Its interesting to know!

It's interesting to know why.

A few facts about the Earth and the Air.

* Why the air does not stop the light of the sun.

The air stops a great deal of the light of the sun. The sun and 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.

* 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 which 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.

* Does the equator go round faster than the poles?

Any point of the equator must move faster than a point near the poles, because the earth spins as a ball with a needle through its centre. The earth spins round once in twenty-four hours. A point which is one mile from the poles spins less than four miles a day. But on the equator, which is more than 24,000 miles round, a point spins a thousand miles an hour.

* Has the earth 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, as the sun has.

But now the earth hasn't 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.