Page:Popular Science Monthly Volume 41.djvu/412

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398
THE POPULAR SCIENCE MONTHLY.

chus on April 28, 1848. When first noticed it was about the fifth magnitude. It afterward rose to nearly the fourth magnitude, but gradually faded away. Hind was certain that up to April 3rd or 5th no object of even the ninth magnitude was visible in the position of the new star. This curious object is still visible, but has become very faint in recent years. In 1866 it was of the twelfth magnitude, and in 1875 not above the thirteenth magnitude.

On May 28, 1860, a new star was discovered by the late Mr. Pogson in the globular cluster known as 80 Messier in Scorpio. When first seen it was about the seventh magnitude, and nearly blotted out the nebula by its superior light. On June 10th the star had nearly vanished, and the cluster again shone out with its usual brilliancy, and with a condensed center. Pogson observed the cluster on May 9th, and noticed nothing remarkable; and, according to Schönfeld, it presented its usual appearance on May 15th in the heliometer of the Königsberg Observatory.

The star of 1866, known as the "Blaze Star," suddenly appeared in Corona Borealis in May of that year. Although it was subsequently found that the object had been previously observed and registered as a small star by the famous German astronomer, Argelander, it presented at the time of its discovery all the characteristics of a true nova. It seems to have blazed out very suddenly, for at about 9.30 p. m. on the evening of the 12th of May in that year Prof. Schmidt, observing the constellation Corona Borealis at Athens, saw nothing peculiar. Indeed, he afterward expressed his conviction that at that hour a star of even the fifth magnitude could not possibly have existed near the position without immediately attracting his attention. Within three hours afterward—about midnight—it was discovered by the late Mr. Birmingham, at Tuam, Ireland, shining as a star of the second magnitude, and rivaling in brilliancy Alphecca, "the gem of the coronet." Its light, however, rapidly faded. On May 14th it was of the third magnitude; on May 19th, only of the sixth. On May 24th it had become invisible to the naked eye, and by June 9th had faded to the ninth magnitude. When near its greatest brightness its light was examined by Dr. Huggins with the spectroscope, which showed the bright lines of hydrogen gas in addition to the ordinary stellar spectrum. During the ten years following this extraordinary outburst of light, Schmidt observed fluctuations in its brightness, which appeared to take place with a certain regularity. It would therefore seem that this object should be considered as an irregular variable rather than a "temporary star." Its rejection from the list of "new stars" would remove the only exception to the rule that all these wonderful objects have appeared in or near the Milky Way. Even the new star which was ob-