Do planets burst?

It is assumed that in the interior of planets, nuclear energy is liberated not only in natural radioactive decay but also in nuclear chain reactions. A critical layer of fissionable material can form during settling of uranium-dioxide particles in the liquid layer of the core of a planet. Quasi-stationary energy release in the active layer can cause global tectonic phenomena. A shock from impact of a large meteorite on the surface of a planet can lead to rapid and deep transition of the active layer to a supercritical state and then to a burst. Some features of the structure of the solar system are explained by bursts of celestial bodies.