| A | B |
|---|
| Axis of rotation | an imaginary line about which Earth turns |
| Revolution | the motion of one object around another |
| Season | patterns of temperature changes and weather trends over the course of a year |
| Equinox | occurs when sunlight shines equally on the northern and southern hemispheres |
| Solstice | In an orbit, a position and time during which one hemisphere gets its maximum area of sunlight, while the other hemisphere gets its minimum amount; the time of year when days are either longest or shortest, and the angle of sunlight reaches its maximum or minimum. |
| Mare | a dark area on the Moon |
| Eclipse | occurs when a shadow makes the Sun or the Moon seem to grow dark |
| Umbra | The dark, central region of a shadow, such as the cone of complete shadow cast by an object. |
| Penumbra | A region of lighter shadow that may surround an umbra |
