Aitken, Robert Grant

(b. Jackson, California, 31 December 1864; d. Berkeley, California, 29 October 1951)

astronomy.

During forty years at the Lick Observatory, Aitken was an outstanding observer of double stars, and his New General Catalogue of Double Stars Within 120° of the North Pole (1932) is still a standard work.

Aitken at first intended to become a minister, but his studies in biology and astronomy at Williams College (1883–1887) diverted his interests to science, In 1891 he became professor of mathematics at the University of the Pacific, where there was a small observatory with a six-inch Clark refractor. In 1894 he visited Mt. Hamilton, and the following year returned there as assistant astronomer at the Lick Observatory. He was successively promoted to astronomer (1907), associate director (1923), and director (1930). He retired in 1935.

Aitken’s early work at Lick was routine and varied, but double stars soon came to take up more and more of his time, In 1899 he embarked on a systematic survey of double stars that would provide the basis for statistical investigations. He was soon joined by W.J. Hussey, and together they examined stars given in the Bonner Durchmusterung as not fainter than 9.0 (Aitken) or 9.1 (Hussey) down to 22° southern declination. When Hussey left Lick in 1905, Aitken took over his share of the work and completed the survey in 1915. It resulted in the discovery of over 4,400 new pairs with separations mostly below 5′′, and over two-thirds of these were found by Aitken; he published statistical investigations of this material in 1918 in The Binary Stars. Yet Aitken’s real vocation was the observation of doubles; and in 1920, on the death of Eric Doolittle, he took over the compilation of material for a revision of S.W. Burnham’s 1906 catalog of double stars, a revision that he published in 1932 as complete to 1927, Meanwhile, he devoted much of his time to the popularization of astronomy, and this became his main interest in retirement.

BIBLIOGRAPHY

I. Original Works. Aitken’s works include The Binary Stars (New York, 1918; 2nd ed., rev., 1935) and A NewGeneral Catalogue of Double Stars Within 120° of the North Pole, 2 vols., Carnegie Institute of Washington Publication No.417 (Washington, D.C., 1932), A full bibliography of his articles is in the biographical memoir by Van den Bos (see below).

II. Secondary Literature. Works on Aitken are mainly the numerous obituary notices in astronomical and other journals, of which by far the most comprehensive is that by Willem H. Van den Bos, in National Academy of Sciences, Biographical Memoirs, 32 (1958), 1–30.

Michael A. Hoskin