http://oac.cdlib.org/findaid/ark:/13030/tf7779n8v9 No online items Frederick Hanley Seares Papers: Finding Aid Processed by Ronald S. Brashear, completed February 24, 1998; machine-readable finding aid created by Xiuzhi Zhou in 1998; supplementary encoding and revision by Diann Benti in June 2017. The Huntington Library, Art Collections, and Botanical Gardens Manuscripts Department 1151 Oxford Road San Marino, California 91108 Phone: (626) 405-2129 Email: [email protected] URL: http://www.huntington.org © 1998 The Huntington Library. All rights reserved. Frederick Hanley Seares Papers: mssSeares papers 1 Finding Aid Overview of the Collection Title: Frederick Hanley Seares Papers Dates (inclusive): 1909-1945 Bulk dates: 1909-1940 Collection Number: mssSeares papers Creator: Seares, Frederick Hanley, 1873-1964. Extent: Approximately 10,000 items in 21 boxes Repository: The Huntington Library, Art Collections, and Botanical Gardens. Manuscripts Department 1151 Oxford Road San Marino, California 91108 Phone: (626) 405-2129 Email: [email protected] URL: http://www.huntington.org Abstract: This collection contains the papers of Frederick Hanley Seares (1873-1964), a staff astronomer at the Mount Wilson Observatory known for his photometric studies and his editorial work. Language: English. Access Open to qualified researchers by prior application through the Reader Services Department. For more information, contact Reader Services. Publication Rights The Huntington Library does not require that researchers request permission to quote from or publish images of this material, nor does it charge fees for such activities. The responsibility for identifying the copyright holder, if there is one, and obtaining necessary permissions rests with the researcher. Preferred Citation [Identification of item]. Frederick Hanley Seares Papers, The Huntington Library, San Marino, California. Provenance Deposit, Observatories of the Carnegie Institution of Washington Collection, 1988. Approximately fifty additional separate collections form the Mount Wilson Papers of the Observatories of the Carnegie Institution of Washington and are available for research in the Huntington Library. Processing/Project Information Cataloging of the papers was completed in 1989 prior to their transfer to the Huntington. Biographical Note Frederick Hanley Seares (1873-1964), staff astronomer at the Mt. Wilson Observatory, was involved in most of the administrative and research activities of the Observatory. Highly regarded for his photometric studies and his editorial work, Seares was a prominent figure in astronomy during the first half of the twentieth century. The papers in this collection begin in 1909, when he arrived at Mt. Wilson, and end in 1945, when he ended his affiliation with the Observatory. Seares was born on May 17, 1873, on a farm near Cassopolis, in the southwest corner of Michigan. In 1878, his parents, Isaac Newton Seares and the former Ella Ardelia Swartwout, moved the family to Iowa. They moved again in 1887 to Pasadena, California, where Isaac Seares became involved in the real estate and insurance business. Frederick Seares enrolled at the new Pasadena High School where he was one of its first six graduates in 1890. Seares then matriculated at the University of California in Berkeley and studied under Armin Otto Leuschner. Graduating in 1895 with a B. S. degree (with honors), Seares remained at Berkeley as a Fellow and then Instructor. While at Berkeley, Seares met and on May 28, 1896, married Mabel Urmy, a teacher at Miss Head's School for Girls. In 1899, Seares went to Europe to continue his studies, a practice common among young American scientists of this time. He was accompanied by his wife and they spent one year at the University of Berlin and a second year at the Sorbonne in Paris. Seares's only child, Richard Urmy Seares, was born while the couple resided in Paris. They returned to the United States in 1901, and Seares quickly obtained a position as Professor of Astronomy at the University of Missouri and Director of the Laws Observatory in Columbia. For the next eight years, Seares updated the equipment at the Laws Observatory and engaged in a rich program of astronomical research. Frederick Hanley Seares Papers: mssSeares papers 2 Finding Aid The major turning point in Seares's career came in 1909 when George Ellery Hale invited him to join the staff of the Mt. Wilson Observatory. The new 60-inch reflecting telescope had just come into use on Mt. Wilson, greatly expanding the scope of the Observatory's research. With Walter Sydney Adams being promoted to the head of the new Department of Stellar Spectroscopy, Seares replaced Adams as head of the Computing Division. In addition, Seares was given editorial charge of the Observatory's publications as well as telescope time on the 60-inch to pursue research in stellar photometry. Mt. Wilson's Computing Department consisted almost entirely of women. Most of them were college-educated with training in mathematics and some experience at their college observatories. Their work consisted