The Expanding Universe
Students follow the evidence for an expanding universe and a hot Big Bang: redshifted galaxy light, the Hubble Lemaitre law, the mix of light elements and the cosmic microwave background.
Grades 5-8About 15 minutes of narrated flight, plus discussion stops7 stops
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What students will see and do
Students fly from Earth to Andromeda, the Virgo Cluster, the cosmic web and out to the observable universe while Aetherion explains the Doppler effect, galaxy redshifts and the oldest light in the sky. The lesson pauses for discussion at Earth, the Virgo Cluster and the cosmic web.
Learning objectives
- Explain the Doppler effect for sound and apply it to redshift and blueshift of light.
- Describe the Hubble Lemaitre law and use the raisin bread model to show that expansion has no center.
- Identify the three main pieces of evidence for the Big Bang: galaxy redshifts, the hydrogen and helium mix, and the cosmic microwave background.
- Distinguish what the Big Bang theory explains from open questions science has not yet answered.
NGSS connections
| MS-ESS1-2 | Students use models of gravity and expansion to explain why nearby galaxies like Andromeda can approach while distant galaxies recede. |
|---|---|
| MS-PS4-1 | Students describe how stretching and squeezing a wave changes its wavelength, connecting sound pitch to the color shift of light. |
| MS-ESS1-3 | Students analyze distance and speed data for galaxies and the scale of the observable universe. |
Stops on this journey
- The Sound of a Passing Siren (discussion stop)
- The First Galaxy Speeds
- Farther Means Faster (discussion stop)
- Running the Movie Backward (discussion stop)
- The Hot Beginning
- The Oldest Light
- What We Still Do Not Know
Vocabulary
- Doppler effect
- redshift
- blueshift
- spectrum
- expansion
- Big Bang
- cosmic microwave background
- evidence