Tycho Brahe days list. One should also note that Denmark was on the Julian calendar until 1700, when it switched to the Gregorian calendar. Medieval calendars often contained lists of "dies Ægyptiaci", "Egyptian days", that also were held to be unlucky. The Egyptian days were: These too were days considered unlucky to begin any enterprise. Physicians were especially discouraged from performing bloodletting on the Egyptian days. Tycho Brahe days In the folklore of Scandinavia, Tycho Brahe days (Danish: "Tycho Brahes-dage"; Norwegian: "Tycho Brahedager"; Swedish: "Tycho Brahe-dagar") are days judged to be especially unlucky, especially for magical work, and important business transactions[ and personal
Tycho Brahe "Rudolphine Tables". Also at the court in Prague was the mathematician Nicolaus Reimers (Ursus), with whom Tycho had previously corresponded, and who, like Tycho, had developed a geo-heliocentric planetary model, which Tycho considered to have been plagiarized from his own. Kepler had previously spoken highly of Ursus, but now found himself in the problematic position of being employed by Tycho and having to defend his employer against Ursus' accusations, even though he disagreed with both of their planetary models. In 1600, he finished the tract "Apologia pro Tychone contra Ursum" (defense of Tycho against Ursus). Kepler had great respect for