Horizontal wind influence on satellite aerodynamics at the edge of space

To be able to understand and predict space weather better, global in-situ satellite measurements are needed at an altitude of 100-150 km. However, due to the high density, space weather induced winds and the lack of data, it is a challenge to design a satellite mission to that region. Therefore, in this thesis, the influence of horizontal wind...

An interactive, web-based, near-Earth orbit visualization tool

Even though several orbit visualization tools exist, the ability to compare multiple satellite orbits or manipulate time are not readily available with the current tools. Furthermore, most other visualization tools require additional effort or installations to work properly. To address these issues with other tools an interactive, web-based,...

GOCE Spacecraft Attitude Control: A magnetic attitude controller simulator

Given the difficulty that is normally associated with tuning highly nonlinear control systems, such as seen in LEO spacecraft, it is interesting to evaluate how new controller types perform. The measured data from the GOCE mission has led to the creation of high fidelity torque models describing the angular perturbations acting on a spacecraft....

Orbital Lifetime Predictions: An assessment of model-based ballistic coefficient estimations and adjustment for temporal drag coefficient variations

The ballistic coefficient β of a satellite indicates the influence atmospheric drag has on the orbital decay of said satellite. The method developed in this study estimates the ballistic coefficients of 1U CubeSats by analysing both its historical TLE data and the density it experienced along its trajectory according to the empirical density...

Determination of the attitude state of space debris objects based on Satellite Laser Ranging, using Envisat as a test case

The attitude state of the passive Envisat satellite (ESA) has been estimated before using various techniques like Satellite Laser Ranging, radar and using light-curves. This research focusses on the use of Satellite Laser Ranging. Due to the relatively large (meter scale) offset between the center-of-mass of the satellite and the reflector where...

Exploration of optimal orbits in the strongly perturbed environment of the 2001 SN263 triple asteroid system

For the past 20 years, the small bodies of the solar system, such as asteroids and comets, have been increasingly gathering the interest of scientists and space agencies. The latter have been multiplying the number of space missions to study them. Brazil does not want to be left out and has been working on its own mission, ASTER, which has the...