 Here we are zooming into the surviving companion star to a titanic supernova explosion witnessed in the year 1572 by the great Danish astronomer Tycho Bra. On November 11, 1572, Tycho Bra noticed a star in the constellation Cassiopeia that was as bright as the planet Jupiter. No such star had ever been observed at this location before. It soon equaled Venus in brightness. For about two weeks, the star could be seen in daylight. At the end of November, it began to fade and change color, from bright white to yellow and orange to faint reddish light, finally fading away from visible light in March 1574. Tycho's meticulous recording of the brightening and dimming of the supernova now allow us to identify its light signature as that of a Type 1A supernova.