Download Famous Astronomers

Name: ______________________________________________________ Period: _______ Date: ____________
Famous Astronomers
Directions: Match the famous astronomer to the quote that makes the most sense.
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Tycho
Galileo
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Kepler
Ptolemy
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Hubble
Copernicus
1) “I’ve finally worked out a mathematical explanation as to why
planets orbit the sun and moons orbit planets. It is gravity that
keeps an object in orbit!”
2) “The Earth is the center of the universe, and all of the planets and
stars orbit our planet. How do I know? Well, my theory includes an
intricate system of orbits within orbits that explains the motion of
the planets better than any other theory of my day.”
3) “Using large telescopes, I’ve discovered that all the other galaxies
out there are moving away from us; in other words, the universe is
expanding, as if it exploded in some sort of ‘Big Bang’! Gee, I sure
hope someone names a famous space telescope after me
someday!”
4) “I prefer the theory of the sun-centered universe over other
theories. This handy device called a telescope has helped me to
discover that the planets are not just dots of light, but physical
bodies like the Earth.”
5) “After several years of very precise observations, I conclude that
our universe is Earth-centered. My model has the sun and the
moon revolving around the Earth, while the other planets revolve
around the sun.”
6) “For centuries people have been thinking that the Earth is at the
universe’s center, but I’m certain that it is, in fact, the sun at its
center. This heliocentric model is the simplest explanation for the
strange retrograde motion of the planets across the sky.”
7) “I do not agree with my mentor’s theory that the sun revolves
around the Earth. I have used his precise data to propose another
theory in which all of the planets revolve around the sun in
elliptical orbits.”
8) “As one of the most famous ancient Greek philosophers, I asked
questions about the universe and our place in it. Many people
consider me to be one of the first scientists ever.”
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Newton
Aristotle
Geocentric vs. Heliocentric Models
1) Explain what’s going on in this picture:
Retrograde Motion of Mars
2) What are the differences between the geocentric and heliocentric models?
Ptolemy’s
model
Copernicus’
model:
3) How does each model explain the retrograde motion of the planets?
4) “Occam’s Razor” is the principle that given two possible explanations, the simplest one is usually the
correct solution. How does this principle apply to these two models?