Examples

Animations

Retrograde Motion

http://www.lasalle.edu/~smithsc/Astronomy/retrograd.html

The Ellipse

http://www.mathopenref.com/ellipse.html

From Aristotle to Newton

A graphical and animated journey

Cast of Characters

Perceived observations of early observers - things that their model had to incorporate

Three incorrect assumptions held back the development of modern astronomy from the time of Aristotle until the 16th and 17th centuries:

¢ The Earth is the center of the Universe

¢ There is only uniform circular motion in the heavens

¢ Objects in the heavens are made from a perfect, unchanging substance not found on the Earth.

Kepler's Second Law

All of Kepler's Laws