AGB stars

AGB (Asymptotic Giant Branch) stars are evolved, luminous stars that have burned through the hydrogen and helium fuel in their cores. They have expanded and cooled to become large, bright, and reddish, with a dense core surrounded by shells where nuclear reactions still occur. These stars experience significant mass loss, shedding their outer layers into space, which can create beautiful planetary nebulae. AGB stars play a key role in enriching the universe with heavy elements, such as carbon and nitrogen, which are essential for forming new stars, planets, and life.