Commission 34. (Solar Parallax.)

Extract

The President first summarized the present position of the work of determining the solar parallax as given in the Report.

In connection with the determination of the positions of the reference stars it was stated that within the next six months or so the reductions of all the series of photographs will be completed and it will then be possible to co-ordinate the results and publish a definitive list of secondary comparison stars. At the same time it has become apparent that there are appreciable errors in the positions based on the meridian observations of some of the primary stars given in Prof. Kopff’s catalogue. By co-ordinating the measures of the several series of path plates it will be possible to derive corrections to the positions of the Kopff stars, which will still keep them on the system adopted by Prof. Kopff, but will improve their homogeneity.