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28 Cards in this Set

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  • Back
What is the geocentric theory?
that the earth is the center of the Solar System
Who proposed the geocentric theory?
What was in Ptolemy's solar system?
Mercury, Mars, Venus. Jupiter, Sarurn, Earth, moon, sun, sphere of stars
What is the helicentric theory?
sun is the center of the solar system, moon revolve arund the earth and the earth around the sun, movement of the sun and stars is caused by the Earth's rotation
who proposed the heliocentric theory?
What are the inner planets?
Mercury, Venus, Earth, Mars
What is special about the inner planets?
closest to sun, rocky solid surfaces,like the earth (terrestrial)
What are the outer planets?
Jupiter, Saturn, Uranus, Neptune, PLuto
What are the gas giants?
Jupiter, Saturn, Uranus, Neptune
What are the gas giants made of?
swrling balls of gas, surfaces are slush from frozen gasses
what is pluto classified under?
not classified, appears to made of gasses frozen into ice
hwo did the solar system form
there was a nebulae (swirling cloud of ice and dust) gravity contracted %99 of the material into a tightly packed compact spinning disk, center was so hot because the gasses were put under pressure so nuclear fusion began and the sun was born, rest of the material clumped and the rest of the solar system was formed (because of solar wind)
Why are the inner planets closer and the outer planets farther away?
inner planets are heavy so it is harder to push them away and the outer are made of light gases so they were easy to push
What are the two forces that keep the planets in orbit?
inertia and gravity
how do gravity and inertia work together
gravity keeps the planets in orbit and inertia keeps planets from being drawn into the sun
what is kepler's law of planetary motion
elliptical orbits, sun is not centered in the orbit, closer planets travel faster around the sun than farther planets
Which planets travel faster around the sun, the inner or outer
the inner
What is an asteroid?
a chunk of rock not big enough to be a planet, found in asteroid belt between mars and jupiter, irregular haped, largest is Ceres
What is a comet?
a mass of rock and dust mixed with frozen wter, methane, and ammonia, two parts are tail and head
What are the two parts of the head??
nucleus- center of comet -coma-gas cloud around the comet
What is the tail of a comet?
gasses trailing behind the comet, formed by solar wind, points away from sun
zwhat is the difference between meteors, meteorites, and meteoroids
meteoroids are chunks of rock in space
meteors are meteoroids in the earth
meteorites are meteorids that don't burn and hits a planet
what is the order of the planets from biggest to smallest
jupiter, sturn, uranus, neptune,. earth, vennus, mars, mercury, pluto
why os the sky in Mercury black?
no atmoshere so no light can shatter whick mamkes our sky blue
why is venus the hottest planet
the carbon dioxide traps the heat in and doesn't let it out (greenohouse)
What planets have 0 moons
what planets have 1 moon
pluto, earth
who has the most moons
jupiter (61)