Prioritized observation strategy for fragmentation debris clouds using Lambert solutions and breakup model-based heat map

Kurzfassung

The continuous growth in the number of Resident Space Objects (RSOs) in Earth orbit represents a critical challenge for spacecraft safety and long-term space sustainability. Fragmentation events, whether caused by collisions or explosions, can suddenly generate debris clouds composed of a large number of fragments, posing an immediate threat to operational satellites. In this context, ground-based optical telescopes play a key role thanks to their flexibility, fast re-tasking capability, and ability to support coordinated observation campaigns across multiple stations. In such operational scenarios, the primary objective is to rapidly support the planning of ground-based optical observations by identifying where telescopes should be pointed in order to maximise the detection of fragments within limited visibility windows. The proposed methodology employs the NASA Standard Breakup Model (SBM) to generate synthetic debris clouds and associated fragment velocity distributions. Since the SBM inherently relies on stochastic processes when assigning fragment physical characteristics and ejection speeds, a single model run cannot provide statistically representative results. To address this limitation, a Monte Carlo approach is implemented to generate multiple equally probable fragment distributions, which are then combined to obtain a robust representation of the expected cloud dispersion. The generated fragments are initially propagated under Keplerian dynamics to characterize their short-term evolution and to evaluate their potential visibility from the SMARTnet optical telescope network operated by the German Aerospace Center (DLR). During the first visibility window, a Lambert-based approach is applied within a three-dimensional right ascension–declination-range domain to estimate the maximum spatial extent of the debris cloud. After this initial characterization, the cloud is propagated forward in time including the dominant orbital perturbations for the considered regime. Updated observation windows are then computed. This analysis is performed in the topocentric reference frame of each observing station, allowing the simultaneous management of multiple telescopes within a coordinated network. Within this framework, the propagated fragment distributions are superimposed onto the Lambert-derived cloud to identify regions with the highest fragment density. These highpriority regions represent optimal observation targets, and their corresponding right ascension and declination coordinates are extracted to provide telescope pointing directions, improving the number of detected fragments within limited observation time. The methodology has been tested on a real GEO fragmentation case, namely the breakup of LUCH (OLYMP-K 1) (NORAD: 40258), successfully demonstrating its capability to support observation planning and enabling the recovery of a large number of tracklets.