With 14 associates of the department of Astronomy, Dr. Harlow Shapley, Director of the Harvard Observatory, attended two international conferences this summer and in two lectures maintained the reputation this college has of being the foremost in this hemisphere in astronomical research.
At the meeting of the International Astronomical Union in Stockholm, Sweden, from August 3 to 10, papers were delivered by three men from Harvard. Dr. Shapley spoke on "The Distribution of Galaxies and the Absorption of Light in space." He confirmed previous indications that our own discshaped galaxy, the Milky Way, is surrounded by an immense, low-density globe of scattered stars.
The Harvard Observations show that this Milky Way "globe" has a diameter of about 80,000 light years (a light year is the distance light travels in a year at the rate of 186,000 miles a second). The diameter of the flat disc of the Milky Way in which nearly all the stars of the system are located, is of the order of 100,000 light years.
These conclusions were made by observing the magnitude of over 2000 variable stars in all parts of the Milky Way system. Since stars of this type all have about the same candle-power--about 200 times that of the sun--their magnitude determines their distance.
Bart J. Bok, assistant professor of Astronomy, spoke on "The Structure of the Milky Way" at the same meeting, as did Donald H. Menzel, associate professor of Astronomy on "The Interpretation of Absorption Lines."
British Colloquy Also
At the conference of the British Association for the Advancement of Science, held in Cambridge, England, from August 17 to 23, Dr. Shapley presented a second paper on "The Nature of the Inner Metagalaxy." In this talk he reported the discovery by Harvard of a conspicuous irregularity in the distribution of galaxies, or island universes, in the southern sky. This discovery, he said, is of fundamental importance, for, although it does not prove the theory that the universe is expanding, it eliminates conflicting theories based on counts of galaxies.
More than 100,000 galaxies were studied in the Harvard survey, covering an are about 200,000,000 light years long at a distance of 13,000,000 light years from the earth. Dr. Shapley pointed out that the density here is twice as great as in some regions of the sky.
The other 11 representatives from Harvard included Dr. Annie J. Cannon, committee on stellar spectra; Dr. Dorrit Hoffleit, committee on meteors and related problems; Miss Jenka Mohr, committee on nebulae and star clusters; and Dr. Theodore E. Sterne, Dr. Martin Schwarzschild, Dr. Leo Goldberg, Miss Henrietta Swope, Miss Constance Boyd, Mrs. R. Newton Mayall, Miss Rebecca Jones, and James G. Baker.
Dr. Shapley was on the committees on stellar parallaxes, stellar photometry, variable stars, nebulae and globular clusters, and stellar statistics. Dr. Bok was on the committees on stellar statistics and on stellar radial velocities. Dr. Menzel was on the committees on solar radiation, solar eclipses, and spectral photometry.