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Astro Snack

Astro Snack: Galaxies

What is a galaxy, exactly? 
Astro Snack: Video Segments

Produced by the Space Telescope Science Institute’s Office of Public Outreach in collaboration with NASA’s Universe of Learning partners: California Institute of Technology/IPAC, Center for Astrophysics | Harvard & Smithsonian, and NASA Jet Propulsion Laboratory.
Written by Claire Blome
Design by Joseph Olmsted
Editorial and design input from Dr. Christopher T. Britt, Dr. Quyen Hart, Timothy Rhue II
Voiceover by Yesenia Perez, Dr. Quyen Hart
Music (“Snack Time”) by Joseph Depasquale

Astro Snack. Galaxies.
Text, Astro Snack Galaxies.
Like pizzas, galaxies are sprinkled with ingredients.
A cartoon pizza spins to become a galaxy.
Large galaxies have billions and billions of stars that are bound by gravity.
A galaxy full of stars.
Let's take a closer look. Yep, tons of stars! Most stars have planets making their own solar systems. A galaxy also includes plenty of other ingredients, stars and planets, dust, gas. Galaxies are massive. Plus no two galaxies are exactly the same!
Another, different galaxy appears.
An astronaut character floats by.

Explore More

Find out more with these additional resources from NASA’s Universe of Learning

AstroViz: Shedding New Light on the Whirlpool Galaxy
Marvel at a magnificent spiral galaxy seen in three different types of light
AstroPix: Galaxies
Images of galaxies across the universe
Galaxies: The Building Blocks of the Universe
Read up on the full details behind galaxies