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THE OUTER PLANETS
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the most brilliant mathematical triumphs, it turned out not to be the planet expected.

"Neptune is much nearer the Sun than it ought to be," is the authoritative way in which a popular historian puts the intruding planet in its place. For the planet failed to justify theory by not fulfilling Bode's law, which Leverrier and Adams, in pointing out the disturber of Uranus, assumed "as they could do no otherwise." Though not strictly correct, as not only did both geometers do otherwise, but neither did otherwise enough, the quotation may serve to bring Bode's law into court, as it was at the bottom of one of the strangest and most generally misunderstood chapters in celestial mechanics.

Very soon after Uranus was recognized as a planet, approximate ephemerides of its motion resulted in showing that it had several times previously been recorded as a fixed star. Bode himself discovered the first of these records, one by Mayer in 1756, and Bode and others found another made by Flamstead in 1690. These observations enabled an elliptic orbit to be calculated which satisfied them all. Subsequently others were detected. Lemonnier discovered that he had himself not discovered it several times, cataloguing it as a fixed star. Flamstead was spared a like mortification by being dead. For both these observers had recorded it two or more nights running,