Our Galactic Neighborhood
Students tour the Local Group, learn how Henrietta Leavitt's Cepheid rule let astronomers measure galaxy distances, and explore how gravity is reshaping the neighborhood.
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 the Milky Way to the Magellanic Clouds, Andromeda, Triangulum and out to a view of the whole Local Group, then return to Andromeda to look at its possible future merger with the Milky Way. The lesson pauses for discussion at the Large Magellanic Cloud, Triangulum and the Local Group.
Learning objectives
- Name the three largest galaxies of the Local Group and describe the Milky Way's satellite galaxies.
- Explain how Cepheid variable stars work as standard candles to measure distance.
- Describe how Hubble's 1923 observation of a Cepheid in Andromeda showed that other galaxies exist.
- Use a scale model to compare the sizes and spacing of Local Group galaxies and predict how gravity will change them.
NGSS connections
| MS-ESS1-2 | Students model how gravity holds the Local Group together, tears apart dwarf galaxies and pulls Andromeda and the Milky Way toward each other. |
|---|---|
| MS-ESS1-3 | Students analyze scale properties such as galaxy sizes and distances in light-years and build a scale model of the Local Group. |
Stops on this journey
- A Galaxy With Followers
- The Heavyweight Satellite (discussion stop)
- The Ruler in the Small Cloud
- Andromeda Gets a Distance
- Triangulum, the Third Spiral (discussion stop)
- The Local Group (discussion stop)
- The Coming Encounter
Vocabulary
- Local Group
- satellite galaxy
- dwarf galaxy
- Cepheid variable
- standard candle
- blueshift
- merger
- light-year