The TANDEM Project as a Pilot Case for Wide-field Telescope Arrays

Abstract We give here an account of the Telescope Array eNabling DEbris Monitoring (TANDEM) project, an innovative concept aimed at flanking, on a shared piggyback mount, the main G. D. Cassini 152 cm f /8 telescope at the INAF-OAS observing premises in Loiano, Italy. The system is especially intended for space situational awareness activities related to the study of asteroids and comets and on the astrodynamical characterization of circumterrestrial space debris and artificial satellites. TANDEM consists of a combination of four customized and independently steerable 35 cm f /3 Newtonian telescopes, each equipped with a Moravian C4-16000 camera, observing through the BVR c I c filters of the Johnson–Cousins system. The camera carries on board a GSense 4040 (4096 × 4096 pixels) monochrome CMOS detector with an electronic shutter and a 9 μ m pixel size. A corrected field of view of 2° × 2° is offered by each telescope, though quite special pointing capabilities and observing modes are available for the telescope array, such as to cover up to 16 deg 2 across sparse celestial fields, each up to 20° in separation. While especially conceived for observing activities in the framework of the European Consortium for Space Surveillance and Tracking, TANDEM may also find additional applications in a more direct astronomical context, as we briefly outline along this review.