Plaskett Report for February 1924

The observing weather during February has been very poor for this time of year. The dome was opened on 11 nights but useful observations obtained on 6 nights only and  9 plates secured. Special observations with an etalon requiring long exposures on the Orion Nebula account for the small number obtained. The reduction and office work has made good progress.

Director J. S. Plaskett did no observing work. Completed preparation for printing of Volume II, Number 16. Made enlarged spectra of 41 spectrograms and prepared a copy for three plates from above publication from prints of these. Combined the enlarged spectra into transparencies for exhibition here and at the BAA meeting in Toronto. Usual correspondence, etc.

[Plaskett gave a talk to the Vancouver Institute on Stellar Evolution, Ed]

Sat, Feb 9, 1924 – 24 · The Victoria Daily Times (Victoria, British Columbia, Canada) ·

Research Astronomer W. E. Harper compared absolute magnitudes of 1080 stars with determinations of Young and reexamined the discordant ones. Divided them into 50 groups and applied proper motion methods to check up results. Obtained corrections for groups of giant stars by Kapteyn’s correction formula.

Thu, Feb 7, 1924 – 9 · The Victoria Daily Times (Victoria, British Columbia, Canada) ·
Astronomer R. K. Young divided all stars in program whose proper motion and radial velocity were known into groups according to the value of the absolute magnitude determined here and made a solution for mean values to be used to determine systematic errors. The results indicate slight corrections to A-type and a few other types but few alterations were necessary. Commenced preparation of the final tables for the printer.

Astronomer H. H. Plaskett observed parts of 6 nights and obtained 4 spectrograms of the Orion Nebula through etalon. Worked on theory of Fabry and Perot interferometer and translated long German paper on intensity distribution in spectral lines. Freshly silvered plates of the etalon several times, adjusted it and made test spectra in preparation for night observations on 15 nights.

Computer S. N. HIll made calculations of the proper motion components of a number of stars in preparation of Volume II, Number 1 – Harper and Young’s publication

Senior Clerk Typist Miss H. R. Keay handled the usual reports, plates, accounts and correspondence. Read the galley proof of Volume II, Number 15. Continued compilation new programme B-type stars. Copy work in conjunction with Volume II, Number 1. Prepared about 75 volumes of periodicals for binding and entered a number of new books in the library catalogue.