When NASA’s Voyager 2 spacecraft flew by Uranus in 1986, it offered scientists’ first shut peep of this ice-giant planet. Alongside the discovery of fresh moons and rings, baffling fresh mysteries confronted the scientists: the energized particles around Uranus defied their conception of how magnetic fields work to trap particle radiation. In step with a fresh sight, the provision of that particular person mystery is a cosmic accident: it looks to be that in the times good sooner than Voyager 2’s flyby, Uranus had been plagued by an peculiar more or less attach climate that squashed the planet’s magnetic subject, dramatically compressing its magnetosphere.
The principle panel of this artist’s theory depicts how Uranus’ magnetosphere used to be behaving sooner than the flyby of NASA’s Voyager 2; the 2d panel shows an peculiar more or less photo voltaic climate used to be occurring all over the 1986 flyby, giving scientists a skewed take into legend of the magnetosphere. Image credit: NASA / JPL-Caltech.
Planetary magnetospheres — the station around a planet dominated by its magnetic subject — impact the atmosphere around a planet, and conception their properties is needed for mission planning.
Voyager 2’s flyby of Uranus revealed a utterly different magnetosphere that used to be strongly uneven, perceived to lack plasma — a customary ingredient of different planets’ magnetospheres — and had unusually intense belts of extremely full of life electrons.
The traits from this single dimension earn since been outdated as the root of conception Uranus’ magnetic subject, however these anomalies were complex to existing with out complex physics.
“If Voyager 2 had arrived good just a few days earlier, it could per chance probably probably well earn seen a fully utterly different magnetosphere at Uranus,” acknowledged Dr. Jamie Jasinski, a researcher at NASA’s Jet Propulsion Laboratory.
“The spacecraft saw Uranus in prerequisites that simplest happen about 4% of the time.”
Dr. Jasinski and colleagues reanalyzed the Voyager 2 recordsdata sooner than the flyby and found that the probe met Uranus good after an intense photo voltaic wind match, all by which a stream of charged particles used to be launched from the Solar’s atmosphere.
This compressed the Uranian magnetosphere, leaving it in a snort that simplest happens 4% of the time.
This snort would stare a magnetosphere empty of plasma with extremely enraged electron radiation belts.
The authors counsel that owing to the variation of the photo voltaic wind at Uranus, there could well even be two magnetospheric cycles all over the photo voltaic minimal.
Moreover, there could well even be a in point of fact low likelihood that Titania and Oberon — the outermost main Uranian moons — orbit originate air the magnetosphere, that could well also enable scientists to detect subsurface oceans with out interference from the magnetosphere.
“The 1986 flyby used to be crammed with surprises, and we were procuring for an explanation of its peculiar habits,” acknowledged Dr. Linda Spilker, also from NASA’s Jet Propulsion Laboratory.
“The magnetosphere Voyager 2 measured used to be simplest a snapshot in time.”
“This fresh work explains just a few of the obvious contradictions, and this is able to alternate our take into legend of Uranus over all all over again.”
The findings were published as of late in the journal Nature Astronomy.
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J.M. Jasinski et al. The anomalous snort of Uranus’s magnetosphere all over the Voyager 2 flyby. Nat Astron, published on-line November 11, 2024; doi: 10.1038/s41550-024-02389-3
