There may be hidden oceans lurking around Uranus.
New evidence suggests that one or two of the giant’s 27 moons may have liquid oceans beneath the rocks and ice. What makes the space around Uranus so liquid are Miranda and Ariel, one or both of which may be blasted by ocean currents.
The information, which came from the Voyager 2 mission that flew past Earth on its way to space almost 40 years ago – the only spacecraft to do so – makes it the best decision to send another probe to Uranus.
“We’ve been making the case for several years now that solar energy and solar energy are important not only for understanding the universe but also for contributing to major planetary science research,” says astronomer Ian Cohen of Johns Hopkins Applied Physics. Laboratory.
“It seems that can be the case for data that is older than me. It just goes to show how valuable it can be to go to the system and check it first.”
Cohen and his team presented their findings on March 16 at the 54th Congress of Lunar and Planetary Science, and a paper describing them has been accepted for publication. Geophysical Research Letters.
During Voyager 2’s flyby of Uranus in 1986, its Low-Energy Charged Particle instrument picked up something unusual: small particles that appeared to be trapped in parts of Uranus’ magnetosphere. They should spread out, but they stay at the equator, near the directions of Miranda and Ariel.
At that time, scientists believed that the strange history was showing the injection of energetic electrons from a source such as a substorm in the magnetosphere of Uranus. But upon closer inspection, Cohen and his colleagues found that the electrons did not show the pattern expected from the injection of the storm.
This opened up a huge can of worms, because now scientists were back at square one, trying to understand where the electrons came from. The most interesting thing, they said, was the pitch of electrons: part of their velocity and magnetic field.
To maintain the angle seen by Voyager 2, a stable electron source would be needed, crucial to overcome possible scattering and loss due to plasma currents in the planet’s magnetosphere.
Without this type of source, in the right place and with precision, the team determined through imaging, the circular distribution of electrons becomes uniform within a few hours.
By digging deeper into the Voyager 2 data, the team looked for such a source. Their observations showed clearly and indisputably the distance between Miranda and Ariel, suggesting a source of strong ions in this area.
As for what would make those ions… well, 37 years since Voyager 2 visited Uranus, scientists have made some progress on the matter. Voyager 2 made a similar discovery in the atmosphere around Saturn, which was discovered many years later in Cassini data to be made up of water ice on what we now know to be the ocean’s moon, Enceladus. And another similar discovery led us to Jupiter’s ocean moon Europa.
“It’s not uncommon for particle energy measurements to be a precursor to finding an ocean world,” says Cohen.
As for which moon — Miranda, the smallest of Uranus’ five main moons, or Ariel, the brightest — it’s kind of 50-50 at the moment. It could be either. Or all of them. Both moons are showing signs of a recent natural resurgence, which may be accompanied by liquid material erupting internally.
But, so far, we have only one data. Planetary scientists have been clamoring for Uranus, perhaps Neptune included. This world has so many amazing things that learning more about them can be fun and rewarding.
The possibility of a messy moon is just icing on the cake.
“These observations are consistent with the exciting possibility of having an oceanic moon there,” says Cohen. “We can always make more samples, but until we have new data, the conclusion will be limited.”
This research was presented at the 54th Lunar and Planetary Science Conference, and has been accepted for publication Geophysical Research Letters.