Unit 2 Flashcards
Aristotle
proposed theory that universe had two types of motion
Who proposed the two types of motion and what are they
Aristotle, towards/away and around
retrograde motion
occurs when planet appears to stop, go backwards, then forward, like on a track racing
epicycles
spheres within spheres
Ptolemy
able to predict the location of planets using Aristotle’s theories.
Aristarchus
believed that the sun was at the center of our solar system
heliocentric
sun center belief with earth and planets orbiting around.
Geocentric
earth centered theory
Eratosthenes
calculated the circumference of the Earth
Who proposed the idea of epicycles?
Ptolemy
Dark Ages
affected Europe after the fall of the Roman Empire
Who detailed the advantages of the sun centered theory
Nicolaus copernicus
Configurations
geometric arrangements
inferior conjunction
inner planets line up between Earth and Sun
Superior cunjunction
inner planets opposite side of the sun from Earth
Greatest eastern elongation
planet is as far east of the sun as it can be
Greatest western elongation
planet farthest west it can reach
opposition
planet opposite side of the sun, outer planets
conjunction
planet lined up with the sun, outer planet
period
amount of time it takes ot complete one revolution
synodic period
time elapsed between 2 successive configurations
sidereal period
true orbit period of planet
Johannes Kepler
proposed planetary orbits not circles
Keplers laws
- planets orbit in an ellipse
- Relationship between planet speed and sun distance
- sidereal period^2 =semi major axis^3
Who used the first telescope
Galileo Galilei
Isaac Newton
made three laws
Who proposed general relativity (idea that gravity curves)
Albert Einstein
gravitational lensing
curvature of space bends path of light
Orion
the hunter, shaped like a person bright stars Betelguese and Rigel
Canis Major
Great dog, shaped like a dog with four legs, bright start Sirius
Canis minor
little dog, a short line, bright start procyon
Auriga
the charioteer, shaped like a pentagon, bright start Capella
t/f
When Saturn is at opposition we cannot see it because it is hiding behind the Sun.
false
Aphelion is the point in a planetary orbit at which the planet is
farthest from the Sun
t/f
Epicycles are smaller spheres attached to the larger deferents.
true
Ptolemy
invented epicycles to explain retrograde motion
Eratosthenes
calculated the circumference of Earth
Aristotle
theory of the universe with two types of motion: towards away from and around
Aristarchus
believed that the Sun was at the center of the universe
Galileo Galilei
first astronomer to use a telescope
Tycho Brahe
tried to prove heliocentric universe was wrong
Nicholas Copernicus
first modern astronomer to believe in a heliocentric universe
Johannes Kepler
theorized that planets do not move at uniform speeds throughout their orbits
t/f
Most of the names of the brightest stars are of Arabic origin.
true
Who proposed the idea that gravity could actually bend light?
Albert Einstein
t/f The synodic period is the amount of time for a planet to move from one configuration to the next identical configuration.
true
t/f All early astronomers before Copernicus believed that the world was flat
false
t/f Planets in orbits closer to the Sun move faster than planets in orbits further away.
true
t/f Planets do not orbit the Sun in perfectly circular orbits.
true
Which of the following is not one of the major astronomical discoveries made by Galileo?
The shape of a planet’s orbit is an ellipse.
t/f Astronomers of ancient Greece believed the world was shaped like a sphere.
true
What was the greatest contribution of Tycho Brahe to astronomy?
He amassed a large number of precise measurements of stellar and planetary positions in the sky.
