Michael Hart, HartSCI LLC; Stephen Warner, HartSCI LLC; David Irwin, Hart Scientific Consulting International LLC; Jeff Hagen, Hart Scientific Consulting International LLC; Adam Schilperoort, Hart Scientific Consulting International LLC; Christopher Warner, Hart Scientific Consulting International LLC; David Tousley, HartSCI LLC; Johanan Codona, HartSCI, LLC;
Keywords: adaptive optics, telescopes, imaging, atmospheric turbulence, space domain awareness
Abstract:
Adaptive optics (AO) as a tool to enhance imaging performance is now ubiquitous on large telescopes, both for astronomy and space domain awareness (SDA). By reducing the blur induced by atmospheric turbulence, images are substantially sharpened. Image contrast and sensitivity to faint sources are also improved by the concentration of energy into a smaller solid angle in the focal plane. These performance enhancements are of direct benefit in supporting SDA objectives such as the detection and tracking of closely-spaced objects, improved fidelity in images of resolved objects, and detection of faint objects against a bright background.
Historically, AO systems have been expensive. For that reason they are generally confined to large telescopes, and each one is a unique design. But substantial cost reductions in critical components have recently been realized, such as deformable mirrors, fast cameras with low read noise for wavefront sensing, and high-speed computing. These advances have allowed the development of standardized AO system designs at a cost that makes them attractive for operators of smaller telescopes in the one meter class where the performance enhancement, while not as dramatic as on larger telescopes, is still of great value. The key quantity here is D/r0, where D is the aperture diameter and r0 is the Fried length or atmospheric coherence scale. The larger this ratio, the more AO has to offer. The particular value, then, is at shorter wavelengths in the visible and near infrared, where r0 is smaller than the bands typically addressed by AO.
AO is a core corporate capability of HartSCI. In this paper, we report on AO systems designed and deployed by the company to telescopes in the 0.7 – 1 m size range at two sites in Arizona and one in New Mexico. The sites include the Fred Lawrence Whipple Observatory, on Mt. Hopkins, AZ at a telescope operated by the Miniature Exoplanet Radial Velocity Array (MINERVA), an astronomical consortium led by Harvard University; the Naval Precision Optical Interferometer (NPOI) on Anderson Mesa outside Flagstaff, AZ; and the Starfire Optical Range (SOR) operated by the Air Force Research Laboratory (AFRL), Kirtland AFB, NM. We present results and AO performance measurements from the three sites which span a range of atmospheric seeing conditions, object type and brightness. We put these results in the context of the expanded SDA objectives that can be addressed by telescopes of comparable size at sites around the world equipped with cost-effective AO systems.
Date of Conference: September 27-20, 2022
Track: Optical Systems & Instrumentation