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Ask an Astronomer: Why Aren't There Any Green Stars?

3 minutes 16 seconds

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Dr. Michelle Thaller explains the relationship between visible light and the principle of black-body radiation. These two aspects along with the anatomy of the human eye explain why stars don't appear green in the night sky. Part of the "Ask an Astronomer" series.

Media Details

Runtime: 3 minutes 16 seconds

Topic: Science
Subtopic: Astronomy, Physics, Space Sciences
Grade/Interest Level: 7 - 12
Standards:

Release Year: 2008
Producer/Distributor: NASA Jet Propulsion Lab
Series: Ask an Astronomer
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Ask an Astronomer Website

An Illustration depicts the three positions of the universe. The difference between the first two and the last two positions is labeled, + 2 units. The difference between the first and last positions is labeled, + 4 units. Caption: the more the expansion pushes them apart.

The celestial image of a red starry surface. Caption: Where new stars are born,

Sun and a red planet in outer space. Caption: we can tell what comprises the atmospheres.

An image of the outer space. Caption: it's eventually blocks out all visible light.

A huge mass of hot gas swirls into a star. Caption: that swirls onto the massive star.

A galaxy fades out. Caption: The original galaxy would be gone.

An electromagnetic spectrum with a bright star over the infrared range. Caption: Hotter objects glow in visible light.

illustration of asteroids revolving the sun and other planets. Caption: Asteroids, though, move across the sky at different rates.

Illustration of a wave striking an atom. Caption: The shortest wavelength light are gamma rays,

Illustration of a woman talking to the Alien M51. Caption: You've got to move the earth back where it belongs.