The Universe Life and Death of a Star
The Universe: “Life and Death of a Star” video questions
Astronomy
Name:
Period:
1. There are ________________ stars in our galaxy.
400 billion
2. What are the pillars of creation?
A cloud of dust and hydrogen gas, a “stellar nursery” for the birth of new stars, in the Eagle
Nebular, 700 light years from Earth
3. Each contracting cloud can produce a few dozen to __________________ of stars. A star like our sun requires a gas cloud __________________ times the size of our solar system. The temperature in the middle of a dust disc is initially __________________.
Thousands; hundred; 100s of degrees below zero Fahrenheit
4. After 10 million years, a protostar’s core begins to sustain _____________________________ thermonuclear fusion
5. A star’s biggest opponent is ________________, which wants to crush the star. What holds up the star from gravity, keeping the star in equilibrium? gravity; nuclear fusion, in the form of pressure
6. How hot a star is relates to the ______________ it emits. ___________ stars are hotter and
______________ stars are cooler. color; blue; red
7. What are red dwarfs? Why are they not seen in the night sky?
Red dwarfs are small, common stars with lower surface temperature. They are not seen in the night sky because they are dim stars.
8. __________ is the fundamental thing that drives the life history of stars.
Mass
9. Why do more massive stars live shorter lives that less massive stars?
Higher temperature, higher pressure, higher fusion rate means they consume their “fuel” faster.
10. What will gravity do to the sun when fusion is over?
Gravity will begin to crush the star. Then the core will heat enough to fuse helium together into carbon. The outer atmosphere will evaporate, ejecting gases, causing a planetary nebula.
11. What is a white dwarf?
The remnant of a main sequence star. When the star runs out of “fuel” it contracts until electrons produce enough pressure to balance the force of gravity. Then it cools in the small, dense
Astronomy
Name:
Period:
1. There are ________________ stars in our galaxy.
400 billion
2. What are the pillars of creation?
A cloud of dust and hydrogen gas, a “stellar nursery” for the birth of new stars, in the Eagle
Nebular, 700 light years from Earth
3. Each contracting cloud can produce a few dozen to __________________ of stars. A star like our sun requires a gas cloud __________________ times the size of our solar system. The temperature in the middle of a dust disc is initially __________________.
Thousands; hundred; 100s of degrees below zero Fahrenheit
4. After 10 million years, a protostar’s core begins to sustain _____________________________ thermonuclear fusion
5. A star’s biggest opponent is ________________, which wants to crush the star. What holds up the star from gravity, keeping the star in equilibrium? gravity; nuclear fusion, in the form of pressure
6. How hot a star is relates to the ______________ it emits. ___________ stars are hotter and
______________ stars are cooler. color; blue; red
7. What are red dwarfs? Why are they not seen in the night sky?
Red dwarfs are small, common stars with lower surface temperature. They are not seen in the night sky because they are dim stars.
8. __________ is the fundamental thing that drives the life history of stars.
Mass
9. Why do more massive stars live shorter lives that less massive stars?
Higher temperature, higher pressure, higher fusion rate means they consume their “fuel” faster.
10. What will gravity do to the sun when fusion is over?
Gravity will begin to crush the star. Then the core will heat enough to fuse helium together into carbon. The outer atmosphere will evaporate, ejecting gases, causing a planetary nebula.
11. What is a white dwarf?
The remnant of a main sequence star. When the star runs out of “fuel” it contracts until electrons produce enough pressure to balance the force of gravity. Then it cools in the small, dense