth of stars have a planet in the habitable zone, there have probably been many alien civilizations throughout time based on simple probability — the odds of it not happening are just too minute.
“One in 10 billion trillion is incredibly small,” Adam Frank, professor of physics and astronomy at the University of Rochester and co-author of the paper, said in the statement. “To me, this implies that other intelligent, technology producing species very likely have evolved before us. Think of it this way. Before our result you’d be considered a pessimist if you imagined the probability of evolving a civilization on a habitable planet were, say, one in a trillion. But even that guess, one chance in a trillion, implies that what has happened here on Earth with humanity has in fact happened about a 10 billion other times over cosmic history!”
So surely that means that one day humans will encounter them? Well, actually probably not.
The problem is, humans actually haven’t been around that long — our civilization is only about 10,000 years old. That’s a tiny blip compared to the billions of years the universe has been here. There’s no telling how long our civilization will last, but considering how often extinction events happen, civilizations have probably sprung up many times before across the universe and were snuffed out in a short period of time, at least in terms of the vastness of the cosmos.
And since space is so huge, it makes reaching out to another civilization almost impossible. First of all, it would be like looking for a needle in a haystack, and secondly, communications — let alone transport — would take so long to cross those vast distances.
So while we may not technically be alone, and that’s an exciting thought, in more real terms we really are alone.
“The universe is more than 13 billion years old,” Woodruff Sullivan, who is from the astronomy department and astrobiology program at the University of Washington and co-authored the study, said in the statement. “That means that even if there have been a thousand civilizations in our own galaxy, if they live only as long as we have been around — roughly ten thousand years — then all of them are likely already extinct. And others won’t evolve until we are long gone. For us to have much chance of success in finding another ‘contemporary’ active technological civilization, on average they must last much longer than our present lifetime.
“Given the vast distances between stars and the fixed speed of light we might never really be able to have a conversation with another civilization anyway,” added Frank. “If they were 20,000 light years away then every exchange would take 40,000 years to go back and forth.”