标题: 《Styx and Stones, Maybe Charon Too 》作者：- George Harper【EPUB】 [打印本页] 作者: zaq 时间: 2013-9-26 18:22 标题: 《Styx and Stones, Maybe Charon Too 》作者：- George Harper【EPUB】 Styx and Stones, Maybe Charon Too - Analog Nov 73 George Harper ========== In 1766 the German mathematician, Johann Titius, wrote a brief footnote to a book on natural philosophy he was translating from the French. The book itself is long forgotten save for a few scholars, but the footnote has led a lively career. As translated by Stanley L. Jaki of Seton Hall University, it reads: “Divide the distance from the sun to Saturn into 100 parts; then Mercury is separated into 4 such parts from the sun; Venus by 4 + 3 = 7 such parts; the Earth by 4 + 6 = 10; Mars by 4 + 12 = 16. But notice that from Mars to Jupiter there comes a deviation from this exact progression. After Mars there follows a distance of 4 + 24 = 28 parts, but so far no planet or satellite has been found there… Let us assume that this space without a doubt belongs to the still undiscovered satellites of Mars… Next to this for us still unexplored space there rises Jupiter’s sphere of influence at 4 + 48 = 52 parts; and that of Saturn at 4 + 96 = 100.” Nor was this the first prediction of a planet between Mars and Jupiter. Nearly two centuries earlier, around 1595, Johannes Kepler penned the unambiguous sentence: Inter Jovem et Mortem planetum in-terposui , or “Between Jupiter and Mars I interpose a planet.” Either way, the mathematical relationship expressed by Titius and the prediction by Kepler remained curiosities until the summer