Chapter 2: The Rise of Astronomy. Ancient Roots: Early Homo-Sapiens. Ancient Roots: Egyptian. Ancient Roots: England. Ancient Roots: Mayan. Ancient Roots: Aztec. Ancient Roots: Incan. Ancient Roots: Cambodia. Ancient Roots: Anasazi. Early Ideas: Pythagoras.
The Rise of Astronomy
But model couldn’t account fully for retrograde motion of the planet!!!
Tried to account
motion, but could
Copernicus devised the first comprehensive helio-centric cosmology to successfully explain retrograde motion
Kepler’s First Law: The orbit of a planet about the Sun is an ellipse with the Sun at one focus.
Kepler’s Second Law: A line joining a planet and the Sun sweeps out equal areas in equal intervals of time.
In other words, the closer a planet is in its orbit around the Sun, the faster its speed is.
In other words, the planets that are
closest to the Sun orbit the Sun at a faster
speed than planets that are farther away.
The orbit of a planet about the Sun is an ellipse with the Sun at one focus
The closer the planet is in its orbit around the
Sun, the faster its speed is.
The planets that are closest to the Sun orbit the Sun at a faster speed than planets that are farther away.
Summary of Kepler’s Laws of Planetary Motion
Italian scientist Galileo made discoveries that strongly supported a helio-centric cosmology
“I do not feel obliged to believe that the samegod who has endowed us with sense, reason andintellect has intended us to forgo their use.” - Galileo
Galileo’s telescope revealed that Jupiter had moons which orbited Jupiter instead of Earth.
Galileo’s telescope revealed all phases of Venus which could only occur IF Venus orbits the Sun.
What goes up,
must come down!
remains the same everywhere
pulled down while on the ground (due to gravity’s attraction)
changes depending on the body you are