在研究地球闪电之前，Joseph Dwyer 使用在160.9万公里 (a million miles, 1.609 million kilometers) 外运行的 NASA Wind 卫星分析了来自太阳的粒子。在地球上，暴风雨云因其不透明且危险而带来了重大的研究挑战。在近三个世纪（近300年）中，研究人员部署了风筝、气球和火箭来研究它们，然而闪电的启动机制在过去50年里仍然悬而未决。在实验室中，产生火花需要每公尺约300万伏特 (3 million volts per meter, 3 MV/m) 的电场强度以启动电子雪崩。然而，20世纪中叶的测量显示，尽管卫星数据显示全球在任何给定时刻都有超过2,000个活跃的雷暴，但自然雷雨云所拥有的电场通常仅为该临界阈值的十分之一 (a tenth, 10%)，且最多仅为三分之一 (a third, 33.3%)。

为了解决这一差异，科学家最初假设，某些尺寸超过铅笔橡皮擦的冰碎片可以作为导体，将局部电场强度提高10倍或更多 (a factor of 10 or more)。然而，来自太空的观测挑战了这一模型。在1994年，卫星侦测到来自雷雨云的高能伽马射线的意外闪光。这些观测表明，亚原子和高能过程，而非简单的电火花，在闪电启动中起著关键作用。

这引导了对相对论性失控电子雪崩的研究。基于 Aleksandr Gurevich 在1992年的研究工作，该工作显示单个失控电子可以在数百至数千公尺 (hundreds to thousands of meters) 的范围内级联成大约100,000个电子，Joseph Dwyer 提出了一种反馈机制。在此模型中，来自失控电子的伽马射线产生电子-正电子对，使正电子能够在自我放大的循环中触发连续的雪崩，从而迅速增强云层的电场。电脑模拟已证明，这一系列事件放大了雪崩，辐射出伽马射线，并显著提升了电场。

Before studying Earth's lightning, Joseph Dwyer analyzed solar particles using NASA’s Wind satellite orbiting a million miles (1.609 million kilometers) away. On Earth, storm clouds present a significant research challenge because they are opaque and dangerous. Over nearly three centuries, researchers have deployed kites, balloons, and rockets to study them, yet the initiation mechanism of lightning has remained unsolved for the past 50 years. In laboratories, generating a spark requires an electric field strength of approximately 3 million volts per meter (3 MV/m) to initiate an electron avalanche. However, measurements from the mid-20th century revealed that natural thunderclouds possess fields that are typically only a tenth (10%), and at most a third (33.3%), of this critical threshold, despite satellite data showing over 2,000 active thunderstorms globally at any given moment.

To resolve this discrepancy, scientists initially hypothesized that ice shards, some exceeding the size of a pencil eraser, could act as conductors to enhance the local electric field strength by a factor of 10 or more. However, observations from space challenged this model. In 1994, satellites detected unexpected flashes of highly energetic gamma rays emanating from thunderclouds. These observations suggested that subatomic and high-energy processes, rather than simple electric sparks, play a critical role in lightning initiation.

This led to the investigation of relativistic runaway electron avalanches. Building on Aleksandr Gurevich’s 1992 work showing that a single runaway electron could cascade into approximately 100,000 electrons over hundreds to thousands of meters, Joseph Dwyer proposed a feedback mechanism. In this model, gamma rays from runaway electrons produce electron-positron pairs, allowing positrons to trigger successive avalanches in a self-amplifying loop that rapidly intensifies the cloud's electric field. Computer simulations have demonstrated that this chain of events amplifies avalanches, radiates gamma rays, and significantly boosts the electric field.