In the domain of astronomy the object oriented paradigm of informatics needs to construct an ontology to be able to reason about concepts and to construct queries in a computerized knowledge system. The article presents approaches to ontology in philosophy, the natural sciences and informatics and shows their limits and reciprocity.

In the domain of astronomy the object oriented paradigm of informatics needs to construct an ontology to be able to reason about concepts and to construct queries in a computerized knowledge system. The article presents approaches to ontology in philosophy, the natural sciences and informatics and shows their limits and reciprocity.

This work inaugurates a critical inquiry into whether the ideas of Karl Popper, a philosopher of science, are used by astronomers and astrophysicists, a practicing community of scientists. It examines four basic components of Karl Popper's philosophy— falsification, prohibition, simplicity, and risk taking— and the extent that these themes become integrated into recent scientific literature on astronomy, astrophysics, cosmology, and stellar evolutionary theory. It concludes that the philosophy of science is highly relevant to the practice of astronomy, and (...) that Karl Popper plays a unique role in directing different communities of astronomers and cosmologists. (shrink)

Thomas Hornsby was a hard-working, scientifically ambitious and significant man of vision during the second half of the eighteenth century. He was a notable astronomical observer, founder of the Radcliffe Observatory at Oxford, a successful lecturer, a Commissioner of Longitude at a critical time, and editor of James Bradley's Astronomical Observations. This paper presents some long-neglected facts; in assembling scattered fragments into a coherent account, it raises new speculations.

We present the historical development of Nonlinear Dynamical Astronomy with emphasis on the “third integral” and its applications. The new era started with the use of computers, and of formal analytical developments in the spirit of Poincaré. Most dynamical systems were found to contain both ordered and chaotic orbits. The transition from order to chaos is discussed. Recent developments refer to the dynamical spectra, integrals of notion in self-consistent models, systems of 3 or more degrees of freedom, chaos in (...) relativity and cosmology, and chaos in quandum mechanics. (shrink)

The 2006 decision by the International Astronomical Union to strip Pluto of its status as a planet generated considerable uproar not only in scientific circles, but among the lay public as well. After all, how can a vote by 424 scientists in a conference room in Prague undermine what every well-educated second grader knows is a scientific fact? The Pluto controversy provides a new and fertile ground in which to revisit the traditional philosophical problems of natural kinds and scientific change. (...) Before engaging these philosophical problems, however, there are two misguided reactions to the Pluto controversy worth dispelling from the start. The first misguided reaction is that this sort of classificatory .. (shrink)

Observational astronomy is plagued with selection effects that must be taken into account when interpreting data from astronomical surveys. Because of the physical limitations of observing time and instrument sensitivity, datasets are rarely complete. However, determining specifically what is missing from any sample is not always straightforward. For example, there are always more faint objects (such as galaxies) than bright ones in any brightness-limited sample, but faint objects may not be of the same kind as bright ones. Assuming they (...) are can lead to mischaracterizing the population of objects near the boundary of what can be detected. Similarly, starting with nearby objects that can be well observed and assuming that objects much farther away (and sampled from a younger universe) are of the same kind can lead us astray. Demographic models of galaxy populations can be used as inputs to observing system simulations to create “mock” catalogues that can be used to characterize and account for multiple, interacting selection effects. The use of simulations for this purpose is common practice in astronomy, and blurs the line between observations and simulations; the observational data cannot be interpreted independent of the simulations. We will describe this methodology and argue that astrophysicists have developed effective ways to establish the reliability of simulation-dependent observational programs. The reliability depends on how well the physical and demographic properties of the simulated population can be constrained through independent observations. We also identify a new challenge raised by the use of simulations, which we call the “problem of uncomputed alternatives.” Sometimes the simulations themselves create unintended selection effects when the limits of what can be simulated lead astronomers to only consider a limited space of alternative proposals. (shrink)

This article charts the development of the modern astronomical observational system. I am interested most acutely in the digitization of this system in general, and in the introduction of adaptive optics in particular. I argue that these features have been critical in establishing the modern observatory as a factory for scientific data, rather than as a center of calculation in its own right. Throughout, the theoretical focus is on the nature of technological evolution in the observational system, understood as inextricably (...) bound up with both the system-internal drive to surpass the limits imposed upon the distributed cognition of the researcher and the boundary at which empirical objects resolve themselves into technical objects. In short, this article explores the historically constituted character of expert astronomical perception, arguing that it is impossible to understand without constant reference to its material substrate. (shrink)

In Hellenistic Astronomy: The Science in Its Contexts, renowned scholars address questions about what the ancient science of the heavens was and the numerous contexts in which it was pursued.

In his comprehensive survey of the work of William Herschel, published in the Annuaire du Bureau des Longitudes for 1842, Dominique Arago argued that the life of the great astronomer ‘had the rare privilege of forming an epoch in an extended branch of astronomy’. Arago also noted, however, that Herschel's ideas were often taken as ‘the conceptions of a madman’, even if they were subsequently accepted. This fact, commented Arago, ‘seems to me one that deserves to appear in the (...) history of science’. From the time Herschel published his first paper in the Philosophical transactions in 1781, he was subjected to the suggestion of lunacy. His patron and friend William Watson, told him that after his claims for the extraordinary power of his telescopes, ‘your prognosis that some would think you fit for Bedlam has been verified’. On learning of Herschel's supremely accurate new micrometer, the astronomer Alexander Aubert exclaimed to Herschel that ‘we would go to Bedlam together’: Aubert wrote to Herschel in January 1782 that he should ‘mind not a few jealous barking puppies: a little time will clear up the matter, and if it lays in my power you would not be sent to Bedlam alone, for I incline much to be of the party’. (shrink)

The significance of the plurality of the Copernican Revolution is the main thrust of this undergraduate text In this study of the Copernican Revolution, the ...

