Page:1902 Encyclopædia Britannica - Volume 27 - CHI-ELD.pdf/190

 COMETS

162 Period in years. 3-303

unexpected comets were discovered (four on photographic Remarks. plates, the others after search with visual telescopes) Regularly returning since 1786, besides a number of expected (periodic) comets. During Encke last observed in 1901. Its brightness in 1891 was about the same as in 1858. Sudden the years 1782 to 1841 eighty-seven comets of both changes of brilliancy were observed at some of its returns (1865 classes were observed, or 1-45 per year, while from 1842 and 1898 for example). Computers—Backlund, Ivanow. to 1897 there were 241 comets, or 4*30 per year. The 5-218 Last observed 1899. Com- difference in the average numbers probably represents Tempel (II) puter—Schulhoff. nothing more than the increased attention paid to cometary 5 "400 Last observed 1884. Barnard 5"456 Last observed 1879. See the discovery in late years. For example, ten comets were Brorsen remarks under Denning’s discovered during 1898, three of them being known comet below. 5"534 Last observed 1891. Com- periodic comets. In the year 1840 a gold medal was Tempel - L. Swift . founded by Christian VIII., king of Denmark, to be puter—Bossert. 5 "818 Lastobserved 1898. Computers given to discoverers of telescopic comets, but after his Winnecke Yon Haerdtl and Hillebrand. death the award was discontinued. The comet medal 5"863 Last observed 1894. It is the (bronze) of the Astronomical Society of the Pacific was De Yico - E. Swift comet 1844 I. (De Yico). founded by Hon. Joseph A. Donohoe in the year 1890, Computer—Chandler. and is presented to the discoverer of every unexpected 5"595 Last observed 1886. Brooks. 5"98 Observed in 1867, 1873, and comet on the report of a committee of the society. A Tempel (I.) 1879 ; subject to large per- list of the awards constitutes, therefore, a history of turbations by Jupiter 1879-85, and not since seen. Computer recent cometary discoveries. —Gautier. 6-226 Last observed 1892. ComBarnard List of Unexpected Comets discovered since 1st January puter—Coniel. 1890. 6-402 Last observed 1890. CornSpitaler puter—Spitaler. At Discovered by Discovered on 6-441 Discovered 1896. Computers— Perrine Geneva, N.Y. March 19, 1890 W. R. Brooks Ristenpart, Hadley. Marseilles, France July 18, 1890 Jerome Coggia Discovered 1896. 6-549 Giacobini Bristol, England July 23, 1890 W. F. Denning Discovered 1772; seen 1805, 6-6 Biela (I. and II.) Palermo, Italy Nov. 15, 1890 T. Zona 1826, and 1832. In 1846 Yienna, Austria Nov. 16, 1890 R. Spitaler it divided into two parts, which were widely separated at its reLick Observatory, Cal. March 29, 1891 E. E. Barnard turn of 1852. It has not since been observed. October 3, 1891 E. E. Barnard >> 6-622 Last observed 1893 (second reFinlay Rochester, N.Y. March 6, 1892 Lewis Swift turn). Computer—Schulhoff. Bristol, England March 18, 1892 W. F. Denning 6-691 Observed in 1851, 1857, 1870, D’Arrest Geneva, N.Y. August 28, 1892 W. R. Brooks 1877, 1890, 1897. ComLick Observatory, Cal.1 October 12, 1892 E. E. Barnard puter—Leveau. London, England 6, 1892 Edwin Holmes Nov. 6-821 Regularly returning; last obWolf Geneva, N.Y. Nov. 19, 1892 W. R. Brooks served 1898. Computer— Lick Observatory, Cal.2 April 16, 1893 J. M. Schaeberle Thraen. Geneva, N.Y. W. R. Brooks October 16, 1893 6-86 Last observed 1896. Its orbit Giacobini Bristol, England 26, 1894 W. F. Denning somewhat resembles that of March Paddington, N.S.W. 2, 1894 W. F. Gale April comet Faye. Computer— Lowe Observatory, Cal. 20, 1894 E. D. Swift Nov. Pokrowsky. August 20, 1895 Lewis Swift JJ >> 6-904 Last observed 1899 within its Holmes Lick ,, ,, Nov. 17, 1895 C. D. Perrine calculated place by 28 s. in Geneva, N.Y. 21, 1895 W. R. Brooks Nov. R.- A., 5' in Dec. Its calculated period required a correction of Feb. Lick Observatory, Cal. 15, 1896 C. D. Perrine 0 3 of a day only. This comet was, in 1892, subject to changes Lowe ,, . ,, April 13, 1896 Lewis Swift of brightness suggesting internal changes. The question arises Randolph, Ohio August 31, 1896 W. E. Sperra why so bright a comet was not earlier discovered. Its orbit is Nice, France 4, 1896 E. Giacobini Sept. more nearly circular than that of any other comet, and lies Lick Observatory, Cal. 2, 1896 C. D. Perrine wholly between the orbits of Mars and Jupiter, in the region of Nov. 8, 1896 C. D. Perrine Dec. asteroids therefore. Its spectrum shows only a trace of one bright October 16, 1897 C. D. Perrine line. Computer—Zwiers. March 20, 1898 C. D. Perrine 7-059 Last observed 1895. It is not June Swift 11, 1898 E. F. Coddington unlikely to be a return of June 14, 1898 C. D. Perrine Lexell’s comet of 1770. Nice, France 18, 1898 E. Giacobini June Brooks Last observed 1896. Its spec7-097 Lick Observatory, Cal. 13, 1898 C. D. Perrine Sept. trum was continuous. It Geneva, N.Y.4 5 October 20, 1898 W. R. Brooks was at first supposed to be a return of Lexell’s comet, but the reNew Haven, Conn. 14, 1898 F. L. Chase Nov. searches of Dr C. L. Poor make the identity unlikely. Lowe Observatory, Cal. 3, 1899 Lewis Swift Denning (II) . 7 "42 Lastobserved 1894. Its orbit March Nice, France E. Giacobini 29, 1899 Sept. lies within 0-16 of Jupiter’s orbit, and near that point crosses the orbit of Brorsen’s comet. The two comets were near the point of intersection in 1881 (though A few of the remarkable comets of the years 1888-1900 Jupiter was not then near) which may account for the disappear- are here briefly described. Comet 1888 I. exhibited ance of Brorsen’s comet since its return in 1879. peculiar variations in its head like those which distin7"566 Last observed 1896. Faye 8 "534 Last observed 1889. Com- guished the comets 1882 II. and 1884 I. Two (or Swift . puter—Coniel. according to one observer three) nuclei were enclosed in Denning (I.) 8 "867 Last observed 1881. a nebulous sheath, as in 1882 II. On 21st May, two 13'76 Last observed 1899. Com- months after perihelion passage, the head suddenly beTuttle. puter—Rahts. came about two stellar magnitudes brighter, and two jets 33T8 Last observed 1866. Tempel. 40-09 Last observed 1867. Stephan were ejected from it, both much brighter than the main 60-7 Last observed 1852. Westphal 1 71 48 Observed in 1812 and 1884. Pons-Brooks 2 This is the first comet discovered by photography. This comet was discovered on the photographs of theintotal 72 63 Observed 1815solar and 1887. Olbers. eclipse taken by the Lick Observatory eclipse expedition to Chile. 75 "7 Last observed 1846. De Yico 3 Discovered by photography. 76 "37 Regularly returning. The next Halley. 4 The orbit of this comet resembles that of Schaeberle’s comet of appearance is 1910. 1881. 5 In the course of the ten years 1890-99 thirty-seven Discovered by photography. Name.