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Astronomy Vocab1
Term | Definition |
---|---|
Astronomy | the branch of science that deals with celestial objects, space, and the physical universe as a whole |
Geocentric | having or representing the earth as the center, as in former astronomical systems |
Heliocentric | having or representing the sun as the center, as in the accepted astronomical model of the solar system |
Ellipse | a regular oval shape |
Astronomical Unit(AU) | a unit of measurement equal to 149.6 million kilometers, the mean distance from the center of the earth to the center of the sun |
Rotation | the action of rotating around an axis or center |
Revolution | the movement af an object around something |
Perihelion | the point in the orbit of a planet, asteroid, or comet at which it is closest to the sun |
Aphelion | the point in the orbit of a planet, asteroid, or comet at which it is furthest from the sun |
Phases of the Moon | the shape of the illuminated portion of the Moon as seen by an observer on Earth |
Solar Eclipse | an eclipse in which the sun is obscured by the moon |
Lunar Eclipse | an eclipse in which the moon appears darkened as it passes into the earth's shadow |
Terrestrial Planet | a planet that is composed primarily of silicate rocks or metals |
Jovian Planet | gas giant planets including Jupiter, Saturn, Uranus, and Neptune |
Asteroid | a small rocky body orbiting the sun |
Comet | a celestial object consisting of a nucleus of ice and dust and, when near the sun, a “tail” of gas and dust particles pointing away from the sun |
Meteoroid | a small body moving in the solar system that would become a meteor if it entered the earth's atmosphere |
Meteor | a small body of matter from outer space that enters the earth's atmosphere, becoming incandescent as a result of friction and appearing as a streak of light |
Meteorite | a meteor that survives its passage through the earth's atmosphere such that part of it strikes the ground |
Electromagnetic Spectrum | the range of wavelengths or frequencies over which electromagnetic radiation extends. |
Photon | a particle representing a quantum of light or other electromagnetic radiation |
Doppler Effect | an increase (or decrease) in the frequency of sound, light, or other waves as the source and observer move toward (or away from) each other |
Refracting Telescope | a telescope that uses a converging lens to collect light |
Reflecting Telescope | a telescope in which a mirror is used to collect and focus light |
Radio Telescope | an instrument used to detect radio emissions from the sky, whether from natural celestial objects or from artificial satellites |
Hubble Telescope | The Hubble Space Telescope is a large telescope in space. NASA launched Hubble in 1990. Hubble is as long as a large school bus. |
Space Shuttle | a rocket-launched spacecraft, able to land like an unpowered aircraft, used to make repeated journeys between the earth and earth orbit |