History (lectures- Flashcards
What did the Mesopotamians do well?
Used “cuneiform” script on clay tablets to keep detailed records of everything including the sky/astronomical knowledge
What was the mathematical system the Babylonians used?
Base 60
What were the Babylonians’ contributions to astronomy? (Egyptians similar with less continuity)
360 day calendar, 360 degree angular measure, 24 hour day, 60 second minutes & 60 minute hours developed some trigonometry
What did the Greeks contribute to astronomy?
First to make MODELS of the natural world including the orbits etc. Tried to use math and mechanics WITHOUT mythology to explain natural phenomena
HOWEVER - Still using perfect circles & earth-centric view, believed the earth did not move and the stars/planets moved around it
What did Alexander the Great do for astronomy?
Conquered Mesopotamia and translated all the tablets: 2000+ years of astronomical information
(passed on to ARISTOTLE his uncle)
What did Pythagoras do for astronomy?
Pythagorean theorem, Explained music/strings/waves, stated that the whole world could be explained by math
What did Aristarchus do for astronomy?
Estimated relative size and distances of the Earth, sun and moon
First to put the sun at the center of the solar system!
Said that the stars were far away
HOWEVER - Still no evidence of the earth moving
What did Aristotle (and Plato) do for astronomy?
- Ideas dominated by friction, came up with the first theories that rest= natural state of an object & constant force is required to keep it moving
- First serious geometric cosmic model (“Spheres within Spheres”
HOWEVER - Astronomical bodies described as concentric spheres (wrong)
Still using perfect circles (wrong)
What did Eratosthenes do for astronomy?
Calculated the circumference of the earth by looking at the highest point of the sky on a certain day in two different locations
What did Hipparchus do for astronomy?
“Best of the ancient observers”
- invented modern magnitude (brightness) systems; bright = closer, dim = farther away
- epicycles, mini side quest rotations in a planets orbit (actually the tiny loops in retrograde motion)
-“Standard candle”
What is a Standard Candle
Object where the intrinsic lumosity is known (known brightness variable)
What did Ptolemy do for astronomy?
Holds record for longest-standing theory of the universe
Earth-centric
Venus= epicycle between earth and sun
What did Alfonso the X do for astronomy?
Had things translated for all languages
What were “The Dark Ages”
Economic, intellectual, and cultural decline or stagnation. Not many new discoveries, Church LOCKED Ptolemy and Aristotle’s ideas into their doctrine
What were Copernicus’s contributions to astronomy?
Improved calculations - true distances of planets from sun
potentially heliocentric?
found the regularity between the radius of an orbit & time it takes to go around the sun (later becomes T^2 = R^3 law)
