ERS-2 platform disposal operations

Abstract

ERS marked in many ways Earth observation at the European Space Agency. When ERS-1 was launched in 1991, it was one of the most sophisticated spacecraft ever built in Europe. It accomplished, together with its successor ERS-2, a major scientific mission covering a period of more than 20 years. During this extended period, the mission had to respond to new requirements while the actual capabilities of the ERS-2 spacecraft were declining. At the end of the mission, the mitigation of space debris had become a priority and posed a final challenge. Disposal operations were prepared to lower the orbit and to "passivate" the ageing spacecraft. The development and the execution of these operations are presented with a particular emphasis on the influence of the platform design and of its status at the time of execution. In order to give an overview of the platform status at the beginning of the disposal phase, its design is presented together with a short in-flight history of major failures and on-board software modifications. The ability of the spacecraft to comply with space debris mitigation recommendations is then analyzed before the development and the execution of the disposal operations is described in detail. © 2012 by European Space Agency.