Date MARSIS 2nd Boom Deployment
7 June 2005
Following in-depth analyses performed after the deployment of the first MARSIS antenna boom on board Mars Express, ESA has decided to proceed with the deployment of the second 20-metre antenna boom.The full operation will be performed during a time frame starting 13 June and nominally ending on 21 June.
A delay in the execution of the second boom deployment was necessary, due to problems encountered with the first deployment in early May this year. During the deployment, one of the antenna hinges (the tenth) got stuck in an unlocked position. Analysis of data obtained from earlier ground testing suggested a potential solution.
The Mars Express spacecraft control team at ESA’s Spacecraft Operations Centre (ESOC) succeeded in unblocking the hinge by exposing the cold side of the boom to the Sun. This warmed the hinges and the boom quickly became unstuck. In the end, the first boom deployment was completed on 10 May.
The lessons learnt during the first boom deployment were used to run new simulations and determine a new deployment scenario for the second boom. This scenario contains an additional sun-heating phase, to get the best possible thermal conditions for all hinges.