1 U.S. Naval Observatory Washington, DC 20392-5420 This report covers the period July 2001 through June dynamical astronomy in order to meet future needs. J. 2002. Bangert continued to serve as Department head. I. PERSONNEL A. Civilian Personnel A. Almanacs and Other Publications Marie R. Lukac retired from the Astronomical Appli- cations Department. The Nautical Almanac Office ͑NAO͒, a division of the Scott G. Crane, Lisa Nelson Moreau, Steven E. Peil, and Astronomical Applications Department ͑AA͒, is responsible Alan L. Smith joined the Time Service ͑TS͒ Department. for the printed publications of the Department. S. Howard is Phyllis Cook and Phu Mai departed. Chief of the NAO. The NAO collaborates with Her Majes- Brian Luzum and head James R. Ray left the Earth Ori- ty’s Nautical Almanac Office ͑HMNAO͒ of the United King- entation ͑EO͒ Department. dom to produce The Astronomical Almanac, The Astronomi- Ralph A. Gaume became head of the Astrometry Depart- cal Almanac Online, The Nautical Almanac, The Air ment ͑AD͒ in June 2002. Added to the staff were Trudy Almanac, and Astronomical Phenomena. The two almanac Tillman, Stephanie Potter, and Charles Crawford. In the In- offices meet twice yearly to discuss and agree upon policy, strument Shop, Tie Siemers, formerly a contractor, was hired science, and technical changes to the almanacs, especially to fulltime. Ellis R. Holdenried retired. Also departing were The Astronomical Almanac. Charles Crawford and Brian Pohl. Each almanac edition contains data for 1 year. These pub- William Ketzeback and John Horne left the Flagstaff Sta- lications are now on a well-established production schedule. tion. The Astronomical Almanac is available 1 year prior to the Correction to 1999/2000 Observatory Report: Alan D. year of the edition, The Air and Nautical Almanacs are avail- Fiala ͑Astronomical Applications Department͒ retired as able 9 months prior, and Astronomical Phenomena is avail- chief of the Nautical Almanac Office in June 2000. David R. able 3 years prior. During the reporting period, the almanacs Florkowski ͑EO͒ also retired. Baki Iz left the EO staff. for 2003 and Astronomical Phenomena for 2004 were pub- Corrections to 2000/2001 Observatory Report: Brent lished. At the end of the reporting period, the next editions Archinal ͑EO͒, and Marshall Eubanks ͑EO͒ did not retire, were in preparation and on schedule. All the publications are but left for employment elsewhere. James O. Martin ͑EO͒ sold in the United States by the U.S. Government Printing did retire. David Johns joined the TS staff. Bryan N. Dorland Office ͑http://bookstore.gpo.gov/index.html͒. The Astronomi- joined the AD staff and Robert B. Hindsley left. Student cal Almanac Online, a Web site that complements The Astro- Temporary Employees included William Neal Potter ͑TS͒ nomical Almanac, went live in January 2002. M. Lukac, R. and Danell Sorinmade ͑Library͒. Casey Johnson was an aide Miller, S. Stewart, M. Stollberg, and Howard participated in in TS. the production of the annual publications. There are four major efforts ongoing within the NAO: the B. Engineering Apprenticeship Program first to update and enhance the science content of The Astro- nomical Almanac; the second to revise the Explanatory ͑ ͒ The United States Naval Observatory USNO summer Supplement to The Astronomical Almanac; the third to con- intern program for high school and college students contin- tinue adapting the products to meet the needs of the U.S. ued. This program, called the Science and Engineering Ap- Navy and the worldwide scientific community; and the ͑ ͒ prenticeship Program SEAP , is sponsored by the Depart- fourth to streamline and update production. All are multi- ͑ ͒ ment of Defense DoD and managed by George Washington year efforts and involve the entire staff of the NAO. University. For the summer of 2001, under the direction of During this reporting period, there were several improve- ͑ ͒ ͑ ͒ D. Pascu AD and L. Schmidt TS , the interns and the ments to the science and technical algorithms in the alma- ͑ departments they worked in were Shawnette Adams Public nacs. These improvements will be implemented in future edi- ͒ ͑ ͒ ͑ ͒ Affairs , Calvin Ashmore Library , Andrew Cenko AD , tions of The Astronomical Almanac. As part of the ͑ ͒ ͑ ͒ ͑ ͒ Arthur Hyder TS , Dean Kang AD , Anne Kurtz TS , continuous review of the underlying science, Stollberg incor- ͑ ͒ ͑ ͒ ͑ ͒ Steven Movit AD , Paul Ries AD , Diana Seymour AD , porated the latest orbital parameters in all the planetary sat- ͑ ͒ ͑ ͒ Sabrina Snell AD , and Lim Vu EO . ellite algorithms used for The Astronomical Almanac. Changes in The Astronomical Almanac for 2004 include re- II. ASTRONOMICAL APPLICATIONS DEPARTMENT moving the International Astronomical Union ͑IAU͒ 1976 The Department continued to perform its core mission of list of astronomical constants from the printed book and providing practical astronomical information and data via placing it