C894 GEOS 2104
Astronomy
FA REVIEW
©WGU 2024/2025
,1. Multiple Choice: What is the primary factor that determines the
color of a star?
a) Distance from Earth
b) Size
c) Temperature
d) Age
Correct Answer: c) Temperature
Rationale: The color of a star is determined by its surface
temperature, with hotter stars appearing blue or white and cooler
stars appearing red or orange.
2. Fill-in-the-Blank: The spectral class of a star is determined by its
__________.
Correct Answer: Temperature
Rationale: The spectral class of a star is an indication of its
temperature, with classes ranging from O (hottest) to M (coolest).
3. True/False: A supernova is the explosion of a dwarf star.
Correct Answer: False
Rationale: A supernova is the explosion of a massive star, not a
dwarf star.
©WGU 2024/2025
, 4. Multiple Response: Which of the following are effects of the
Moon on Earth? (Select all that apply)
a) Tides
b) Eclipses
c) Seasons
d) Ocean currents
Correct Answers: a) Tides, b) Eclipses
Rationale: The Moon's gravitational pull causes tides, and it can
cause eclipses when it passes between the Earth and the Sun or
when Earth passes between the Sun and the Moon.
5. Multiple Choice: What phenomenon causes a star to appear to
twinkle?
a) Changes in the star's brightness
b) Earth's rotation
c) Atmospheric turbulence
d) Variations in star size
Correct Answer: c) Atmospheric turbulence
Rationale: The twinkling of stars, or stellar scintillation, is caused
by the passing of starlight through different layers of Earth's
turbulent atmosphere.
©WGU 2024/2025
Astronomy
FA REVIEW
©WGU 2024/2025
,1. Multiple Choice: What is the primary factor that determines the
color of a star?
a) Distance from Earth
b) Size
c) Temperature
d) Age
Correct Answer: c) Temperature
Rationale: The color of a star is determined by its surface
temperature, with hotter stars appearing blue or white and cooler
stars appearing red or orange.
2. Fill-in-the-Blank: The spectral class of a star is determined by its
__________.
Correct Answer: Temperature
Rationale: The spectral class of a star is an indication of its
temperature, with classes ranging from O (hottest) to M (coolest).
3. True/False: A supernova is the explosion of a dwarf star.
Correct Answer: False
Rationale: A supernova is the explosion of a massive star, not a
dwarf star.
©WGU 2024/2025
, 4. Multiple Response: Which of the following are effects of the
Moon on Earth? (Select all that apply)
a) Tides
b) Eclipses
c) Seasons
d) Ocean currents
Correct Answers: a) Tides, b) Eclipses
Rationale: The Moon's gravitational pull causes tides, and it can
cause eclipses when it passes between the Earth and the Sun or
when Earth passes between the Sun and the Moon.
5. Multiple Choice: What phenomenon causes a star to appear to
twinkle?
a) Changes in the star's brightness
b) Earth's rotation
c) Atmospheric turbulence
d) Variations in star size
Correct Answer: c) Atmospheric turbulence
Rationale: The twinkling of stars, or stellar scintillation, is caused
by the passing of starlight through different layers of Earth's
turbulent atmosphere.
©WGU 2024/2025
