Christoph Scheiner (1575-1650)
The Jesuit astronomer Christoph Scheinerwas born on July 25, 1575. He joined the Jesuitorder in 1595, and started his studies in 1601 at Ingolstadtwhere he later taught mathematics from 1610 to 1616.He moved to Innsbruck in 1616, was in Rome from 1624 to 1633, and died in Niesse on June 18, 1650. The above portrait is fromthe Stadt Müseum Ingolstadt.
The controversy between Scheiner and Galileo over priorityin the discovery of sunspots was an important factor(though not the only one) responsible for the degradation in the relationshipbetween Galileo and Roman members the Jesuit Order. By his own account Scheiner began observing sunspots in March or April 1611,together with his then assistant J.B. Cysat. The first published account of his observationsare his Three letters on Solar Spots (Tres epistolae de maculis solaribus), dated November 11, 1611,addressed to Augsburg magistrate Mark Wesler (1558-1614) andpublished in Augsburg in January 1612. These were followedby three more letters in September 1612, again published via Wesler. Scheiner was requiredby his ecclesiastic superiors to write under the pseudonymAppelles, to avoid possible embarrassment to the Jesuit order inthe event that his findings were to prove spurious.
Scheiner's original opinion was that sunspots were small planets closely orbiting the Sun, a position convincingly refuted byGalileo in his own 1632 Letters on Solar Spots.Unlike Galileo, Scheiner pursued sunspot observations on a continuousbasis for more than 15 years. In the course of doing so he devisedtechniques that greatlyimproved the accuracy of observed sunspot positions, and designed specialized solar observing instruments. Results of his observations werepublished in 1630 in his Rosa Ursina, a book four yearsin the making that opened with biting attack on Galileo, to whichthe latter was to reciprocate in his Dialogues.