Download Directed Reading A

Name ______________________________ Class___________________Date__________________
Skills Worksheet
Directed Reading A
Section: The Life Cycle of Stars
THE BEGINNING AND END OF STARS
_____ 1. Which of the following statements is NOT true about stars?
a. A star begins its life as a ball of gas and dust.
b. As stars get older, they lose some of their material.
c. Stars last forever.
d. New stars form from the material of old stars.
2. During a star’s life cycle, hydrogen changes to helium in a process called
______________________.
3. When a star dies, either gradually or in a big explosion, much of its material
returns to ______________________.
DIFFERENT TYPES OF STARS
_____ 4. All of the following characteristics are used to classify stars EXCEPT
a. age.
c. brightness.
b. name.
d. temperature.
_____ 5. Which one of the following is NOT true about stars?
a. A star goes through many changes during its life cycle.
b. A star can become a different type of star as it gets older.
c. A star can be classified as more than one type of star during its life
cycle.
d. A star does not change during its life cycle.
Match the correct description with the correct term. Write the letter in the space
provided.
_____ 6. small, hot star in final stage of its life
cycle
_____ 7. star in second and longest stage of its life
cycle
a. red giant star
b. white dwarf star
c. main-sequence star
_____ 8. large, cool star in third stage of its life cycle
Original content Copyright © by Holt, Rinehart and Winston. Additions and changes to the original content are the responsibility of the instructor.
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Stars, Galaxies, and the Universe
Name ______________________________ Class___________________Date__________________
Directed Reading A continued
9. Explain how energy is generated in the core of a star during the second stage
of its life cycle.
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
10. Explain what happens during the third stage of a star’s life cycle as the star
uses up all of its hydrogen.
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
11. Explain the final stage of a star’s life cycle by describing what happens once a
star has lost all of its hydrogen.
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
A TOOL FOR STUDYING STARS
_____ 12. The H-R diagram shows the relationship of a star’s temperature to its
a. brightness.
c. size.
b. color.
d. age.
_____ 13. On what part of the H-R diagram would you find the majority of the
main-sequence stars?
a. top half
c. middle
b. bottom half
d. far corners
14. According to the H-R diagram, the star Canopus has a temperature of about
______________________ and an absolute magnitude of
______________________.
Original content Copyright © by Holt, Rinehart and Winston. Additions and changes to the original content are the responsibility of the instructor.
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Stars, Galaxies, and the Universe
Name ______________________________ Class___________________Date__________________
Directed Reading A continued
Match the correct description with the correct term. Write the letter in the space
provided.
_____ 15. top of modern H-R diagram
_____ 16. bottom of modern H-R diagram
_____ 17. right side of modern H-R diagram
a.
b.
c.
d.
hot (blue) stars
bright stars
cool (red) stars
dim stars
_____ 18. left side of modern H-R diagram
19. Place these stars in order from earliest in life cycle to oldest in life cycle: red
giant, white dwarf, main-sequence star.
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
20. As they age, ______________________ stars move up and to the right on an
H-R diagram.
Match the correct description with the correct term. Write the letter in the space
provided.
_____ 21. stars with low mass, low temperature,
and low absolute magnitude
_____ 22. small hot stars that are dimmer than the
sun
_____ 23. high-temperature stars that quickly use
up their hydrogen
a.
b.
c.
d.
e.
massive blue stars
white dwarf stars
main-sequence stars
red dwarf stars
red giant stars
_____ 24. cool stars with absolute magnitude
_____ 25. stars in the band that runs along the
middle of the H-R diagram
Original content Copyright © by Holt, Rinehart and Winston. Additions and changes to the original content are the responsibility of the instructor.
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Stars, Galaxies, and the Universe
Name ______________________________ Class___________________Date__________________
Directed Reading A continued
WHEN STARS GET OLD
_____ 26. Which one of the following statements is NOT true of supernovas?
a. They are explosions in which a massive star collapses.
b. They are explosions that occur at the beginning of a star’s life.
c. They can be brighter than an entire galaxy for several days.
d. They are explosions in which a star throws its outer layers into
space.
27. A star that has collapsed under gravity is called a(n)
______________________.
28. A rapidly spinning neutron star is called a(n) ______________________.
29. An object so massive that light cannot escape its gravity is a
______________________.
Original content Copyright © by Holt, Rinehart and Winston. Additions and changes to the original content are the responsibility of the instructor.
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Stars, Galaxies, and the Universe