Fast recovery mode for micro-meteoroid impacts: A LISA mission study

Abstract

This article studies and provides a plausible solution to address the effects of micro-particle impacts on the LISA mission. The influence of these undesired events are analysed using a set of 8 worst-case impact conditions from an ESA database of more than 200,000 impacts that captures the anticipated micro-meteoroid environment that the LISA spacecraft may encounter in a span of its envisioned 6.5 years of mission. Based on the results of this analysis, a novel operational mode called SCIHOLD is proposed to provide fast recovery from micro-meteoroid impacts. The performance of the SCIHOLD mode is validated using a LISA high-fidelity, non-linear simulator in two steps. Firstly, the identified 8 worst-case impacts are evaluated in nominal and dispersed conditions in a Monte Carlo campaign, and secondly, larger impacts beyond the ones in the database are simulated to assess the recovery limits of the proposed recovery mode. The results show that the proposed operational mode is successful in recovering the LISA spacecraft from the impacts, and most importantly, that this is achieved with a mean overall recovery time of 92.5s, a considerable reduction compared to a full re-acquisition scenario typically lasting hours.