Chandra low x-ray image in red of SN 1572 (Tycho's Supernova, Tycho's Nova), B Cassiopeiae (B Cas), or 3C 10, shows expanding debris from the supernova explosion. SN1572 is a supernova of Type Ia in the constellation Cassiopeia, one of about eight supernovae visible to the naked eye in historical records. It burst forth in early November 1572 and was independently discovered by many individuals. The appearance of the Milky Way supernova of 1572 was perhaps one of the two or three most important events in the history of astronomy. The "new star" helped to revise ancient models of the heavens and to inaugurate a revolution in astronomy that began with the realized need to produce better astrometric star catalogues (and thus the need for more precise astronomical observing instruments). The supernova of 1572 is often called Tycho's supernova, because of the extensive work De nova et nullius aevi memoria prius visa stella (Concerning the Star, new and never before seen in the life or memory of anyone) that contains both Tycho Brahe's own observations and the analysis of many other observers. Release date April 26, 2011.