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Look up at the night sky. If it is clear, you’ll see stars. You might see just one or two. Or you might see stars filling the sky. Let’s learn about them.
Twinkle, Twinkle
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Stars are bright balls of hot gas. They burn many millions of miles away from Earth. Did you know that the sun is a star?
Colorful Clouds
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A nebula is a cloud of dust and gases. Some nebulas are exploded
explode
AHOLALIKA—GETTY IMAGES
to suddenly break apart in a violent way
(verb)
The soda bottle exploded when I opened it.
stars. Some are stars that are still forming.
Shining Stars
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Stars have different temperatures
temperature
CAVAN IMAGES—GETTY IMAGES
a measurement that shows how hot or cold something is
(noun)
The soup is served at a hot temperature.
. This makes them different colors. Blue stars are the hottest. Red stars are cooler.
So Many Stars
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Our planet is in the Milky Way galaxy. A galaxy can be made up of billions of stars. There are billions of galaxies in the universe
universe
JOHN DAVIS/STOCKTREK IMAGES—GETTY IMAGES
all of space and everything in it, including stars, planets, and galaxies
(noun)
Some scientists study the mysteries of the universe.
. Imagine how many stars there must be. There are too many to count!
Did You Know?
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This is an observatory. It houses a telescope. A telescope makes faraway objects look closer. Astronomers use it to see objects in space.