A Few Facts about the Earth and the Air

Why does the air not stop the light of the sun?

The air stops a great deal of the sun’s light.

The sun, the moon, and the stars look much brighter when we go up in an airplane, or look at them through a telescope on a mountain, where their light has to pass through less air to reach our eyes.

If there were no air, the light and heat of the sun would be much greater than they are now.

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Does everything in the air move with the Earth?

Of course it does.

The air goes round with the Earth, as the seas go round with the Earth, and everything that is swimming in them.

Everything in the air moves with it, except such things as an airplane or a bird, which have their own power of movement.

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Does the equator go round faster than the poles?

Any point on the equator must move faster than a point near the poles, because the Earth spins like a ball with a needle through its center.

The Earth spins once in twenty-four hours. A point that is one mile from the poles spins less than four miles a day. But on the equator, which is more than 24,000 miles around, a point spins about a thousand miles an hour.

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Does the Earth have its own light like the Sun?

The Earth had its own light long ago. Scientists think that the other planets also had their own light, like the Sun.

But now the Earth does not have its own light, because it has become cool, while the Sun remains hot. So the Earth cannot give out its own light, but can only reflect the Sun’s light.