Читать книгу Triumphs and Wonders of the 19th Century: The True Mirror of a Phenomenal Era - James P. Boyd - Страница 32
III. HOW NEPTUNE WAS FOUND.
ОглавлениеThe patience of Job had a strong parallel in the labors of those tireless toilers to whose minute computations we owe our knowledge of Neptune’s path in the skies. For this far-off planet was discovered not by the use of a telescope, or any optical instrument, but simply by a process of mathematical reasoning. The story is simply this. For sixty years after Uranus was recognized, there were irregularities in its motion that could not be satisfactorily accounted for. In the orbit that it was believed to pursue, it was sometimes in advance of its proper position, and sometimes it seemed to fall behind. Sometimes it appeared to be drawn a little to the right, and at other times as far the other way.
The thought at last came separately to several penetrating minds, not that the observations of its position were in error, but that Uranus must be drawn away from its supposed path by the attraction exercised upon it by some unseen body. And if such an object existed, was it a planet? Where was it? How large was it? What was its path in the far-off ether?
THE MOVEMENT OF URANUS AND NEPTUNE.
The inner circle shows the position of Uranus at various dates; the outer circle the position of Neptune. The arrows show the direction toward which Uranus was drawn.
In the year 1842, the Royal Society of Sciences of Göttingen proposed as a prize question the full discussion of the theory of the motions of Uranus. It was specially sought to learn the cause of the large and increasing error of Bouvard’s Tables that had been relied upon to show its motion and its precise position at any time. Several able mathematicians undertook this intricate problem. Among them were John C. Adams, of Cambridge University, England, Sears C. Walker, of Washington, a man whose sad fate it was to pass away ere his magnificent abilities could receive extended recognition, and M. Le Verrier, of Paris. Working unknown to each other, they reached similar conclusions almost at the same time. Though not the first to solve the problem, the brilliant Frenchman was the first to announce his result, which he did by writing a letter to Dr. Galle, of the Berlin Observatory, where there was one of the largest telescopes in Europe, and asking him to search for his computed planet, and assigning its supposed place in the heavens. The very night he received the letter Dr. Galle found the planet within one degree of the point designated. The next night it had moved one minute of space, and was also seen to have a perceptible disk. This settled the question, and stamped it as a planet. Le Verrier well merited the title bestowed upon him, “First astronomer of the age.”