Martin Ploner, ASA Astrosysteme GmbH; Philipp Keller, ASA Astrosysteme GmbH; Egon Döberl, ASA Astrosysteme GmbH ; Wolfgang Promper, ASA Astrosysteme GmbH; Dietmar Weinzinger, ASA Astrosysteme GmbH
Keywords: fast wide field telescope, space debris observation, robotic telescope
Abstract:
Nowadays the detection of space debris becomes more and more important due to the rapidly rising number of such particles. Currently about 20000 artificial objects are tracked routinely with various observation techniques. Collisions with space debris are a considerable risk for all kinds of spacecrafts. Optical observations are the preferred method for the search of artificial (man-made) particles in higher orbits and for the search of natural (meteoroid) particles. For the scanning of a large area of the sky within a short time optical systems with a small focal ratio are best suited for this task. Such fast systems suffer often from a poor image quality, especially at the edges of the image. A new optical design for a telescope with a diameter of the primary mirror of 300 mm and a focal ratio lower than 1.5 guarantees excellent spot sizes for the whole field of view with a diameter of 60 mm. For the recording of the observation time a new developed eventtimer is used. In combination with an image sensor with electronic shutter like an interline sensor an accuracy for the epoch registration better than 100 microseconds can be achieved. The optical system is assembled on a mount with direct drive technology which enables the precise tracking of objects in all orbital regimes. A weather module which provides information about the ambient atmospheric conditions and the cloud coverage completes the system. The software package provides the possibility for autonomous operation without any interaction of an operator. As soon as the weather and lighting conditions are below the user defined limits, predefined actions like opening the dome, cooling down the camera, opening the mirror covers and switching on the fans will be carried out before the observations are started. An autofocus module completes the system. Thanks to the tube built from carbon the effect of variation of temperature on the focus is quite small. A built-in scheduler provides the possibility for automatic scheduling of a list of predefined targets and calibration images. A more sophisticated observation scenario can be prepared by the operator himself by writing a xml document containing all relevant settings for each individual target. This document will be sent to the telescope system by establishing a network connection and can be modified at any time during the observations. The images together with all relevant informations are stored in the FITS format. Every clear night thousands of images can be acquired with the system. An image tool chain for the processing of the images is currently in development. The goal is to achieve an astrometric accuracy of a few tens of an arc second even for fast moving objects, the processing will be carried out in near real time. This enables the rescheduling of objects which cannot be correlated with any catalogue within the same night for improving the orbit.
Date of Conference: September 17-20, 2019
Track: Optical Systems & Instrumentation