Astronomy 101 - Exam questions and
Verified Answers
Length of a lunar month - ANSWER 29.5 day cycle
Length of the Moon's orbit around the Earth - ANSWER 27.3 days
Length of the Moon's rotation on its axis - ANSWER 27.3 days
Why do we see phases of the Moon? - ANSWER the revolution of the moon around the
Earth allows us to see different amounts of the moon being illuminated
Why do we see the same face of the Moon from Earth? - ANSWER the moons rotation
period=moons orbital period. The moon has a heavy metal side
Three types of solar eclipses - ANSWER 1)total
2)partial
3)annular (moon is closer to the sun, get a ring)
Three types of lunar eclipses - ANSWER 1)total
2) partial
3)penumbral (lightest part of the shadow)
, What was Aristotle's idea for the universe? Why was he wrong? - ANSWER He was responsible
for the geocentric model of the universe.
Had sphere of fire, earth not at center, moon/sun not the same size
What was Ptolemy's idea for the geocentric model? How did he try to explain retrograde
motion? Why was he incorrect? - ANSWER Earth-centered, with planets moving in epicycles
around the earth. He explained this by adding epicycles, very complicated motion could be
explained.
It was incorrect because he assumed that all planets had circular motions.
What was Eratosthenes' contribution to astronomy? - ANSWER He measured the earths radius
about 23,000 years ago. And he noticed that when the sun was directly overhead in Syene
(Egypt) it was at an angle in Alexandria on summer solstice. (1% off)
What were Aristarchus' contributions to astronomy? - ANSWER He obtained distances to the
sun and moon.
First to have idea about heliocentric universe
What was Copernicus' idea for the Universe? How did he explain retrograde motion? - ANSWER
He produced the first comprehensive mathematical heliocentric model.
He explained retrograde motion in the projection effect, found distances of planets from
the sun.
Earth is in the fast lane of Mars.
Why was part of the Copernican idea wrong? - ANSWER He was partly wrong because he
assumed all planets had circular orbits.
What was Tycho Brahe's contribution to astronomy? - ANSWER Made accurate observations of
planets, a comet, and a supernova all without a telescope. (had a brass nose)
Verified Answers
Length of a lunar month - ANSWER 29.5 day cycle
Length of the Moon's orbit around the Earth - ANSWER 27.3 days
Length of the Moon's rotation on its axis - ANSWER 27.3 days
Why do we see phases of the Moon? - ANSWER the revolution of the moon around the
Earth allows us to see different amounts of the moon being illuminated
Why do we see the same face of the Moon from Earth? - ANSWER the moons rotation
period=moons orbital period. The moon has a heavy metal side
Three types of solar eclipses - ANSWER 1)total
2)partial
3)annular (moon is closer to the sun, get a ring)
Three types of lunar eclipses - ANSWER 1)total
2) partial
3)penumbral (lightest part of the shadow)
, What was Aristotle's idea for the universe? Why was he wrong? - ANSWER He was responsible
for the geocentric model of the universe.
Had sphere of fire, earth not at center, moon/sun not the same size
What was Ptolemy's idea for the geocentric model? How did he try to explain retrograde
motion? Why was he incorrect? - ANSWER Earth-centered, with planets moving in epicycles
around the earth. He explained this by adding epicycles, very complicated motion could be
explained.
It was incorrect because he assumed that all planets had circular motions.
What was Eratosthenes' contribution to astronomy? - ANSWER He measured the earths radius
about 23,000 years ago. And he noticed that when the sun was directly overhead in Syene
(Egypt) it was at an angle in Alexandria on summer solstice. (1% off)
What were Aristarchus' contributions to astronomy? - ANSWER He obtained distances to the
sun and moon.
First to have idea about heliocentric universe
What was Copernicus' idea for the Universe? How did he explain retrograde motion? - ANSWER
He produced the first comprehensive mathematical heliocentric model.
He explained retrograde motion in the projection effect, found distances of planets from
the sun.
Earth is in the fast lane of Mars.
Why was part of the Copernican idea wrong? - ANSWER He was partly wrong because he
assumed all planets had circular orbits.
What was Tycho Brahe's contribution to astronomy? - ANSWER Made accurate observations of
planets, a comet, and a supernova all without a telescope. (had a brass nose)
