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22 Cards in this Set
- Front
- Back
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Events such as days, years, seasons, eclipses, tides, and moon cycles can be explained by...
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the regular and predictable motions of objects in the solar system
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What dominatnt force keeps planets in orbit around the sun and determines the motions in the solar system?
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gravitational force
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What determines the length of a day on Earth?
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the time it takes Earth to rotate on its axis
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What determines the length of any palnet's year?
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the time it takes any planet to orbit the sun
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Do comets have a circular or elliptical (oval shaped) orbit?
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elliptical
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Is the sun in the center of a comet's elliptical orbit or more toward one end of the oval shaped orbit?
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more toward one end of the oval shaped orbit
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What might a person on Earth see when a meteroroid enters the Earth's atmosphere?
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a bright streak across the sky that some people refer to as a shooting star
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What happens to a meteroid when it enters the Earth's atmosphere that causes it to burn up?
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Friction between the meteroid and particles of matter in the atmosphere generates a lot of heat which build up quickly causing the meteorite to burn.
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How are asteroids classified into one of three groups?
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Classification is based on their composition (make up).
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List the three types of asteroids.
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carbonaceous (C-type)
silicaceous (S-type) metallic (M-type) |
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What are carbonaceous asteroids made of and what percent of all asteroids do they comprise?
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entirely stone, 75%
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What are silicaceous asteropids made of and what percent of all asteroids do they comprise?
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a mix of rock and metal, 15%
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What are metallic ateroids made of and what percent of all asteroids do they comprise?
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iron and nickle, 10%
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What is the asteroid belt?
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a donut shaped, orbital ring between Mars and Jupiter where most asteroids orbit
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Do all asteroids orbit the sun at the same speed?
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No, each orbits the sun at its own speed.
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Do all asteroids remain in the asteroid belt?
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No, some asteroids travel in orbits other than the belt. For example three small groups of asteroids have orbits closer to the sun.
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What objects in space are referred to as "dirty snowballs" and why?
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Comets are called this because they are small chunks of dust and rocks held together by ice.
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Why are comets invisible from Earth?
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Comets are too small to be seen from earth; their nucleus (the solid part of them) is only a few kilometers across.
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When can a comet be seen from Earth?
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when it approaches the sun and some of the ice turns to gas forming a glowing head called a coma
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Name one major difference between an asteroid and a comet.
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Their compositions are a major difference. A comet is comprised of ice, dust and rock. Asteroids may be comprised of rock and/or metal but no ice.
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How is a comet's orbit different than an asteroids?
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A comet's orbit is far more elliptical and intersects the main plane of the solar system at an angle.
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What mnemonic device can be used to remember the names and order of our solar system's planets?
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My Very Excellent Mother Just Sent Us Nine Pizzas (Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto)
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