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Next US Total Solar Eclipse (Apr 8, 2024)

Learn about eclipses

moon lined up between the sun and earth, blocking the sun and casting a shadow on the earth

Discover the science of eclipses.

What is the difference between a total, annular, partial and lunar eclipse?

What are the different types of eclipses?

From Earth we can see two types of eclipses: solar eclipses and lunar eclipses. These occur when the Sun, Earth, and moon align in a straight or almost straight configuration. Astronomers call this syzygy!

Why Don't We Have an Eclipse Every Month?

Why don't we have an eclipse every month?

A 3-D model of the Earth, the moon, and the Sun helps us understand the celestial mechanics of total solar eclipses—and shows us why they happen when they do.

How to Predict Eclipses
How to Predict Eclipses
How do we know when an eclipse is going to happen? Find out how eclipses can be predicted, and learn about Saros cycles, or families of repeating eclipses.
How can the moon cover the sun during a solar eclipse?
How Can the Moon Cover the Sun?
The moon is 400 times smaller than the Sun, but it's also about 400 times closer to Earth.
Understanding Eclipses, the Earth-Sun-Moon Scale Model
Earth-Sun-Moon Scale Model
See the true scale of the solar system to understand what makes total solar eclipses so rare.
The Last Eclipse

Will there always be total solar eclipses?

Experience this phenomenon from Earth while you still can! In a little more than half a billion years, you will have missed your chance.

two people comparing a scale models of the earth and moon

Eclipse Activities 

Explore hands-on, teacher-tested activities for the classroom and beyond.

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