Did a supernova kill dinosaurs

Answer 1

At the moment, no substantial evidence has been gathered to support the claim that a nearby supernova killed the dinosaurs. Scientists are still trying to determine the best method of finding evidence of this, including looking for signs of past gamma ray radiation on the planet's geology and polar ice caps. Consensus among astronomers is that Gamma Rays from a neighborhood supernova (within a few thousand light years) would induce a chemical reaction in the upper atmosphere converting molecular nitrogen into nitrogen oxides, depleting the ozone layer enough to expose the surface to harmful solar and cosmic radiation. This has been proposed as the cause of the Ordovician-Silurian extinction, which resulted in the death of nearly 60% of oceanic life on Earth.

Answer 2

No, a supernova did not directly kill the dinosaurs. The most widely accepted theory is that dinosaurs were wiped out by an asteroid impact that caused massive climate disturbances, including a nuclear winter-like effect, which led to their extinction. Supernovae are extremely powerful explosions of dying stars that release immense amounts of energy, but there is no evidence linking a supernova event to the extinction of the dinosaurs.