| Term | Definition |
|---|
| geocentric system | a description of the solar system that the Greeks believed in which all of the planets revolve around Earth |
| heliocentric system | a description of the solar system in which all of the planets revolve around the sun; Copernicus believed in this |
| solar system | a large planetary system that consists of a combination of many smaller planetary systems and objects |
| ellipse | an elongated circle, or oval shape |
| inertia | tendency of a moving object to continue in a straight line or a stationary object to remain in place |
| gravity | the force that attracts all objects toward one another |
| nuclear fusion | the combining of 2 atomic nuclei to produce a single larger nucleus |
| core | center; on the sun this is where fusion occurs |
| photosphere | the inner layer of the sun's atmosphere; the part of the sun that we see |
| chromosphere | the middle layer of the sun's atmosphere |
| corona | outer layer of the sun's atmosphere |
| solar winds | electrically charged particles that stream from the sun's corona and are usually blocked by the Earth's atmosphere and magnetic field |
| sunspots | areas of gas on the sun that are cooler that the gases around them and the number varies every 10-11 years |
| prominences | reddish loops of gas that link different parts of sunspot regions |
| solar flares | explosions of hydrogen gas from the sun's surface that occur when loops in sunspot regions suddenly connect and increases the solar wind resulting in an increase in the number of particles that reach the Earth's atmosphere |
| terrestrial planets | the four planets that have rocky surfaces |
| rotation | the spinning motion of a planet on its axis |
| revolution | movement of the planet around the sun |
| retrograde rotation | rotating in the opposite direction from most other planets; Venus rotates in this way |
| greenhouse effect | the trapping of heat by the atmosphere |
| gas giants | the first four outer planets |
| comets | large chunks of ice and dust whose orbits can be very long, narrow ellipses |
| asteroids | 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 Mars & Jupiter where many asteroids are found |
| meteoroids | chunks of rock or dust in space |
| meteorites | meteoroids that pass through the atmosphere & hit Earth's surface |
| meteors | streaks of light we see in the sky caused by meteoroids' friction with the atmosphere |
| satellite | any natural or artificial object that revolves around an object in space |
| geosynchronous orbit | the orbit of a satellite that revolves around Earth at the same rate that Earth rotates |
Combine with other sets
Share on Facebook
Share on MySpace