Vincent Morand, CNES; Joao Alves, EU SatCen; Johannes Gelhaus, DLR; Simon Georges, DSTL; Jose Maria Hermoso, CDTI; Elena Vellutini, ASI
Keywords: System studies, GEO, MEO, SSA, Telescopes, EUSST, Optical network
Abstract:
The Decision of the European Parliament and the Council Establishing a Space Surveillance and Tracking Support Framework was adopted on April 16th 2014. It has established the SST Support Framework with the general objective to contribute to ensuring the long-term availability of European and national space infrastructure, facilities and services, providing support to the actions aimed to establish a SST capability at European level and with an appropriate level of European autonomy. The specific objectives of the SST Support Framework are to assess and reduce the risk to in-orbit operations of European spacecraft from collisions, to reduce the risks related to the launch of European spacecraft, to survey uncontrolled re-entries of space objects into the Earths atmosphere and to seek the prevention of proliferation of space debris.
To attain these objectives, the SST Consortium, which today is built by the participating Member States (France, Germany, Italy, Spain and United Kingdom) in coordination with the European Union Satellite Center (SatCen), operates a network of Member State ground-based sensors, to survey and track space objects and to produce a database thereof, and derived information. Finally, SST services (i.e. collision avoidance, re-entry analysis and fragmentation analysis) are provided to different users (i.e. Member States, Council, Commission, EEAS, public and private spacecraft owners and operators, public authorities concerned with civil protection) via the EUSST Service Provision Portal. The initial services started in July 2016 and from this date continuous improvements are being made. As of 2017, a pool of more than 15 telescopes, 5 radars and 4 lasers are operated within EUSST.
This paper deals with the present and future performance assessment through extensive simulation of the optical part of this network of sensors. First, individual sensors performances and corresponding surveillance strategies are modelled and simulated to estimate the whole system performance in terms of coverage capability with respect to the reference MASTER 2040 population in MEO and GEO. The whole reference population above a given size is propagated over several days and detection of objects is assessed depending on their magnitude. The improvement of performance due to the inclusion of new sensors is also analyzed. This assessment of the current capabilities of the system allows us to identify the gaps between the current network and a future one that would allow a high autonomy for MEO and GEO observation of 35cm and bigger objects.
Then, a working methodology is followed in order to design, starting from the existing network, several architecture options that match the specifications. Starting from a list of candidate sites suitable for optical observation and spread all over the world, a selection is performed to ensure a given level of redundancy to cope with unavailability from different sources (failure, weather, etc.). Then, several telescopes designs are analyzed with the idea to have great detection capability (high limiting magnitude) as well as great coverage capability (high search rate). Surveillance strategies are built to maximize the use of such sensors for detection and cataloguing of space objects. Cataloguing simulations, to estimate the size and precision of the catalogue that can be built, as well as the inclusion of tracking sensors, using a tasker and a scheduler to optimize their use, is also envisaged. The analysis is conducted both for GEO and MEO orbits and the corresponding difficulties are discussed. The paper will present in detail the working methods followed as well as some of the numerical results obtained.
Date of Conference: September 11-14, 2018
Track: Poster