Charles Worley, Astronomer at the US Naval Observatory, died unexpectedly on December 31, 1997, after a short illness. He was born on May 22, 1935 in Iowa City, Iowa, and grew up in Des Moines, where his father was a doctor. He became interested in astronomy at age nine. His first observational work as an amateur astronomer was the plotting and recording of more than 10,000 meteors for the American Meteor Society. Continuing his love for astronomy, Worley attended Swarthmore College, where he took part in the parallax program and met the other love of his life, his wife Jane. He obtained a BA in mathematics from San Jose State College in 1959 and worked for Lick Observatory (1959-61) as a research astronomer under a Naval Research (ONR) grant to observe double stars.
Since arriving at USNO in 1961, Worley was the motive force behind an extensive program of double star observation (having himself made the second largest number of double star measurements ever achieved by one person), instrumental innovation, and double star cataloging. He quickly gained recognition as one of the world's leading experts in the field of double star astronomy
In 1965, Charles arranged for the Index Catalogue of Visual Double Stars (IDS) to be transferred from Lick Observatory to USNO. This data base became a truly comprehensive resource under his guidance and is formally recognized as the primary source of double star data by the International Astronomical Union (lAU) He updated the database continuously, adding 290,400 observational records to the original 179,000 and increasing the original 64,000 systems by an additional 17,100, through careful literature searches and extensive communication with other double star observers throughout the world During the past three years, Worley extended the scope and utility of the database, now known as the Washington Double Star Catalog (WDS) by adding accurate photometric data, improved spectral types, and identification information The project was completed in 1996, and the revised WDS is available on the world wide web. Most recently, he oversaw the addition of 15,000 Hipparcos Catalogue double stars into the WDS. Requests for information from the WDS database arrive daily from astronomers all over the world
In collaboration with William Finsen and later Wulff Heintz, Charles Worley published two Catalogs of Orbits of Visual Binary Stars, the second in 1983. He was working on the third version at the time of his death. In recent years, an accurate knowledge of double and multiple star separations, position angles, and orbital motions has become increasingly important to astronomy. It is now realized that, not only must double stars be identified and calibrated in order to produce the best astrometric catalogs, but also the varying center of emission at different wavelengths must be taken into account to meet modern high-precision astrometric needs. For Worley's contribution to this aspect of astrometry, he received the 1994 USNO Simon Newcomb Award for Scientific Achievement
In 1991, Charles was elected Vice-President of Commission 26 (Double and Multiple Stars) of the IAU, and he served as President of that Commission for the 1994-97 term. He was also a member of IAU Commission 5, the American Astronomical Society, including the Historical Astronomy Division, and of the Royal Astronomical Society. He was an active supporter of the amateur community, published a series of articles in Sky and Telescope, and produced the double star sections of The Observer's Handbook.
During his career, Charles made over 40,000 measures of double and multiple stars using the USNO filar micrometer on telescopes in the northern and southern hemispheres. In 1990, he obtained a speckle interferometer, in order to improve the accuracy of double star measurements. From 1990 onward, he oversaw improvements in both instrumentation and software implementation that resulted in making the USNO the world's second largest producer of speckle observations of double stars. Under Worley's direction, more than 9,200 observations of 1,100 systems with separations down to 0.2 arcsec (the theoretical limit of the 26-inch refractor) were obtained. Recently, his speckle interferometer has been used to survey problem stars from the Hipparcos Catalogue with the McDonald 2.1-meter Otto Struve Telescope.
Worley's special interest in nearby stars led to the discovery of 39 new, cool, stellar companions, improving the census or the solar neighborhood and our knowledge of the lower end of the initial mass function. From 1954 to 1997, he published some 75 professional papers, primarily on double star astronomy and gave numerous invited presentations at meetings. He was known for the exacting standards and high quality best typified by his paper challenging other double star observers, "Is This Orbit Really Necessary?"
We are reminded of one of Charles's favorite quotes from Paul Couteau's book Observing Visual Double Stars, "Do not forget that an astronomer who observes perfect images visually is a wild beast who devours his prey. Do not disturb him under any pretext. Let nature take its course"
Charles will be sorely missed by his many friends and colleagues, who had been planning the sort of gentle celebration he would have appreciated of his retirement. which had been scheduled to take place just days after his death.
Photo (available in PDF version) courtesy of Mrs. Jane Worley.