Rensselaer Union, Volume 10, Number 36, Rensselaer, Jasper County, 23 May 1878 — The Transit of Mercury. [ARTICLE]

The Transit of Mercury.

It is yet too soon even to conjecture, with anything like certainty, what results will flow from the many observations made of the planet Mercury’s recent transit across the face of the sun. Two points of importance are certain, namely, that the weather was particularly favorable for the making of observations, and that every availaable telescope of the country' was used, with the best aids to varied and accurate observation that could be provided. There are several astronomical questions which these observations are intended to solve, in whole or ip part, but two Of them so outweigh the others that their solution may be said to be the object sought by all the astrono mers. One of these is the question of the sun’s distance from the earth—a question the full, accurate and conclusive answer to which would furnish the I. means of solving by accurate calculation a vast body of mathematical problems with reference to the solar system, and would at once greatly advance astronomical science in its store of facts and in the accuracy of its com-1 potations. For purposes of this kind the recent transit of Mercury was far

lew valuable to astronomers than the late transit of Vonua, but it is hoped atleast that the observations of Mercury may correct or oonfinn the results obtained at the time of Venus’ transit and may thus narrow still furthor the margin of doubt which exists with respect to the exact distance between the sun and the earth. By far the most interesting question which was sought to be answered yesterday, however, was whether or not there is a planet nearer the sun than Mercury is. Le Verrier, whose mathematical calculations revealed the existence and the place of one planet before it was seeu, thought that the existence of still another planet, revolving within the orbit of Mercury, was shown by certain peculiarities of Mercury’s motion. The existence or non-exist-enceof this inter-Mercurial planet was from the first a matter of profound curiosity among astronomers, and the more because certain trustworthy observers have believed that they have seen the supposed planet, while the accuracy of their observations has not been confirmed by others which ought to have confirmed it if they were right in believing that they had seen the new planet. Without attempting to give more than the most popular statement of the matter, we may say that to solve this question it was necessary to discover whether or not the planet Mercury shows increased motion at its perihelion—that is to say, in that part of its orbit which brings it nearest the sun—as Le Verrier supposed. Upon this supposed increased motion Le Verrier’s theory of the existence of an interior planet rested. It is not to be expected, of course, that an exact agreement will appear between the results of the observations made in various parts of the country, because the condition of the atmosphere and many other circumstances may affect the accuracy of so nice a matter at any given station; but the Washington observations which were made with the very best apparatus at hind, show pretty conclusively an increased motion even greater than that on which Le Verrier founded his calculation, and so far as reports have been received the observations made at other points generally confirm this conclusion. The figures are yet to be worked out in many places, comparisons are to be made, and the exact results will not be known immediately, but the indications are pretty clear that Le Verrier’s theory will prove to be correct. Prof. Peters, of Hamilton College, in this State, believes that he has made an interesting discovery in observing the transit, namely, that Mercury has an atmosphere. Sis full report on this point will be awaited with much interest. If the indications upon which he founds his belief shall prove to be satisfactory to himself and to his fellow astronomers when examined critically, Prof. Peters will have made a contribution of moment to the store of astrdnoraical facts which American observers have so greatly’ enriched of late years.—A. ¥. Evening Post.