Title: New Analysis Reveals Increased Potential for Finding Liquid Water and Life on Exoplanets
Subtitle: Study suggests oceans hidden beneath frozen surfaces could expand the search for habitable worlds in the galaxy
Lyon, France – A groundbreaking analysis presented at the Goldschmidt geochemistry conference in Lyon indicates that the likelihood of discovering Earth-like exoplanets with liquid water has significantly increased. The research suggests that geological conditions beneath the surface of some planets may be suitable for liquid water, even if the surface is frozen, providing potential environments where life could develop.
Lead researcher Dr Lujendra Ojha from Rutgers University in New Jersey shared the findings, stating, “We know that the presence of liquid water is essential for life. Our work shows that this water can be found in places we had not much considered. This significantly increases the chances of finding environments where life could, in theory, develop.”
The study focused on planets orbiting M-dwarfs, a common type of star that is smaller and colder than our Sun. These small stars constitute 70% of the stars in our galaxy. Previous estimations suggested that approximately one rocky planet out of every 100 stars would have liquid water. However, the new model suggests that if the conditions are right, this ratio could approach one planet per star, meaning that the chances of finding liquid water and potential life are a hundred times higher than initially anticipated.
Explaining the heat generation that could facilitate liquid water beneath a frozen surface, Dr Ojha noted, “Even though Earth’s greenhouse gases are currently keeping our surface water stable, if they were lost, the average global surface temperature would drop to about -18 degrees Celsius, causing surface water to freeze. However, radioactivity deep within the Earth can still generate enough heat to keep water liquid in certain areas, as observed in Antarctica and the Canadian Arctic. There is even some evidence to suggest that this phenomenon may be occurring in Mars’ south pole.”
Dr Ojha went on to mention the presence of underground lakes on moons such as Europa and Enceladus, despite their frozen surfaces. These underground reservoirs are sustained by the gravitational effects of the large planets they orbit, similar to the Moon’s impact on tides but on a much more significant scale. Scientists consider these moons of Jupiter and Saturn as promising candidates for discovering life within our own Solar System.
The implications of this research extend beyond our solar system. The earliest mission to an “ice world” type moon, NASA’s Europa Clipper, is set to launch in 2024, targeting Europa’s exploration by 2030.
Commenting on the study, Professor Abel Méndez, Director of the Planetary Habitability Laboratory at the University of Puerto Rico, acknowledged the importance of discovering oceans hidden beneath ice sheets to expand the potential for habitable worlds in our galaxy. Méndez added that future telescopes must be devised to detect these habitats.
The research underlying the presentation was recently published in the peer-reviewed journal Nature Communications. The Goldschmidt Conference, a joint congress of the European Association of Geochemistry and the Geochemical Society, is currently underway in Lyon and is expected to attract nearly 5000 delegates.
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