Comets

This passage discusses comets and how they are formed.

Lexile Level: 730L

Categories: Science & Technology


A comet is like a big snowball made from the snow close to the ground. The snowball will not only have ice, but it will have dirt and sticks and other things. Some people call a comet an icy "mudball." The very large piece of ice is made of gas and water. Cosmic dirt floats around this icy center. The center can be more than two miles wide. Comets go around the sun. The closer the comet gets to the sun, the more the loose particles of dust are pushed to the comet's tail. A comet's tail might be as long as 100 million miles. The long tail can be seen from Earth without a telescope. The name comet comes from the Greek word that means "long hair."


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