If you’ve never seen a lunar eclipse, which happens when the moon sneaks into the Earth’s shadow, or a solar eclipse, when that pesky moon blocks the sun for one mind-blowing moment, you definitely need to find out when the next one is, and mark your calendar. These amazing events don’t happen every month, and they’re worth every effort you can make to check them out.
Watch this animation to find out more about eclipses. Then answer the questions in the Take Notes box below.
Need help? You might want to check the definitions of specific vocabulary terms. In addition to the glossary words you’ve already learned, the terms lunar eclipse and solar eclipse will be used. You may pause the animation, rewatch it as many times as you like, and read the transcript.
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The movement and relative position of the Earth, sun, and moon create predictable patterns in the shadows we cast. These are called eclipses.
A lunar eclipse is when the moon is on the far side of the Earth, and we see our own shadow. A solar eclipse is when the moon is between the sun and Earth, and the moon blocks our view of the sun (the moon casts a shadow on us).
So why doesn’t an eclipse happen every month as the moon revolves around Earth? Well, contrary to every animation you’ve probably seen including this one, the moon’s revolution around Earth is tilted.
And eclipses only occur when the moon is aligned with the Earth and shadows have something to fall on. Otherwise, we go along our merry way experiencing full moons and new moons without seeing any eclipses. And when eclipses do happen, whether you see it or not depends on where you happen to be and where the shadow happens to fall.
So with all the variables at play, when you do get to see an eclipse, consider yourself at the right place at the right revolution.