The Voyager 2 flybys of Uranus and Neptune revealed the first multipolar planetary magnetic fields and highlighted how much we have yet to learn about ice giant planets. In this review, we summarize observations of Uranus’ and Neptune’s magnetic fields and place them in the context of other planetary dynamos. The ingredients for dynamo action in general, and for the ice giants in particular, are discussed, as are the factors thought to control magnetic field strength and morphology. These ideas are then applied to Uranus and Neptune, where we show that no models are yet able to fully explain their observed magnetic fields. We then propose future directions for missions, modelling, experiments and theory necessary to answer outstanding questions about the dynamos of ice giant planets, both within our solar system and beyond. This article is part of a discussion meeting issue ‘Future exploration of ice giant systems’.

中文翻译：

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冰巨发电机未充分探索的前沿

天王星和海王星的航海者 2 号飞掠揭示了第一个多极行星磁场，并突出了我们对冰巨行星还有多少了解。在这篇综述中，我们总结了对天王星和海王星磁场的观察，并将它们置于其他行星发电机的背景下。讨论了一般发电机作用的成分，特别是冰巨星的成分，以及被认为控制磁场强度和形态的因素。然后将这些想法应用于天王星和海王星，在那里我们表明还没有模型能够完全解释它们观察到的磁场。然后，我们提出了任务、建模、实验和理论的未来方向，以回答有关我们太阳系内外的冰巨行星发电机的悬而未决的问题。