Tycho's starA type I supernova that was observed in 1572 in the constellation Cassiopeia and was studied by astronomers in Europe, China, and Korea. Tycho Brahe's careful observations of its position have allowed modern astronomers to identify it with a known radio and X-ray source, which is the expanding supernova remnant. It was considerably brighter than Kepler's star of 1604, reaching a magnitude of –4 and remaining visible for about 18 months.
Collins Dictionary of Astronomy © Market House Books Ltd, 2006
Tycho's star[′tī·kōz ′stär]
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.