The New Intra-Mercurial Planet

The New Intra-Mercurial Planet

M. Gaillot of the Paris Observatory has compared the position of the planet discovered by Watson and Swift with those which would result from the four possible orbits assigned by Leverrier two years since from a consideration of the observations at various times of unknown bodies seen transiting the sun's disc by trustworthy observers. He has found that one of them accords quite well with the recent observed position, but singularly it is that orbit which assigns Vulcan a period of revolution around the sun, of twenty-four days, which is less than the period of rotation of the sun on its own axis. The calculations of M. Gaillot must however be accepted with a great deal of reserve, since they are based on a somewhat erroneous position of Watson's planet. Moreover the question of identity can probably be settled only by future observation.

In a later number of the Comptes Rendus, Prof. Watson gives a correction of his first announced position, and announces that he observed also a second object also of the 4th magnitude, and obtained a position, which, however, he was not able to verify before the totality ended. The position of this second object is different from that of the neighboring star Theta Cancri; but as to its nature Prof. Watson expresses no opinion. In fact the whole notice in regard to this second object is obscure.

While on this subject of Vulcan it may be mentioned that M. Vinot gives in the Comptes Rendus for Aug. 12th, a letter received from Leverrier in Sept. 1876, in which the latter speaks favorably of the probability of there being two intra-mercurial planets.