38 



ASTRONOMICAL PHENOMENA AND PROGRESS. 



BUD'S limb, where it suddenly disappeared at 

 4 h - 50 m ' 58*-, Cape mean time. 



Elements of the comet were computed by 

 Professor S. C. Chandler, of Cambridge, Mass. ; 

 Dr. Hind, of London, Eng. ; Mr. Corrigan, of 

 Washington, D. C. ; Professor H. A. Howe, of 

 Denver, Col., and many others. A striking 

 resemblance between these elements and those 

 of the comets of 1668, 1843, and 1880, was at 

 once noticed, suggesting the identity of the 

 four bodies. This hypothesis was provisionally 

 accepted by several astronomers, who account- 

 ed for the rapid shortening of the period by 

 the comet's motion in perihelion through the 

 corona, or the outermost strata of the solar at- 

 mosphere. Should this theory be verified, the 

 comet's career must evidently soon terminate 

 in a collision with the sun. 



The resemblance of the elements of the com- 

 ets of 1668 and 1882 is seen by the following 

 comparison : 



The similarity of elements is no less strik- 

 ing in the case of the comets of 1843 and 1880. 

 Mr. Chandler, however, assigns to the comet of 

 1882 a period of over eight years, or more than 

 three times the interval between the appari- 

 tions of 1880 and 1882 a fact unfavorable to 

 the theory of identity. On the other hand, 

 the " Astronomische Nachrichten," No. 2,430, 

 has some new researches on the orbit of the 

 great comet of 1880, by Dr. M. W. Meyer, of 

 Geneva, Switzerland researches which have 

 an important bearing upon this question of or- 

 bital convergence. Dr. Meyer finds the period 

 of Gould's comet (1880 I.) to be somewhat less 

 than thirty-seven years, or equal to the inter- 

 val between its own perihelion passage and 

 that of the great comet of 1843. Dr. Meyer 

 accordingly regards the two apparitions as re- 

 turns of the same body. Professor Hubbard 

 assigned the comet of 1843 a period of more 

 than five hundred years. It becomes, there- 

 fore, Dr. Meyer remarks, a matter of much im- 

 portance that the observations of the comet of 

 1843 be rediscussed, to determine whether they 

 can be reconciled with the short period of thirty- 

 seven years. If not, he concludes that the accel- 

 eration of the comet's motion may have been 

 due to its passage through the sun's atmosphere. 



The spectroscopic examination of Gould's 

 comet exhibited both the sodium and the car- 

 bon lines. "The spectrum of the nucleus," 

 says Professor Young, "consisted of a fairly 

 bright continuous spectrum, overlaid by the 

 usual carbon bands, and one or two lines. 

 The D-line was distinctly seen, and seen double, 

 but was faint and hard to catch. The fourth 

 carbon band in the violet was also faint. The 



brightest carbon band (near 5) was very bright 

 and beautifully defined, showing clearly the 

 three bright lines in it, which were seen in 

 the great comet of 1881. A direct comparison 

 with the blue base of the flame of a small wax- 

 candle showed a perfect coincidence between 

 its bands and those of the comet. No dark 

 lines were visible in the comet spectrum. The 

 cometary bands were easily seen all through 

 the head of the comet, and, "by opening the slit, 

 could be traced a long distance into the tail." 



The observations of several astronomers 

 seemed to indicate that parts of this comet 

 had become, or were becoming, detached from 

 the nucleus. Dr. Julius Schmidt, Director of 

 the Observatory of Athens, Greece, announced 

 the discovery, on October 8th, of a telescopic 

 comet only four degrees southwest of the great 

 comet, and moving in the same direction. In 

 the " Sidereal Messenger " for November, Mr. 

 William R. Brooks, of Phelps, N. Y., states 

 that while sweeping in the region of the great 

 comet, on the morning of October 21st, he dis- 

 covered a cometary mass eight degrees east of 

 Gould's comet. Its length was about two de- 

 grees. On the 15th of October, Professor 

 Young, of Princeton, noticed a nebulous stripe, 

 about half a degree wide, extending from the nu- 

 cleus toward the sun a distance of four degrees. 



The greatest apparent length of the tail ot 

 Gould's comet was from 15 to 18, and its 

 true length probably about 50,000,000 miles. 



In the "Science Observer" for November 

 15, 1882, Mr. Chandler gives elements derived 

 from all available observations from September 

 18th to October 20th. The period indicated 

 is much longer than that which he had previ- 

 ously calculated. The theory, therefore, that 

 the great comet of 1882 is identical with that 

 of 1880 has been generally abandoned. 



Mr. E. E. Barnard, of Nashville, Tenn., dis- 

 covered another comet on September 10th. It 

 was circular, with some central condensation, 

 and its light was equal to that of a star of the 

 tenth magnitude. From the observations ob- 

 tained from September 14th to October 7th, 

 Mr. Hind, of England, calculated the following 

 elements: 



Perihelion passage, November 13 '0067, G. M. T. 



Longitude of perihelion 354 47'6' 



Longitude of ascending node 249 8 9 



Inclination 83 43-1 



Perihelion distance. . 88.000,000 miles. 



Motion Retrograde. 



These elements have no decided resemblance 

 to those of any other known comet. 



EXPECTED RETURN OF THE COMET OF 1812. 

 The period assigned this comet by Bessel 

 was 70'68 years; its return was therefore ex- 

 pected in 1882 or 1883. Recently, however, 

 Professors Schulhof and Bossert have redis- 

 cussed the observations of 1812, including a 

 series by Banplain at Marseilles, which they 

 discovered in the original, and which were not 

 used by Bessel. The resulting period is 73 '18 

 years, and the most probable time of the next 

 return, September, 1884. 



