Risk aspects of a mission to a comet

• Published in: Proceedings of the Institution of Mechanical Engineers. Part G, Journal of aerospace engineering Vol. 212; no. 3; pp. 149 - 155
• Main Author: Turner, R F
• Format: Journal Article
• Language: English
• Published: London, England SAGE Publications 01.01.1998; SAGE PUBLICATIONS, INC
• Subjects: Failure analysis; Risk assessment; Rockets; Space probes; nucleus; space; European Space Agency (ESA); comet; launcher; Rosetta
• DOI: 10.1243/0954410981532216
• ISSN: 0954-4100

Space science missions are rarely a repeat of a predecessor and thus in the wider view they do not have the benefit of heritage-related statistics. This paper discusses the cost and risk factors in gaining access to space and describes the challenges of the forthcoming Rosetta mission, which has the objective of conducting studies of a comet and its increasing activity as it moves towards the sun. It will fly in formation with the nucleus and later send a lander to its surface to conduct in situ measurements. Reference will be made to the further challenges for the scientific instruments faced by an eight-year period of inactivity during the cruise phase after launch. Statistics have a part to play at the component and unit test levels but are increasingly less relevant at instrument, spacecraft and mission levels. Ultimately the designer is faced with a string of single-point failure possibilities, commencing with the launch vehicle and culminating with the unknown surface conditions that will greet the lander.