Question

life cycle of stars color by numbers
directions: answer each question by circling the correct choice. after you have completed all the questions color the picture using the assigned colors.

1. all stars begin as a
2. stars are formed when enormous clouds of gas collapse under their own gravity igniting a reaction
3. what is the most important factor controlling the evolution of a star?
4. during its main sequence lifetime, a star is kept from collapsing under its own weight by
5. what are the two most abundant elements in a main sequence star?
6. what part of the life cycle of stars is our sun in?
7. a star that has ignited and has used up all of the hydrogen at its core it begins to collapse. the increased heat at the core pushes outward and the outer shell begins to expand. at this stage, the star becomes a
8. when a red supergiant can no longer maintain equilibrium, it undergoes a sudden catastrophic collapse resulting in a massive explosion called a
9. are formed when a red giants outer atmosphere drifts away.
10. why wont our sun ever become a black hole?
11. as medium - sized stars age from main sequence to red giants, how do their properties change?
12. a is an object so dense and with so much gravity that even light cannot escape.

Explanation:

1. All stars begin as a nebula. Nebula is a cloud of gas and dust in space where stars are born.
2. Stars are formed when enormous clouds of gas collapse under their own gravity igniting a nuclear fusion reaction. Nuclear fusion is the process where light elements combine to form heavier elements, releasing energy.
3. The most important factor controlling the evolution of a star is mass. A star's mass determines its lifespan, temperature, and the stages it will go through in its life cycle.
4. During its main sequence lifetime, a star is kept from collapsing under its own weight by fusing lighter elements into heavier ones. This nuclear fusion creates an outward pressure that balances the inward pull of gravity.
5. The two most abundant elements in a main sequence star are hydrogen and helium. These are the lightest elements and are the fuel for nuclear fusion in stars.
6. Our Sun is in the main sequence part of the life cycle of stars. This is the stable phase where a star spends most of its life.
7. A star that has ignited and has used up all of the hydrogen at its core begins to collapse. The increased heat at the core pushes outward and the outer shell begins to expand. At this stage, the star becomes a red giant.
8. When a red supergiant can no longer maintain equilibrium, it undergoes a sudden catastrophic collapse resulting in a massive explosion called a supernova.
9. Planetary nebula are formed when a red giant's outer atmosphere drifts away.
10. Our sun won't ever become a black hole because it is too small. Only stars with a very large mass can collapse to form a black hole.
11. As medium - sized stars age from main sequence to red giants, they become larger, less luminous and cooler.
12. A black hole is an object so dense and with so much gravity that even light cannot escape.

Answer:

1. A. nebula (yellow orange)
2. C. nuclear fusion (red orange)
3. C. mass (blue)
4. A. fusing lighter elements into heavier ones. (red)
5. B. hydrogen and helium (sky blue)
6. A. main sequence (yellow green)
7. C. red giant (orange)
8. B. supernova (purple)
9. A. planetary nebula (golden yellow)
10. B. it is too small (magenta)
11. C. They become larger, more luminous and cooler. (light blue)
12. A. black hole (green)