Evaluation of a demonstration telescope for the Pluto express mission

摘要

Abstract: The Ball Aerospace & Technologies Corporation and Southwest Research Institute have built a three mirror anastigmat telescope as a proof-of-concept, working model of the visible camera system for the highly integrated Pluto payload system (HIPPS) intended for use on the Pluto Express mission. This instrument is unique due to its small size, light weight (less than 2.5 kg) and bolt together design. The all aluminum construction allows the unit to operate over a wide temperature range. The system was designed to have a 5.8 by 0.2 degree field of view, 650 mm effective focal length, 75 mm diameter entrance pupil and a 26 micrometer spot size. The initial version of this telescope utilized diamond turned aluminum mirrors due to cost and schedule limitations. The scattering and imaging properties of this telescope were evaluated. A baffle system was designed and installed to reduce stray light in the system. To improve system performance, the mirrors were resurfaced with electroless nickel, diamond turned and post polished. The stray light performance of the system before and after resurfacing the optics is discussed. Future performance testing plans for this system are presented. !0