Plaskett Report for October 1927


The observing weather has been the poorest for the month of October yet experienced at this place.While observations were secured on 11 nights yet only a couple of these could be classified as good.61 plates were secured with a total of 64.2 hours exposure. Against this the eight-year average shows 17 nights, 148 plates and 133.9 hours of observing.

Director J. S. Plaskett performed computational and other work on the Rotation of the Galaxy as determined from the B and O stars and preparation of paper on above subject, Handled the usual administrative work and correspondence.

Assistant Director W. E. Harper worked 5 nights obtaining 29 plates. Measured for radial velocity 40. Prepared summary of observatory’s work for Popular Astronomy”. Gave one staff talk. Other miscellaneous work.

Research Astronomer H. H. Plaskett worked 4 nights obtaining 11 plates, 23 spectra. Some time spent putting auxiliary standard spectra on III prism plates. Measure spectrophotometrically the emission line intensities of a number of lines in Z Andromedae and determined the magnitude of the nebula.

Astronomer J. A. Pearce observed 2 nights obtaining 21 spectrograms. Worked on orbit of HD 176833 and on statistics of double-lind orbits. Prepared and gave 1 talk before staff on “Class B Stars of Abnormal Colour Index”

Astronomer C. S. Beals completed measurement of Oxygen lines on grating plates in the region λ4300-4700. Measured a band spectrum associated with silver in the region λ2279-3373

Astronomical Computer S. N. Hill spent time computing the total proper motion and position angle of proper motion vector for B-type stars. Remeasured for radial velocity 6 B-type spectrograms. Making two small scale graphs to accompany article for publication. Work in connection with the library.

Senior Clerk-Stenographer Miss L. M. Blake handled the usual reports, accounts and correspondence. Spectrum plates and envelopes; astronomical typing; work on catalogue of mailing list and library work. Typed and prepared for printer Volume IV, Number 5 Publications of this observatory.

Instrument Maker Foreman T. T. Hutchison assisted in observing on 6½ nights. Replaced spider threads in measuring engine with larger ones. General repair work to telescope.