Kepler’s Horizon and Foci were inspired by Johannas Kepler’s work in the field of optics and light and by his three laws of planetary motion.
The history of astronomy is bookmarked by leaps in thinking, leaps resulting from the challenge of a fundamental assumption. Copernicus challenged the Ptolemaic notion that the earth was at the centre of the universe and replaced the earth with the sun. Kepler challenged the notion that heavenly bodies orbited in perfect circles and replaced the circle with the ellipse. In doing so he ripped tortuous complexities out of the explanations of planetary motion and introduced physics into the heavens.