A new study has revealed that Uranus’ four largest moons may harbor salty oceans beneath their surfaces.
Taking a fresh look at 40 years of data from NASA’s Voyager 2 spacecraft, scientists have discovered that Uranus’ furthest orbiting moons Titania and Oberon are 50 kilometers below the surface of the ocean, and Ariel and Umbriel are 30 kilometers below the surface. It is said that there is a possibility that it is harboring the sea.
New research explains how Uranus moons’ persistent internal heat and a few chemicals can create oceans despite the solar system’s harsh external environment.
Planetary scientist Julie Castillo-Roges of NASA’s Jet Propulsion Laboratory, who led the research, told Space.com on the 5th (local time), “If you find an ocean on a moon of Uranus, the presence of oceans in our solar system is universal, and it is likely that oceans in other solar systems will also be found.” will be more likely to exist.”
In the early days of the Solar System, Uranus’ five largest moons—Titania, Oberon, Ariel, Umbriel, and Miranda—would have harbored oceans ranging in depth from 100 to 150 kilometers, the researchers said. “If the moons were subjected to the planet’s long-term heating, they could have maintained a thick ocean,” explains Castillo-Roges.
For example, Jupiter’s moon Europa and Saturn’s Enceladus harbor huge subterranean oceans that warp their internal structures and ice shells in response to their parent planet’s powerful gravity. Scientists believe this tidal heat helps keep the satellite’s groundwater in a life-friendly liquid state.
But Uranus’ gravity is much weaker than that of Saturn or Jupiter, so even the oceans on the planet’s four largest moons “would be mostly frozen by now,” Castillo-Rogges added.
To better understand how Uranus’ largest moons evolved, the research team built a model by collecting results from NASA missions that studied other ocean worlds.
These include Saturn’s moon Enceladus as seen by the Cassini mission, the dwarf planet Ceres as revealed by the asteroid probe Dawn, and Pluto’s largest moon Charon as seen by New Horizons during a historic Pluto flyby in 2015. etc. are included.
“It is possible that Uranus’ moons harbor shallow oceans with high salt concentrations,” the researchers said. This may be due to some internal heat left over from the earliest days of the satellite and a significant amount of ammonia that helps keep the water in liquid form even at very low temperatures.
Researchers estimate that oceans on Uranus’ moons contain about 150 grams of salt per liter of water. By comparison, Utah’s Great Salt Lake is twice as salty, but life is still thriving in and around it.
But scientists are still not sure if Uranus’ fifth largest moon, Miranda, harbors an ocean. While previous research has hinted at hidden oceans to account for the intriguing charged particles that have flown into space, newer research suggests that Miranda is so small that the inner ocean likely froze millions of years after it formed.
So far, Uranus has only been briefly visited by Voyager 2 in January 1986. Voyager 2 discovered 10 new moons and two new rings around the icy planet. Uranus could get more attention in the not-too-distant future. It turns out that while the most common in the galaxy are icy planets, they also belong to many of the least understood secrets.
NASA is currently developing a planetary exploration mission called the Uranus Orbiter and Probe (UOP). As the name suggests, the UOP includes an orbiter that collects data about the icy planet and its moons, as well as probes that will descend directly into the planet’s atmosphere to obtain information.
The new study was published in Geophysical Research in December 2022.
Lee Kwang-sik, science columnist [email protected]