ASTRONOMICAL PHENOMENA AND PROGRESS. 



41 



.owing ni<jht it h:i<l apparently sunk from the 

 the :;d magnitude. On the night of the 

 1 tlli nf May it was studied at the Cambridge 

 M! was then reported to bo of 

 about the ::d magnitude. By the 19th its bril- 

 liancy had decrca-vd by nearly two magnitudes, 

 and it was then very near the limit of visibility 

 t<> the. naked eye. On the 20th it was no longer 

 iiil.lo to the unaided vision, but' could 

 he seen through an opera-glass. The 

 al dwindled to the 9th magnitude by the 

 '.i[h of June. The following was the table of 

 magnitudes as estimated by Mr. B. A. Gould, 

 iihridgo (American Journal of Science, 

 xlii., 124) : 



One observer in Philadelphia says that he saw 

 on the 23d of September, 1865, a brilliant star in 

 Corona, not laid down in the maps. It was 

 reported to have been seen in London, Canada 

 West, about May 1st, when its brilliancy was 

 about equal to that of e Coronro, or between 

 the 3d and 4th degrees of magnitude. It was 

 seen in Ireland and England on the 12th of 

 May, and in France on the 13th. The descrip- 

 tions of the star given by all the foreign ob- 

 servers at that time agree with those of the 

 various observers in this country. On the 16th 

 of May it was observed and subjected to the 

 spectrum analysis by "William Huggins, F. R. S., 

 anil W. A. Miller, Prof, of Chemistry in King's 

 College, London, whose applications of that 

 new power to the solution of some astronomical 

 problems have been among the most valuable 

 scientific results of the year. At that time the 

 magnitude of the new star was below the 3d. 

 In the telescope it appeared to be enveloped in 

 a taint nebulous haze, which extended to a con- 

 siderable distance and faded away at the boun- 

 dary. A comparative examination of neighbor- 

 ing stars showed that nebularity really existed 

 about it. Its spectrum was unlike that of any 

 other celestial body thus far examined. The 

 light was compound, and had apparently ema- 

 nated from two sources. The principal spectrum 

 was analogous to that of the sun, evidently 

 formed by the light of an incandescent solid or 

 liquid photosphere, which has suffered absorp- 

 tion by vapors of an envelope coolcrthan itself. 

 The second spectrum consisted of a few bright 

 lines, indicating that the light by which it was 

 formed was emitted by matter in the state of 

 luminous gas. To the eye the star appeared 

 nearly white ; but as it flickered there was seen 

 an occasional preponderance of yellow or blue. 

 The lines of the second spectrum indicated that 



the gas consisted chiefly of hydrogen. Obser- 

 vations were also taken on several successive 

 evenings, during which the continuous spectrum 

 diminished in brightness more rapidly than the 

 gaseous spectrum. Messrs. Huggins and Miller 

 suggest, as their explanation of these brilliant 

 phenomena, that, in consequence of some vast 

 convulsion, larger quantities of gas were evolved 

 from the star, that the hydrogen present was 

 burning in combination with some other ele- 

 ments, and that the flaming gas had heated to 

 vivid incandescence the solid matter of the 

 photosphere. As the hydrogen was consumed, 

 the phenomena would diminish in intensity and 

 the star rapidly wane. The results of the obser- 

 vations of Messrs. Huggins and Miller were con- 

 firmed by those of Messrs. Stone and Carpenter, 

 at the Royal Observatory, on the night of 

 May 19th." 



Humboldt, in his " Cosmos," gives the follow- 

 ing list of temporary stars, which are recorded 

 in history, with variable degrees of certainty as 

 to items : 



134 B. c., in Scorpio. 



123 A. D,, in Ophmchus. 



173 

 369 



886 

 389 

 393 



827 



945 

 1012 

 1203 

 1230 

 1264 

 1572 

 1578 

 1584 

 1600 

 1004 

 1609 

 1670 

 1848 



in Centauron. 



in Sagittarius. 



in Aquilla. 



in Scorpio. 



in Scorpio. 



between Cepheus and Cassiopeia 



in Aries. 



in Scorpio. 



in Ophiuchus. 



between Cepheus and Cassiopeia. 



in Cassiopeia. 



in Scorpio, 

 in Cygnus. 

 in Ophiuchus. 



in Vulnes. 

 in Ophiuchus. 



The majority of these stars shone with great 

 splendor when first seen. Only three of the 

 known variable stars, according to Humboldt, 

 have been less than the 1st magnitude at tha 

 height of their brilliancy. The star of 389 A. D. 

 was for three weeks as bright as Venus, and 

 then rapidly disappeared from view. That of 

 1572 was seen at mid-day on November llth, 

 and no longer visible in the following March. 

 It was as bright as Sirius, and reached the lustre 

 of Jupiter. The star of October, 1604, also 

 exhibited great splendor. The stars of 393, 

 827, 1203, and 1609, are considered one and 

 the same ; and a reappearance is predicted in 

 2014-'5. The periods of visibility of these stars 

 differ greatly. That of 389 was three weeks ; 

 of 827 'four months; and of 1012 three months. 

 Tycho Brahe's star in Cassiopeia (1572) shone 

 for 17 months. Kepler's star in Cygnus was 

 visible 21 years before it totally disappeared. 

 It was seen again (as a star in the same posi- 

 tion) in 1655, and was then of the 3d magni- 

 tude. 



The star of 1806 appears to be identified with 

 No. 2,765 of Argelander's IT-UQ + 26 marked 



