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14 Cards in this Set

  • Front
  • Back
In his model of the solar system Copernicus..?
Included epicycles because he assumed that the planets move at constant speeds.
Tycho Brahe's main contribution to astronomy was..?
His many accurate observations.
Kepler's first law states that..?
A planet's path around the Sun is an ellipse, with the Sun at one focus of the ellipse. However, Kepler's second law implies that a planet's speed around the Sun is not constant.
Kepler's second law states that..?
states that planets do not move uniformly in their orbits.
Kepler's third law allows us..?
Allows us to find the relative distances of the planets from the Sun.
"The greater the orbit of a planet around the Sun, the longer it takes the planet to complete a revolution" is an accurate description of what?
Keplers third law.
The Copernican model of the heavens differed from that of the ancient Greeks in that in the Copernican model..?
Was heliocentric.
Who suggested a model for the solar system that was a mix between the models of Ptolemy and Copernicus?
Tycho Brahe.
Who observed a supernova?
Tycho Brahe.
Ptolemy introduced epicycles in his model in order to explain..?
The observed retrograde motions of the planets.
Eratosthenes was able to measure the Earth's radius by..?
By measuring the length of shadows at two different locations on Earth a known distance apart.
One of the reasons that Aristarchus' heliocentric model was not accepted was that..?
Tt could not explain why parallax was not observed.
The observation that supports the idea that the Earth revolves around the Sun is..?
The observation of parallax for stars.
In order for a scientific hypothesis to be valid, there must be a way for proving it: True or false?
False, A scientific hypothesis is an educated guess that must be testable and, at least in principle, it must be susceptible to being shown wrong. Nothing in science can be proven to be correct for all time.