: Stars form within cold, dense clouds of gas and dust known as molecular clouds or stellar nurseries. Gravity causes these clouds to collapse into hot, spinning "protostars".
Astronomers categorize stars based on their spectral characteristics , which correspond to their surface temperatures. Star Basics - NASA Science : Stars form within cold, dense clouds of
Every star undergoes a distinct life cycle that can last from a few million to trillions of years, depending on its initial mass. : Stars form within cold
: Once the core temperature reaches a critical point, nuclear fusion begins, and the star enters its most stable phase, fusing hydrogen into helium. nuclear fusion begins
: Stars form within cold, dense clouds of gas and dust known as molecular clouds or stellar nurseries. Gravity causes these clouds to collapse into hot, spinning "protostars".
Astronomers categorize stars based on their spectral characteristics , which correspond to their surface temperatures. Star Basics - NASA Science
Every star undergoes a distinct life cycle that can last from a few million to trillions of years, depending on its initial mass.
: Once the core temperature reaches a critical point, nuclear fusion begins, and the star enters its most stable phase, fusing hydrogen into helium.