| A | B |
|---|
| asteroid | a rocky or metallic object that orbits the Sun |
| fault | a break or crack in the rocks of the lithosphere along which movements can take place |
| constellation | a group of stars that appears to form a pattern |
| telescopes | a device that collects light and magnifies images to make distant objects appear closer and larger |
| gravity | the force of attraction among all objects |
| light-year | the distance that light travels in one year |
| meteoroid | a small rocky object that orbits the Sun in both the inner and outer regions of the solar system |
| Milky Way | the medium-sized spiral galaxy that is our home galaxy |
| rotation | one complete spin of an object such as Earth on its axis |
| supernova | an exploded star |
| refracting telescope | a telescope that uses lenses to gather light from a far away object and magnifies its image |
| reflecting telescope | Visible light reflects off a series of two or more mirrors which amplify the image before it reaches lenses in the eyepiece of a _____________ _________________ |
| standard time zone | a vertical belt about 15 degrees wide in longitude in which all places have the same time |
| International Date Line | an imaginary line that separates two consecutive calendar days which sits on the 180 degrees line of longitude in the middle of the Pacific Ocean |
| Foucault Pendulum | a heavy ball hung by a long wire with a device attached to the ball that could trace the pendulum's path across sand designed by a French scientist to show the Earth's rotation |
| spring tide | When the Sun, Earth, and Moon are all in a line a ______________ ______________ occurs. The high tides are higher than usual and the low tides are lower than usual at this time |
| Waxing | The phases of the Moon when the lighted side of it becomes more and more visible |
| Waning | The phases of the moon when less and less of the lighted side of it is visible |
| maria | large, dark, flat surface areas on the Moon |
| craters | bowl shaped depressions on the Moon's surface |
| highlands | light colored regions near the lunar poles |
| mountains | found around the edges of large maria and named after mountains ranges on Earth |
| valleys | cigar shaped depressions on the Moon's surface |
| weathering | the breaking down of rocks into smaller pieces by natural processes |
| absolute age | a rock layer's age in years |
| seafloor spreading | the moving apart of plates on the ocean floor that is caused by magma flowing up between the plates and then hardening |
| relative age | the age of a rock layer determined by comparing it to other rock layers |
| continental drift | the slow movement of the continents over eons |
| hydrosphere | the part of the Earth that contains water |
| erosion | the picking up and removal of rock pieces and other particles |
| vent | a central opening through which magma and gases erupt once reaching Earth's surface |
| lithosphere | the crust and the rigid part of Earth's mantle |
| big bang theory | the beginning moment when the universe was very hot and dense resulting in a tremendous explosion |
