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1 of 2 Orbital Mechanics Academic Year 2017-2018 Lecturer: Camilla Colombo Exam 12 February 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. [Assume linked-conics approach where relevant] EXERCISE A spacecraft is orbiting Titan (Saturn’s moon) at an altitude of 1200 km, on a circular orbit. The spacecraft releases a scientific package to land on Titan’s surface. The total mass of the spacecraft before release is 840 kg. After release, the spacecraft performs a maneuver to accelerate in the direction of its orbital velocity and escape Titan’s attraction with a zero C3 excess energy. Both circular and escape orbits lie on the equatorial plane of Titan. During the maneuver, the spacecraft burns 125 kg of propellant, with a specific impulse of 210 s. Assume drag losses to be negligible. Find: 1. The cost of the escape maneuver 2. The mass of the scientific package released 3. The v provided by the same amount of propellant in case of non -detachment of the scientific package After escape, the spacecraft performs a Hohmann maneuver to reach the orbit of Rhea (Saturn’s moon). Consider both Titan and R hea on circular orbits around Saturn, with i=0° with respect to Saturn’s equator. After the Hohmann transfer, the spacecraft is behind Rhea with a =13°. The spacecraft is designed to perform a phasing maneuver to rendezvous with Rhea after 2 orbits. Find: 4. The cost and duration of the Hohmann maneuver 5. The cost and duration of the phasing maneuver 2 of 2 Before arrival at Rhea, a…