Johannes Kepler



            Born prematurely in 1571 on the waning side of a family fortune, Johannes Kepler was forced to find his own way in the world.  His father, a mercenary, was presumed dead after disappearing during the Eighty Year’s war between Spain and the Netherlands.  His mother was practiced in healing and herbology and was later tried for witchcraft.  Despite being considered a weak and sickly child, Kepler wasted no time in impressing travelers who visited his maternal grandfather’s inn with his intelligence.  After having witnessed the Great Comet of 1577 and the lunar eclipse of 1580, Kepler was fascinated by the astronomical world.  Unfortunately for Kepler, smallpox left him with poor sight and crippled his hands.

            When he had finished his public, Protestant schooling, he began to attend the University of Tübingen, studying theology.  He excelled at mathematics and continued his studies of philosophy and science where he learned of the debate between the Ptolemaic and Copernican systems of the solar system.  He was able to defend the heliocentric (Copernican) system from both the religious and theoretical positions and was persuaded upon his graduation to give up his desire to be a minister and become a teacher of mathematics at the Protestant school in Graz, Austria, later to be known as the University of Graz.

            One of the first works he put forth was the Mysterium Cosmographicum that primarily supported the Copernican heliocentric solar system model.  In his model he was able to show that each of the known planets could be placed inside of each other if they were assigned to concentric geometric shapes in the following order: octahedron, icosahedron, dodecahedron, tetrahedron, cube, Kepler was able to design spheres that were roughly the size of the known orbits of the planets.  Kepler was obsessed with showing that God had designed the universe along some complex mathematical lines and that it would be possible to unlock the secrets of the universe through math.  The Kepler polyhedrons are the result of trying to find the innate order of the universe through geometry.  He even went so far as to show that there was a direct relationship between the size of the planet and their orbit path, a fact that he eventually rejected, though it helped him to complete his work on planetary motion.

            In the years that he worked on his book, he met and married his wife, Barbara Müller.  Her father was not in favor of the union, despite his noble stature, mainly due to his poverty.  After he published his work he consented, but almost withdrew when Kepler was gone promoting his book.  After urging from the church, Jobst Müller, allowed his daughter to marry Johannes in 1597.  They had five children together, though the first two died in infancy.

            Kepler’s work took him to the observatories of Tycho Brahe.  Despite a bitter feud that evolved quickly, Kepler relied on Brahe for technical and financial support.  Though he could not start working for Brahe due to political and religious problems in his hometown, Kepler eventually caught up with Brahe when Brahe served in the court of Rudolph II, the Holy Roman Emperor.  Brahe had overcome the severe debates with Ursus and had put aside his feelings for Kepler so that they could both gain from the relationship, a trend that would be strained at times.  When Brahe died in 1601, Kepler quickly took advantage of the situation to obtain the long-desired tables of Brahe’s observations that had been closely guarded by Brahe in life.  He spent the next eleven years as Tycho Brahe’s successor in the royal court of Rudolph II.

            The years that Kepler spent in the court of Rudolph II were some of his most productive.  During this time he published the Rudolphine Tables (predictions of planetary observations) based on Brahe’s observations of Mars, worked with optics to describe parallax, the inverse square law, the cause of and observations of eclipses and relative distances of celestial bodies.  In 1604, he identified a super nova (SN1604) and published work about astrological symbols like the great conjunctions (pairing of planets in the observable sky, specifically, Jupiter and Saturn).  Galileo began a correspondence with Kepler and even requested that Kepler succeed him when he left the University of Padua in Italy, though Kepler declined the invitation.

            In 1611, despite having a family ravaged by sickness (wife Hungarian spotted fever and all three children with smallpox) Kepler created an improved telescope after the model Galileo created.  His second-youngest son and his wife died that year from their illnesses.  This was also the year that Rudolph II’s brother, Matthias, forced Rudolph II to hand over the throne to the Holy Roman Empire.  This action allowed Kepler to move to Linz where he taught and was part of the meetings that chose to spread the Gregorian calendar throughout the German lands.  In 1613, Kepler remarried this time to Susanna Reuttinger and continued his work on the Rudolphine Tables, a job that would not be complete until 1623 and weren’t printed until 1627.

            Though the acceptance of Kepler’s work was mixed, he managed to correctly produce much of the groundwork of what we know about the universe.  His search for an orderly state in the universe that was based in mathematics was at the route of all of his work while his religious background disallowed his work from recognizing the presence of an all-powerful creator who governed the world in a way that defied all convention.  His work allowed men like Tycho and Galileo to gain further reputation and others like Newton and eventually Einstein to gain a foothold on their studies of the natural phenomenon of the world.  The grave of Johannes Kepler was lost to the world when a conquering army plundered the churchyard that housed his body, but his work will continue to drive the scientific community to try and unlock the secrets that are hidden right in front of us.


Kepler’s original ideas about the universe led him to design a series of polyhedrons that were bound by spheres representing the orbit of the known planets.


The Supernova Remnant observed by Kepler in 1604 as seen through (from left to right) high energy X-ray, low energy X-ray, visible and IR.  The large photo is an overlapping of the four images at the bottom.


Kepler’s work with three-dimensional polyhedrons led to incredible expansion of geometry.