When “Voyager 2” flew past Uranus almost 40 years ago, it detected something that scientists struggled to comprehend for a long time: a radiation belt surrounded the planet with an incredibly high level of electron emission. Its intensity deviated from all models and made Uranus a true “anomaly” among the Solar System’s giants.
Now, the SwRI team proposes an unexpected solution to this mystery. From their viewpoint, the unusual radiation activity might have arisen not because of Uranus’s properties, but due to a rare solar occurrence—a powerful “space storm” that enveloped the planet’s vicinity at the crucial moment.
The concept emerged when scientists compared Voyager’s data with new insights on how the solar wind affects Earth’s magnetosphere. Conceivably, Uranus, at the time of the probe’s visit, was situated within the zone of the so-called co-rotating interaction region—a structure capable of “pumping up” electrons and accelerating them to high energies.
It is noteworthy that precisely then, “Voyager 2” registered the strongest plasma waves of its mission. Previously, these were considered destroyers of radiation belts, but current observations have proven the opposite: under specific circumstances, such waves become accelerators.
This finding not only clarifies the anomaly but also brings up again the question: how little we comprehend about the ice giants. Scientists are convinced—the time has come to dispatch a full mission to Uranus.
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