Are We Close to Finding Extraterrestrial Life?

 The topic of many of my articles involves the search for extraterrestrial life. I look at what conditions are needed to support life on Earth and see if such environments exist elsewhere. For example, we found seasonal variations of methane in the Martian atmosphere. On our planet, methane is almost exclusively associated with life. I’ve written about astronomers’ efforts to find and study planets orbiting other stars to determine if they orbit in the habitable zone where water can exist on the surface. On Earth, virtually wherever we find water, we find living creatures. That may only be microbial life, such as that found in acidic hot springs or water trapped far below the surface, but life nonetheless.

Even if we only find such microbial life, that would be an astounding discovery. It would tell us that life can develop in locations other than Earth which at the moment is the only location in the universe where life is known to exist.

Recently, a newsletter called The Conversation ran an article in which the authors polled astrobiologists and other scientists on their belief in extraterrestrial life. The Conversation is an online source of articles written by researchers and academics across all disciplines. It gives them a platform to present their work to the public. We often read articles that say finding extraterrestrial life is “only a matter of time”, or “we are close to finding alien life.” And yet, we still await that discovery.

Exoplanets in their star's habitable zone. Are we close to discovering exo-life?

In 2024, three researchers – Peter Vickers, a Professor in Philosophy of Science at Durham University, Henry Taylor an Associate Professor in the Department of Philosophy at the University of Birmingham, and Sean McMahon, of the University of Edinburgh – did surveys, polling a number of astrobiologists, those scientists who study and look for the chances of life elsewhere, and scientists in other fields on their beliefs of the existence of alien life. They asked about their beliefs, based on all the research to date, of the existence of basic lifeforms, i.e. microbial life, complex forms, i.e. multicellular life, and intelligent extraterrestrial life.

Altogether, they received responses from 521 astrobiologists and 534 non-astrobiologists. Of the astrobiologists, 86.6% said they “agree” or “strongly agree” that extraterrestrial life, at least at the basic level, exists elsewhere. Less than 2% disagreed with the sentiment and 12% claimed to be neutral on the possibility. Of the non-astrobiologists, 88.4% also marked “agree” or “strongly agree” with the question. Scientists who don’t study the possibility of extraterrestrial life are not more skeptical than those who do. The authors of the survey felt that to be a rather significant result.

The survey asked about each level of life – basic, complex, and intelligent – separately. The results when asked specifically about whether “intelligent” aliens exist were not quite as optimistic. Only 67.4% of astrobiologists and 58.2% of other scientists agreed, still more than half. Only 10.2% of astrobiologists disagreed with that statement.

This survey cannot in any way offer proof of life elsewhere, but the preponderance of scientific research and evidence leads most scientists, at least in these fields, to accept the likelihood. Astronomers estimate that in our galaxy alone a trillion extrasolar planets, those orbiting other stars, exist. They further estimate that billions of Earth-like planets orbit in the habitable zone of their parent star.

Life on Earth is proving to be far more robust than we previously thought. Microbes called extremophiles can survive in all kinds of environments once thought unable to support any kind of life. Creatures called tardigrades, or water bears, have even been shown to survive in airless, radiation-filled outer space beyond our planet. I suspect that the existence of such extremophiles that survive in these hazardous or toxic locations is a large part of the thought processes of these scientists.

Perhaps it really is only a “matter of time” before we discover alien life forms. And. Some scientists say we may not even recognize alien creatures as living at first. We have no idea if “life as we know it” is all that there can be.

 

Each month, I write an astronomy-related column piece for the Oklahoman newspaper. After it is published there, I post that same column to my blog page.

This is reprinted with permission from the Oklahoman and www.Oklahoman.com.