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- Did you know that the Sun is a star?
It's actually a star like stars that you see in the night sky.
But it's brighter than those other stars
because it's closer to us than any other star.
Let's go meet Dr. Alex Young and Dr. Nicki Viall.
I know that the Sun is our closest star,
but just how far away is it?
- Well, it's pretty far away.
It's 93 million miles away.
- And at that distance, it takes about eight minutes
for the Sun's light to reach the Earth.
- I know that the Sun rises and sets,
but where does it go when I can't see it?
- Well, the Sun doesn't actually go anywhere.
The Sun is always in the center of the solar system.
- So, that time it takes for the Earth to rotate
is 24 hours, and that's what we call a day.
- If Earth's rotation causes day and night,
what causes seasons?
- So, the seasons happen
because the Earth revolves around the Sun.
It travels all the way around the Sun and comes back.
- And the other thing that you're gonna find
is that, when you look out at the sky,
the location of the Sun changes from day to day.
And so its position is changing over the year.
Also, you might think
that it's because the Earth is closer to the Sun
that we have summer, and farther away
to give us winter, but it turns out,
it's actually something different.
It's not only the fact that we have the Earth rotating
and revolving, but it's tilted on its axis.
- We'll have you be the Sun.
Up here now, it's summertime
in the Northern Hemisphere
because the Northern Hemisphere is receiving
more direct sun rays from the Sun.
Down here, it's the wintertime because those sun rays
are indirect, or less direct than up here.
- So, because of the rotation of the Earth,
the tilt of the Earth,
and its revolution around the Sun...
- We get the observable patterns like day and night,
and the seasons.
- Check out this NASA website to learn more
about the connection between the Sun and our world.
See you next time.
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