Paolo Ferri concludes his unique and personal view of the ground-breaking ESA Rosetta mission based on his two decades-long association with the pioneering ESA space mission. In the fourth in his series of exclusive articles for ROOM, he recalls the challenging and unexpected events after Rosetta’s arrival at Comet 67P/Churyumov-Gerasimenko, the first ever deployment of a lander on a comet’s surface, and the mission’s final spectacular conclusion.
The long years of hibernation, out of contact with Rosetta, were spent completing the preparation for the comet phase of the mission, defining operations concepts, designing and testing software tools and procedures, hiring and training the newcomers in the flight control team. Never before in the history of space exploration had a space probe reached a comet and tried to orbit around it.
The flight dynamics and overall flight operations challenges were huge: we had to gradually approach the target comet, and then try and fly around it while building up our knowledge of the nucleus and its dynamical environment. Our Flight Dynamics colleagues had prepared a model of the comet, including its mass, shape and the dynamical forces that would act on our spacecraft, and integrated it into the orbit determination software. However, the model could only be built up and refined by using the Rosetta spacecraft itself as a ‘sensor’ of the dynamic perturbations. It was an iterative process that could only start when we were in proximity of the nucleus: it was like learning to fly by doing it!
Read the conclusion of Paolo Ferri's fascinating account of the Rosetta mission, up to and including the completion of the mission on Comet 67P/Churyumov-Gerasimenko in the full version of the article, available now to our subscribers.