28. Commission des Nébuleuses et des Amas Stellaires

1. Since the field covered by Commission No. 28 extends over the problems of three very different types of objects—external galaxies, galactic nebulae, and star clusters—it has been proposed occasionally that the Commission might well be subdivided, or possibly eventually split into three separate Commissions. As Trumpler points out, these three fields “have often been grouped together...more on a historical basis than on an actual similarity of the researches... which are more and more drifting apart.” But some members of the Commission have noted that a distinct difference also separates globular clusters and galactic clusters; and that planetary nebulae and dark absorbing clouds involve at times widely different types of investigations. The chairman of the Commission has made a canvass of the opinions of the members and finds that a large majority believe that no division or subdivision is advisable at this time. It is suggested that the organization or reorganization of a Commission should be left to the Union as a whole or to the Executive Committee.</jats:p

28. Commission des Nébuleuses et des Amas Stellaires

During the past three years observational and theoretical work has been uncommonly extensive and fruitful in two of the fields within the interests of Commission 28—namely, the distribution of external galaxies and the analysis of diffuse nebulosity, the latter including interstellar absorbing material. Important work is also under way at a number of observatories in the interpretation of planetary nebulae. Studies of clusters, however, have been limited to a few active workers, and progress has not been rapid in the analysis of individual galaxies.</jats:p