What can not finding life beyond Earth tell us about the universe? This is what a recent study published in The Astronomical Journal hopes to address as an international team of researchers investigated the statistical likelihood of not finding signs of life on future exoplanets surveys, specifically regarding Earth-like exoplanets. This study has the potential to help scientists and the public better understand the long-term implications of not finding life beyond Earth and how that could shape our view of our place in the cosmos.
For the study, the researchers used a common statistical method called a Bayesian framework to ascertain how many exoplanets could harbor life depending on the number of exoplanets that are determined to absolutely not harbor life. In the end, the researchers concluded that for every 40 to 80 exoplanets that were found to definitely not harbor life, then less than 10 to 20 exoplanets could absolutely harbor life.
"It's not just about how many planets we observe – it's about asking the right questions and how confident we can be in seeing or not seeing what we're searching for," said Dr. Daniel Angerhausen, who is a Staff of Professorship for Exoplanets and Habitability at ETH Zurich and lead author of the stidy. "If we're not careful and are overconfident in our abilities to identify life, even a large survey could lead to misleading results."
This study comes as confirmed the existence of almost 5,900 exoplanets, with 217 of them being designated as terrestrial (rocky) and 1,741 being designated as super-Earths. Along with providing their statistical analysis, the researchers note this study could help future telescopes whose missions will be to identify Earth-like exoplanets, specifically the Large Interferometer for Exoplanets (LIFE) and the Habitable Worlds Observatory (HWO).
What new insights into not finding life beyond Earth will researchers make in the coming years and decades? Only time will tell, and this is why we science!
As always, keep doing science & keep looking up!
Sources: The Astronomical Journal, EurekAlert!
Featured Image: Artist's illustration of an Earth-like exoplanet. (Credit: NASA Ames/SETI Institute/JPL-Caltech)
