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168 ASTRONOMY: NAIL, ET AL. PROC. N. A.- S. 22 "Nebulosities of the Small Magellanic Cloud," a communication presented at the Boulder, Colo., meeting of the American Astronomical Society, August, 1953; see also Paper IX in this series, these PROCEEDINGS, 39, 1168-1176 (1953). MAGELLANIC CLOUDS, IX. THE NEBULOSITIES OF THE SMIALL CLOUD By VIRGINIA MCKIBBEN NAIL, CHARLES A. WHITNEY, AND CAMPBELL M. WADE HARVARD COLLEGE OBSERVATORY Communicated by Harlow Shapley, October 12, 1953 The presence of hydrogen-emission nebulosity in the Small Magellanic Cloud is strikingly illustrated on several plates made with a 3-inch f/1.5 Zeiss-Sonnar camera, exposed from four to six hours. Red sensitive (103 a-E) Eastman plates were used with a red glass filter (Corning 2403) in conjunction with an H-alpha interference filter. This camera, kindly lent to Harvard's Boyden Station by Mr. Richard S. Perkin, has been effective in the study of emission details in the Milky Way. The scale is too small, however, to show the detailed structure in the Cloud's nebulosity. From an examination of a 90-minute red (103 a-E) plate and a 60-minute blue (103 a-O) plate, both made with the Baker-Schmidt telescope, we find that the nebulosities have the characteristics of Galactic H(II) regions. Table 1 is a catalog of the emission nebulosities in the Small Magellanic Cloud. In the first column is the new assigned number; the second, the number published in the NGC or IC catalogues or in Harvard Circulars 275 and 276.1 The early work of Shapley and Wilson was based on long- exposure blue plates and is affected by the color characteristics of the Bruce telescope. Not all the objects described by them as nebulous could be found; a few were identified as galaxies and a few as open clusters, but 125 of the 152 objects in table 1 were in the Shapley-Wilson lists. We have in- cluded in this catalogue only those objects which on the red plate show nebulosity or which have definite non-stellar images. The objects found during the course of this investigation have no numbers in the second column. The third column of table 1 gives the position in X and Y coordinates, as described in Harvard Annals, 60, No. 4 (1907). The fourth gives the di- mensions in parsecs with the Cloud's distance taken as 50 kpc. In the fifth is a short description, and the last column gives the type in the Bok- Wade classification. The criteria are structure, or shape, and surface brightness. The apparent and linear sizes of the nebulae and the spectral type and luminosity of the exciting star do not enter into the classification. A summary of the Bok-Wade system follows (p. 1171) .2 Downloaded by guest on September 25, 2021 VOL. 39, 1953 ASTRONOMY: NAIL, ET AL. 1169 TABLE 1 CATALOG OF EMISSION NERULOSITIES IN THE SMALL MAGELLANIC CLOUD SERIAL CATALOG -POSITION- DIMENSIONS NUMBER NUMBER X Y IN PARSECS DESCRIPTIVE REMARKS T'"YPE 1 91 7054" 5669" Faint wisp, nebulous star V 2 93 7526 6311 2 X 6 Irregular nebula near star II 3 N 176 7944 8046 10 X 10 Nebula between two stars II 4 ... 8699 5427 Nebulous star v 5 N 220 9186 7284 6 X 6 Two or more stars involved in nebu- II losity 6 N 222 9240 7351 4 X 4 Irregular nebulosity, central con- II densation 7 N 231 9234 7471 10 X 5 Irregular nebulosity two condensa- II tions 8 5 9736 6103 2 X 3 Two stars involved II 9 6 9750 8142 2 X 2 Nebulosity around group of three 1I stars 10 7 9774 8164 2 X 1 Nebula between two stars II 11 9906 9108 8.5 X 4 Very faint patch II 12 105 9912 8808 . .. Nebulous star v 13 N 241 9973 7194 4 X 4 Several stars involved in nebulosity II 14 N 242 9996 7174 1 X 1 Nebulosity between two stars II 15 107 10281 8170 4 X 4 Nebulosity around four stars II 16 ... 10339 7804 Bright nebulous star v 17 8 10373 8008 4 X 2 Nebulous cluster II 18 N 249 10430 8525 30 X 25 Nebulosity with condensations II 19 N 248 10440 7444 8 X 15 Nebula around and between stars II 20 9 10513 6261 Nebulous star v 21 ... 