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What methods can be used to identify subsurface oceans on the five largest moons of Uranus: Ariel, Umbriel, Titania and Oberon, and Miranda? This is what a presented at the 56th Lunar and Planetary Science Conference () hopes to address as a team of scientists from NASA's Jet Propulsion Laboratory (JPL) investigated potentially using radio science on the , which was designated as a high priority Flagship-class mission by the 2023–2032 Planetary Science Decadal Survey.

For the study, the researchers used a combination of interior modeling for the five largest Uranian moons and computer models regarding how UOP could conduct gravity and radio science (GRS) studies during its potential mission.

The goal was to ascertain the statistical likelihood of identifying subsurface oceans within Uranus' five largest moons while building off past studies that helped identify subsurface oceans on Titan, Enceladus, and Europa. This included using a planetary body's wobble, called librations, as it orbits its planet to analyze its internal characteristics, specifically a subsurface ocean.

The study notes, "Combining radio science with optical data, we find that in some cases it is possible to detect the libration amplitudes with accuracies close to those required to reveal the presence of a global ocean, which are on the order of few tens of meters for thin shells. If the moons have thicker shells, the detection of a deep ocean from libration measurements is unlikely."

As noted, UOP was identified as a high priority Flagship-class mission by the and is currently slated to launch sometime in the 2030s with an arrival at Uranus in the 2040s.

Along with the radio science experiments, UOP is currently slated to carry a suite of instruments designed to study Uranus' magnetic field, energetic particles, plasma and infrared spectrometry, and traditional imaging cameras. Additionally, UOP is currently slated to harbor an atmospheric probe designed to sample Uranus' atmosphere to gain greater insight into its structure and composition.

One of the reasons that UOP is being pursued is because the only spacecraft to visit Uranus and its moons is NASA's Voyager 2, which flew past the Uranian system in January 1986. During this brief flyby, Voyager 2 captured incredible and up-close images of Uranus and its many moons, specifically its five largest moons: Ariel, Umbriel, Titania and Oberon, and Miranda.

Despite this brief encounter and limited dataset, these moons continue to be studied by scientists today, comparing cryovolcanism from the dwarf planet Ceres to potential cryovolcanism on Umbriel and Oberon.

As its name implies, the is a once-a-decade meeting of the top planetary scientists with the goal of prioritizing science missions and objectives for the next decade. Along with selecting UOP as a high priority Flagship-class mission, the survey also designated the Enceladus Orbilander as a second-highest priority, given Enceladus is a prime target for astrobiology research with its subsurface ocean.

Despite UOP being years away from launching, and even longer until it arrives at Uranus, studies like this can help scientists, engineers, and the next generation of students develop key scientific questions and objectives for the long term. This includes asking whether Uranus' five largest moons harbor subsurface oceans like Europa and Enceladus despite being so far from the sun.

What processes could be responsible for these oceans existing, and could we find life down there? These questions, and more, are what will drive UOP to accomplish the next phase of scientific exploration into the next decade, and beyond.