: We question the claim, common since Duhem, that sixteenth century astronomy, and especially the Wittenberg interpretation of Copernicus, was instrumentalistic rather than realistic. We identify a previously unrecognized Wittenberg astronomer, Edo Hildericus (Hilderich von Varel), who presents a detailed exposition of Copernicus's cosmology that is incompatible with instrumentalism. Quotations from other sixteenth century astronomers show that knowledge of the real configuration of the heavens was unattainable practically, rather than in principle. Astronomy was limited to quia demonstrations, although (...) demonstration propter quid remained the ideal. We suggest that Osiander's notorious preface to Copernicus expresses these sixteenth century commonplaces rather than twentieth century instrumentalism, and that neither `realism', nor `instrumentalism', in their modern meanings, apply to sixteenth century astronomy. (shrink)

Plato's comments on astronomy and the education of the guardians at Republic 528e ff have been hotly disputed, and have provoked much criticism from those who have interpreted them as a rejection or denigration of observational astronomy. Here I argue that the key to interpreting these comments lies in the relationship between the conception of enquiry that is implicit in the epistemological allegories, and the programme for the education of the guardians that Plato subsequently proposes. We have, I (...) suggest, been too eager to stress the similarities here, when recognition of the differences may supply us with the tools required for a better understanding of 528e ff, one that to a large extent disarms the anti-empirical critique. My discussion proceeds in three stages. Firstly, Plato takes great care to place his comments on astronomy in the context of the preceding epistemological allegories. Is there any evidence here, where Plato might be thought to discuss enquiry in general, that he rejected or denigrated observation? I argue that even if Plato advocated a 'Two Worlds' (TW) ontology, he still envisaged a dynamic process of enquiry, interrelating sensibles and intelligibles, the investigation of each being necessary but not sufficient to achieve the overall aim. Secondly, Plato appears to be deriving how we ought to go about educating the guardians from how we ought to conduct our enquiries. While the two are intimately related there are important differences, recognition of which turns the supposed rejection of observation into an affirmation of the need for an initial empirical approach. I contend that this makes good sense of the internal structure of 528e ff, and of its relations to other parts of the Republic. Thirdly, I discuss the Republic in relation to the evidence offered by later works on the question of astronomy and observation, and raise the question of whether Plato's views on the imperfection of the sensible world necessarily lead to the denigration of careful and prolonged empirical work. (shrink)

This volume represents the first which interfaces with astronomy as the fulcrum of the sciences. It gives full expression to the human passion for the skies. Advancing human civilization has unfolded and matured this passion into the comprehensive science of astronomy. Advancing science’s quest for the first principles of existence meets the ontopoietic generative logos of life, the focal point of the New Enlightenment. It presents numerous perspectives illustrating how the interplay between human beings and the celestial realm (...) has informed civilizational trends. Scholars and philosophers debate in physics and biology, the findings of which are opening a more inclusive, wider picture of the universe. The different models of the universal order and of life here presented, all aiming at the first principles of existence—accord with the phenomenology/ontopoiesis of life within the logos-prompted primogenital stream of becoming and action, which points to a future of progressing culture. (shrink)

This book provides the first presentation of the bilingual textual material that illustrates the transmission of Islamic astronomy to scientists of the Indian Sanskritic tradition. It includes editions of the chapter of the _Tadhkira_ in which the mid-thirteenth century Persian astronomer, Nasīr al-dīn al-ṭūsī discussed the new solutions that he devised to overcome certain technical problems in the lunar and planetary models of Ptolemaic astronomy and of the learned commentary composed by al-Birjandī in the early sixteenth century together (...) with the Sanskrit translation of both made by Nayanasukha at Jaipur in 1729. An English translation of the Arabic texts and a commentary discussing their technical meanings and the deviations from them in the Sanskrit version together with a glossary of the Arabic and Sanskrit technical vocabulary conclude the volume. (shrink)

Abraham ibn Ezra d'Espagne (m. 1167) fut l'un des plus importants savants ayant contribué à la transmission de la science arabe à l'Occident. Ses ouvrages en astrologie et en astronomie, rédigés en hébreu puis traduits en latin, étaient considéréd comme faisant autorité par de nombreux savants juifs et Chrétiens. Parmi les ouvrages qu'il a traduits de l'arabe en hébreu, certains sont perdus dans leur langue originale et ses propres ouvrages renferment certaines informations concernant des sources anciennes mal ou pas du (...) tout connues par ailleurs. Ibn Ezra semble être le premier a avoir consigne l'une des sept méthodes pour dresser les maisons astrologiques. Cette méthode avait par la suite été utilisée par Lévi ben Gershom (m. 1344) dans le Midi de la France. (shrink)

In this contribution, we explore a little-referenced effort of Rheticus in favor of the reception of the astronomy of his teacher Copernicus in the religious circle of his time. This appears in his "Treatise on Sacred Scripture and the Motion of the Earth", a document lost for centuries, and rediscovered by Hooykaas in 1972. Here, we offer an elucidation of the main ideas of Rheticus and suggest – from the comparative study of a concrete case – that he should (...) be considered as a precursor of later similar moves, such as that of Galileo in well-known and better-studied letters. (shrink)