| Word |
 |
|
| Definition |
|
|
| Terrestrial planets |
The name given to the four inner planets: Mercury, Venus, Earth, and Mars. |
| Retrograde rotation |
The spinning motion of a planet from east to west, opposite to the direction of rotation of most planets and moons. |
| Greenhouse effect |
The trapping of heat by a planet's atmosphere. |
| Gas giants |
The name given to the first four outer planets: Jupiter, Saturn, Uranus, and Neptune. |
| Comet |
A ball of ice and dust whose orbit is a long, narrow ellipse. |
| Asteroid |
Objects revolving around the sun that are too small and too numerous to be considered planets. |
| Asteroid belt |
The region of the solar system between the orbits of Mars and Jupiter, where many asteroids are found. |
| Meteoroid |
A chunk of rock or dust in space. |
| Meteor |
A streak of light in the sky produced by the burning of a meteoroid in Earth's atmosphere. |
| Meteorite |
A meteoroid that has hit Earth's surface. |
MedTemCP5 Word+Pics
