Question

Giant and supergiant stars are rare because

Answer 1

Giant and supergiant stars are less common because their stages as giants or supergiants are relatively short-lived compared to their long main sequence lifetimes, where stars are stable and burn hydrogen fuel efficiently.

Step-by-step explanation:

Giant and supergiant stars are rare because their enormous size and luminosity imply a very intense and rapid consumption of their nuclear fuel. Despite being thousands of times more luminous than the Sun and having diameters that could extend beyond the orbit of Mars, these stars represent a short-lived phase in the stellar evolutionary process. Stars spend the majority of their lifetimes on the main sequence of the H-R (Hertzsprung-Russell) diagram, where they fuse hydrogen into helium in a stable manner. Once they exhaust the hydrogen in their cores, they evolve off the main sequence and become giants or supergiants. This transition leads to a swift increase in size and luminosity, but these stages are brief compared to their main sequence lifetime, which is why giant and supergiant stars are less common in the observable universe.

Answer 2

Giant and Super Giant Stars are rare because they have a much shorter life than smaller stars