| A | B |
|---|
| Waning | describes phases that occur after a full moon, as the visible lighted side of the moon grows smaller. |
| Solar Eclipse | occurs when the moon passes directly between the Sun and Earth and casts a shadow over part of Earth. |
| Revolution | Earth's yearlong elliptical orbit around the Sun. |
| Sphere | A round, three-dimensional object whose surface is the same distance from its center at all points; Earth is a sphere that bulges somewhat at the equator and is slightly flattened at the poles. |
| Waxing | phases following a new moon, as more of the Moon's lighted side becomes visible. |
| New moon | phase that occurs when the Moon is between Earth and the Sun, at which point the Moon cannot be seen because its lighted half is facing the Sun and its dark side faces Earth. |
| Solstice | Twice-yearly point at which the Sun reaches its greatest distance north or south of the equator. |
| Rotation | Spinning of Earth on its imaginary axis, which takes about 24 hours to complete, and causes day and night to occur. |
| Ellipse | elongated, closed curve that describes Earth's yearlong orbit around the Sun. |
| Moon phase | change in appearance of the Moon as viewed from Earth, due to the relative positions of the Moon, Earth, and the Sun. |
| Lunar Eclipse | occurs when Earth's shadow falls on the Moon. |
| orbit | the circular path of an object as it revolves around another object |
| Full moon | phase that occurs when all of the Moon's surface facing Earth reftects light. |
| Equinox | twice-yearly time each spring and fall when the Sun is directly over the equator and the number of daylight and nighttime hours are equal worldwide. |
| Axis | imaginary vertical line that cuts through the center of Earth and around which Earth spins. |
