What planet has the most intense radiation belts?

Jupiter possesses the most intense radiation belts in the solar system, primarily due to its strong magnetic field and rapid rotation. The planet's magnetic field is about 20,000 times stronger than Earth's, which allows it to trap more energetic particles from the solar wind and cosmic rays. This collection of charged particles forms extensive radiation belts around the planet, similar to Earth’s Van Allen belts but significantly more intense.

The radiation environment near Jupiter is hazardous, with radiation levels energetic enough to damage spacecraft electronics and pose risks to potential human explorers. This reality is a significant consideration for missions targeting Jupiter, influencing protective measures that must be designed for any spacecraft intended to study the planet or its moons.

In contrast, other planets in the options provided have much weaker radiation environments. For instance, Saturn does have radiation belts but they are less intense than those surrounding Jupiter. Mars has a thin atmosphere and minimal magnetic field, resulting in a significantly less intense radiation environment. Uranus, while it has a magnetic field, produces a weaker radiation belt than both Jupiter and Saturn. Thus, Jupiter's unique combination of a strong magnetic field and its ability to capture and retain solar and cosmic energetic particles leads to it having the most intense radiation belts among the planets listed.