As far as humanity knows, Earth is the only planet that has life. Now, a new study led by Dr. Stephanie Olson of the University of Chicago proposes that Earth might not necessarily be the best-suited planet for life, as Newsweek reports. “This is a surprising conclusion,” Olson said in a statement. “It shows us that conditions on some exoplanets with favorable ocean circulation patterns could be better suited to support life that is more abundant or more active than life on Earth.”
The researchers’ findings are certainly surprising. Earth, as it has been for billions of years, seems like the most ideal place for life to exist. The blue marble has lucked out when it comes to the conditions needed to foster life. For hundreds of years, philosophers and scientists have wondered if Earth might be an anomaly in the universe. The new study suggests that the answer might be no.
Spin and Splash
Since astronomers started searching in earnest, around 4,000 exoplanets have popped up on the radar. Unfortunately, many of these are inhospitable to the type of life found on Earth. However, Olson and her colleagues’ new model posits that planets with water, substantial atmosphere, and slow rotations could beat Earth in the life department. Still, there’s a catch. Most of these planets are tens or hundreds of light-years away. So it’s difficult to know which, if any, of these worlds exhibit the right conditions for life.
According to the study, atmospheric, slow-spinning, watery worlds are more likely to harbor life because of how those characteristics affect the planet as a whole. Movement in an ocean is integral to stirring up the ingredients for life. On Earth, life likely arose in the sea. So, it’s a safe bet that life elsewhere might have done the same.
What makes these proposed worlds better suited for life than Earth is a thicker atmosphere. This feature means higher surface pressure. Couple that with slower planetary rotations and water-to-shore dynamics and an exoplanet has the perfect ingredients for ocean upwelling. This transports nutrients and, in turn, increases the chances that a life-forming cocktail might stir up.
Are We Alone?
Thanks to the massive distance between Earth and these exoplanets, it will be very difficult for astronomers to detect worlds that have the tell-tale signs of life. However, new, more powerful telescopes that are currently in the works could help find planets with water and/or other favorable conditions for life.
For instance, NASA’s James Webb Space Telescope (the successor to Hubble) is set to launch in 2021. It will provide a closer look at Earth’s exoplanet neighbors. This better view could clue scientists in to whether or not these exoplanets have ideal conditions for life.
Mathematically, the probability that life exists beyond Earth is pretty high due to the mind-boggling number of galaxies exoplanets that are out there. However, if Olson and her team’s model is correct, the chances of finding life off-planet just got a lot better. With each technological advance, humanity comes closer to answering the question: Are we alone?