WEBVTT FILE

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Have you ever wondered how

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even though the Sun is so much

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bigger than the Moon

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they appear to be the same size in the sky?

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Or how the Moon can cover up

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the Sun and cause a total solar eclipse?

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Let's try something out.

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Take any two

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differently sized circles.

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I'm using a paper plate

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and a coin I found.

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Secure the larger circle

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either by having a friend hold onto it for you

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or by using a little bit of tape.

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Now what you're going to want to do

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is take the smaller circle

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and hold it at arm's length

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and close one eye.

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See if it overlaps the larger circle.

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If it doesn't,

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take a few more steps back and try again

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until the smaller circle

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completely overlaps the larger circle.

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What we found here is the spot

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where the smaller object appears to look

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the same size as the bigger object

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despite being completely different sizes

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Even though the Moon is about 400 times smaller than the Sun,

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it's also 400 times closer to us.

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So when both the Sun and the Moon appear in our sky

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the Moon can completely cover up the Sun

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and cause a total solar eclipse!

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Try this at home

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and see if you can find the point where

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objects appear to be the same size

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despite being completely different.

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Eclipses are all about perspective and distances.

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The distance and angle of the moon

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can vary throughout the year

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so sometimes instead of a total solar eclipse,

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we can get a partial solar eclipse

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when the moon only covers part of the Sun

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or an annular solar eclipse

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when the Sun peeks out around the Moon

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so that it looks like a big  ring of fire.

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Thanks for watching, and we'll see you next time.