on the complementary Web site. In place of this printed publications, software products, and the World Wide list, the printed book will list the constants ͑and references͒ Web. The Department’s products are used by the U.S. Navy, used in the computations. Data for the obsolete Besselian other components of the U.S. government, the international day numbers will be removed. The 2004 edition also will scientific community, and the general public. The Depart- contain two new tables: one for bright double stars ͑pro- ment also maintains a research program in positional and duced by Stewart using data provided by B. Mason ͓AD͔͒, 2 ANNUAL REPORT and one for bright gamma ray sources ͑produced by Stoll- software routines now used in all production code. Lukac berg and N. Gehrels, NASA/GSFC͒. Future plans include streamlined and documented the already rigorous data veri- improving the methodology used to compute the orbital po- fication and proofing process. Miller simplified the graphics sitions of short-period ͑Ͻ 90 days͒ satellites. Stollberg is production of the eclipse maps and the satellite diagrams. working closely with HMNAO staff on this revision. The The NAO still receives written requests for special astro- new method uses a mixed-function expansion solution for a nomical data tables, although data provided through the De- satellite orbit that produces coefficients suitable for a partment’s Web site ͑http://aa.usno.navy.mil͒ have greatly straightforward production of offsets for every day of the decreased the number of such requests. Lukac, Chief Quar- year. This mitigates the technical difficulties of the older termaster B. Wass, and Y. Holley handled these requests. methods that cannot adequately handle short-period satel- lites. The 2005 edition will use the mixed function method B. Software Products for the short-period satellites. Howard presented papers on the status of and future plans for The Astronomical Almanac The Product Development Division, headed by N. Oliv- ersen, is responsible for the Department’s software products at the January 2002 AAS Meeting and the April 2002 Divi- and the Department’s Web site. sion on Dynamical Astronomy ͑DDA͒ Meeting. STELLA ͑System to Estimate Latitude and Longitude As- The almanac offices have a plan to implement the relevant tronomically͒, a celestial navigation software tool developed resolutions of the XXIVth IAU General Assembly ͑2000͒. by USNO specifically for the U.S. military, continues to be Bangert presented a paper on this subject at the International widely used throughout the Navy and Coast Guard. The cur- Earth Rotation Service ͑IERS͒ Paris Workshop in April 2002. rent version of STELLA ͑Version 2.0͒ is a Windows/PC ap- Resolution B1.6 encourages the use of the new IAU 2000 plication, which can perform calculations over an extended precession-nutation theory. This theory was not received in time period ͑1970-2010͒. W. Harris made significant time to incorporate it into the 2004 edition of The Astronomi- progress in the development of a version of STELLA for cal Almanac. Incorporation into future editions will occur handheld computers running the Palm OS. Most major de- when this theory and the accompanying precession theory sign challenges have been solved and a prototype version of are available. Resolution B1.8 recommends that the IERS this software should be ready for demonstration and testing take steps to implement the use of the ‘‘non-rotating origin’’ by fall 2002. There is strong interest in a Palm version of ͑NRO͒ in the Geocentric Celestial Reference System, and STELLA by several Navy organizations and by the Coast that this point be designated as the Celestial Ephemeris Ori- Guard. gin on the equator of the Celestial Intermediate Pole. The MICA ͑Multi-year Interactive Computer Almanac͒ is a implications of this resolution on the contents of The Astro- software tool that provides high-precision astronomical data nomical Almanac remain under review by both the NAO and in tabular form for the time interval 1990-2005. MICA 1.5 is HMNAO. The almanac offices plan a gradual introduction of available as a DOS application for Windows/PC computers, these concepts, especially of the coordinate systems pre- and as an application for Mac OS computers. Willmann-Bell, sented, over a period of several years. Thus, The Astronomi- Inc. ͑http://www.willbell.com/͒ distributes MICA for USNO. cal Almanac for 2004 will not incorporate these two resolu- Design and development work continued on MICA 2.0, tions. which will be a major upgrade of this software. The new The information contained in The Astronomical Almanac version will feature a revamped user interface and several is highly technical and covers a diverse range of topics. To new capabilities. New capabilities will include more sophis- avoid excessive, repetitive detail, the book omits a great deal ticated rise/set/transit computations, positions of selected mi- of background material.