Uranus' Weak Radiation Belts Possibly Linked to Tilted, Lopsided Magnetic Field Causing 'Traffic Jams'

Uranus has surprisingly weak radiation belts, and researchers may have finally found the answer to this bizarre trait.

Uranus' Weak Radiation Belts Due to Magnetic Field's Position

Researchers may have answered a long-standing enigma about the ice giant Uranus and its feeble radiation belts. The planet's tilted and lopsided magnetic field may be the reason for the belts' fragility. Particles blowing around the planet may experience "traffic jams" due to its magnetic field's position.

The mystery began during Voyager 2's January 1986 visit to Uranus, well before the spacecraft's 2018 departure from the solar system. The spacecraft discovered that Uranus has an uneven magnetic field inclined approximately 60° from its spin axis. Furthermore, Voyager 2 found that Uranus' radiation belts of particles trapped by this magnetic field are roughly 100 times weaker than anticipated.

According to a recent analysis based on simulations performed with Voyager 2 data, these two peculiar features of the ice giant may be related. Its magnetic field is unique among all those in the solar system. Most planets, including Earth, Jupiter, and Saturn, have powerful inherent magnetic fields.

Lead author Matthew Acevski described their magnetic field form as a dipole, which is fairly "conventional." The magnetic field formed is identical to what you anticipate from a regular bar magnet. However, it's different in Uranus, where the planet's field is extremely asymmetrical and gets closer to the planet's surface.

According to Acevski, the study demonstrates how Uranus' magnetic imbalance distorts the planet's proton radiation belt topology, particularly close to the area where Voyager 2 passed by.

Acevski's theory suggested that the magnetic imbalance bent the proton radiation belts, creating areas where the belts were compressed closer to the planet. This resulted in more vigorous intensity, whereas weaker intensity was caused by other locations where they were more dispersed.

One possible explanation for Voyager 2's observations is that it passed through an area where the radiation belts were more widely dispersed, which is why weaker-than-expected proton radiation belts were observed.

ALSO READ: James Webb Space Telescope Captures Uranus' Elusive Zeta Ring, Moons in Festive Photo

Uranus' Elusive Ring Spotted

Last year, NASA's James Webb Space Telescope (JWST) captured the planet's elusive Zeta ring. In December, NASA released new shots of the seventh planet, which appeared festive just in time for the holidays.

Not only does the magnificent picture depict the planet, but it also fully displays its outer and inner rings, including the rarely seen Zeta ring. Yes, Uranus has rings like Saturn. In the picture, nine of its 27 moons are also visible.

The five main moons of Uranus-Ariel, Miranda, Oberon, Titania, and Umbriel-are seen in the larger picture. On the other hand, certain smaller and fainter moons, including those embedded in the rings, are visible in the cropped image.

According to NASA, the images clearly show Uranus's seasonal north polar cap and its spectacular storms below and at its southern border. If humans are to send a spacecraft for a closer inspection, they must be able to navigate through debris from Uranus' rings.