Nicholas Copernicus

• heliocentric model
• retrograde motion explained (animation)

Tycho Brahe

• nova stella discovery; present views here and here (X-ray vision)
• precision astrometry

Johannes Kepler & Kepler's Laws

1. Orbits are ellipses
2. Equal areas in equal times (animation, another animation)
3. P² = a³

• solar system orbit viewer
• inner solar system objects in real time

Galileo Galilei: Astronomer

• Galileo reporting to the funding agency
• Observations
  • Moons of Jupiter (animation)
  • Venus phases: Ptolemaic vs Copernican predictions
    observed phases

Galileo Galilei: Physicist

• Free body motion
• Free fall ("Tower of Pisa" experiment)