Western Civilization II / Unit 5 WC2 0408 short lesson, about 20 seconds
Galileo's Telescope and The Starry Messenger, 1610
Captions available
The idea
Galileo built a telescope from a description and saw the moon's craters, the sun's spots and Jupiter's moons, publishing The Starry Messenger in sixteen ten and demonstrating in public. The witness adds the phases of Venus and his claim that nature's laws are mathematical.
In practice
Imperfect heavens, an uncentered earth, ancients wrong.
Where people slip
Three assumptions undermined at once; the trial followed the third.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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