Fringe visibility errors resulting from dual object imaging for stellar interferometers

Abstract

Practical stellar interferometry for space domain awareness is challenged by the relative motions of orbital objects and telescope arrays that require array phasing using guide stars. An orbital object’s image sensitivity to the location and brightness of the guide star is problematic, possibly resulting in a degraded resolution or loss of image content when both objects fall within the interferometer’s field of view. We characterized an orbital object’s visibility using visibility contrast to noise ratios ( C N R Δ v ) as a performance metric for orbital object image quality. Experimental validations included orbital object visibility measurements for dual binary pinholes that were scaled in size and brightness individually to match expected interferometer data collection scenarios. We show agreement in C N R Δ v results, indicating resolvable orbital object signals during periods of collection when signal contributions from both the orbital object and guide star are present. Expanding presented results to imaging interferometers, we discuss how dual object imaging could degrade performance under the scenarios examined.

Evaluating sparse aperture imaging performance: simulation and experiment

“…AFRL utilizes a large 2.54m diameter, F/6 collimator that has been described previously [6,7]. A range of coherent and incoherent sources in the visible and short to long-wave infrared are available for illuminating pinholes, bar targets and scenes placed on a small optical table at the injection port of the collimator.…”