Ariadna Call for Ideas 2010: Active Removal of Space Debris
Type of activity: Standard study (25 k€)
Background and motivation
For more than half a century Earth orbits have been used for a wide variety of purposes and man-made objects, such as spacecraft, provide services that have become an integral part of our day-to-day lives. This rapidly growing population of space objects is increasing the risk of collisions and thus the loss of valuable assets and services.
The number of space objects has risen significantly. Currently there are less than 1000 active satellites in orbit, among more than 20 000 tracked objects (US SSN catalogue) and an estimated 600 000 fragments larger than 1 cm . These space debris consist of old or malfunctioning satellites, launcher stages and fragments of these. As demonstrated by the recent collision between Iridium-33 and Cosmos-2251, these hazards increase the overall risk of collision of space missions in an already harsh operating environment , as well as the overall operational costs (need of collision avoidance manoeuvres) .
Strategies for reducing the number of space debris (including intact, non-active objects) are internationally coordinated through the Inter-Agency Debris Coordination Committee (IADC) and implemented at various space agencies . Research is also ongoing to extend the understanding of the debris generation mechanisms leading to a range of measures aiming at avoiding the creation of further debris. These efforts are however not reducing the problem of debris already in orbit.
This Call for Ideas focuses therefore on active space debris removal techniques and concepts, which have received much less attention than debris mitigation considerations.
Current Active Space Debris Removal Concepts
Researchers and engineers devised many concepts for active space debris removal [7-14]. Many of the concepts found in the literature are however lacking technological readiness. For instance, some are still at the stage of the initial idea that needs to be nurtured to more promising and feasible concepts. The relatively little attention given to this topic has resulted in an opportunity to propose creative new ideas, to mature existing ones further and to create the need for a more comprehensive comparison and classification.
Currently described ideas and concepts for active debris removal can be classified into the following categories:
Each concept has its own preferred orbital regime (LEO, MEO, GEO), and only targets specific debris size ranges. As an example, Melamed et al provide an assessment of concepts for debris removal in GEO . It puts emphasis on a few criteria including practicality, cost and risk.
For the purpose of this study, the most hazardous debris are considered those with a size larger than 10 cm. These can cause catastrophic spacecraft break-ups, and they represent also the tracking capability limit for current radar with regard to debris in LEO orbits.
The proposed reference scenario for the study is:
Research and Study Objectives
The main aim of this Call for Ideas is to perform research on new and innovative scientific and technical concepts for active space debris removal.
For the selected concepts or techniques, the first most important research step shall be performed during the study.
In principle, all scientific fields of potential relevance are encouraged to propose solutions, which should not be restricted to the classical spacecraft engineering and mission analysis research communities.
Technically, study proposals shall therefore contain in addition to the general idea:
Proposers are invited to also provide additional information related to aspects such as reliability, re-usability of the concept and removal operation duration.
Proposers are strongly encouraged to underline their reasoning with references to published papers and research results.