Stars, Galaxies, and the Universe

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Stars, Galaxies, and the Universe

• Preview
• Multiple Choice
• Short Response
• Reading Skills
• Interpreting Graphics

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Multiple Choice

• 1. What accounts for different stars being seen
  in the sky during different seasons of the year?
• A. stellar motion around Polaris
• B. Earths rotation on its axis
• C. Earths revolution around the sun
• D. position north or south of the equator

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Multiple Choice

• 1. What accounts for different stars being seen
  in the sky during different seasons of the year?
• A. stellar motion around Polaris
• B. Earths rotation on its axis
• C. Earths revolution around the sun
• D. position north or south of the equator

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Multiple Choice, continued

• 2. How do stellar spectra provide evidence that
  stars are actually moving?
• F. Dark-line spectra reveal a stars
  composition.
• G. Long-exposure photos show curved trails.
• H. Light separates into different wavelengths.
• I. Doppler shifts occur in the stars spectrum.

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Multiple Choice, continued

• 2. How do stellar spectra provide evidence that
  stars are actually moving?
• F. Dark-line spectra reveal a stars
  composition.
• G. Long-exposure photos show curved trails.
• H. Light separates into different wavelengths.
• I. Doppler shifts occur in the stars spectrum.

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Multiple Choice, continued

• 3. What happens to main-sequence stars like the
  sun when energy from fusion is no longer
  available?
• A. They expand and become supergiants.
• B. They collapse and become white dwarfs.
• C. They switch to fission reactions.
• D. They contract and turn into neutron stars.

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Multiple Choice, continued

• 3. What happens to main-sequence stars like the
  sun when energy from fusion is no longer
  available?
• A. They expand and become supergiants.
• B. They collapse and become white dwarfs.
• C. They switch to fission reactions.
• D. They contract and turn into neutron stars.

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Multiple Choice, continued

• 4. Which type of star is most likely to be found
  on the main sequence?
• F. a white dwarf
• G. a red supergiant
• H. a yellow star
• I. a neutron star

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Multiple Choice, continued

• 4. Which type of star is most likely to be found
  on the main sequence?
• F. a white dwarf
• G. a red supergiant
• H. a yellow star
• I. a neutron star

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Multiple Choice, continued

• 5. Evidence for the big bang theory is provided
  by
• A. cosmic background radiation.
• B. apparent parallax shifts.
• C. differences in stellar luminosity.
• D. star patterns called constellations.

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Multiple Choice, continued

• 5. Evidence for the big bang theory is provided
  by
• A. cosmic background radiation.
• B. apparent parallax shifts.
• C. differences in stellar luminosity.
• D. star patterns called constellations.

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Short Response

• 6. What type of galaxy has no identifiable
  shape?
• irregular galaxy

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Short Response, continued

• What is the collective name for the Milky Way
  galaxy and a cluster of approximately 30 other
  galaxies located nearby?
• the local group

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Short Response, continued

• 8. What is the name for stars that seem to circle
  around Polaris and never dip below the horizon?
• circumpolar stars

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Reading Skills

• Read the passage below. Then, answer questions
  911.
• Geomagnetic Poles
• Today, we know that Copernicus was right the
  stars are very far from Earth. In fact, stars are
  so distant that a new unit of lengththe
  light-yearwas created to measure their distance.
  A light-year is a unit of length equal to the
  distance that light travels through space in 1
  year. Because the speed of light through space is
  about 300,000 km/ s, light travels approximately
  9.46 trillion kilometers in one year.
• Even after astronomers figured out that stars
  were far from Earth, the nature of the universe
  was hard to understand. Some astronomers thought
  that our galaxy, the Milky way, included every
  object in space. In the early 1920s Edwin Hubble
  made one of the most important discoveries in
  astronomy. He discovered that the Andromeda
  galaxy, which is the closest major galaxy to our
  own, was past the edge of the Milky Way. This
  fact confirmed the belief of many astronomers
  that the universe is larger than our galaxy.

