Astronomers have earlier discovered that Uranus has 27 known moons around its orbit. A new study revealed that one/two of these moons of Uranus may have subsurface oceans that pump materials into space. NASA’s Voyager 2 spacecraft which passed the Uranian system around four decades ago discovered some features in radiation data it collected from the moon.
However, the latest studies show that Uranus’ moons Ariel and Miranda could possibly have subsurface oceans. Voyager’s observations decades ago suggest that Uranus’ five largest moons may have subsurface oceans within them. In recent studies, scientists studied radiation and magnetic data obtained by the Voyager 2 spacecraft in 1986 before it flew out of the solar system in December 2018.
The new study revealed that one or two of the icy giant’s 27 known moons of Uranus are pushing out plasma particles into space. Scientists were able to spot this observation as they notice trapped energetic particles the Voyager 2 spacecraft detected as it left the Uranian system. What did scientists learn from this discovery? Continue reading to find out.
What You Should Know about the Moons of Uranus
Scientists explored the data obtained by the Voyager 2 spacecraft in making this fascinating discovery. However, the researchers marvel at the unknown mechanism Miranda and Ariel follow to eject particles into space. But they believe that the reason behind this strange occurrence may be because one or two of the icy moons has a liquid subsurface ocean beneath their frozen surface that is actively pumping plumes of material into space.
Scientists have earlier discovered that some moons around Neptune, Jupiter, and Saturn also release similar particles into space. For example, Jupiter’s moon Europa and Saturn’s moon Enceladus have subsurface oceans beneath them. Scientists relied on the particles and magnetic field data to learn about these subsurface oceans.
“It isn’t uncommon that energetic particle measurements are a forerunner to discovering an ocean world,” study lead author Ian Cohen, a space scientist at the Johns Hopkins Applied Physics Laboratory (APL) in Laurel, Maryland, said in a statement. “We’ve been making this case for a few years now, that energetic particle and electromagnetic field measurements are important not just for understanding the space environment but also for contributing to the grander planetary science investigation,” Cohen added. “Turns out that can even be the case for data that are older than I am. It just goes to show how valuable it can be to go to a system and explore it first-hand.”
How Scientists Came up with This Latest Discovery
Ian Cohen, a space scientist at the Johns Hopkins Applied Physics Laboratory led a team of scientists for this study. The team studied the data obtained by the APL-built Low Energy Charged Particle (LECP) instrument on Voyager 2 to come up with this new study. This powerful instrument specifically analyzes the population of trapped particles. The team of scientists was amazed by the data collected by the LECP instrument.
“What was interesting was that these particles were so extremely confined near Uranus’ magnetic equator,” Cohen said.
The lead author of this study said that the occurrence is strange as magnetic waves found within the system would normally make the particles spread out. However, the researchers noticed that the particles cramped together near Uranus’ equator between Ariel and Miranda. The scientists never assumed that the cramped particles spotted by Voyager 2 spacecraft were due to the possibility of the space probe flying through a plasma stream from the tail of Uranus’ magnetosphere.
The team of researchers studied physical models using the knowledge they obtained about the sub-surface oceans of the moons. This model enabled them to understand that cramped particles could have come from a powerful and consistent source of particles.
They also reached other conclusions stating that the trapped particles could have been coming from either one or two of Uranus’ moons, which could be Ariel and/or Miranda. The researchers assume that the particles were pumped out in the form of vapor plumes. These were similar to plumes pumping out from Enceladus.
Other possible causes of the ejection of materials into space from the moons of Uranus
Scientists also came up with another possible erupting mechanism identified as sputtering. Sputtering is a process whereby high-energy particles merge with a surface, which triggers the ejection of other particles into space. However, the team still needs additional data to finalize the actual cause of this eruption.
“Right now, it’s about 50-50 whether it’s just one or the other,” Cohen said, describing the plume and sputtering hypotheses.
When scientists explored more data, they will tell the exact ejection mechanism that works perfectly in the Uranus system.
“The data are consistent with the very exciting potential of there being an active ocean moon there,” Cohen concluded. “We can always do more comprehensive modeling, but until we have new data, the conclusion will always be limited.”
Why this discovery is about to open another door of space exploration to Uranus
While space agencies are planning future space missions to explore the gas giants and their moons, planetary scientists will be greatly interested in missions that will study Uranian and Neptunian Systems. NASA is planning a $1.4 billion flagship mission in its next major planetary mission to explore Uranus for more data.
However, NASA is hoping to launch this mission in the early 2030s. Scientists will still rely on data obtained during the voyager 2 flyby mission to study these systems and make discoveries. This future mission will obtain more data about the Uranian system which the scientists would explore in determining if the particles are ejecting from subsurface oceans on Ariel and/or Miranda.
The results of this new study were presented during the 54th annual Lunar and Planetary Science Conference on March 16. Journal Geophysical Research Letters have already accepted these results for publication.
Scientific studies like this one often open our eyes to improving our knowledge of astronomy. Scientists will still rely on more data to know the cause of the particles erupting from the moons of Uranus. What do you think about this latest scientific discovery?