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Earth in Universe
Earth in the Universe/Space Race
Term | Definition |
---|---|
Rotation | The spinning motion of a planet on its axis |
Revolution | The movement of an object around another object. One complete __________ of Earth around the sun is called a year. |
Axis | An imaginary line that passes through Earth's center and the North and South poles, about which Earth rotates |
Galaxy | A huge group of single stars, star systems, star clusters, dust, and gas bound together by gravity |
Solar System | the collection of eight planets and their moons in orbit around the sun, together with smaller bodies in the form of asteroids, meteoroids, and comets. |
Planet | a celestial body moving in an elliptical orbit around a star. |
Atmosphere | the envelope of gases surrounding the earth or another planet. |
Satellite (natural) | an object that revolves around another object in space. |
Seasons | each of the four divisions of the year marked by particular weather patterns and daylight hours, resulting from the earth's changing position with regard to the sun. |
Solstice | The two days of the year on which the sun reaches its greatest distance north or south of the equator |
Equinox | The two days of the year on which neither hemisphere is tilted toward or away from the sun |
Orbit | The path of an object as it revolves around another object in space |
Equator | the line of latitude in the middle of the globe at 0 degrees/it divides the Northern and Southern Hemispheres |
Hemisphere | a half of the earth, usually as divided into northern and southern halves by the equator, or into western and eastern halves by an imaginary line passing through the poles. |
Counter-Clockwise | in the opposite direction to the way in which the hands of a clock move around. |
Low Latitude | The tropics |
Middle Latitude | All four seasons |
High Latitude | Polar Zones |
Gravity | The attractive forces between objects; its strength depends on their masses and the distance between them |
Isaac Newton | English mathematician and physicist; remembered for developing the calculus and for his law of gravitation and his three laws of motion (1642-1727) |
Force | A push or pull exerted on an object |
Mass | The amount of matter in an object |
Weight | A measure of the force of gravity acting on an object |
Inertia | The tendency of an object to resist a change in motion |
Newton’s First Law of Motion | An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force. |
Waxing | a gradual process of growth and development by the moon. |
Waning | the act of showing a gradually decreasing portion of illuminated surface, between full moon and new moon |
Gibbous | the act of showing a gradually decreasing portion of illuminated surface, between full moon and new moon |
Crescent | appears to be less than half of the moon lit up by the sun. |
Telescope | a device built to observe distant objects by making them appear closer. |
Asteroids | rocky objects revolving around the sun that are too small and numerous to be considered planets |
Meteors | a streak of light in the sky produced by the burning of a meteoroid in Earth’s atmosphere |
Comet | a loose collection of ice, dust and rocky particles, typically with a long, narrow orbit. |
Lunar Eclipse | an eclipse in which the moon appears darkened as it passes into the earth's shadow. |
Solar Eclipse | an eclipse in which the sun is obscured by the moon |
Umbra | The darkest part of a shadow |
Penumbra | The part of the shadow surrounding the darkest part |
Tides | The periodic rise and fall of the level of water in the ocean |
Space Probe | an unmanned exploratory spacecraft designed to transmit information about its environment. |
Satellite (artificial) | an artificial body placed in orbit around the earth or moon or another planet in order to collect information or for communication. |
Geosynchronous Orbit | an orbit in which a satellite orbits the Earth at the same rate as the Earth rotates and thus stays over the same place all the time |