Intern in the Ground Systems Engineering and Innovation Department, Flight Dynamics Division

The position is opened in the Earth Observation support section within the Flight Dynamics Division, which provides Flight Dynamics Engineering and Operations support to the Earth Observation fleet operated by ESOC, including ESA’s Earth Explorer program and EU’s Copernicus program.

The Flight Dynamics support consists of study, development, test, operations, evaluation, and maintenance activities, addressing infrastructure and project-specific issues. This is provided by a multi-mission team involved from early phases of the missions, such as early studies, to the last moment, like re-entry operations.

Candidates interested are encouraged to visit the ESA website: http://www.esa.int

Field(s) of activity for the internship

Internship topic: Characterization of air drag modelling errors and orbit prediction accuracy

The spacecraft fleet operated at ESOC includes satellites from the Earth Explorers family and the Copernicus programme. Among its responsibilities, the Flight Dynamics Earth Observation Team performs the operational orbit determination for these missions. This process involves estimating the satellite’s state vector along with a set of parameters associated with dynamic models used in the propagation. Most of our Earth Observation missions operate at orbital altitudes where atmospheric drag is an important perturbation. This force is a function, among other factors, of the atmospheric density, a reference area, and the aerodynamic drag coefficient; the latter is estimated in the orbit determination process to fit the aerodynamic force during the analysed time interval. This estimation, however, has the tendency to absorb errors associated with the air drag models.

Years of flight dynamics operations have yielded valuable historical data on the estimated air drag force. This data comes from satellites operated at different altitudes and orientations of the orbital plane, and it reveals patterns which could help improve our current air drag models. Since the air drag force is the largest source of error, the ultimate benefit of this characterisation is an improvement of our orbit propagation accuracy, as well as the mission end of life predictions.

• The project proposed for this intership involves studying our current air drag model, in combination with the historic estimated data, to better understand its deficiencies, propose corrections, and improve the orbit prediction accuracy. The program of activities proposed for the project can be broken down as follows:
• familiarization with the OPS-GFE infrastructure, including GODOT and GENEOS.
• familiarization with the orbit determination process.
• elaborate an atmospheric density map, as a function of different parameters (position, season, space weather).
• compare the air drag computed from our models versus the historic data, and identify potential enhancements to our models.
• study the orbit prediction accuracy for a full range of orbit altitudes, orbital plane orientations, ballistic coefficients, and space weather conditions.

• Behavioural competencies
• Result Orientation
• Operational Efficiency
• Fostering Cooperation
• Relationship Management
• Continuous Improvement
• Forward Thinking
• For more information, please refer to ESA Core Behavioural Competencies guidebook
• Education
• You must be a university student, preferably studying at master’s level. In addition, you must be able to prove that you will be enrolled at your University for the entire duration of the internship.
• Additional requirements
• The working languages of the Agency are English and French. A good knowledge of one of these is required. Knowledge of another ESA Member State language is an asset.
• During the interview, your motivation for applying to this role will be explored.