Exam 20210921 SOL

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1 of 4 Orbital Mechanics Academic Year 2020-2021 Lecturer: Camilla Colombo Exam 01 September 2021 Duration: 1.5 h All solution sheets must be written in clear form in pen. Do not write in pencil. 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 must be reported. Please report the number of the answers from the text of the exercise. Numerical results need to have proper units of measure. Last digit of Person Code (Codice Persona) 0 or 2 or 4 or 6 or 8 1 or 3 or 5 or 7 or 9 Exam Version 1 2 PART 1 Exercise 1 – Orbital manoeuvre A satellite performs a manoeuvre at the orbital position r around the Earth characterised by the orbital elements given in DATA. A manoeuvre is performed to exclusively rotate of an angle α [see DATA] the transversal component of the spacecraft velocity at the orbital position r. The rotation is performed positively around the +𝒓𝒓� direction. Data Earth data: 𝜇𝜇𝐸𝐸= 398600 km3/s2 𝑅𝑅𝐸𝐸= 6378.16 km Version Semi- major axis [km] Eccentricity Inclination [deg] RAAN [deg] Anomaly of perigee [deg] True anomaly [deg] α [deg] 1 -130000 1.1 40 30 50 10 3 2 -120000 1.2 30 40 35 20 4 1. Compute the transversal component of the velocity at point r before the manoeuvre. [Output in km/s with 2 decimal digits] 2. Compute the radial component of the velocity at point r before the manoeuvre. [Output in km/s with 2 decimal digits] 2 of 4 3. Is the shape of the orbit changed? 4. Compute the inclination of the orbit after the manoeuvre. [Output in degrees with 2 decimal digits] 5. Compute the right ascension of the ascending node after the manoeuvre. [Output in degrees with 2 decimal digits] 6. Compute the anomaly of perigee of the orbit after the…