Nicolaus Copernicus and Johannes Kepler:

Astronomers Extraordinaire

Notable Quotes:  

"Finally we shall place the Sun himself at the center of the Universe. All this is suggested by the systematic procession of events and the harmony of the whole Universe, if only we face the facts, as they say, `with both eyes open'."   Copernicus

1543 AD Copernicus publishes "De revolutionibus orbium coelestium" (On the revolutions of the heavenly spheres). This is the source of the Copernican theory, namely that the Sun (not the Earth) is at rest in the centre of the Universe.
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Biographical Info

Copernicus Bio Info MacTutor Site

Kepler Bio Info MacTutor Site


Copernicus Activities:

JPL Site with elementary age activities:


Kepler Activities:

Heavenly Mathematics: Cultural Astronomy

Hands On Universe Explorations

How Far Is It Quiz