Skip to main content

4 of Uranus’s icy moons could have liquid water oceans

When it comes to exploring planets in our solar system, most of the attention gets placed on those nearest to Earth which are easier to visit, and with powerful telescopes, we often observe the gas giants Jupiter and Saturn too. The more distant planets like Uranus and Neptune, however, are often overlooked and there’s growing support among planetary scientists for sending a mission there. Now, new evidence gives even more impetus for a mission to Uranus, with a recent study showing that four of the planet’s moons could host water.

Researchers from NASA’s Jet Propulsion Laboratory reanalyzed data from the Voyager 2 mission which passed Uranus in the 1980s to look at the five largest of its 27 moons: Ariel, Umbriel, Titania, Oberon, and Miranda. Using computer modeling of how porous the surfaces are, they found that four of these moons likely have liquid water oceans beneath icy crusts.

Uranus is surrounded by its four major rings and 10 of its 27 known moons in this color-added view that uses data taken by the Hubble Space Telescope in 1998. A study featuring new modeling shows that four of Uranus’ large moons likely contain internal oceans.
Uranus is surrounded by its four major rings and 10 of its 27 known moons in this color-added view that uses data taken by the Hubble Space Telescope in 1998. A study featuring new modeling shows that four of Uranus’ large moons likely contain internal oceans. NASA/JPL/STScI

The diagram below shows what the interiors of the five largest moons are thought to be composed of, with layers of ice, rock, and water. Even though Uranus and its moons are very far from the sun and therefore have very cold surface temperatures, there could be salty oceans present because they are insulated by a thick layer of ice and seem to have ammonia in them, which acts like an antifreeze. And in some cases, the moons could be warmed by internal heat mechanisms from their rocky mantles.

New modeling shows that there likely is an ocean layer in four of Uranus’ major moons: Ariel, Umbriel, Titania, and Oberon. Salty – or briny – oceans lie under the ice and atop layers of water-rich rock and dry rock. Miranda is too small to retain enough heat for an ocean layer.
New modeling shows that there likely is an ocean layer in four of Uranus’ major moons: Ariel, Umbriel, Titania, and Oberon. Salty – or briny – oceans lie under the ice and atop layers of water-rich rock and dry rock. Miranda is too small to retain enough heat for an ocean layer. NASA/JPL-Caltech

The insulating effect is similar to what is seen at the icy moons around Jupiter and Saturn, which are also thought to host oceans and are targets for studying habitability. There seem to be a wide range of places that could host water oceans, even if they are outside the habitable zone.

Recommended Videos

“When it comes to small bodies – dwarf planets and moons – planetary scientists previously have found evidence of oceans in several unlikely places, including the dwarf planets Ceres and Pluto, and Saturn’s moon Mimas,” said lead author Julie Castillo-Rogez of NASA’s Jet Propulsion Laboratory in a statement. “So there are mechanisms at play that we don’t fully understand. This paper investigates what those could be and how they are relevant to the many bodies in the solar system that could be rich in water but have limited internal heat.”

The research is published in the Journal of Geophysical Research.

Georgina Torbet
Georgina has been the space writer at Digital Trends space writer for six years, covering human space exploration, planetary…
Three tiny new moons spotted orbiting Uranus and Neptune
Neptune

Our solar system has a few new entries with the recent discovery of three moons of Uranus and Neptune. These ice giant planets are so far away that it is difficult to detect small moons orbiting them, especially when one of the recently discovered moons is the faintest moon ever discovered by a ground-based telescope.

Unlike Jupiter and Saturn, which both have a plethora of moons, Uranus is known to host 28 moons and Neptune just 16. That includes Uranus's new diminutive moon, which is just 5 miles across. Like Uranus' other moons, it will be named after a character from a Shakespeare plays, but a new name has not yet been chosen, so for now it is S/2023 U1.

Read more
SpaceX just launched a moon mission that could enter the history books
Intuitive Machines' Odysseus lander heads to the moon.

SpaceX successfully launched a commercial mission to the moon from the Kennedy Space Center in Florida in the early hours of Thursday morning.

A Falcon 9 rocket carried Intuitive Machines' Odysseus lander to orbit, setting it on course for a rendezvous with the lunar surface next week.

Read more
Saturn’s tiny moon, Mimas, hosts an unexpected ocean beneath an icy shell
An illustration of Mimas orbiting Saturn.

When looking for places that could potentially harbor life in our solar system, astronomers are increasingly interested in some of the moons of large gas giant planets. Saturn's moon Enceladus and Jupiter's moon Europa, for example, are both top targets of habitability research because even though they are far from the sun, they are thought to host liquid water oceans beneath a thick, icy crust. Now, a new moon may join these ranks, as researchers have found evidence of an ocean beneath the icy shell of Saturn's small moon Mimas.

Mimas film

Read more