Do Aliens Exist? Scientists Calculate Likelihood Of Life Existing Elsewhere In The Universe
Is the truth out there?
The question of whether life exists elsewhere in the universe is one that has puzzled humankind for centuries.
For the past 50 years, this has been summed up by the Drake equation, which provides an estimate of the probability of life in our galaxy.
But as new stars and planets have been discovered as we’ve delved deeper into the universe, the famous formula has become outdated, say scientists.
In a study, published in Astrobiology, scientists have revealed a new equation that suggests intelligent life almost certainly exists – even if we never find out.
It found that roughly one-fifth of stars have planets in ‘habitable zones’ – meaning, according to probability, humankind is unlikely to be the universe’s first civilisation.
“The question of whether advanced civilisations exist elsewhere in the universe has always been vexed with three large uncertainties in the Drake equation,“ said Adam Frank, professor of physics and astronomy at the University of Rochester and co-author of the paper.
"We’ve known for a long time approximately how many stars exist. We didn’t know how many of those stars had planets that could potentially harbour life, how often life might evolve and lead to intelligent beings, and how long any civilisations might last before becoming extinct.”
"Thanks to NASA’s Kepler satellite and other searches, we now know that roughly one-fifth of stars have planets in 'habitable zones,’ where temperatures could support life as we know it. So one of the three big uncertainties has now been constrained.”
“Of course, we have no idea how likely it is that an intelligent technological species will evolve on a given habitable planet,” Frank added.
He said that by using the new method they can tell exactly how low the probability would have to be for us to be the only civilisation the universe has produced.
“One in 10 billion trillion is incredibly small,” he told Science Daily. “To me, this implies that other intelligent, technology producing species very likely have evolved before us.”
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