Clouds That Block the Light

Students learn that dark nebulae are cold clouds of gas and dust that block starlight, how E. E. Barnard's photographs revealed them, how infrared light lets telescopes see through the dust, and why these dark clouds are where new stars, including the Sun, are born.

Grades 5-8About 15 minutes of narrated flight, plus discussion stops8 stops

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What students will see and do

Students view the Milky Way's Dark Rift, return to Earth, then fly to the Horsehead Nebula, the Orion Nebula, the Coalsack, the Eagle Nebula, the James Webb Space Telescope, and the Sun. Aetherion pauses three times: at Earth (how Barnard's childhood photography skills helped astronomy), at the Coalsack (why cultures see different pictures in the same sky), and at the Eagle Nebula (whether the visible or infrared view of the Pillars is the 'true' one).

Learning objectives

• Explain why dark nebulae appear black against the Milky Way and what they are made of.
• Describe how Barnard's long-exposure photographs showed that many dark patches are clouds, not empty holes.
• Compare what visible light and infrared light reveal inside dusty clouds.
• Explain why cold, dense clouds are good places for stars to form.

NGSS connections

Stops on this journey

1. The Dark Rift
2. Barnard's Photographs (discussion stop)
3. The Horsehead
4. Light on the Edge of Darkness
5. The Coalsack (discussion stop)
6. Pillars of Dust (discussion stop)
7. Seeing Through the Dust
8. Born in the Dark

Vocabulary

• dark nebula
• dust grain
• infrared
• Dark Rift
• star formation
• molecular cloud
• silhouette