NEW YORK — Are we alone in the universe? It’s an age-old question which has kept scientists and science-fiction fans guessing throughout human history. A new study is now placing bets on whether “E.T.” is real — and the odds say we are not alone.
David Kipping, assistant professor in Columbia University’s Department of Astronomy, says a study of how Earth developed can be used to figure out if alien worlds can also support life. Looking at the earliest signs of life on Earth and how humans evolved, Kipping says the odds that life is common throughout the universe are much better than the odds against it.
“In this study it’s possible to actually quantify what the facts tell us,” Kipping said in a statement.
The Columbia researcher looked at four possible outcomes for life in the cosmos:
- Life is common and often develops intelligence
- Life is rare but often develops intelligence
- Life is common and rarely develops intelligence
- Life is rare and rarely develops intelligence
“A key result here is that when one compares the rare-life versus common-life scenarios, the common-life scenario is always at least nine times more likely than the rare one,” Kipping explained.
Another Earth? It’s Possible
The study was based on evidence that life on Earth began to emerge within 300 million years of the planet’s oceans forming. Kipping believes that if there are other planets in the universe that share Earth’s evolutionary track record then life should have no problem existing there too.
The real question is will that life be intelligent like us? The study says that answer is a little harder to be certain of, but the research put the odds at 3:2 odds in favor of intelligent aliens. The professor explains that human evolution was actually a very rare event, making it difficult to figure out if it could happen elsewhere.
“If we played Earth’s history again, the emergence of intelligence is actually somewhat unlikely,” Kipping said. “The analysis can’t provide certainties or guarantees, only statistical probabilities based on what happened here on Earth.”
Those probabilities put the chances of intelligent aliens at about 50:50. Despite the results, Kipping adds that the case for basic life on other worlds is very strong and the human race shouldn’t give up on the hope that someone out there may be able to talk to us one day.
“The case for a universe teeming with life emerges as the favored bet. The search for intelligent life in worlds beyond Earth should be by no means discouraged.”
The study was published in the Proceeding of the National Academy of Sciences.