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1 of 2 Orbital Mechanics Academic Year 2017-2018 Lecturer: Camilla Colombo Exam 30 August 2018 Duration: 3 h All solution sheets have to be written in clear form in pen. On top of each sheet, please report in capital letters your surname, name and student number. In the solution of the exercise all the analytical and numerical procedure has to be reported. Please report the number of the answers from the text of the exercise. EXERCISE The return module of the Europa Lander mission is made of one stage (called Lift Off Module or LOM) and payload (the return capsule). After lift off the LOM detaches and the payload is released on a parking orbit around Europa with semi-major axis of 2200 km, at an altitude of 105 km from the Europa’s surface (Europa is one of Jupiter’s Moon). The gross mass (structure + propellant) of the LOM is 15 kg and the cost function (initial to payload mass ratio) of the module is 11. The specific impulse of the LOM is 220 s. Assume losses to be negligible on the dynamics of the return module. Find: 1. The mass ratio of the LOM 2. The initial mass at lift off, the mass of structure and propellant of the LOM, the mass of the return capsule The Europa Orbiter is instead at the apocentre of the return capsule’s orbit, at an altitude o f 1225 km above Europa’s surface. The orbiter is ahead of the return capsule on its orbit and maneuvers to phase with it after 25 phasing orbits. During the phasing manoeuvre the return capsule performs 25 revolutions of its orbit plus an additional fraction of its orbit. Assume impulsive maneuvers during phasing. Find: 3. The true anomaly of the return capsule at release 4. The cost and duration of the phasing maneuver After collecting the return capsule, the orbiter performs a single impulsive maneuver at the…