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Beyond the planets: early nineteenth-century studies of double stars
Published online by Cambridge University Press: 05 January 2009
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In 1837 the German-born astronomer F. G. W. Struve published his famous catalogue of double stars. For Struve this was the culmination of 12 years' detailed observation of a class of celestial objects lying exclusively beyond the solar system; for historians of astronomy it poses the problem of explaining why the study of double stars became a significant part of astronomical endeavour, as it did, during the 1820s and 1830s. For, although Struve's interest was extreme, it was shared to a lesser extent by several eminent contemporaries, including John Herschel, Friedrich Bessel, Johann Encke, James South and Félix Savary. Their combined efforts represented an important transition in astronomy: for the first time one of the emphases of the subject moved beyond the solar system to the so-called fixed stars. The question of the emergence of interest in double stars is of historical significance, therefore, as it is related to the problem of the origins of ‘stellar astronomy’. This essay is thus intended to offer an explanation of astronomers' interest in double stars, and to tackle the related question of whether this transition constituted a major break in the history of astronomy. Furthermore it is proposed that answers to these problems may be found by considering the practice of astronomy dominant during the first half of the nineteenth century. Astronomers in this period were overwhelmingly concerned with a refined form of positional astronomy. The problems they chose to solve were by and large related to the difficulties of the accurate reduction of observational data, and the compilation of reliable tables and star charts, which were then used as a background against which the motions of solar system objects were plotted. By assessing individuals' studies of double stars within this context it can be seen firstly that such studies were no more or less than specific examples of a general case, and secondly that the stars themselves were not usually of intrinsic interest. In general it was the positions of the stars on the
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- The British Journal for the History of Science , Volume 17 , Issue 3 , November 1984 , pp. 295 - 309
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- Copyright © British Society for the History of Science 1984
References
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20 Ibid., 161: ‘Gelingt es uns, die jährliche Parallaxe dieses Sternenpaars zu beobachten… so würden wir daraus die summe ihrer Massen berechnen können.’
21 Idem., ‘Untersuchungen des Theils des planetarischen Störungen, welche aus der Bewegung des Sonne entsteht’, Abhandlungen der Berliner Akademie der Wissenschaften (Mathematische Classe) 1824, Berlin, 1824, 1–31Google Scholar; and ‘Bestimmung der Entfernung des 61 des Sterns des Schwans’, Astronomische Nachrichten, 1839, 16, 65–85.Google Scholar
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33 Amici's work on doubles was known in Britain only via the accounts of it published by von Zach in his periodical Correspondence Astronomique, published in Genoa.
34 South, J., ‘Observations on the best mode of examining the double or compound stars’, Memoirs of the Astronomical Society of London, 1822, 1, 109–14, 109.Google Scholar Paper read 5 May 1820.
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38 See under ‘Doppelsterne’ in the indexes of the following volumes of correspondence: Gauss-Olbers, edited by C. Schilling, in Gauss, C. F., Werke: Briefwechsel mit H. W. M. Olbers, Berlin 1900Google Scholar; Gauss-Bessel, edited by R. Englemann, in idem., Werke: Briefwechsel mit F. W. Bessel, Leipzig, 1880Google Scholar; Gauss-Schumacher, edited by C. A. F. Peters, in idem., Werke: Briefwechsel mit H. C. Schumacher, St. Petersburg, 1860–1863.Google Scholar See also Briefwechsel zwischen Olbers und Bessel, edited by Erman, A., Leipzig, 1852, 2, 311–2, 316–23.Google Scholar
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43 Encke, J. F., ‘Über die Berechnung der Bahnen der Doppelsterne’, Berliner astronomisches Jahrbuch für 1832, Berlin, 1830, 253–304.Google Scholar
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45 The catalogue was published in stages in the pages of the Memoirs of the Royal Astronomical Society: 1826, 2, 459–97Google Scholar; 1829, 3, 47–63, 177–213; 1831, 4, 331–96; 1833, 6, 1–73; 1836, 9, 193–204.
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50 A number of other characters showed interest also, including Mädler, who studied the orbits of binaries, Dawes, an English astronomer who ran a private observatory in Ormskirk and made many observations of doubles, Dunlop, who compiled a catalogue of doubles visible from his observatory in New South Wales, and von Zach who published a number of letters about doubles in his Correspondence astronomique.
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52 Letter from Olbers to Bessel, 21 October 1821, printed in Olbers-Bessel correspondence, ref. 38, 2, 212: ‘Sie, lieber Bessel, und unser Gauss, machen eine förmliche Revolution, und eine wirkliche Epoche in der beobachtenden Astronomie.’
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