According to a new study, alien civilizations were plenty but they’re probably extinct, but the findings could hold clues as how could we, humans, extend the civilization we have. The findings are published in the journal Astrobiology.

Even when is estimated how many stars exist, it is still unknown how many of those planets have potentially harbored life, how often life might evolve and spawn intelligent beings and how long lasted those civilizations before extinction, said Adam Frank, lead researcher and University of Rochester professor. He added that thanks to NASA’s Kepler satellite and other searchers, they know that roughly one-fifth of stars have planets in zones where temperatures could support life as we know it.

This image, taken by the Hubble Space Telescope, shows a nearby dwarf galaxy called Leo A. Credit: NASA

‘Are we the only technological species that has ever arisen?’

In order to give an answer to the question, Frank and his co-author Woodruff Sullivan of the University of Washington pictured a universe where humanity on Earth is the only survival. Applying this to the number of known stars, they saw a probability of one in 10 billion trillion, or just one in 60 billion if in the Milky Way alone, which is a very small chance of humanity being alone in the universe.

Frank noted that due the universe’s vast distances and the uncertainty behind the length of civilizations, there are small chances of having communication with any living entity out there.

Many alien civilizations may have existed

It is very likely that other intelligent species have evolved before us, and even one chance in a trillion implies that humanity on Earth has happened about 10 billion other times over cosmic history, Frank explained.

“Our results imply that our evolution has not been unique and has probably happened many times before,” Frank said.

A civilization must last more than Earth’s 10,000 over the 13-billion-year existence of the universe, otherwise is likely that they have become extinct. Still, Frank noted that the fact that humans have been alive for roughly 10,000 years doesn’t really mean that other societies would last that long or maybe much longer.

Knowing that evolution probably has happened many times before, humanity can investigate the matter of survival using simulations to know what promotes or prevents lasting civilizations. However, NASA is still looking to find alien life, and there are high hopes for the probe they are set to soon launch to Jupiter.

Source: Astrobiology