Johannes Kepler

Astronomer Extraordinaire


Johannes Kepler was born in 1571, to Lutheran parents. Although he studied about theology in divinity, he was recommended to teach math and astronomy. His first astronomical model (shown on the left) was a model of the solar system that explained how all the planets fit together.


  • First to explain the orbit of Mars.
  • First to suggest that the sun rotates on its axis.
  • First to explain planetary motion.
  • First to fully address the cause of celestial motion.
  • First to measure the distance from stars using stellar parallax.
  • First to explain how a telescope works.
  • First to create eyeglasses designed for nearsightedness and farsightedness.

Impact on Today

  • Kepler's three laws of motion are still used by astronomers today.
  • Without all of the evidence that Kepler found supporting the Copernican theory (heliocentric), we might still believe that the Earth is the center of the universe.

Interesting Facts

  • Worked about a year for Tycho Brahe.
  • Kepler's 2nd law of planetary motion was discovered before the first.
  • Died in 1630, while on a trip to Bavaria.

Project Citation

Works Cited

Primary Sources

“Model of the Universe.” Johannes Kepler: From “Mysteries” to “Harmony.” Golden Museum, n.d. Web. 6 Mar. 2014. <>.

Secondary Sources

Brandenburger, Barry Max. “Solar System Geometry, History of.” Mathematics. Ed. Barry Max Brandenberger. New York: Macmillan Reference, n.d. N. pag. Biography in Context. Web. 27 Feb. 2014. <>.

January, Brendan. Science in the Renaissance. N.p.: Franklin Watts, 1999. Print.

“Johannes Kepler.” Biographical Encyclopedia of Scientists. Ed. Richard Olson and Roger Smith. Tarrytown: Marshall Cavendish Corpration, 1998. N. pag. Print.

Wilson, Martin. “Kepler’s List of Achievements.” Johannes Kepler Info. N.p., n.d. Web. 28 Feb. 2014. <>.