Boss, Lewis

(b. Providence, Rhode Island, 26 October 1846; d. Albany, New York, 5 October 1912)

positional astronomy.

Boss, who was honored by the Royal Astronomical Society for his “long-term work on the positions and proper motions of fundamental stars,” had little, if any, academic training for this work. As a student at Dartmouth College he followed a classical course, but also frequented the observatory, where he learned to handle astronomical instruments and to reduce observations. After graduation he worked as a clerk in various government offices in Washington, D.C., and frequented the U.S. Naval Observatory, from which he borrowed small astronomical instruments.

In 1872 Boss was appointed assistant astronomer for the survey of the 49th parallel, between the United States and Canada; his job during the next four years was to locate, by celestial observations, latitude stations from which the surveyors could work. His observations with a zenith telescope led him to realize that latitude determinations can be no more accurate than the stellar declinations on which they are based. Therefore, while the survey was still in progress, Boss developed a homogeneous system of declinations, as free as possible from systematic errors resulting from faulty observations and methods of reduction. From a comparison of numerous star catalogs he devised tables for the systematic correction of each, as well as a new catalog of the declinations and proper motions of 500 stars, which was adopted by the American Ephemeris in 1883.

In 1876 Boss became director of the Dudley Observatory, a position he held for the rest of his life. His first major project at Albany, New York, was observation and reduction of a zone for Leipzig’s Astronomische Gesellschaft. By determining his magnitude equation and investigating the flexure of, and division corrections needed by, each of the two circles of the Pistor and Martins meridian circle, Boss was able to keep his probable errors to less than ± 0″.6 for each observation—well within the limits expected for the society’s catalog. Although he had little assistance, and started ten years after the work on many other zones was begun, Boss was the first to finish to finish his zone. A comparison of the zone results with earlier observations led him to realize the need for an extensive analysis and comparison of the many available starcatalogs, in order to make a reliable determination of proper motions.

The outcome of this study—financed in large part by the Carnegie Institution, which in 1906 established a department of meridian astrometry under the direction of Boss, and later of his son Benjamin—was published in numerous papers and four great catalogs. The Preliminary General Catalogue (1910) included information no 6, 188 bright stars. The San Luis Catalogue (1928) was based on observations of 15, 333 stars made with the great meridian circle of the Dudley Observatory, moved temporarily to Argentina. The Albany Catalogue (1931) included 20, 811 stars observed with the meridian circle at Albany, and the General Catalogue of 33, 342 Stars (1937) contains “the standard positions and proper motions of all stars brighter than the seventh magnitude, extending from the north to the south pole, and some thousands of additional fainter stars promising to yield reasonably accurate proper motions.”

While at Dudley, Boss undertook several other projects. He computed the orbits of many comets and in 1881, under the pseudonym of Hipparchus III, won the $200 Warner Prize for the best essay on comets. The following year Boss took charge of the U.S. government party sent to Santiago, Chile, to observe and photograph the transit of Venus. From 1883 to 1906 he served as superintendent of weights and measures of the state of New York. In 1893 Boss moved the Dudley Observatory to a more astronomically advantageous location in Albany. With experience gained from editing and managing the daily Albany Morning Express, in 1897 Boss became associate editor, and in 1909 editor, of the Astronomical Journal.

Among Boss’s many honors besides the gold medal of the Royal Astronomical Society (1905), the Lalande Prize of the Paris Académie des Sciences (1911), and membership in the National Academy of Sciences (1889), the Königlich Preussischen Akademie der Wissenschaften (1910), and the Imperial Academy of Sciences of St. Petersburg.

BIBLIOGRAPHY

Among Boss’s writings is his prize-winning essay, “Comets: Their Composition, Purpose, and Effect Upon the Earth,” in History and Work of the Warner Observatory, 1883–6 (Rochester, N.Y., 1887), pp. 25–30. The four star catalogs, all prepared at the Dudley Observatory, Albany, N.Y., and published by the Carnegie Institution of Washington, D.C., are the Preliminary General Catalogue of 6188 Stars (1910), by Lewis Boss; San Luis Catalogue of 15, 333 Stars (1928), by Lewis and Benjamin Boss; Albany Catalogue of 20, 811 Stars (1931), and General Catalogue of 33, 342 Stars (1936–1937), both the work of Benjamin Boss.

Additional information and a bibliography of his scientific writings is in Benjamin Boss, “Biographical Memoir of Lewis Boss, 1846–1912,” in Biographical Memoirs of the National Academy of Sciences, IX (Washington, D.C., 1920), 239–260. Also of value is “Address Delivered by the President, H. H. Turner, on Presenting the Gold Medal of the Society to Professor Lewis Boss,” in Monthly Notices of the Royal Astronomical Society, 65 (1904–1905), 412–425.

Deborah Jean Warner