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15 Cards in this Set

  • Front
  • Back
Celestial sphere
earliest model all the stars are attached surrounding the earth
formation/group of stars
measure the distance from a star
retrograd motion
planets look like they are going backwards
geocentric model of the solar system
earth in the center
only geocentric, whose center moves uniformly around the earth
larger circle around the earth
Ptolemy's model of the solar system
Geocentric Model
Heliocentric model of the solar system
sun is at the center
Copernican model of the solar system
Heliocentric model fo the solar system
Scientific Method
Refracting telescope
Just Lens
reflecting telescope
using a mirror
Kepler's three laws
1.All planets move in elipitcal paths
2.A line from the sun to the planet sweeps out equal areas in equal times
3.The square of a planets orbital period is proportional to the cube of its semi-major axis
Newton's law of gravity
calculated mass of planets