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Micrometrical Measures of Double and Multiple Stars in the Southern

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Micrometrical Measures of Double and Multiple Stars in the Southern ASTRONOMISCHE NACHRICHTEN. N2 3495-96. Band 146. 15-16. Micrometrical Measures af Double and Multiple Stars in the Southern Hemisphere made with the 61 cm Refractor of the Lowell Observatory. By T.r. r.See. In the course of a survey of the southern heavens lournal, which contains a description of the instruments of for the discovery and measurement of new double stars and ,he Observatory (the only account of the kind yet published) ; nebulae entered upon at Flagstaff 1896 August I, I have .he reader of this catalogue is referred to that source for swept over the greater part of the zone between -20° and nformation relative to the equipment and method of ob- -45O, besides the region included between -45" and -659 ;ervation. and the hours of right ascension 4 and 16, studied at In the accompanying catalogue the places of the stars Mexico. It is estimated that in this work we have examined ire referred to 1900.0. carefulky not less than IOOOOO stars brighter than I oth magni- tude. On reducing our results it is found that we have The following abbreviations are used : measured IOOO+ double and multiple stars; of which 500 Cord. GC. = Argentine General Catalogue Gould are new, while the remaining soot stars have been noticed Cord. ZC. = Argentine Zone Catalogue ] by previous observers. The systems discovered by former Cord. DM. = Cordoba Durchmusterung, l'home observers have sometimes been measured by them; but in AOe, - Argelander- Oeltzen the state of neglect until recently characteristic of southern SD. = Southern Durchmusterung, Schonfeld. stellar astronomy, it was often thought sufficient to note the duplicity of stars without even estimating the coordinates or On Double star observers : the magnitudes of the components. In some cases con- siderable lists of stars have been published as double with- R = Rlimker out any data which could be made the basis of future in- A - Dunlop vestigation. It is needless to point out that the observers h = Sir John Herschel who have pursued this unfortunate method of merely noting Hh = Sir William Herschel's work, as edited by the duplicity of stars without measuring them have missed Sir John a rare opportunity of contributing something of real value Jacob = Capt. W. S. Jacob Syd, = First Sydney Catalogue to the literature of double star astronomy. In view of the Russell fact that accurate measurement is the sole aim of double Syd, = Second Sydney Catalogue ] star observation, it seems clear that measurement is the only Sellors = R. P. Sellors contribution which should be recognized in adjudging the Innes = R. T. A. Innes right of discovery to observers. Yet as the stellar astronomy Ho = Hough of the southern hemisphere has hitherto rested in a state Harvard = Harvard observers, etc. of great confusion, and some observers have been unable to measure the systems they have discovered, I have thought Measures which have been made by my assistants, it proper in every case to credit the stars seen by previous Messrs. W. A. CogshZl and S. L. Boothroyd, are indicated observers to those by whom duplicity was first noticed, even by the names; in case more than one observer has taken though the first measurer had made the only contribution part in the work all the names are written to prevent con- to our knowledge of any real value. Accordingly in our fusion. In addition to the acknowledgement of their services survey all those stars noticed as double by previous ob- made elsewhere I must here bear witness to their patience, servers have been classed as >known double starsc. The zeal and interest in perfecting the work embodied in this following catalogue contains the measures of these systems catalogue. To those who are familiar with double star work made at the Lowell Observatory during the past year and with a great telescope, we need not point out the energy and four months. In many