Before modern technology allowed astronomers to determine the exact distances between the Earth and other objects in the solar system, they had to rely on alternative methods to make these measurements. Two scientists who made some of these early measurements were Johannes Kepler and Giovanni Cassini. Kepler used the time of a planet’s orbit to determine the relative distance between the Earth and other objects, while Cassini used the parallax method to estimate distances. Johannes Kepler was born in 1571 in a small town called Weil der Swadt in Swabia, Germany and is well known for discovering the three laws of planetary motion. In 1589 he began his college level education in Tubingen at the Protestant university there. In his graduate studies, Kepler was taught by Michael Maestlin, a mathematical professor, who was one of the first believers of the heliocentric theory by Copernicus. This helped shaped his beliefs on the solar …show more content…
Kepler then went on to become a professor of mathematics himself at the Protestant seminary in Graz. There, Kepler taught arithmetic, geometry, Virgil and rhetoric and in his free time pursued astronomy and astrology. Kepler published an essay called The Cosmographic Mystery in 1597 where he used the five known regular solids to determine the distances of the planets from the Sun by assuming that a planet’s orbit was simultaneously circumscribed and inscribed in another. In 1600, Kepler became Tycho Brahe’s assistant. Tycho Brahe built instruments to measure the positions of the planets. Together they calculated the orbits of the planets. After Tycho Brahe’s death, Kepler took over his studies and was appointed Imperial Mathematician (the highest position in the field of mathematics in Europe). In 1609,