Lessons learned in automatic operation of observatories for space debris observation

In the last years, the growing number of operative Italian’s satellites has triggered the necessity of a space debris observation facility. The first Italian’s observatory totally dedicated to space debris was the Spade observatory, developed at University of Rome La Sapienza and now located in Matera. To understand in depth the space debris environment it was needed to install another observatory for increasing the surveying capability, the EQUO observatory. The EQUO observatory, which is part of the ASI-Sapienza Agreement for the Broglio Space Center (BSC) in Malindi, Kenya, is an Equatorial Observatory, located at the BSC developed by Sapienza Space Systems and Space Surveillance Laboratory (S5Lab) research group. The project’s target is twofold. The primary goal is to detect and characterize space debris using optical methods. For a precise characterization of the space debris it is needed to calculate their position from raw optical images. Data are the input for the orbit determination phase that allow to calculate more accurate conjunction warnings due to realistic covariance and probability of collisions. The possibility of observe the same object from two different locations, one at mid latitudes and one at the Equator, increases the position determination accuracy. The secondary goal is the training of the Sapienza’s students, gaining experience in observatory automation procedures. The main efforts are in the selection of the best patterns and practices for fault tolerant systems to improve the system availability, that were used in designing the software for the EQUO project. The observatory is equipped with a 200 mm diameter f/4 optical tube in Newtonian configuration mounted on a motorized altazimuth mount. It uses a CCD sensor with a wide Field of View (FOV) of about 9 degrees squared. Everything is housed in a robotized dome and it is commanded by a rugged PC, selected to improve the overall system reliability in the equatorial humidity and relatively hot operation conditions. The final result is the realization of an automatic observatory able to remotely acquire space debris images from Italy. In this paper we discuss the design requirements of such a robotic observatory aimed to operate automatically, mainly focused on efficiency and robustness, and the lessons learnt during all the project phases from design to normal operation.