instances our measures are the first the skill required in the measurement, identification and re- that have ever been made, and on that account a great duction of a catalogue of this extent; accordingly, in the part of the accompanying results possess a degree of interest achievement of the results now presented to the public, it equal to that of the first measures of new double stars. will be understood that they have borne a great and in- Our discoveries at Flagstaff and at Mexico have been deed a distinguished part, which I acknowledge with lasting embodied in a catalogue communicated to the Astronomical gratitude. 15 227 3495 228 Micrometxjcal Yeaaures of Double and lldultiple Stars in the Southern Hemisphere. ,9 391 = x1 Sculptoris. h 3367. Cord. ZC. oh570. 0. Stone. Cord. GC. 784-3. Cord. GC. 56. a = oh 22m38?9, d = -32" 30'38Y7 a = Oh47"17!5, d = -23'9' 1515 a = Oh4"15?0, d= -28'32'3718 8.9, bl. white ; 9.2, bl. white. AB. 6.4, yellow; 6.4, yellow. 1896.75 5 7.4, yellow; 8, yellow, I 896.7 58 2 7 105 '135 .758 1 273.2 1 1.20 ,829 275.2 1.28 - 1896.769 i 176.9 I 5.44 1897.736 I 267.6 I 2.25 1896.782 I 273.3 I 1.28 No other measures since Herschel; motion uncertain. AC ; C I I, bluish. 1897.736 197.4 35.76 h 3377. Cord. GC. 472-3. 1897.657 I 93.0 I 1.17 Unchanged. No appreciable motion, unless in- a = oh 28m38t~,d = -26'38'3518 crease of distance. 5.9, orange; 10.5, purple. ,9 734 = G. 88 Ceti. 1897.736 I 9.00 Cord. GC. 791. ,9 393 = G. 31 Ceti. .736 1 :::: I 19.21 a = 0~47~46?0,d = -24'33'2!'5 Cord. GC. 205. 1897.736 1 56.4 I 19.10 6, or. yellow; 10, purple. a = Oh 13m13!0, 6 = -21'41'39)10 7.5, yellow; 8, yellow. h 3375 = G. 78 Sculptoris. 1897.627 345.6 11.25 .627 345.8 11.24 1897.711 18'f ol3f Cord. GC. 478. 1 I 1897.627 345.7 11.24 a = oh 28"50?0, d = -35" 32'8:7 I 1 Excellent estimates, not separated. No change. Perhaps a very slow direct motion, 7.3, yellow ; 9.1, bl. purple. with diminution of distance. 1896.733 166.5 6.05 B 233. AOe, 505- 1877.87 602 016f In Howe .788 I 165.1 I 6.01 a = oh 5om8?3, d = - 17" 59' 7:8 .788 j 164.6 6.03 h 1957. Cord. GC. 269. 7.5, yellow ; 8.8, bl. yellow. 1896.770 1 165.4 I 6.03 a = oh 16"48!8, d = -223'33'3218 No change. 1.52 7, yellow; 9.8, purple. 1897.627 22.4 6.37 1897.753 I 90.0 1 1-46 .627 I 22.8 I 6.11 Nice close system, unchanged. 1897.627 I 22.6 1 6.24 Fixed. h 2004 = G. 97 Ceti. Cord. GC. 881-0. Cord. dpl. I. Cord. ZC. oh489. a = 0"52"41!4, d= -19'32'22y3 a = oh 19"41?8, d = -33'53'28:f 6.5, yellow; 9.7, purple. 8.7, yellow; 9.4, bluish. 1897.799 1896.755 I 123.6 2.02 .799 1 :;zI ::;; .788 1 115.9 2.64 1897.799 I 239.2 I 3.88 .788 1 117.1 2.92 Very slight retrograde motion. 7896.777 I 118.9 I 2.53 I 897.627 278.0 A nice system; no other measures. 1 0. Stone = 8 735 = G. 98 Sculptoris. -627 279.3 h 1964 = G. 39 Ceti. Cord. GC. 987. Cord. GC. 352. a = Oh59"49t7, d = -34'4'614 n == oh 2 lrn 18!9, d = - 190 14' 49~2 6.5, yellow; 12.5, bl. purple. 7.8, yellow ; I 1.2, purple. 1896.703 219.8 8.04 1897.711 113.6 7.39 .788 1 219.1 1 8.52 .7II 1 114.6 I 7.23 .788 219.2 8.54 1897.711 1 114.1 1 7.31 1896.760 I 219.4 I 8.37 Probably fixed. No change. 229 3495 230 @ 1229. Cord. GC. 1244. h 3447 = z Sculptoris. h 3506 = a Fornacis. a = 1~14~41f6,6 = -35'1'318 Cord. GC. 1547. Cord. GC. 2693- 2. 8.3, yellow; 8.6, yellow. a = ih3~m3~?z,d = -30'25'9!'9 a = 2hagm27f9, 6 = -28°40'~7?4 6.3, yellow ; 8.7, bl. purple. 5.2, yellow ; 8.1, bl. yellow. 1896.793 28508 0!%9 .843 I 295.0 1 1.02 1896.785 9202 2!'18 1897.731 24304 I 1?13 .843 I 293.0 I 0.98 343 91.6 1.97 .731 1 243.1 1 11.09 1896.825 I 291.3 I 0.96 .844 1 94.0 1 1.88 1897.731 I 243.2 1 11.11 1896.817 92.6 2.01 1896.843 291.6 1.12 Cogshall I I No change in 60 years. Slow direct motion of 18' since Unchanged since I 89 I. 1835. h 3524. SD. -200506. h 2043 = G. 133 Ceti. h 3456. Cord. DM. -220578. a = 2h38m2~?8,6 = -20~43'4710 Cord. GC. 1299-1300. a = 1~39~22!7,6 = -21~55'54~5 6.9, yellow ; 9.5, purplish. 7.5, yellow; 10.2, purple. a = ih17~39?6, d = -19'36'815 '897.753 348.2 15.14 6.8, yellow; 8.8, purple.
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