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- Did you know that
the Sun is a star?

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It's actually a star like stars
that you see in the night sky.

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But it's brighter than
those other stars

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because it's closer to us
than any other star.

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Let's go meet Dr. Alex Young
and Dr. Nicki Viall.

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I know that the Sun is
our closest star,

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but just how far away is it?

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- Well, it's pretty far away.

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It's 93 million miles away.

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- And at that distance,
it takes about eight minutes

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for the Sun's light
to reach the Earth.

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- I know that
the Sun rises and sets,

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but where does it go
when I can't see it?

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- Well, the Sun doesn't actually
go anywhere.

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The Sun is always in the center
of the solar system.

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- So, that time it takes
for the Earth to rotate

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is 24 hours,
and that's what we call a day.

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- If Earth's rotation causes
day and night,

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what causes seasons?

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- So, the seasons happen

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because the Earth revolves
around the Sun.

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It travels all the way around
the Sun and comes back.

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- And the other thing
that you're gonna find

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is that,
when you look out at the sky,

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the location of the Sun changes
from day to day.

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And so its position is changing
over the year.

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Also, you might think

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that it's because
the Earth is closer to the Sun

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that we have summer,
and farther away

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to give us winter,
but it turns out,

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it's actually
something different.

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It's not only the fact that
we have the Earth rotating

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and revolving,
but it's tilted on its axis.

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- We'll have you be the Sun.

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Up here now,
it's summertime

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in the Northern Hemisphere

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because the Northern Hemisphere
is receiving

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more direct sun rays
from the Sun.

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Down here, it's the wintertime
because those sun rays

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are indirect, or less direct
than up here.

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- So, because of the rotation
of the Earth,

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the tilt of the Earth,

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and its revolution
around the Sun...

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- We get the observable
patterns like day and night,

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and the seasons.

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- Check out this NASA website
to learn more

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about the connection between
the Sun and our world.

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See you next time.

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