Johannes Kepler

Johannes Kepler (December 27, 1571 – November 15, 1630), a key figure in the scientific revolution, was a brilliant German mathematician, astronomer and astrologer. He is best known for his laws of planetary motion, expounded in the two books Astronomia nova and Harmonices Mundi.

Life

Kepler was born on December 27, 1571 at the Imperial Free City of Weil der Stadt (now part of the Stuttgart Region in the German state of Baden-Württemberg, 30 km west of Stuttgart's so center). His grandfather had been Lord Mayor of that town, but by the time Johannes was born, the Kepler family fortunes were in decline. His father earned a precarious living as a mercenary, and abandoned the family when Johannes was 17. His mother, an inn-keeper's daughter, had a reputation for involvement in witchcraft. Born prematurely, Johannes is said to have been a weak and sickly child, but despite his ill health, he was precociously brilliant - he often impressed travelers at the inn with his phenomenal mathematical faculty as a child.

Related Topics:
December 27 - 1571 - Imperial Free City - Weil der Stadt - Stuttgart Region - Baden-Württemberg - Mercenary - Witchcraft

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Though he excelled in his schooling, Kepler was frequently bullied, and was plagued by a belief that he was physically repulsive, thoroughly unlikable and, compared to the other pupils, an outsider. This ostracizing probably led him to turn to the world of ideas, as well as an abiding religious conviction, for solace.

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He was introduced to astronomy/astrology at an early age, and developed a love for that discipline that would span his entire life. At age six, he observed the Comet of 1577, writing that he "...was taken by mother to a high place to look at it." At age nine, he observed another astronomical event, the Lunar eclipse of 1580, recording that he remembered being "called outdoors" to see it and that the moon "appeared quite red."

Related Topics:
Comet - 1577 - Lunar eclipse - 1580

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In 1587, Kepler began attending the University of Tübingen, where he proved himself to be a superb mathematician. Upon his graduation from that school in 1591, he went on to pursue study in theology, becoming a part of the Tübingen faculty. However, before he took his final exams he was recommended for the vacant post of teacher of mathematics and astronomy at the Protestant school in Graz, Austria. He accepted the position in April of 1594, at the age of 23.

Related Topics:
1587 - University of Tübingen - 1591 - Theology - 1594

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In April 1597, Kepler married Barbara Müller. She died in 1611 and was survived by two children.

Related Topics:
1597 - 1611

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In December 1599, Tycho Brahe wrote to Kepler, inviting Kepler to assist him at Benátky nad Jizerou outside Prague. After Tycho's death, Kepler was appointed Imperial Mathematician (from November 1601 to 1630) to the Habsburg Emperors.

Related Topics:
1599 - Tycho Brahe - Benátky nad Jizerou - Prague - 1601 - 1630

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In October 1604, Kepler observed the supernova which was subsequently named Kepler's Star. In January 1612 the Emperor died, and Kepler took the post of provincial mathematician in Linz.

Related Topics:
1604 - Supernova - Kepler's Star - 1612 - Linz

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In 1611, Kepler published a monograph on the origins of snowflakes, the first known work on the subject. He correctly theorized that their hexagonal nature was due to cold, but did not ascertain a physical cause for this. The question of snowflakes was not resolved until the 20th century.

Related Topics:
1611 - Snowflakes - 20th century

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On March 8, 1618 Kepler discovered the third law of planetary motion: distance cubed over time squared. He initially rejected this idea, but later confirmed it on May 15 of the same year.

Related Topics:
March 8 - 1618 - May 15

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In August of 1620, Katherine, Kepler's mother, was arrested in Leonberg as a witch; she was imprisoned for 14 months. She was released in October 1621 after attempts to convict her failed. Even though she was subjected to torture, she refused to confess to the charges. However, only the courageous personal intervention of Kepler (despite the risk to be arrested as well) and his reputation as the famous Imperial Mathematician rescued her.

Related Topics:
1620 - 1621 - Torture

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On November 15, 1630 Kepler died of a fever in Regensburg.

Related Topics:
November 15 - 1630 - Regensburg

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In 1632, only two years after his death, his grave was demolished by the Swedish army in the Thirty Years' War.

Related Topics:
1632 - Swedish - Thirty Years' War

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