UC Irvine

SN 1006 was the first (and for a very long time the only) event to be caught before peak light. A passage which, according to Stephenson, does not actually pertain to the SN, nevertheless makes clear that, even then, a hypothesis was more likely to be accepted if it made a prediction later verified, though the prediction was that something bad would happen to Emperor Sanjo In. The hypothesis was that the star was not new, but related to behavior of existing stars in Qichen Jianjun. According to the poster by P.J. Boner, Kepler made the opposite choice for his SN, calling it a genuinely new star formed out of the ether, rather than mere change in appearance. Indeed the distinction between true novae and variable stars was not drawn correctly until Hevelius's 1662 study of Mira, after Tycho had shown that his event (and the comet of 1577) were more distant than our Moon, a point disputed by many of his contemporaries, but accepted by Galileo, who applied a very early statistical method to many different observations of SN 1572. Tycho's main advantages were better equipment and hard work, again not so different from present conditions. © 2007 International Astronomical Union.