Recent research led by planetary scientist Burkhard Militzer from the University of California, Berkeley, suggests the existence of vast layers of supercritical water beneath the atmospheres of Uranus and Neptune. This finding could transform the current understanding of these ice giants.
Advanced computational simulations indicate that these water layers may reach thicknesses of up to 8,000 kilometers, forming under extreme pressures approximately 60,000 times greater than Earth's atmosphere. This discovery, supported by data from the Voyager 2 spacecraft, could help explain the asymmetric magnetic fields of Uranus and Neptune and provide insights into the formation of similar planets in other star systems.
The NASA concept Uranus Orbiter and Probe plans future missions aimed at exploring the internal layers of these planets and their moons. Such missions could not only confirm existing theories but also open new avenues of study regarding the potential for habitable environments beyond Earth.
Simulations suggesting the presence of these oceans utilized machine learning to model atomic interactions under the extreme pressure and temperature conditions found on these planets. The results indicated that water separates from hydrocarbons like methane and ammonia, leading to stratified internal structures. This phenomenon aligns with gravitational data obtained by Voyager 2 in the 1980s.
Supercritical water layers would not behave like liquid water on Earth; instead, they would take on an intermediate form between gas and liquid due to high pressures. This characteristic is crucial for explaining the tilted and asymmetric magnetic fields of Uranus and Neptune, which contrast with the dipolar magnetic fields observed in Jupiter and Saturn.
Nasa has prioritized a mission to the Uranus system as part of its exploration plans for the next decade. The Uranus Orbiter and Probe concept includes sending an orbiter and an atmospheric probe to study both the planet and its moons.
The launch of this mission could occur before 2034, leveraging a planetary alignment that would allow for gravitational assistance from Jupiter to reduce travel time. This opportunity has been highlighted in NASA's decadal report on solar system exploration priorities.
The moons of Uranus, particularly Miranda, are also attracting scientific interest. This icy moon could host a subsurface ocean, similar to those found on Europa, a moon of Jupiter, and Enceladus, a moon of Saturn. Data collected during a mission to the Uranian system could provide key insights into potential habitable conditions in these environments.
The discovery of possible water layers on Uranus and Neptune is redefining the differences between ice giants and gas giants like Jupiter and Saturn. Understanding these internal structures could enhance existing models of planet formation and evolution both within and beyond the solar system.
Modern simulations, combined with historical data from missions like Voyager 2, have laid the groundwork for new research and potential space missions that could expand knowledge about ice giants and their potential to harbor environments similar to those found on exoplanets.