Brahe_Tycho9

Nova
 * ~ Right Ascension || 00 : 25.3 (h:m) ||
 * ~ Declination || +64 : 09 (deg:m) ||
 * ~ Distance || 10,000 (ly) ||
 * ~ Visual brightness || -4 (mag) ||

On November 11th 1572, Tycho came across a bright star in the constellation Cassiopeia. He was observing the works of Herrevad Abbey on this day. Cassiopeia was named SN (Super Nova) 1572. A supernova (plural supernovae) is a stellar explosion that is more energetic than a nova. Most people believed that from the old times, fixed stars were eternal and unchangeable. Also, many other observers believed that the phenomenon was something in the Earth’s atmosphere. Tycho, however, observed that the apparent motion of the object did not change from night to night, suggesting that the object was too far away. Tycho argued that a nearby object should appear to shift its position with respect to the background.  Tycho also published a small book on this topic, //De Stella Nova// (1573), thus coining the term nova for a "new" star. We now know that Tycho's star was a supernova. This discovery was key for his choice of astronomy as a profession. Tycho was strongly critical of those who dismissed the sights of the astronomical appearance, writing in the preface to //De Stella Nova//: "O crassa ingenia. O caecos coeli spectatores" ("Oh thick wits. Oh blind watchers of the sky").