Dark Matter and Dark Energy
Students examine the evidence for dark matter (galaxy rotation, cluster motions, gravitational lensing, the cosmic web) and for dark energy (accelerating expansion), and learn how scientists hunt for what they cannot see.
Grades 5-8About 15 minutes of narrated flight, plus discussion stops6 stops
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What students will see and do
Students fly from the Milky Way to Andromeda, the Virgo Cluster and the cosmic web, return to an underground detector on Earth, and finish with the observable universe while Aetherion lays out each clue. The lesson pauses for discussion at Andromeda, the Virgo Cluster and the observable universe.
Learning objectives
- Compare orbital speeds in the solar system with star speeds in a galaxy and explain why flat rotation curves imply unseen mass.
- Describe the contributions of Fritz Zwicky and Vera Rubin to the discovery of dark matter.
- Explain how gravitational lensing lets astronomers weigh a galaxy cluster, including its dark matter.
- State the approximate makeup of the universe (5 percent ordinary matter, 27 percent dark matter, 68 percent dark energy) and describe how dark energy was discovered.
NGSS connections
| MS-ESS1-2 | Students use a model of gravity to explain how unseen mass holds galaxies and clusters together and shaped the cosmic web. |
|---|---|
| MS-PS2-4 | Students construct arguments that gravitational interactions depend on mass, using fast-moving stars and lensing as evidence of extra mass. |
Stops on this journey
- A Galaxy Spinning Too Fast
- Vera Rubin's Discovery (discussion stop)
- Clusters and Bent Light (discussion stop)
- The Invisible Skeleton
- Hunting Dark Matter on Earth
- Dark Energy (discussion stop)
Vocabulary
- dark matter
- dark energy
- rotation curve
- halo
- gravitational lensing
- galaxy cluster
- supernova
- accelerating expansion