Which stages do all stars have in common in their life cycles?(1 point)
Responses
black hole
black hole
white dwarf
white dwarf
nebula
nebula
protostar
protostar
During their life cycles, all stars go through the following stages:
1. Nebula: Stars begin their life as clouds of gas and dust called nebulae. Gravity causes these nebulae to collapse and form denser regions known as protostars.
2. Protostar: As the cloud of gas and dust collapses, it becomes a protostar. At this stage, the protostar continues to contract and heat up, eventually reaching a temperature and density required for nuclear fusion to begin.
3. Main Sequence: Once nuclear fusion starts, the protostar becomes a main-sequence star. This stage is characterized by a balance between the inward pull of gravity and the outward pressure from nuclear fusion in the star's core. The main-sequence stage is the longest and most stable phase in a star's life.
4. Red Giant: As a main-sequence star exhausts its hydrogen fuel, the core contracts while the outer layers expand, causing the star to enlarge and become a red giant. In this stage, the star fuses helium into heavier elements in its core.
5. Planetary Nebula: In the later stages of a red giant's life, it sheds its outer layers, creating an expanding shell of gas and dust known as a planetary nebula. The remnants of the core form a white dwarf.
6. White Dwarf: A white dwarf is the final stage for low to medium-mass stars like the Sun. It is a hot and dense stellar remnant, composed mostly of carbon and oxygen. White dwarfs gradually cool and fade over billions of years.
It's important to note that while the stages mentioned above are generally applicable to most stars, more massive stars follow a different evolutionary path. These stars can undergo additional stages such as supernovae, neutron star or black hole formation, depending on their mass.