Plaskett Report for March 1925


The observing weather for March has been much better than for the preceding month, a total of 160 plates being secured on 17 nights or parts of nights.The average for the past 5 years for the month of March has been 150 on 17 nights, so that the month has been an average one.

Director J. S. Plaskett observed on 3 nights, obtaining 25 spectra and measured 18 spectrograms for radial velocity. Obtained the period, orbit and least-squares correction of HD 25833. Additional least-squares correction of 21 Cass. Handled the usual administrative work and correspondence.

Assistant Director W. E. Harper observed on 6 nights obtaining 72 spectra. Measured 32 plates for radial velocity. He delivered one lecture. Worked up one orbit (46 Aurigae) and wrote it up for publication. Some time given to absolute magnitudes of A-type stars.

Astronomer H. H. Plaskett secured 16 spectra on 2 nights. Principal work of the month has been securing and measuring check plates of the Orion nebula to test the validity of the fringes found with the etalon. In addition considerable time has been given to the re-arrangement and revision of the mailing list in order to eliminate duds and substitute desirable recipients. The recently bound books have been classified and placed in position in the library.

Astronomer J. A. Pearce observed 6 nights, obtaining 47 spectra. Measured and reduced 32 spectrograms for radial velocity. Computed the orbit of HD 216014 for publication. Prepared 1 lecture for the RASC. Semi-weekly clock corrections.

Astronomical Computer S. N. Hill measured and reduced 50 spectrograms for radial velocity.

Senior Clerk Typist Miss H. R. Keay handled the usual plates, correspondence. accounts, reports. Typed notes on observatories and publication on 45 Aurigae for Mr. Harper. Numbered and entered about 80 new volumes in the library catalogue. Revised, re-arranged and retyped mailing list.

Instrument Maker Foreman T. T. Hutchison assisted in observing on 14 nights. Repaired the shutter cable, painted right ascension numbers and did the usual repair work about telescope.