THE STELLAR UNIVERSE. 



scarcely deserving the name of hypotheses or theories, we shall 

 leave them to be taken for what they are worth. 



TEMPORARY STARS. 



Phenomena in most respects similar to those just described, but 

 exhibiting no recurrence, repetition, or periodicity, have been 

 observed in many stars. Thus, stars have from time to time 

 appeared in various parts of the firmament, shone with extraordi- 

 nary splendour for a limited time, and have then disappeared 

 and have never again been observed. 



45. The first star of this class which has been recorded, is one 

 observed by Hipparchus, 125 B.C., the disappearance of which is 

 said to have led that astronomer to make his celebrated catalogue 

 of the fixed stars ; a work which has proved in modern times of 

 great value and interest. In the 389th year of our era, a star 

 blazed forth near o Aquilce, which shone for three weeks, ap- 

 pearing as splendid as the planet Venus, after which it disap- 

 peared and has never since been seen. In the years 945, 1264, 

 and 1572, brilliant stars appeared between the constellations of 

 Cepheus and Cassiopeia. The accounts of the positions of these 

 objects are obscure and uncertain, but the intervals between the 

 epochs of their appearances being nearly equal, it has been con- 

 jectured that they were successive returns of the same periodic 

 star, the period of which is about 300 years, or possibly half that 

 interval. 



The appearance of the star of 1572 was very remarkable, and 

 having been witnessed by the most eminent astronomers of that 

 day, the account of it may be considered to be well entitled to 

 confidence. Tycho Brahe, happening to be on his return on the 

 evening of the 1 1th November from his laboratory to his dwelling- 

 house, found a crowd of peasants gazing at a star which he was 

 sure did not exist half an hour before. This was the temporary 

 star of 1572, which was then as bright as the dog-star, and conti- 

 nued to increase in splendour until it surpassed Jupiter when that 

 planet is most brilliant, and finally it attained such a lustre, that 

 it was visible at mid-day. It began to diminish in December, and 

 altogether disappeared in March, 1574. 



On the 10th October, 1604, a splendid star suddenly burst 

 out in the constellation of Serpentarius, which was as bright as 

 that of 1572. It continued visible till October, 1605, when it 

 vanished. 



46. A star of the fifth magnitude, easily visible to the naked 

 eye, was seen by Mr. Hind in the constellation of Ophiuchus, on 

 the night of the 28th April, 1848. From the perfect acquaint- 



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