In a groundbreaking study, NASA has unveiled a revelation that expands the search for extraterrestrial life. Researchers have identified 17 exoplanets positioned beyond our solar system that might boast subsurface oceans beneath their icy exteriors. The intriguing aspect lies in the possibility of periodic eruptions, resembling geysers, breaking through the frozen crusts of these distant worlds.
The research, conducted by scientists at NASA’s Goddard Space Flight Center, included a meticulous analysis of geyser activity on these exoplanets. Remarkably, two of these celestial bodies are within observational reach of telescopes, presenting an unprecedented opportunity to witness these icy eruptions. This discovery holds paramount significance as the subsurface oceans on these planets could harbor life, given the presence of essential components such as an energy source and the necessary elements and compounds for biological processes.
Despite uncertainties regarding the exact composition of these exoplanets, earlier studies estimating surface temperatures indicate that they are considerably colder than Earth. Moreover, despite their similarity in size to our planet, they exhibit lower density.
Internal Heating Mechanisms
Lynnae Quick from NASA’s Goddard Space Flight Center emphasized, “Our analyses predict that these 17 worlds may have ice-covered surfaces but receive enough internal heating from the decay of radioactive elements and tidal forces from their host stars to maintain internal oceans.”
Essentially, while the host stars may not provide the requisite warmth to keep surface water in liquid form, internal processes such as the gravitational interaction with their “sun” and the radioactive decay of heavy elements within their cores could generate enough heat to sustain subsurface oceans. This internal heating, as Quick explained, could result in cryovolcanic eruptions resembling geyser-like plumes.
The study drew inspiration from the geyser activity observed on two of Jupiter’s moons, Europa and Enceladus. Notably, the research identified Proxima Centauri b and LHS1140 b as particularly promising candidates for having oceans relatively close to the surface.
Quick noted, “Telescopes are most likely to detect geological activity on these planets,” emphasizing the potential for cryovolcanic eruptions hundreds to thousands of times more intense than Europa’s. Future observations will involve capturing the emission spectra of light passing through these exoplanets’ atmospheres, aiming to decipher whether chemicals and molecules from cryovolcanic activity could harbor signs of life in the cold depths of these distant worlds. Published in October in The Astrophysical Journal, this research marks a significant stride in our exploration of the cosmos.