United States Naval Observatory Flagstaff Station - Navy Precision Optical Interferometer

NOFS operates the Navy Precision Optical Interferometer (recently the "P" was modified to mean precision vice prototype) in collaboration with Lowell Observatory and the Naval Research Laboratory at Anderson Mesa, 15 miles south-east of Flagstaff. NOFS (the operational astrometric arm of USNO) funds all principle operations, and from this contracts Lowell Observatory to maintain the Anderson Mesa facility and make the observations necessary for NOFS to conduct the primary astrometric science. The Naval Research Laboratory (NRL) also provides additional funds to contract Lowell Observatory's and NRL's implementation of additional, long-baseline siderostat stations, facilitating NRL's primary scientific work, synthetic imaging (both celestial and of orbital satellites). The three institutions - USNO, NRL, and Lowell - each provide an executive to sit on an Operational Advisory Panel (OAP), which collectively guides the science and operations of the interferometer. The OAP commissioned the chief scientist and director of the NPOI to effect the science and operations for the Panel; this manager is a senior member of the NOFS staff and reports to the NOFS Director.

NPOI is a successful astronomical interferometer of the venerable and proven Michelson Interferometer design. As noted, the majority of interferometric science and operations are funded and managed by NOFS; however, Lowell Observatory and NRL join in the scientific efforts through their fractions of time to use the interferometer; 85% Navy (NOFS and NRL); and 15% Lowell. NPOI is one of the few major instruments globally which can conduct optical interferometry. See an illustration of its layout, at bottom. NOFS has used NPOI to conduct a wide and diverse series of scientific studies, beyond just the study of absolute astrometric positions of stars,; additional NOFS science at NPOI includes the study of binary stars, Be Stars, Oblate stars, rapidly rotating stars, those with starspots, and the imaging of stellar disks (the first in history) and flare stars. In 2007–2008, NRL with NOFS used NPOI to obtain first-ever closure phase image precursors of satellites orbiting in geostationary orbit. In 2009 NOFS and USNO began efforts to finalize acceptance of four additional 1.8-meter telescopes into the NPOI array, which formerly were slated to be a part of the Keck Observatory interferometric array. Under Secretary of the Navy acceptance occurred in November 2010, and these four telescopes were assigned to NOFS. Installation plans were developed in 2010-2012 by the scientific and engineering staffs at NOFS, based on the funded science performed by NOFS and NRL. In 2012 NOFS, with support from USNO, CNMOC and the Chief of Naval Operations' Oceanographer staff, began developing funding and programming plans in order to install the array. NOFS endeavors to facilitate construction starts in the 2012-2015 timeframe.