There's always been two possibilities when it comes to extra-terrestrial life: either it exists or it doesn't.
However, a recent paper published in Astrobiology, has ran with new discoveries of exoplanets - AKA any planet that orbits a star other than the Sun - to estimate the likelihood that other advanced civilisations having existed apart from humans.
The paper's author, Adam Frank, says that the human race is unique if the chances of an advanced civilisation functioning on a planet is less than one in around 10 billion trillion.
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Remember these toys? They probably weren't toys. Credit: PA
"One in 10 billion trillion is incredibly small." Frank said in a 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 10 billion other times over cosmic history [owing to the estimated number of stars and planets in the universe]!"
This probability was influenced by the Drake Equation. Not, as you might think, a calculation proposed by the Canadian rapper, but a "probabilistic argument used to arrive at an estimate of the number of active, communicative extraterrestrial civilizations in the Milky Way galaxy."
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Frank and his colleague Woodruff Sullivan translated the equation into simple terms in the paper. The number of advanced civilisations equal the number of habitable planets in the universe multiplied by the chances of a species emerging on one of these planets.
It's a bit of a brain-lag, so here's the picture to give a bit of context.
It goes without saying that the likelihood of other-worldly life cannot be proven, but by presuming humankind to be a lone wolf, Frank and Sullivan were able to provide a "pessimistic limit."
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"From a fundamental perspective, the question is 'has it ever happened anywhere before?'" Frank said. "Our result is the first time anyone has been able to set any empirical answer for that question and it is astonishingly likely that we are not the only time and place that an advance civilization has evolved."
If you're not still scratching your head and are actually super-glued to this story, you can watch this TED Talk on the Drake Equation:
Words by Josh Teal
Featured Image Credit:Topics: Alien