Looking Back in Time
Students learn that light has a finite speed, that a light-year is a unit of distance, and that looking at distant objects means seeing them as they were in the past.
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 Moon and Sun out to Alpha Centauri, Sirius, Polaris, Deneb and the Andromeda Galaxy while Aetherion explains how old each object's light is. The class can pause to discuss at the Sun, Polaris and Andromeda stops.
Learning objectives
- State the speed of light in miles per second and explain that it is finite.
- Define a light-year as a unit of distance, not time.
- Calculate how long ago light left an object when given its distance in light-years.
- Explain why looking farther into space means looking further back in time.
NGSS connections
| MS-ESS1-3 | Students analyze distances and scale in the universe using light travel time and the light-year as a unit. |
|---|---|
| MS-PS4-2 | Students describe light as a wave that travels through space at a finite speed and carries information from its source. |
Stops on this journey
- The Fastest Thing There Is
- Eight Minutes Old (discussion stop)
- Measuring in Light-Years
- A Light From Your Childhood
- Light From Centuries Ago (discussion stop)
- A Distant Beacon
- Light Older Than Humanity (discussion stop)
Vocabulary
- speed of light
- light-year
- lookback time
- parallax
- supergiant
- galaxy
- Polaris
- observatory