Page:Encyclopædia Britannica, Ninth Edition, v. 2.djvu/877

of more than 69 in latitude. For when Pallas is at her greatest heliocentric latitude, and near opposition, her goocentric latitude exceeds 42. This is very different from Venus s range of less than 9 in geocentric latitude, which had been regarded as the maximum, and had led astrono mers to assign to the zodiac a breadth of 18. A zodiac to include the asteroids should be 90 in breadth, and would

cover -j^ths of the whole heavens.

Even more remarkable, however, was the discovery of two planets having nearly the same mean distance from the sun. The supposition that yet others might be found was naturally suggested ; indeed, Olbers was led to con jecture that Ceres and Pallas are but fragments of a larger planet formerly circulating at the same distance, and shattered by some tremendous internal convulsion ; and he proposed that search should be made where the paths of these planets nearly intersect. For if his theory were true, this must be the region where the explosion took place, and the fragments must continue to pass through that region.

While Harding of Lilienthal was charting the stars near the paths of Ceres and Pallas in the region thus indicated, he determined, on September 2,1804, the position of a small star in Pisces, near 93 and 98 of Bode s cata logue. On September 4 the star was no longer in the same position. It was found to be a planet (to which the name Juno was given) travelling at a mean distance of 2 6 7 (considerably less than that deduced for Ceres and Pallas), in an orbit having eccentricity 257, and inclina tion 13 1 . The effect of this great eccentricity is remark able, as may be thus indicated : supposing the apsides of the orbit to correspond to the planet s solstices, then the summer of one hemisphere is only half as long as the winter of that hemisphere, or as the summer of the other.

Next Olbers, pursuing the same method, discovered Vesta, moving in an orbit having mean distance 2 373 (far lesa even than Juno s), eccentricity OS98, and inclination r 7i .

A long interval then elapsed without the discovery of coveries. any new members of this remarkable family. It was not until December 8, 1845, that the fifth was recognised. On that night M. Hencke, an amateur astronomer of Driessen, discovered the body since named Astraea. He communicated his discovery to Encke and Schumacher, who confirmed it by observations made with more powerful telescopes. M. Hencke also discovered the sixth planet, on July 1, 1847. Since that time not a year has passed without the discovery of one or more minor planets ; and in some years as many as ten or twelve have been added, At present (April 1875), the total number known amounts to 143, as shown in the following table, which gives also the names of the discoverers, as well as the date and place of discovery. It is to be observed that Melete, numbered 56, was mistaken for 41 till January 1859.

