The faculty of Aerospace Engineering at Delft University of Technology is one of the world's largest faculties devoted entirely to aerospace engineering. In the Netherlands it is the only research and education institute directly related to the aerospace engineering sector. It covers the whole spectrum of aerospace engineering subjects. In aeronautics, the faculty covers subjects ranging from aerodynamics and flight propulsion to structures and materials and from control and simulation to air transport and operations. In astronautics, topics include astrodynamics, space missions and space systems engineering. The faculty has around 2,500 BSc and MSc students, 214 PhD candidates and 27 professors supported by scientific staff. The faculty's mission is to be the best Aerospace Engineering faculty in the world, inspiring and educating students through modern education techniques and enabling staff to perform ambitious research of the highest quality for the future of aerospace. The working atmosphere at the faculty is friendly, open-minded and dedicated. The Department of Space Engineering provides premier European education and research in space engineering. The Department consists of two research groups: Astrodynamics and Space Missions, and Space Systems Engineering. It runs an integrated research programme comprising miniaturisation, distributed space systems, mission analysis and orbits, space propulsion, ascent and re-entry, and planetary exploration. The Department operates a cleanroom facility for the design, integration, and verification of satellite assemblies up to entire satellites. The Astrodynamics and Space Missions (A&S) section is dedicated to the modelling and analysis of satellite orbits, planetary missions and their many planetary applications. For more information, please visit www.as.lr.tudelft.nl. Job description Accelerometers on the CHAMP, GRACE and GOCE satellites have enabled the production of high resolution thermosphere density data. The observations have provided detailed information on forcing by solar EUV radiation and charged particles, and have revealed for the first time the extent of thermosphere forcing by processes in lower layers of the atmosphere. Because most of this research has focused on relative changes, scale differences between the data sets have been largely ignored. These scale differences originate from errors in the aerodynamic modelling, specifically in the modelling of the gas-surface interaction and of the satellite outer surface geometry. The aim of this project is to consolidate the data sets from these satellites and the new Swarm satellites. This will be accomplished by improving the satellite aerodynamic modelling, making use of detailed 3D drawings to represent the satellite geometry. The uncertainty in gas-surface interaction parameters will be reduced in an estimation procedure using the acceleration data, taking advantage of simultaneous aerodynamic interactions (drag, lift, moments), analysed during variations in satellite orientation, and of simultaneous observations by multiple satellites. The outcome of this work will help to improve our understanding of the energy balance of the atmosphere. Resolving the problem of deriving the true absolute thermosphere density scale from satellite dynamics measurements can also significantly improve orbit predictions, including long-term predictions of the space debris population. Requirements Applicants are expected to have a university degree (MSc) in physics, applied mathematics, earth and planetary sciences, geodesy or a related area, with a strong background in numerical modelling. Experience in working with large satellite data sets and/or an affinity for upper atmospheric research would be assets. Applicants must be proficient in spoken and written English. The successful candidate will be granted a temporary employment contract with the university for a period of 4 years (48 months), with an evaluation at the end of the first year. Within the contract period, the candidate is expected to produce a dissertation (PhD thesis) of sufficient quality for him/her to be awarded a PhD. Conditions of employment TU Delft offers an attractive benefits package, including a flexible work week and the option of assembling a customised compensation and benefits package (the 'IKA'). Salary and benefits are in accordance with the Collective Labour Agreement for Dutch Universities. As a PhD candidate you will be enrolled in the TU Delft Graduate School. TU Delft Graduate School provides an inspiring research environment; an excellent team of supervisors, academic staff and a mentor; and a Doctoral Education Programme aimed at developing your transferable, discipline-related and research skills. Please visit www.phd.tudelft.nl for more information. Information and application For more information about this position, please contact E. N. Doornbos, phone: +31 (0)15-2785870, e-mail: e.n.doornbos@tudelft.nl. To apply, please send your CV, a statement of purpose, a list of courses in your BSc and MSc programmes including marks, a list of published papers or reports, the names and addresses of two references and a letter of application. Please e-mail your application by 1 April 2015 to Mrs. R. van Wingaarden, n.vanwingaarden@tudelft.nl. When applying for this position, please refer to vacancy number LR15-04. http://recruitment2.tudelft.nl/vacatures/index.php?lang=en&id=542944&type=w Application Deadline : 1 April 2015