Which famous 17th-century astronomer and mathematician had to defend his mother at a witch trial?

Johannes Kepler (1571-1630) was a German mathematician, astronomer, and astrologer. A key figure in the 17th century scientific revolution, he is best known for his laws of planetary motion, based on his works Astronomia nova, Harmonices Mundi, and Epitome of Copernican Astronomy. The picture is of his model of the solar system.

In 1615, Ursula Reingold, a woman in a financial dispute with Kepler's brother Christoph, claimed Kepler's mother Katharina had made her sick with an evil brew. The dispute escalated, and in 1617 Katharina was accused of witchcraft. Beginning in August 1620, she was imprisoned for fourteen months. She was released in October 1621, thanks in part to the extensive legal defense drawn up by Kepler. The accusers had no stronger evidence than rumors. Throughout the trial, Kepler postponed his other work to focus on his 'harmonic theory'. The result, published in 1619, was Harmonices Mundi ('Harmony of the World')