Gerard van Belle, Lowell Observatory, Gerard T. van Belle, Lowell Observatory, Kaspar von Braun, Lowell Observatory, J. Thomas Armstrong, Naval Research Laboratory, Ellyn K. Baines, Naval Research Laboratory, Henrique R. Schmitt, Naval Research Laboratory, Anders M. Jorgensen, Global Research Enterprises, Nicolas Elias, OAM Solutions, David Mozurkewich, Seabrook Engineering, Rebecca Oppenheimer, American Museum of Natural History, Sergio Restaino, Naval Research Laboratory
Keywords: Optical Systems
Abstract:
The Navy Precision Optical Interferometer (NPOI) is a six-beam long-baseline optical interferometer, located in Flagstaff, Arizona; the facility is operated by a partnership between Lowell Observatory, the US Naval Observatory, and the Naval Research Laboratory. NPOI operates every night of the year (except holidays) in the visible with baselines between 8 and 100 meters (up to 432m is available), conducting programs of astronomical research and technology development for the partners. NPOI is the only such facility as yet to directly observe geostationary satellites, enabling milliarcsecond resolution of these objects. To enhance this capability towards true imaging of geosats, a program of facility upgrades will be outlined. These upgrades include AO-assisted large apertures feeding each beam line, new visible and near-infrared instrumentation on the back end, and infrastructure supporting baseline-wavelength bootstrapping which takes advantage of the spectral and morphological features of geosats. The large apertures will enable year-round observations of objects brighter than 10th magnitude in the near-IR. At its core, the system is enabled by a approach that tracks the low-resolution (and thus, high signal-to-noise), bright near-IR fringes between aperture pairs, allowing multi-aperture phasing for high-resolution visible light imaging. A complementary program of visible speckle and aperture masked imaging at Lowell’s 4.3-m Discovery Channel Telescope, for constraining the low-spatial frequency imaging information, will also be outlined, including results from a pilot imaging study.
Date of Conference: September 15-18, 2015
Track: Optical Systems