Case Stephen
Program for the History and Philosophy of Science, University of Notre Dame, 453 Geddes Hall, Notre Dame, IN 46556, USA.
Endeavour. 2014 Mar;38(1):27-34. doi: 10.1016/j.endeavour.2013.12.001. Epub 2014 Feb 6.
Previous research on the origins of double star astronomy in the early nineteenth century emphasized the role mathematical methods and instrumentation played in motivating early observations of these objects. The work of the British astronomer John Herschel, however, shows that questions regarding the physical nature of double stars were also important. In particular, an analysis of John Herschel's early work on double stars illustrates the way in which speculations regarding these objects were shaped by assumptions of the properties of stars themselves. For Herschel, a major consideration in double star astronomy was distinguishing between types of double stars. Optical doubles were useful in determining parallax while binary doubles were not. In practice, classification of a specific double star pair into one of these categories was based on the assumption that stars were of approximately the same luminosity and thus differences in relative brightness between stars were caused by difference in distances. Such assumptions, though ultimately abandoned, would lead Herschel in the 1830s to advance the possibility that the dim companion stars in certain double star pairs were not stars at all but in fact planets.
先前对19世纪早期双星天文学起源的研究强调了数学方法和仪器在推动对这些天体的早期观测中所起的作用。然而，英国天文学家约翰·赫歇尔的工作表明，关于双星物理性质的问题也很重要。特别是，对约翰·赫歇尔早期双星研究的分析表明，关于这些天体的推测是如何受到恒星本身性质假设的影响的。对赫歇尔来说，双星天文学中的一个主要考虑因素是区分双星的类型。光学双星在确定视差方面很有用，而双星则不然。在实践中，将特定的双星对分类为这些类别之一是基于这样的假设，即恒星的光度大致相同，因此恒星之间相对亮度的差异是由距离差异造成的。这样的假设虽然最终被放弃了，但在19世纪30年代会促使赫歇尔提出这样一种可能性，即某些双星对中较暗的伴星根本不是恒星，而实际上是行星。
