Mathematical model provides bolt of understanding for lightning-produced X-rays

In the early 2000s, scientists observed lightning discharge producing X-rays comprising high energy photons—the same type used for medical imaging. Researchers could recreate this phenomenon in the lab, but they could not fully explain how and why lightning produced X-rays. Now, two decades later, a Penn State-led team has discovered a new physical mechanism explaining naturally occurring X-rays associated with lightning activity in the Earth's atmosphere.