衛星與磁層之間的相互作用對於了解外行星的磁層至關重要。其中一個有趣的現象是觀測到在土星的衛星土衛一（Mimas）和土衛三（Tethys）上的輻解作用（Radiolysis effect），其表面溫度分佈呈現類似電玩遊戲「小精靈（Pac-Man）」的圖案。這些圖案是由困在土星幾乎對稱的雙極磁場中的高能電子的碰撞所造成的。因此，我們想探討類似的效應是否也會出現在天王星的冰質衛星上，由於行星本身的磁場是偏移雙極場（Offset-Tilted Dipole Field），造成周圍的衛星圍繞行星時會經過高度不對稱的磁場。這項研究將透過隨時間調整其磁軸的傾斜並檢查對土衛一表面的帶電粒子撞擊的結果分佈來粗估土星磁極反轉的時間尺度。同時，我們也好奇以其對稱的磁場而聞名的土星，是否在長時間內保持穩定的雙極場，還是在過去曾經歷了磁極的反轉？這項研究有助於更好地了解土星和天王星磁場與其衛星之間的動力學，從而揭示外行星系統中更廣泛的行星演化過程。

The interactions between satellites and their planetary magnetospheres are crucial for understanding the magnetospheres of outer planets. One intriguing phenomenon is the radiolysis effects observed on Saturnian icy moons, Mimas and Tethys, characterized by Pac-man like patterns of surface temperature distribution. These patterns result from the bombardment of energetic electrons trapped within Saturn's nearly symmetrical dipole field. This prompts an investigation into whether similar effects may occur on the icy moons of Uranus and Neptune, which possess highly asymmetric and inclined orbits due to their Offset-Dipole Fields. Simultaneously, Saturn, characterized by its symmetric magnetic field, poses an intriguing question: does it maintain a stable dipole field over an extended period, or has it undergone magnetic reversal in the past? This research focuses on constraining the timescale of Saturn's magnetic reversal by modulating the tilt of its magnetic axis over time and examining the resultant distribution of charged particle impacts on Mimas. To address this, we aim to constrain the timescale of Saturn's magnetic reversal by modulating the tilt of its magnetic axis over time and examining the resultant distribution of charged particle impacts on its innermost moon, Mimas. This research contributes to a better understanding of the dynamics between Saturnian and Uranian magnetic fields and their moons, shedding light on the broader planetary evolution processes within the outer planets.

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