Week 2 :
On Location : Discovery Channel Telescope
I. Waltz of our planets
I. a) Survival Skills
"First you guess. Don't laugh, this is the most important step. Then you compare the consequences to experience. If it disagrees with experience, the guess is wrong. In that simple statement is the key to science. It doesn't matter how beautiful your guess is or how smart you are or what your name is. If it disagrees with experience, it's wrong. That's all there is to it."
Richard Feynman
Notes
Scientific thinking : trial and error observation with experiments.
Ancient cultures used the sky to tell the time and to locate themselves.
The hands of a clock turns in a clockwise manner, as the shadow on a sundial would.
7 days ? => 7 objects moving in the sky : planets + Sun
Freya's day (Venus) = Friday, Tiu's day (Mars) = Tuesday, Woden's day (Mercury) = Wednesday, Thor's day (Jupiter) = Thursday, barbaric who invaded Rome.
I. b) Circles on circles
"Give us matter and a little motion, and we will construct the universe."
Ralph Waldo Emerson
Notes :
Greek's method : create a logical and mathematical model, test it, make predictions, make sure it's falsifiable and try to proove it wrong
Alexandria -> the greek culture was omnipresent.
9 muses :
|
Calliope : Epic poetry |
Euterpe : Secular music |
Thalia :
Comedy |
|
Erato : Lyric poetry |
Polyhymnia : Religious music | Melpomene : Tragedy |
|
Clio : History |
Terpsichore : Dance | Urania : Astronomy |
In 200 BC, Claude Ptolémée (Ptolemy) synthesized all the greek astronomy in 13 books called the "Great Composition"
► "Mathematical syntaxis"
► "Great Composition" ► "Almagest"
▬► This book was translated in Latin and Arabic, it was largely diffused.
The geocentric model was remplaced 1700 years later.
He explained the retrograde motion with the Deferent-Epicycle cercles theory
:
The planets turns on the Epicycle, which turns on the Deferent
cercle.
It's the "circles on circles" principe
I. c) Nicolaus' Revolution
"Since nothing prevents the earth from moving, I suggest we should now also consider whether several motions suit it, so that it can be regarded as one of the planets. For, it is not the center of all the revolutions."
Nicolaus Copernicus
Notes :
t
I. c) An empirical beginning
Notes :
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