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Ask an Astronomer

Ask an Astronomer

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NASA scientists answer questions about astronomy and objects in space. The topics they discuss are varied and touch on different aspects of space science and exploration.

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.
Ask an Astronomer
Episode 1
2 minutes 34 seconds
Grade Level: 7 - 12
The celestial image of a red starry surface. Caption: Where new stars are born,
Ask an Astronomer
Episode 2
2 minutes 8 seconds
Grade Level: 7 - 12
Sun and a red planet in outer space. Caption: we can tell what comprises the atmospheres.
Ask an Astronomer
Episode 3
3 minutes 4 seconds
Grade Level: 7 - 12
An image of the outer space. Caption: it's eventually blocks out all visible light.
Ask an Astronomer
Episode 4
2 minutes 30 seconds
Grade Level: 7 - 12
A huge mass of hot gas swirls into a star. Caption: that swirls onto the massive star.
Ask an Astronomer
Episode 5
3 minutes 29 seconds
Grade Level: 7 - 12
A galaxy fades out. Caption: The original galaxy would be gone.
Ask an Astronomer
Episode 6
2 minutes 7 seconds
Grade Level: 7 - 12
An electromagnetic spectrum with a bright star over the infrared range. Caption: Hotter objects glow in visible light.
Ask an Astronomer
Episode 7
3 minutes 16 seconds
Grade Level: 7 - 12
ASL
illustration of asteroids revolving the sun and other planets. Caption: Asteroids, though, move across the sky at different rates.
Ask an Astronomer
Episode 8
2 minutes 4 seconds
Grade Level: 7 - 12
Illustration of a wave striking an atom. Caption: The shortest wavelength light are gamma rays,
Ask an Astronomer
Episode 9
6 minutes 58 seconds
Grade Level: 7 - 12
Illustration of a woman talking to the Alien M51. Caption: You've got to move the earth back where it belongs.
Ask an Astronomer
Episode 10
4 minutes 26 seconds
Grade Level: 7 - 12
Animation of two galaxies colliding. Caption: they smash together with tremendous force.
Ask an Astronomer
Episode 11
1 minutes 54 seconds
Grade Level: 7 - 12
Image of Andromeda galaxy. Caption: is about 160,000 light years away.
Ask an Astronomer
Episode 12
2 minutes 33 seconds
Grade Level: 7 - 12
Illustration of the earth revolving the sun. Caption: As the earth moved around the sun,
Ask an Astronomer
Episode 13
2 minutes 52 seconds
Grade Level: 7 - 12
An illustration depicts the spiral structure of a galaxy. Caption: Many galaxies have a spiral structure,
Ask an Astronomer
Episode 14
1 minutes 54 seconds
Grade Level: 7 - 12
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