| A | B |
|---|
| Refracting Telescope | Uses lenses to bring visible light to a focus |
| Reflecting telescopes | Use mirrors to bring visible light to a focus |
| Interferometry | the process of linking separate telescopes together so that they act as one telescope |
| Spinoffs | technologies that have been passes on to commercial industries for common use |
| albedo | the amount of sunlight that a surface reflects |
| highlands | Part of the Moon's surface which is light in color, mountainous, and havily covered with craters |
| impact craters | form when objects from space crash into the lunar surface |
| ejecta | material blasted during impacts that fell back onto the lunar surface |
| rays | long trails of ejecta that radiate outwards |
| rilles | meandering, valleylike structures on the lunar surface |
| regolith | a loose layer of ground-up rock on the lunar surface |
| ecliptic | the plane in which Earth orbits about the Sun |
| Summer Solstice | the Sun is directly overhead at the Tropic of Cancer during this yearly event |
| Winter Solstice | the SUn is directly overhead a the Tropic of Capricorn during this yearly event |
| Autumnal Equinox | Equal lengths of day and night which occurs during fall |
| Vernal Equinox | Equal lengths of day and night which occurs during the spring |
| Synchronous rotation | the state at which its orbital and rotational periods are equal |
| Perigee | the closest point in the Moon's orbit to Earth |
| Apogee | The farthest point in the Moon's orbit to Earth |
| Lunar Eclipse | occurs when the Moon passes through Earth's shadow |
| Maria/Mare | valleys, dark spots on the moon |
