The human race has made some pretty big steps in exploration in the last few decades, but we have yet to find anything even close to advanced life.
But, although we haven’t found it, two scientists believe it is ‘virtually impossible’ that intelligent life hasn’t already existed elsewhere – and they’ve discovered an equation to prove it.
Adam Frank and Woodruff Sullivan recently published a study in Astrobiology which takes new discoveries of exoplanets (AKA. planets that orbit a star other than the Sun) to estimate the likelihood that other advanced civilisations have existed.
Basically, the study argues that the human race is only unique if the chances of intelligent life functioning on a planet is less than one in around 10 billion trillion.
Adam Frank, professor of physics and astronomy at the University of Rochester and co-author of the paper, told Science Daily:
One in 10 billion trillion is incredibly small.
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.
The probability was influenced by the Drake Equation – a ‘probabilistic argument used to arrive at an estimate of the number of active, communicative extraterrestrial civilizations in the Milky Way galaxy.’
In simpler terms, the number of advanced civilisations equal the number of habitable planets in the universe, multiplied by the chances of life on one of those planets.
It’s a tad complicated to understand, so here’s a picture:
Don’t get too exited though. Sullivan points out that the full Drake Equation doesn’t confirm that other intelligent life exists at this very moment:
The universe is more than 13 billion years old. 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.
So even if there is life out there, the chances of us finding it are pretty slim.
Let’s hope that if aliens do exist, they’re smarter than we are and find us first.