of tedious measuring of the wavelengths of spectral lines, stellar positions, or stellar brightness (magnitudes). Located exclusively at the Observatory's office building in Pasadena, the computers' work was so involved that they were often given joint authorship in the astronomers' published papers. Occasionally, a promising young male with a Ph.D. in astronomy would be hired as a computer so that he could be available when a staff position would be created. The men might also be a computer in order to have a summer job between school years. As head of the Department, Seares corresponded greatly with potential computers and this material is in eleven folders separated from his general letters. Included in this section are letters of recommendation from various individuals. From 1904 to 1948, Mt. Wilson Observatory issued its astronomers' published papers as Contributions from the Mount Wilson [Solar] Observatory.Even though these papers were published elsewhere (mostly in the Astrophysical Journal or Publications of the Astronomical Society of the Pacific),Hale felt the necessity of having a separate identity for his observatory's publications. As a consequence, he wanted to have one person take care of editing his staff's papers in order to provide some type of consistency. This became Seares's job, and he was highly praised by his colleagues in his ability to turn their work into polished scientific papers, in some cases practically re-writing them to do so. Seares would then submit the papers to the various journals and then correct the proofs. In addition, in 1927 he became a Collaborating Editor and in 1934, Associate Editor, of the Astrophysical Journal.In his papers, therefore, there is a great deal of correspondence with the other editors of this journal, Edwin Brant Frost, Henry Gordon Gale and Otto Struve. There is also a large amount of correspondence with the staff of the Carnegie Institution of Washington's Division of Publications and Edwin Bidwell Wilson, the editor of the publications of the National Academy of Sciences. Along similar lines, Seares was given the task of building up the Observatory's library. Much of his Miscellaneous correspondence consists of his efforts in obtaining material for the library as well as requests from others for copies of the Observatory's publications. In recognition of his administrative abilities, Adams, Mt. Wilson's second Director, appointed Seares Assistant Director in 1925. Until his retirement in 1940, Seares would be in charge of the observatory whenever Adams was away (which was not that often) and some of his correspondence reflects this position. While about one-half of Seares's papers deals with administrative matters, the remainder covers his scientific work. At the Laws Observatory, Seares had gained experience in the field of photometry (measuring the brightness of stars and other celestial bodies). Upon his arrival, he became involved in the photometric research planned for the new 60-inch telescope. The central figure in Mt. Wilson's photometric plans was the Dutch astronomer Jacobus Cornelius Kapteyn. Kapteyn was the leading authority in the field of statistical astronomy. In statistical astronomy, the astronomer worked with a selected statistical sample of stars. Since the stars were too numerous to deal with one at a time, an astronomer would concentrate on a manageable number of stars and extrapolate results for all the stars based on his or her sample. In this way, a research program could be completed within an astronomer's lifetime. In 1906, Kapteyn proposed a scheme of selecting 252 "Selected Areas" spread out over regular intervals across the sky. With international cooperation, the stars in these areas could be studied in detail in order to gain knowledge about the entire Milky Way. When the 60-inch telescope entered service in 1909, it was the most powerful telescope in the world at the time. Kapteyn persuaded Hale to devote some of its time to taking photographs of the 139 Selected Areas within its reach. These photographic plates would then be sent to Kapteyn at Groningen where they could be analyzed. Since the 60-inch telescope would reveal stars fainter than any previously measured, Seares studied the telescope's photographic characteristics in order to develop a proper measurement of stellar magnitudes. After comparisons with other standards of stellar brightness measurements, Seares realized that the prevailing methods of measuring stellar magnitudes were not able to provide him with the accuracy and consistency that he demanded. Starting from scratch, Seares undertook the Herculean task of defining the proper methods and standards of in-focus photographic photometry. He was soon able to establish a common ground for his results and the Harvard North Polar Sequence (a list of magnitudes for stars near the North Celestial Pole. These stars were used since they were always visible to any Northern Hemisphere observatory). Seares began measuring the magnitudes of the stars in the Selected Areas with the assistance of other astronomers at Mt.