Paula Vicki age 11, of Kershaw So. Carolina, for her question:
What is the orbit of the earth?
The earth’s orbit is its path around the sun. The path is a slight oval, almost round. You can make an oval with two pins, a pencil and a bit of string. Fix a pin to each end of the string and stick them upright in a flat board. Put the pencil through the loop of the string and stretch it out to the limit. Swing the loop around, making a pencil mark as you go. If your two pins stand quite, close together you have a rough picture of the earths orbit.
The sun's position is marked by one of the two pins. Along this side, the earth’s orbit, is slightly closer to the sun. In fact it is about three million miles closer. This seems like a vast distance but actually it is too small to make much difference.
The average distance, of the earths orbit from the sun is 93,005,000 miles. And the earth is three million miles closer in January than 2n July. The oval shape of the orbit does not cause the seasons.
The earth travels once around its orbit every year,. The actual time taken is 365 days, 5 hours, 48 minutes and 45,51 seconds. The distance the earth must travel every year is roughly 600 million miles. It travels a little faster where the orbit comes closest to the sun. But the average speed throughout the entire year is 182 miles a second, or 1083 miles a minute, or almost 65,000 miles an hour.
The earth with everything on it is racing around its orbit at this breakneck speed. Yet we are so used to it we do not even notice it. What's mores the earth is rotating around its axis. It spins around once every 24 hours, and we spin with it. And even this whirligig is not all.
The sun, the earth and the whole Solar System are moving through space. And this speed is the fastest of all. The sun is traveling in a vast orbit at the rate of 170 miles a second, and the earth goes with it.
The sun belongs to a vast system of stars called the Galaxy. It is shaped like a wheel and it turns like a wheel. Towards the center the wheel is thicker and the stars more numerous. The pale Milky Way we see in the sky is a view across the teeming center of the Galaxy. The pale light comes from billions of faraway stars.
Our sun is far from the center of the Big Wheel. It is about one third of the distances from the rim to the center. Out here the stars are fewer. And as the BIG Wheel rotates all the stars turn with it. Our sun is a star and it must travel its vast orbit around and around the Galaxy.
The earth's orbit is a small part of the big spin around the Galaxy. It forms a curlicue around the sun as the sun moves around its own giant orbit through the heavens. Meantime the moon is making an orbit around the earth. Around and around go the heavenly bodies dancing an endless hoedown in the heavens.