Plaskett Report for October 1929


The month was a little above average for observing as 100 plates were secured on 20 nights with a total observing time of 128.7 hours. The ten-year average for the month shows 16 nights with 124.6 hours of observing time and 133 plates.

Approximately 823 persons visited the observatory during the month.

Director J. S. Plaskett did computational work on galactic rotation and writing up paper and preparing addresses on same. Left for the East on the 22nd to attend the meetings of the Associate Committee on Physics and Engineering Physics, National Research Council and will deliver lectures at Toronto and Brooklyn.

[Plaskett’s address in Brooklyn was titled “The Rotation of the Galaxy” and was delivered on November 7, 1929 at Academy of Music, Ed.]

Assistant Director W. E. Harper worked 6 nights securing 26 spectra. Measured for radial velocity 60. Examining agreement of velocities with those of Lick and Yerkes. Administrative duties in absence of Director.

Astronomer J. A. Pearce observed 7 nights, obtaining 37 spectrograms. Measured 42 spectrograms for radial velocity. Prepared and gave 1 seminar talk. Worked on Binary HD 698 and obtained the period.

Astronomer C. S. Beals observed 2 nights, obtaining 9 plates. Developed rotating sector method of sensitivity for use with stellar plates. Began laboratory work on measurement of line intensities. Gave one seminar talk.

Astronomer R. O. Redman revised second orbit of Y Cygni obtained last month. Measured 51 plates. Did preliminary work on ratios of line intensities in order to discriminate between ‘giants’ and ‘dwarfs’ among stars in the K programme. Worked on 5 nights and obtained 28 plates.

Computer S. N. Hill did computational and other related work on B stars. Remeasured 14 broad lines B type spectra.

Clerk-Stenographer Miss L. M. Blake handled correspondence, accounts, envelopes for plates and miscellaneous typing.

Typist Miss L. H. Hawthorn handle correspondence, plate envelopes and typing during the absence of the secretary.

Instrument Maker Foreman T. T. Hutchison assisted in observing on 13½ nights and kept the telescope in running condition. Cleaned and oiled measuring machines.