Book contents
- Frontmatter
- PREFACE
- Contents
- LIST OF THE PLATES
- INSTRUMENTS
- LIST OF ABBREVIATIONS ADOPTED IN THIS WORK
- The Negatives–measurement of the photographic field–scales of the enlargements
- Epoch of the Fiducial Stars, A.D. 1900
- Table
- Deterioration of the Negatives
- Effects of Atmospheric Grlare and of Diffraction upon the films of photographic plates
- Arrangement of the Plates
- Method for micro-puncturing the photographic discs of stars on plates to obtain their optical centres for purposes of measurement
- Star Catalogues and Photographic Charts
- Duration of the effective exposures given to photographic plates in the 20-inch reflector
- Are the millions of Stars and the numerous Nebulosities, which are now known to exist, limited in number and extent; and do they consequently indicate that the Universe, of which the Solar System constitutes a part, is only one member of a greater Stellar Universe?
- The Evolution of Stellar Systems
- Inferences suggested by examination of the Photographs
- Description of the Photographs
- Description of the Photographs
Star Catalogues and Photographic Charts
Published online by Cambridge University Press: 05 July 2011
- Frontmatter
- PREFACE
- Contents
- LIST OF THE PLATES
- INSTRUMENTS
- LIST OF ABBREVIATIONS ADOPTED IN THIS WORK
- The Negatives–measurement of the photographic field–scales of the enlargements
- Epoch of the Fiducial Stars, A.D. 1900
- Table
- Deterioration of the Negatives
- Effects of Atmospheric Grlare and of Diffraction upon the films of photographic plates
- Arrangement of the Plates
- Method for micro-puncturing the photographic discs of stars on plates to obtain their optical centres for purposes of measurement
- Star Catalogues and Photographic Charts
- Duration of the effective exposures given to photographic plates in the 20-inch reflector
- Are the millions of Stars and the numerous Nebulosities, which are now known to exist, limited in number and extent; and do they consequently indicate that the Universe, of which the Solar System constitutes a part, is only one member of a greater Stellar Universe?
- The Evolution of Stellar Systems
- Inferences suggested by examination of the Photographs
- Description of the Photographs
- Description of the Photographs
Summary
The catalogues of stars are numerous, as will be seen by referring to the list given in Chambers' “Handbook of Descriptive Astronomy,” where 170 are enumerated between that by Hipparchus in the year b.c. 128 and the year a.d. 1876; besides these there are catalogues of nebulæ, and atlases or charts of stars.
In considering these records one is impelled to ask the questions–Have these vast stores of computative and descriptive literature, the product of great energy expended in physical and mechanical operations, and of much thought, been utilized in the advancement of astronomical knowledge to a degree commensurate with the labour and cost of their production?
Or, have the astronomers been deterred from undertaking the work of correlation, on a comprehensive scale, because they know that there is a considerable margin of probable error in all these records–particularly in those of earlier date than the middle of the present century–they therefore judge it would be unprofitable to devote their time to making the necessary examinations. They know that when they find differences to exist in the records, it would be uncertain whether they were objective, or were only the result of human errors.
In my own experience I have found differences to exist between photographs and carefully prepared modern charts of stars–differences in the position angles, in distances, in the magnitudes of the stars and in the structure and extent of nebulosities, which were most probably due to errors in charting.
- Type
- Chapter
- Information
- Photographs of Stars, Star-Clusters and NebulaeTogether with Records of Results Obtained in the Pursuit of Celestial Photography, pp. 18 - 20Publisher: Cambridge University PressPrint publication year: 2010First published in: 1899