Speaker
Description
The evaluation of the environmental impact of a mission can be extended to consider not only aspects such as resources depletion and toxicity, but also its impact on the space environment and, in particular, the potential contribution of a mission to the creation of new space debris objects. The approach described in this work is based on a risk indicator that quantifies which is the probability of an object to be involved in a fragmentation and which would be the severity of such an event, considering the resulting increase in the collision probability for operational satellites. The index is computed along the whole mission profile in order to take into account whether disposal strategies are implemented and the reliability of such strategies.
A self-standing index, in the frame of life cycle assessment or with a specific use such as ranking ADR targets, can only serve as an actionable metric if it can be placed in the broader context. This includes the space environment of a whole as well as shifting from single object to mission such as constellations, including launchers. As the index proposed here relies on high-level mission parameters (e.g. operational orbit, mass, disposal strategy), it can be evaluated early in the mission design phase and it allows, for example, different design choices (e.g. operating altitude) to be compared. This leads to using the index as a metric of how the environment capacity is consumed, indicating with this term the set of space objects and missions that are compatible with a stable evolution of the environment. It will be shown how long term simulations of the environment can be used to define a threshold value of the cumulative index across the whole environment. Finally, a capacity allocation scheme, similar to the frequency one regulated by ITU, will be outlined and examined considering the actual launch traffic and compliance to mitigation guidelines observed in the last years.
