New Planet, Ninth of Solar System, Discovered by Arizona Observatory---President Lowell's Brother Credited With Find

A hitherto unknown planet, the ninth of our solar system, has been located beyond Neptune by astronomers at the Lowell Observatory at Flagstaff, Arizona, according to an announcement made yesterday by the Harvard College Observatory. It was in search of this planet that Percival Lowell '76, an older brother of President Lowell, spent the last years of his life. As an interesting side-light, it was learned yesterday that the date of the discovery would have been his seventy-fifth birthday.

The new planet is probably larger than the Earth and smaller than Neptune, and can be seen only with the most powerful telescopes now in existence. It has been estimated that the sun's light at this farthest planet can hardly exceed that of moonlight, and under such a low temperature the nitrogen that might be in the air would be solid and the oxygen, if not solid, at least a dense liquid.

It was by means of photographs, through a new 13-inch "Triplet", the most powerful telescope of its class, that the discovery was made at the Lowell Observatory, and the Harvard Observatory, in its role of distributor of the astronomical news of the Western Hemisphere, is sending word of the discovery to the observatories of the other continents.

Percival Lowell, to whom the real credit must go for the discovery, founded the Lowell Observatory in 1894. At that time he was especially attracted by the problems of the markings on the planet Mars, and the Observatory has always devoted its of largely to that planet, and the planetary system. Astronomers have long known from the irregularities in the motions of the farthest planets that another existed still farther off. Some years before his death Lowell made some calculations to discover the position and the orbit of that planet, which were published in the proceedings of the American Academy of Arts and Sciences in 1915. Since that time his observatory at Flag-staff has been seeking it in the sky. Seven weeks ago a small object was observed, but it was not until yesterday, after seven weeks of constant observation, that the rate and the direction of the motion of this object showed that it could be certified to conform exactly to the orbit of the planet calculated by Lowell. Its position on March 12 agreed perfectly with the longitude which he had predicted.

The method of discovering this planet is surprisingly like that by which the planet Neptune was found in 1846 by the astronomer, Galle, at Berlin. Mathematical calculations had been made as to the position of this planet by Leverrier, a French astronomer, and by means of these it was discovered by Galle's telescope.