| A | B |
|---|
| Astronomy | The study of moon, stars, and other objects in space. |
| Axis | The imaginary line that passes through the Earth’s center and the North and South poles. |
| Rotation | the spinning motion of a planet about its axis. |
| Revolution | The movement of one object around another object. |
| Orbit | The path of an object as it revolves around another object in space. |
| Latitude | The measure of distance from the equator, expressed in degrees north or south. (The Equator has a latitude of 0° and the North Pole has a latitude of 90° north.) |
| Solstice | the two days of the year on which the noon sun is directly overhead at either 23.5° South or 23.5° North. |
| Equinox | “Equal Night” - The length of the nighttime and daytime are about the same. |
| Vernal Equinox | Spring Equinox – March 21, the beginning of Spring in the Northern Hemisphere. |
| Autumnal Equinox | Fall Equinox – September 21, the beginning of Fall in the Northern Hemisphere. |
| Phase | the different shaped of the moon you see from Earth. |
| Penumbra | The part of a shadow surroundings the darkest part. |
| Solar Eclipse | when the moon passes between the Earth and the sun, blocking the sunlight from reaching Earth. |
| Lunar Eclipse | occurs at a full moon when Earth is directly between the moon and the sun. |
| Gravity | the attractive force between two objects; its magnitude depends on the masses and the distance between them. |
| Satellite | any natural or artificial object that revolves around an object in space, just as the moon revolves around Earth. |
| Telescope | A devise built to study distant objects by making them appear closer. |
| Crater | A round pit on the moon’s surface. |
| Maria | Dark, flat regions on the moon’s surface. |
