1571 – 1630
The nature of planetary orbits
How do you find the position of a planet (say
Mars) when you know its direction but not its distance
Standard surveying solution:
Observe it from two different
locations and use “triangulation” or parallax.
The motion of the Earth lets you make
observations from two different positions, but Mars moves
too during this time.
Kepler’s special insight:
Find an artificial way to make Mars