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Reading Skills, continued

• 9. Why was Edwin Hubbles discovery important?
• A. Hubbles discovery showed scientists that the
  universe was smaller than previously thought.
• B. Hubble showed that the Andromeda galaxy was
  larger than the Milky Way galaxy.
• C. Hubble's discovery showed scientists that the
  universe was larger than our own galaxy.
• D. Hubble showed that all of the stars exist in
  two galaxies, the Andromeda and the Milky Way.

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Reading Skills, continued

• 9. Why was Edwin Hubbles discovery important?
• A. Hubbles discovery showed scientists that the
  universe was smaller than previously thought.
• B. Hubble showed that the Andromeda galaxy was
  larger than the Milky Way galaxy.
• C. Hubble's discovery showed scientists that the
  universe was larger than our own galaxy.
• D. Hubble showed that all of the stars exist in
  two galaxies, the Andromeda and the Milky Way.

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Reading Skills, continued

• Because the sun and Earth are close together, the
  distance between the sun and Earth is measured in
  light-minutes. A light-minute is the distance
  light travels in 1 minute. The sun is about 8
  light-minutes from Earth. What is the approximate
  distance between the sun and Earth?
• F. 2,400,000 km
• G. 18,000,000 km
• H. 144,000,000 km
• I . 1,000,000,000 km

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Reading Skills, continued

• Because the sun and Earth are close together, the
  distance between the sun and Earth is measured in
  light-minutes. A light-minute is the distance
  light travels in 1 minute. The sun is about 8
  light-minutes from Earth. What is the approximate
  distance between the sun and Earth?
• F. 2,400,000 km
• G. 18,000,000 km
• H. 144,000,000 km
• I . 1,000,000,000 km

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Reading Skills, continued

• 11. Why might scientists use light-years as a
  measurement of distance between stars?
• Light-years can express vast distances in
  compact form. When expressing distance between
  stars, using light-years is easier and more
  efficient than using kilometers.

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Interpreting Graphics

• The diagram below shows a group of stars called
  the Big Dipper moving over a period of 200,000
  years. Use this diagram to answer question 12.

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Interpreting Graphics, continued

• 12. What does this series of drawings
  demonstrate about the individual stars in such a
  star group?
• Your answer should include the following
• The diagrams show that the individual stars move
  at different rates and in different directions
  from one another constellations are arbitrary
  human distinctions the stars within
  constellations move along individual paths, not
  as a group the familiar patterns that stars form
  in the Earths sky change slowly over time as the
  stars that comprise the patterns move relative to
  each other star movement may take thousands of
  years to become apparent.

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Multiple Choice, continued

• The table below shows data about several
  well-known stars. Distance is given in
  light-years. Use this table to answer questions
  13 through 15.

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Multiple Choice, continued

• 13. Which star has the brightest apparent
  magnitude as seen from Earth?
• F. Rigel
• G. Betelgeuse
• H. Mintaka
• I. Sirius

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Multiple Choice, continued

• 13. Which star has the brightest apparent
  magnitude as seen from Earth?
• F. Rigel
• G. Betelgeuse
• H. Mintaka
• I. Sirius

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Multiple Choice, continued

• 14. Which of these stars is the coolest?
• A. Arcturus
• B. Betelgeuse
• C. Mintaka
• D. Vega

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Multiple Choice, continued

• 14. Which of these stars is the coolest?
• A. Arcturus
• B. Betelgeuse
• C. Mintaka
• D. Vega

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Multiple Choice, continued
15. Which star most likely has a temperature that
is similar to the temperature of our sun? Explain
how you are able to determine this
information. Your answer should include the
following The star in the table with the
closest temperature to the sun is most likely
Capella a stars temperature can be determined
by its color. Stars that have similar colors
share a common temperature range Capella is a
yellow star like the sun and thus it is the most
likely to have a temperature similar to that of
the sun