| A | B |
|---|
| astronomy | The study of the universe |
| universe | Everything that exists, including Earth, the planet, the stars, and all of space |
| telescope | A device that collects light and magnifies images to make distant objects appear closer and larger |
| rotation | One complete spin of an object such as Earth on its axis |
| standard time zone | A vertical belt about 15 degrees wide in longitude in which all places have the same time |
| international date line | The 180 degree line of longitude. Going west across this line adds one day to the date; going east subtracts a day |
| revolution | One complete trip orbiting around an object, such as Earth orbiting the sun |
| visible light | Light that you can detect with your eyes |
| refracting telescope | Uses lenses to gather light from a faraway object and magnify its image |
| reflecting telescope | Uses a series of two or more mirrors to reflect visible light which amplifies an image |
| invisible light | Any light frequency in the electromagnetic spectrum that people cannot see.EX. X-Rays and ultraviolet light |
| apparent path | The Sun's appearance of rising in the east and traveling west is called its ________________ |
| Artificial satellites | Scientists send _______________to study planet Earth. They can transmit data back to Earth with speed and accuracy |
| Space probes | _______________travel beyond Earth and use onboard instruments to study various objects in the solar system |
| Space shuttle | A reusable spacecraft |
| Hubble Space Telescope | Takes clear pictures of Earth because it orbits above most of Earth's atmosphere |
| Summer | The season when a hemisphere is tilted toward the Sun and receives the Sun's rays more directly |
| Winter | The season when a hemisphere is tilted away from the Sun and receives the Sun's rays at a lower angle |
| Shorter shadows | In summer when the Sun is overhead at midday,objects cast _________________ |
| Longer shadows | In winter,when the Sun is lower in the sky at midday,objects cast ______________ |
