Which event marks the beginning of a supernova?
A) The sudden collapse of an iron core into a compact ball of neutrons
B) The onset of helium burning after a helium flash
C) The beginning of neon burning in an extremely massive star
D) The sudden initiation of the CNO cycle

Question

Quizplus · Accepted Answer

The sudden collapse of an iron core into a compact ball of neutrons is what marks the beginning of a supernova. This collapse is triggered by the inability of the core to support its own weight through fusion reactions, leading to a runaway gravitational collapse that releases enormous amounts of energy in the form of neutrinos and shock waves. This energy drives the explosive ejection of the outer layers of the star, resulting in a supernova. The other options - helium burning after a helium flash, neon burning in an extremely massive star, and the CNO cycle - are all processes that occur during the later stages of stellar evolution and are not directly related to the onset of a supernova.

Which Event Marks the Beginning of a Supernova