The discovery of surprising methane deposits and evidence of geothermal activity on the dwarf planets Eris and Makemake has astronomers rethinking what lies beneath the icy surfaces of these distant celestial bodies.
The prevailing belief has been that dwarf planets in the outer reaches of the solar system are essentially composed of rocks, amorphous carbon, and volatile ices, and that they have remained cold since their formation. However, recent findings challenge this notion.
A team of researchers from the Southwest Research Institute, Lowell Observatory, and the University of Central Florida used the Webb Space Telescope to observe the presence of young methane deposits on the icy dwarf planets Eris and Makemake in the Kuiper Belt. This marks the first time that large-scale methane deposits have been discovered on these dwarf planets, pointing to the possibility of warm underground oceans.
The surface methane on Eris and Makemake is found to be younger than the original methane present since the formation of the solar system, indicating that the internal core temperature is rising. This suggests that there may be hydrothermal reactions occurring in the depths of these dwarf planets, producing new methane that reaches the surface through processes such as exhaust or even volcanism. The presence of a hot interior raises the possibility of liquid oceans existing underneath the icy surfaces, potentially making Eris and Makemake suitable for life.
The implications of these findings extend beyond just Eris and Makemake. The researchers note that a new model describing the formation and outgassing of methane on these dwarf planets also applies to Titan, a moon of Saturn. This suggests that if Titan, like Eris and Makemake, has the ability to form methane in its internal core with other gases, it could lead to life-inducing carbon chemistry emerging from within the planet.
The research has been published in the journal Icarus, providing new insights into the nature of our solar system’s outer regions and the potential for habitable environments in unexpected places.