Star Colors and Temperatures
Students learn that a star's color reveals its surface temperature, with blue white stars hottest and red stars coolest, and they practice the spectral types O B A F G K M using real stars they can see by eye.
Grades 5-8About 15 minutes of narrated flight, plus discussion stops8 stops
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What students will see and do
Students fly from Earth to the Orion Nebula's young O stars, then to Rigel, Sirius (with Procyon nearby), the Sun (with Capella mentioned), Arcturus, Betelgeuse and Antares. Aetherion pauses for discussion at the Orion Nebula (why the hottest stars live short lives), the Sun (why it looks white from space but yellow from Earth) and Antares (why the most common stars are invisible to the eye).
Learning objectives
- Explain that hotter glowing objects appear bluer and cooler ones appear redder.
- Identify the spectral types O B A F G K M in order from hottest to coolest, with an example star for several of them.
- Describe why Earth's atmosphere makes the Sun look yellow and the sky look blue.
- Compare a star's color and temperature with its size and total brightness, using Betelgeuse and red dwarfs as examples.
NGSS connections
| MS-PS4-2 | Students describe how glowing objects emit light whose color depends on temperature, and how air scatters light. |
|---|---|
| MS-ESS1-3 | Students compare properties of stars such as temperature, size and brightness to understand scale in the galaxy. |
| MS-PS3-4 | Students connect higher temperature to higher energy emitted, as seen in a heated coil changing color. |
Stops on this journey
- Seeing Color in the Dark
- The Hottest Stars (discussion stop)
- Rigel, Blue White and Brilliant
- Sirius, the White Star
- Your Yellow Sun (discussion stop)
- Arcturus, the Orange Giant
- Betelgeuse, Red and Huge
- Antares and the Red Dwarfs (discussion stop)
Vocabulary
- spectral type
- surface temperature
- blue supergiant
- red supergiant
- giant star
- red dwarf
- scattering
- twinkling