In a new paper, planetary researchers from Texas A&M University and the University of Washington introduce a new thermodynamic concept called the centotectic and investigate the stability of liquids in extreme conditions — critical information for determining the habitability of icy moons and ocean exoplanets.
The surface of Europa looms large in this newly-reprocessed color view; image scale is 1.6 km per pixel; north on Europa is at right. Image credit: NASA / JPL-Caltech / SETI Institute.
The exploration of icy ocean worlds represents a new frontier in planetary science, focusing on understanding the potential for these environments to support life.
The new research addresses a fundamental question in this field: under what conditions can liquid water remain stable on these distant, frozen bodies?
By defining and measuring the cenotectic, the absolute lowest temperature at which a liquid remains stable under varying pressures and concentrations, the authors provide a critical framework for interpreting data from planetary exploration efforts.
The study combines their expertise in cryobiology, with the expertise in planetary science and high-pressure water-ice systems.
Together, they developed a framework that bridges disciplines to tackle one of the most fascinating challenges in planetary science.
A 2016 artist’s concept of the Europa Clipper spacecraft. The design is changing as the spacecraft is developed. Image credit: NASA / JPL-Caltech.
“With the launch of NASA’s Europa Clipper, the largest planetary exploration mission ever launched, we are entering a multi-decade era of exploration of cold and icy ocean worlds,” said Dr. Baptiste Journaux, a planetary scientist at the University of Washington.
“Measurements from this and other missions will tell us how deep the ocean is and its composition.”
“Laboratory measurements of liquid stability, and notably the lowest temperature possible (the newly-defined cenotectic), combined with mission results, will allow us to fully constrain how habitable the cold and deep oceans of our Solar System are, and also what their final fate will be when the moons or planets have cooled down entirely.”
“The study of icy worlds is a particular priority for both NASA and ESA, as evidenced by the flurry of recent and upcoming spacecraft launches,” said Dr. Matt Powell-Palm, a plaentary scientist at Texas A&M University.
“We hope that Texas A&M will help to provide intellectual leadership in this space.”
The paper was published on December 18, 2024 in the journal Nature Communications.
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A. Zarriz et al. 2024. On the equilibrium limit of liquid stability in pressurized aqueous systems. Nat Commun 15; doi: 10.1038/s41467-024-54625-z
