Our closest star, the Sun, is a middle-aged star. This is good for us, but what exactly does ‘middle-aged star’ mean?
Throughout their lives, stars are in a battle between gravity trying to collapse the star and pressure of the internal nuclear reaction trying to expand the star.
Make a note… It may take time, but gravity always wins!!
Star formation begins with a massive cloud of dust and gasses. The large majority of the cloud is hydrogen.