NASA will explore subsurface oceans on three of Uranus's moons.

Authors of a new study have concluded that at least three of Uranus's 28 moons may harbor vast oceans of liquid water beneath their surfaces. Researchers recommend starting the search by examining the icy shells of Miranda, Ariel, and Umbriel. While NASA's new mission to Uranus is still in development, the findings hold significant importance for its future planning and could greatly enhance our understanding of potentially habitable worlds within the Solar System.

2024-11-27 10:00:09https://naked-science.ru/article/astronomy/nasa-zajmetsya-poiskom-po

The five primary moons of the seventh planet from the Sun are often referred to as literary, as their names are derived from characters in the works of William Shakespeare and Alexander Pope. The first two satellites—Titania and Oberon—were discovered by William Herschel in 1787, while the discovery of Miranda was made by Gerard Kuiper in 1948. The next 10 moons were identified by NASA's Voyager 2 spacecraft, and the remaining ones were observed using ground-based and space telescopes.

It is worth noting that the famous spacecraft Voyager 2 passed by Uranus in 1986, during which it sent the first grainy images of the large icy moons back to Earth. Now, nearly 40 years later, specialists from the National Aeronautics and Space Administration (NASA) in the United States are planning to launch another mission to Uranus. Researchers from other universities are also collaborating on this project alongside NASA staff.

The mission is currently in the early planning stages; however, the authors of a new study, presented in the journal Geophysical Research Letters, have already developed a computer model that can be utilized for searching for subsurface oceans using both cameras and other instruments.

To detect subsurface oceans on Miranda, Ariel, and Umbriel, a team led by Doug Hemingway from the Institute for Geophysics at the University of Texas and Francis Nimmo from the University of California (both in the USA) proposed using so-called physical librations—slight oscillations in the moons' rotation. Calculations indicated that if the icy shell of a moon is separated from its core by a liquid ocean, the amplitude of these oscillations would be significantly higher.

For instance, the presence of a subsurface ocean on the moons (if their icy shells are sufficiently thin) could increase the amplitude of oscillations by more than 100 meters. This is due to the ocean allowing the shell to move more freely relative to the core.

In addition to measuring the oscillations in the rotation of Uranus's moons, potential subsurface oceans can also be detected by measuring the gravitational fields of the satellites. Together, both methods can provide additional information about the internal structure of these celestial bodies, as well as determine the thickness of the icy shell, the depth of the ocean, and the characteristics of the rocky core.

The findings of this new study are crucial for planning future space missions: understanding which measurements need to be taken and with what precision will help select appropriate research tools and develop the trajectory for the upcoming flight. It is important to note that the distance between the seventh planet from the Sun and Earth varies regularly (from 2.6 to 3.15 billion kilometers), complicating mission organization and affecting its duration.

Ultimately, the team of scientists concluded that measuring physical librations (with an accuracy of up to 10 meters) using new spacecraft will confirm the existence of subsurface oceans on three of Uranus's moons. The researchers also emphasized that understanding the internal structure of these celestial bodies will shed light on their evolution and geological history.

“The discovery of subsurface oceans with liquid water on Uranus's moons could change our understanding of the conditions necessary for life,” the authors of the scientific paper summarized.