‘Uranus traffic jams’ may explain weak radiation belts around the planet

Produced by: Tarun Mishra Designed by: Manoj Kumar

Mystery of Weak Radiation Belts

Scientists have been puzzled by the weak radiation belts around Uranus since Voyager 2’s visit in 1986. New research suggests the planet’s tilted and asymmetric magnetic field may be causing this phenomenon.

Unique Magnetic Field

Voyager 2 discovered that Uranus’ magnetic field is tilted about 60° from its spin axis and is highly asymmetric. This unusual field could be influencing the behavior of particles trapped in the radiation belts.

Simulation Insights

Researchers used simulations based on Voyager 2 data to study the relationship between Uranus’ magnetic field and its radiation belts. The simulations revealed that the magnetic field’s asymmetry warps the structure of the proton radiation belts.

Credit: NASA

Proton Belt Warping

The simulations showed that the magnetic asymmetry creates regions where the proton radiation belts are more compressed and other regions where they are more spread out. This could explain the weaker-than-expected proton radiation belts observed by Voyager 2.

Credit: NASA

Voyager 2’s Path

When Voyager 2 passed through Uranus, it likely traversed a region where the radiation belts were more dispersed, leading to weaker radiation belt intensity readings.

Credit: NASA

Magnetic Field Model

The research team used a quadrupole magnetic field model, rather than a dipole, to better represent Uranus’ lopsided magnetic field. This model revealed variations in particle speed and density around the planet.

Future Missions

A new spacecraft mission to Uranus, potentially launching in 2030, could provide more in-depth and long-term measurements to verify these simulations. This could help uncover new phenomena related to Uranus’ magnetic field.

Ongoing Research

Lead author Matthew Acevski emphasized the need for continued study of Uranus and its magnetic field. The findings highlight the influence of magnetic asymmetry on radiation belts and the importance of future missions for further exploration. The research was published in the journal Geophysical Research Letters in June.