which stages do all stars have in common in their life cycles? Select all that apply.
White dwarf
Black hole
Nebula
Protostar
White dwarf and black hole
The stages that all stars have in common in their life cycles are:
1. Nebula: Stars start their lives as massive clouds of gas and dust called nebulae. Nebulae are the birthplaces of stars.
2. Protostar: Within a nebula, gravity causes the gas and dust to come together, forming a protostar. The protostar is a contracting and heating phase where the star begins to take shape.
Please note that not all stars go through the next two stages:
3. White dwarf: After a main sequence star exhausts its nuclear fuel, it may evolve into a white dwarf. This occurs for stars with low to medium mass, like our Sun. A white dwarf is a dense, hot remnant that no longer undergoes fusion.
4. Black hole: Stars with very high mass could undergo a supernova explosion at the end of their lives. If the core of the star is massive enough, it can collapse under gravity, forming a black hole. Black holes have extremely strong gravitational forces from which nothing, not even light, can escape.
So, the correct stages that all stars have in common are Nebula and Protostar.
To determine which stages all stars have in common in their life cycles, we need to understand the general sequence of stellar evolution. Here's a breakdown of each stage and whether it applies to the four choices given:
1. Nebula: A nebula is a vast cloud of gas and dust in space. It is the birthplace of stars. So, all stars start their life cycle as a nebula.
2. Protostar: As a gravitational collapse occurs within a nebula, a dense core forms called a protostar. This is the next stage after the nebula and is common to all stars.
3. White dwarf: In the later stages of stellar evolution, low- to medium-mass stars (like our sun) exhaust their nuclear fuel and eventually become a white dwarf. So, not all stars end their lives as white dwarfs.
4. Black hole: The stage of becoming a black hole is exclusive to massive stars. When such a star runs out of nuclear fuel, it undergoes a supernova explosion and can collapse into a black hole due to its extreme mass. Hence, not all stars become black holes.
In summary, the two stages that all stars have in common are Nebula and Protostar.