Kugelblitz (astrophysics)
A kugelblitz (German: [ˈkuːɡl̩ˌblɪt͡s] ) (English: ball lightning) is a theoretical astrophysical object predicted by general relativity. It is a concentration of heat, light, or radiation so intense that its energy forms an event horizon and becomes self-trapped.
Source: Wikipedia — Kugelblitz (astrophysics) (CC BY-SA 4.0)