Almost Everything We Know About Planet Uranus May Be Wrong

A flyby of Uranus in 1986 is where we gathered much of our knowledge about the distant ice giant, but new research has found that this may not have been a standard representation of the planet’s environment.
The Voyager 2 probe may have passed by Uranus just after an intense solar wind event, which would have created conditions usually only seen around 4 percent of the time, according to a new paper in the journal Nature Astronomy.
This may have led astronomers to believe that Uranus was less similar to the other gas and ice giants in our solar system than it really is.
Launched by NASA in 1977, Voyager 2 flew past Uranus on January 24, 1986, capturing groundbreaking images and data that transformed our understanding of this distant world. Voyager 2 came within about 50,000 miles of Uranus’ cloud tops, providing the first-ever close-up views of the planet, its rings and its moons.
“The Voyager 2 flyby of Uranus in 1986 revealed an unusually oblique and off-centred magnetic field. This single in situ measurement has been the basis of our interpretation of Uranus’s magnetosphere as the canonical extreme magnetosphere of the solar system; with inexplicably intense electron radiation belts and a severely plasma-depleted magnetosphere,” the researchers wrote in the paper.
However, according to the research, Uranus’ magnetosphere appears to have been unusually compressed by solar wind during the precise moments Voyager 2 was flying past, skewing our measurements of the planet’s properties.
What Voyager 2 found was that Uranus’ magnetosphere was bizarrely asymmetrical, with unexpectedly intense electron belts and a surprising lack of plasma. Astronomers were confused, but assumed at the time that this was representative of the planet on a normal day.
After reanalyzing the data from the Voyager 2 flyby, the researchers found that the planet’s magnetosphere was only compressed to the degree it was observed around 4 percent of the time.
“If the spacecraft had arrived only a few days earlier, the upstream solar wind dynamic pressure would have been [about] 20 times lower, resulting in a dramatically different magnetospheric configuration,” the researchers wrote.
They suggest that Uranus and its magnetic environment may be much more like Jupiter, Saturn and Neptune than we first thought.
“We highlight that our understanding of the Uranus system is highly limited, and our analysis shows that any conclusions made from the Voyager 2 flyby are similarly tentative. We suggest that discoveries made by the Voyager 2 flyby should not be assigned any typicality regarding Uranus’s magnetosphere,” the researchers wrote.
Future missions to the ice giant are required to truly understand Uranus’ magnetosphere, the researchers concluded.
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