No. Name. Date of Discovery. Discoverer. Place of Discovery. 1 Ceres 1801, January 1 Piazzi Palermo 2 Pallas 1802, March 28 Olbers Bremen 3 Juno 1804, September 1 Harding Lilienthal 4 Vesta 1807, March 29 Olbers Bremen 6 Astraea 1845, Decembers Hencke Driessen 6 Hebo 1847, July 1 Hencko Driessen 7 Iris August 13 Hind London 8 Flora October 18 Hind London 9 Metis 1848, April 25 Graham Markreo 10 Ilyguia 1849, April 12 I)c Gasparis Naples 11 Parthenope 1860, May 11 De Gasparis Naples 12 Victoria September 13 Hind London 13 Egeria November 2 De Gasparis Naples 14 Irene 1851, May 19 Hind London 15 Eunomia July 29 De Gasparis Naples 16 Psyche 1852, March 17 De Gasparis Niples 17 Thetis April 17 Luther Bilk 18 Melpomene June 24 Hind London 19 Fortuna August 22 Hind London 20 Massilia September 19 De Gasparis Naples LI Lutetia .November 15 Goldschmidt Paris No. Name. Date of Discovery. Discoverer. ; Place of Discovery. 22 Calliope 1852,Novemberl6 Hind 1 London 23 Thalia December 15 Hind London 24 * Themis 1853, April 6 De Gaspans Naples 2.5 Phocca Aprils Chacornac Marseilles 26 Proserpina May 6 Luther Bilk 27 Euterpe November 8 Hind London 28 Bellona 1854, March 1 Luther Bilk 29 Amphitrite March 1 Marth London 30 Urania July 22 Hind London 31 Euphrosyne September 1 Ferguson Washington 32 Pomona October 26 Goldschmidt Paris 33 Polvhymnia October 23 Chacornac Paris 34 Circe 1355, April 6 Chacoruac Paris 35 Leucothea April 19 Luther Bilk 36 Atalanta October 5 Goldschmidt Paris 37 Fides October 5 Luther Bilk " 8 Leda 1856, January 12 Chacornac Paris 39 Lsetitia February 8 Chacornac Paris 40 Harmonia March 31 Goldschmidt Paris 41 Daphne May 22 Goldschinidt Paris 42 Isis Mav 23 Pogson Oxford 43 Ariadne 1857, April 15 Pogson Oxford 44 Nysa May 27 Goldsehmldt Paris 45 Eugenia June 28 Goldschmidt Paris 46 Hestia August 16 Pogson Oxford 47 Aglaia September 16 Luther Bilk 48 Doris September 19 Goldschmidt Paris 49 Pales September 19! Goldschmidt Paris 50 Virginia October 4 Ferguson Washington 61 Nemausa 1858, January 22 Laurent Nismes 52 Europa February 6 Goluschmidt Paris 53 Calypso April 4 Luther Bilk 54 Alexandra September 10 Goldschmidt Paris 55 Pandora September 10 Searle Albany, U.S. 56 Melete 1857. September 9 Goldschmidt Paris 57 Mnemosyne 1859, September 22 Luther bilk 58 Concordia I860, March 24 Luther Bilk 59 Olympia Septembers Chacornac Paris 60 Echo September 1 5 Ferguson Washington 61 Danae September 19 Goldschmidt Chatillon-Eous-Bagneux 62 Erato October 10 Forster Berlin 63 Ausonia 1861, February 10 De Gasparis Naples 64 Angelina March 4 Tempel Marseilles 65 Cybele March 8 Tempel Marseilles 66 Maia April 9 Tuttle Cambridge, U.S. 67 Asia April 17 Pogson Madras 68 Leto April 29 Luther Bilk 69 Hesperia April 29 Schiaparelli Milan 70 Panopea May 5 Goldschmidt Fontenay-aux-Uoscs 71 Niobe August 13 Luther Bilk 72 Feronia May 29 Peters Clinton, U.S. 73 Clytie 1862, April 7 Tuttle Cambridge, U.S. 74 Galatea August 29 Tempel Marseilles 75 Eurydico Sept ember 22 Peters Clinton, U.S. 76 Freia October 21 d Arrest Copenhagen 77 Frigga November 12 Peters Clinton, U.S. 78 Diana 1863, March 15 Luther Bilk 79 Kurynome September 14 Watson Ann Arbor, U.S. 80 Sappho 1864, May 3 Pogson Madras 81 Terpsichore September 30 Tempel Marseilles 82 Alcmene November 27 Luther Bilk 83 Beatrix 1865, April 26 De Gasparis Naples 84 Clio August 25 Luther Bilk 85 lo September 19 Peters Clinton, U.S. 86 Semele 1866, January 6 Tietjen Berlin 87 Svlvia May 16 Pogson Madras 88 Thisbe June 15 Peters Clinton, U.S. 89 Julia August 6 Ste"phan Marseilles 90 Antiope October 1 Luther Bilk 91 jtgiua November 4 Ste"phan Marseilles 92 Undina 1867, July 7 Peters Clinton, U.S. 93 Minerva August 24 Watson Ann Arbor, U.S. 94 Aurora September 26 Watson Ann Arbor, U.S. 95 Arethusa November 23 Luther Bilk 96 1868, February 17 Coggia Marseilles 97 Clotho February 17 Tempel Marseilles 93 lanthe April 18 Peters Clinton, US. 99 Dike May 29 Borelly Marseilles 100 Hecate July 11 Watson Ann Arbor, U.S. 101 Helena August 16 Watson Ann Arbor, U.S. 102 Miriam August 22 Peters Clinton, U.S. 103 Hera September 7 Watson Ann Arbor, U.S. 104 10,5 106 Clymene Artemis Dione September 13 Sept ember 16 October 10 Watson Watson Watson Ann Arbor, U.S. Ann Arbor, US. Ann Arbor, U.S. 107 Camilla November 17 Pogson Madias 108 Hecuba 1869, April 2 Luther Bilk 109 Felicitas October 9 Peters Clinton, U.S. 110 Lydia 1870, April 19 Borelly Marseilles 111 Ate August 14 Peters Clinton, U.S. 112 Iphigenia September 19 Peters Clinton, U.S. 113 Amalthca 1871, March 12 Luther Bilk 114 116 Cassandra Thyra July 24 August 6 Peters Watson Clinton, U.S. Ann Arbor, U.S 116 Sirona September 8 Peters Clinton U.S. 117 Lorn i a September 12 Borelly Marseilles 118 Peitho 1872, March 15 Luther Bilk 119 Althxa April 3 Watson Ann Arbor, U S. 120 121 Lachesis Hermione April 10 May 13 Borelly Watson Marseilles Ann Arbor, U.S. 122 Gerda Julv 31 Peters Clinton, U.S. 123 Brunhilda July 31 Peters Clinton, U.S 124 A Ices! is August 23 Peters Clinton, U.S. 125 Liberatrix September 11 Prosper Henry . Paris 126 Vclleda November 5 Paul Henry Paris 127 Johanna November 5 Prosper Ueary I M-, is 128 Nemesis November 26 Watson Ann Ajrtor, U.S 1 No. Name. Date of Discovery. Discoverer. Place of Discovery, 129 Antigone 1873, February 5 Peters Clinton, U.S. 130 Electra February 17 Peters J Clinton, U.S. 131 Vala May 26 Peters Clinton, U.S. 132 jEthra June 13 Watson Ann Arbor, U.S. 133 Gyrene August 16 Watson Ann Arbor, U.S. 134 Sophrosyne September 27 Luther Bilk 135 Ilertha 1874, February 18 Peters Clinton, U.S. 13(! Austria March 18 Palisa Pola 137 Melibcea April 21 Palisa Pola 138 Tolosa May 19 Perrotin Toulouse 139 October 10 Watson Peking (Transit Exped.. 140 Siwa October 13 Palisa Pola 141 1875, January 13 Paul Henry Paris 142 January 28 Palisa Pola 143 ... February 23 Palisa

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