Science Standards:
Nature of Science, Patterns of Change, Scientific Models (Scale &
Conceptual)
Objectives:
Materials:
Directions:
1. Partially inflate the balloon to a 10 cm diameter.
2. Cement four cotton balls around the balloon to represent galaxies.
3. Mark one as our home galaxy (the Milky Way).
4. Measure and record the distance from home to each galaxy.
5. Fully inflate the balloon without bursting it.
6. Measure and record each distance again.
7. Complete the student answer sheet questions.
Description: You will model an expanding universe.
Materials:
Introduction:
The spectra of all galaxies exhibit a red shift . What does
this imply about where our galaxy, the Milky Way, is located in the universe?
Procedure:
1. Slightly inflate your balloon to a diameter of approximately 10 cm.
2. Using several small bunches of cotton, attach four cotton balls all around the balloon with rubber cement.
3. Choose one galaxy to represent our own and mark it with a pen. Then
measure the distance to from our galaxy to three of the other galaxies.
distance to galaxy 1: ___________________ cm
distance to galaxy 2: ___________________ cm
distance to galaxy 3: ___________________ cm
4. Slowly inflate the balloon. DO NOT ALLOW IT TO BURST!
5. Again measure the distance from the Milky Way to the previously chosen galaxies.
new distance to galaxy 1: ___________________ cm
new distance to galaxy 2: ___________________ cm
new distance to galaxy 3: ___________________ cm
6. Are all galaxies moving away from us at an equal rate? Which ones
are moving away fastest?
7. Accurately measuring the distances between the galaxies is obviously
difficult. It is for astronomers too. How might this difficulty affect
our understanding of the universe?
8. How could you determine the velocity at which a galaxy is moving
away?
8. Discuss what will happen if the universe expands forever. What if
it does not expand forever?
9. Describe what you think the theory of the oscillating universe
might be?
10. Why might astronomers care to determine the rate at which the universe
is expanding?