John McGraw (University of New Mexico), Mark R. Ackermann (University of New Mexico), Tom Williams (University of New Mexico), Peter C. Zimmer (University of New Mexico), Walter Gerstle (University of New Mexico), M. Suzanne Taylor (University of New Mexico), Jon Turner (University of New Mexico), Julie Smith (University of New Mexico), Justin Linford (University of New Mexico), G. Fritz Benedict (The University of Texas at Austin), Stephen C. Odewahn (The University of Texas at Austin), Lt. Col. Charles J. Wetterer (US Air Force Academy), Gary G. Gimmestad (Georgia Tech Research Institute), Victor L. Gamiz (AFRL/DE), Capt. David Frick (AFRL/DE), Jeffrey R. Pier (US Naval Observatory, Flagstaff), Charles F. Claver (National Optical Astronomy Observatory), Dean C. Hines (Space Science Institute), Jens Schwarz (Sandia National Laboratories)
Keywords: Telescopes, Instrumentation
Abstract:
As part of the AFRL-funded Near Earth Space Surveillance Initiative (NESSI) the University of New Mexico’s Measurement Astrophysics (MAP) Research Group has defined, designed and implemented several atmospheric measurement techniques to complement and supplement the observations of the CCD/Transit Instrument with Innovative Instrumentation (CTI-II). The principal idea driving the creation of atmospheric sensing and telescope metrology ancillary instrumentation is that these instruments produce data relevant to the reduction and analysis of astronomical data in the quest for quantitatively more precise and accurate photometric and astrometric observations of the night sky.
Instruments and techniques relevant to optical-infrared (OIR) space surveillance include:
” The Astronomical Lidar for Extinction (ALE) to measure precisely the time-dependent total atmospheric extinction
” A spectrophotometric telescope for measuring wavelength-dependent atmospheric extinction
” A differential microbarograph array to measure anomalous atmospheric refraction
” A multi-baseline microthermal array for measuring atmospheric turbulence on multiple spatial scales.
When implemented in support of the stationary, meridian-pointing CTI-II, designed to be the most precise ground-based photometric and astrometric telescope, these instruments operated together provide near real-time measurements of wavelength-dependent total atmospheric extinction caused by scattering and absorption by molecules and aerosols. They also characterize the time-dependent vertical atmospheric pressure and density above the telescope and measure the large-scale (degrees) tilt induced by atmospheric gravity waves, the apparent source of anomalous refraction.
Imaging, photometry and spectrophotometry of satellites can be dramatically enhanced by use of these low-cost deployable instruments. Applications relative to CTI-II will be described. The network of faint photometric and astrometric standard stars always observable in the northern hemisphere resulting from multi-year CTI-II observations and the utility of this network to sky surveys will be discussed and demonstrated.
Date of Conference: September 12-15, 2007
Track: Telescopes and Instrumentation