10529 8423 17 X 3 Very faint nebulous wisps II 22 10 10546 10308 6 X 8 Irregular nebulosity II 23 N 256 10596 6982 6 X 6 Nebulous cluster II 24 i11 10604 12214 3 X 3 Small nebula, three condensations v 25 N 261 10703 8455 16 X 20 One or two stars involved in nebu- 11 losity 26 115 11044 8331 80 X 80 Nebulous patch, limits vague II 27 15 11067 8026 4 X 4 Crescent-shaped nebulosity II 28 N 267 11123 7841 30 X 30 Irregular nebulous patch II 29 117 11136 7073 4 X 4 Small, irregular patches v 30 17 11139 7974 8 X 8 Circular nebula with a central star III 31 N 269 11228 6921 4 X 4 Part of circle, one bright star IV: 32 119 11238 5717 3 X 4 Two stars in faint nebulosity II 33 120 11251 7730 8 X 8 Irregular nebulous patch II 34 122 11334 8375 4 X 5 Arc of circle, central star IV 35 ... 11367 8329 Nebulous star v 36 ... 11385 8438 Nebulous star v 37 18 11388 7534 . Nebulous star v 38 123 11430 7950 8 X 12 Nebulous patch II 39 125 11452 7492 Nebulous star v 40 126 11464 9418 . Elongated nebulous star v 41 127 11498 9528 3 X 3 Small nebulous group (?) stars v 42 ... 11545 8228 ... Nebulous star 43 20 11550 9104 1 X 2.5 Nebula (?) between two stars 44 ... 11597 10544 Nebulous star v 45 ... 11614 10522 ... Nebulous star v 46 128 11632 7921 Nebulous star Vv 47 11636 10504 8 X 2 Crescent shaped, uniformly bright II nebulosity 48 129 11642 7633 4 X 8 Faint crescent-shaped nebula near If two stars 49 130 11702 9294 45 X 50 Nebulous patch II 50 131 11730 7755 Nebulous star v 51 132 11734 7446 3 X 3 Nebulous mass, uniformly brighter in middle Downloaded by guest on September 25, 2021 1170 ASTRONOMY: NAIL, ET AL. PROC. N. A. S. SERIAL CATALOG .-POSITION-- DIMENSIONS NUMBER NUMBER X Y IN PARSECS DESCRIPTIVE REMARKS TYPE 52 24 11740" 8118" 4 X 4 Faint nebulous patch II .53 133 11762 8934 2 X 2 Nebulous patches and stars II 54 134 11764 9000 4 X 4 Round nebula, bright star off center I 55 27 11826 9846 4 X 4 Nebulous (?) group II 56 28 11859 8126 3 X 4 Uniformly bright nebulosity II 57 11889 9536 . Nebulous star V 58 135 11957 6721 Irregular, nebulous star V 59 136 12068 8037 4 X 7 Nebulous patch with condensations II 60 32 12100 9037 1 X 3 Group of nebulous stars (?) V 61 137 12106 7131 2.5 X 8 Three stars in wisp 11 62 33 12152 11955 Nebulous star V 63 34 12157 10564 Nebulous stars V 64 12243 10020 Bright nebulous star V 65 140 12265 8684 2.5 X 6 Nebulous wisps II 66 141 12310 9140 Nebulous star V 67 142 12321 9602 Nebulous star (?), wisp (?) V 68 37 12322 8938 2.5 X 2.5 Nebula plus three or four stars II 69 143 12365 7374 2 X 6 Several stars involved in nebulosity II 70 144 12382 9234 30 X 40 Faint extended nebulosity II 71 40 12399 10196 4 X 4 Nebulous patch and stars II 72 42 12446 14668 4 X 6 Three stars in nebulous wisp II 73 43 12461 9713 3 X 3 Nebulous patch, bright stars II 74 N 299 12471 11777 6 X 6 Nebulous cluster II 75 146 12518 10074 3 X 3 Round nebula, central star III 76 147 12569 10114 Nebulous star V 77 149 12631 10761 1 X 2.5 Nebulous star involved in faint nebu- V losity 78 N 306 12704 11623 6 X 6 Nebulous patch and stars II 79 150 12730 9950 5 X 5 Round nebula, central star III 80 151 12734 7826 . Nebulous star V 81 153 12851 10807 3 X 4 Nebulous patch and stars II 82 45 12877 12083 3.5 X 5.5 Irregular nebula with condensations II 83 47 12931 7356 . Nebulous stars V 84 155 12981 7799 2.5 X 2.5 Faint regular patch of nebulosity II near star 85 156 13007 7035 2 X 2 Fan-shaped nebulosity II 86 13059 12803 Nebulous star V 87 157 13065 12559 Nebulous star V 88 160 13257 11415 Nebulous star V 89 55 13600 11535 4 X 4 Bright, round nebula with three stars II in center 90 165 13655 7326 34 X 34 Very faint patch II 91 ... 13656 9089 Nebulous star V 92 167 13742 10922 1 X 2.5 Nebulous star, faint wisp V 93 ... 13763 10101 30 X 35 Faint extended patch II 94 168 13775 7894 2.5 X 3 Faint nebulous patch II 95 58 13796 12484 Nebulous star V 96 13800 7106 . Nebulous star V 97 169 13801 10149 5 X 5 Circular nebula with central star in III nebulosity no. 93 98 59 13829 11408 Nebulous star V 99 60 13839 10081 6 X 5 Nebulous group, three nebulous stars II 100 61 13921 10908 Nebulous star V 101 N 346 14055 11874 80 X 100 Very bright nebulous group I 102 171 14060 10286 2 X 2 Nebulous (?) group II 103 ..
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