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Name: Mandy
Status: student
Age: 10
Location: N/A
Country: N/A
Date: 1999 - 2000


Question:
What makes the sun stay in space?


Replies:
Where else would it go? Are you thinking that it might fall down to the Earth? But the Sun is much, much bigger than the Earth. Maybe that doesn't make sense to you, because the Sun looks small up in the sky. But that's just because it is far away. You know that when you are up high in a building or in an airplane the cars and people on the ground look teeny tiny, like toys. It's the same way with the Sun: it only *looks* small because it is so very far away. But actually it's much bigger than the Earth. So it can't very well fall down to the Earth, can it? It's much more believable that the Earth might fall onto the surface of the Sun.

And it does, as a matter of fact. The Earth falls towards the Sun's surface all the time. But, you see, the Earth is also moving sideways, like a rock that is not dropped straight down but is thrown sideways. It turns out that by the time the Earth reaches where the Sun's surface was when the Earth started falling, the Earth has already gone past the edge of the Sun. That is, the Earth falls toward the Sun's surface, but misses it. Then the Earth comes around for another try, falling toward the *back* side of the Sun. And the Earth misses again. The Earth tries again from the front, and misses, and so on forever. What ends up happening is the Earth goes around and around the Sun.

The Earth doesn't miss hitting the Sun by as much during December and January, so it is closer to the Sun at that time than during June and July. That's why the winter in the North (during December) is not as cold as the winter in the South (during July).

Grayce



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