Astronomical Words

An asteroid is very similar to a comet - it is a large rock that orbits the sun. Comets have a tail, while asteroids do not. Smaller rocks, from the size of a grain of sand to a large bounder are called meteoroids. When they enter the Earth's atmosphere, they are called meteors. If they hit the ground, they are called meteorites. The photo is of a meteorite.

The atmosphere is the mixture of gases that surrounds the Earth, mostly nitrogen and oxygen. These gases protect us from the sun's radiation and make up air, which we breathe.

In astronomy, an eclipse is where various planetary bodies align and block the light from the sun. In a lunar eclipse, the Earth comes between the sun and the moon. In a solar eclipse, the moon comes between the Earth and the sun. The picture is of a solar eclipse. In general language, you eclipse someone if you do something so much better or more obviously than they do that everyone notices you and not them, for example "her beauty eclipsed all others at the dance".

A meteor is a firey streak that can be seen in the sky when a meteoroid enters Earth's atmosphere. Meteors are often called shooting stars.

An orbit is the path that an object follows around another object, especially a planet or other celestial body. For example, Earth orbits the sun, and satellites orbit Earth.