Chapter 28: Stars and Galaxies
Section 1: A Closer Look at Light
1. What is electromagnetic radiation? ___________________________________________________________
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a. What are the 7 kinds of electromagnetic radiation?
i. ____________________(characteristic)_____________________________________________
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ii. ____________________(characteristic)_____________________________________________
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iii. ____________________(characteristic)_____________________________________________
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iv. ____________________(characteristic)_____________________________________________
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v. ____________________(characteristic)_____________________________________________
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vi. ____________________(characteristic)_____________________________________________
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vii. ____________________(characteristic)_____________________________________________
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b. How do all of these forms of electromagnetic radiation travel? ________________________________
i. How do you determine the length of these waves? ____________________________________
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c. What form of electromagnetic radiation does a spectroscope use? _______________________________
i. What is a continuous spectrum? ____________________________________________________
1. What emits this type of spectra? _____________________________________________
ii. What is an absorption spectrum? __________________________________________________
1. What emits this type of spectra? _____________________________________________
iii. What is n emission spectrum? _____________________________________________________
1. What emits this type of spectra? _____________________________________________
d. Explain how the Doppler effect can tell astronomers whether a star is moving toward or moving away
from Earth ____________________________________________________________________________
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e. How does spectral analysis tell astronomers what elements are found in a star? ____________________
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Section 2: Stars and their Characteristics:
The grouping of stars as seen from the night sky on Earth are called constellations
1. Explain why these are not “natural groupings” ______________________________________________________
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2. Explain how constellations appear to move across the sky over the course of a day and a year
a. Day: _______________________________________________________________________________
b. Year: _______________________________________________________________________________
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3. What is apparent magnitude? _________________________________________________________________
a. Explain the numeric system used to describe the brightness of star as seen from Earth _____________
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i. Example of bright star and apparent magnitude: _______________________________________
ii. Example of a dim star and its apparent magnitude: _____________________________________
4. What is absolute magnitude? __________________________________________________________________
a. What does this have to do with luminosity? _________________________________________________
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b. What does this end up being a comparison of? _______________________________________________
5. What is an astronomical unit? __________________________________________________________________
a. Where is this unit used in determining distances in space? _____________________________________
6. What is a light year? __________________________________________________________________________
a. How far is that? ________________________________________________________________________
7. What is a parsec? _____________________________________________________________________________
a. How far is that? ________________________________________________________________________
8. Explain how parsecs and parallax are related _______________________________________________________
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9. Explain the difference between mass and size in stars ________________________________________________
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10. What about stellar density? ____________________________________________________________________
11. Stars also vary in temperature, which will affect their color. What are the colors associated with temperature
from hottest to coolest?
a. _________________________________________
b. _________________________________________
c. _________________________________________
d. _________________________________________
e. _________________________________________
f. _________________________________________
12. What is a Cepheid variable star and how is it different from a “regular” star? _____________________________
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a. How do astronomers use Cepheid variable stars to determine distance to other galaxies? ____________
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13. What is an eclipsing binary star? Is it only one star? _________________________________________________
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Section 3: Life Cycles of Stars
1. What are the 4 main categories of stars on the Hertzsprung-Russell Diagram?
a. _______________________________________________________
b. _______________________________________________________
c. _______________________________________________________
d. _______________________________________________________
2. In the diagram below, list the phases of the stars’ life
Section 4: Galaxies and the Universe
1. What is a galaxy? _____________________________________________________________________________
2. How many galaxies are in our universe? ___________________________________________________________
3. There are 3 typical types of galaxies list them below with a few characteristics for each type
a. __________________( characteristics) _____________________________________________________
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b. __________________(characteristics) _____________________________________________________
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c. __________________(characteristics) _____________________________________________________
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4. What are active galaxies and quasars? ____________________________________________________________
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5. What is the Big Bang Theory? ___________________________________________________________________
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