The quest for establishing a human presence and development beyond the Earth, especially on the moon has opened up opportunities for future plans for lunar bases and settlements. However, the cost of using resources outside the lunar environment can inhibit this form of expansion, therefore the need for In Situ Resource Utilization (ISRU). The aim of this research was to investigate the possible usage of in situ resources for lunar construction and other economic development. The study evaluated different methods of material preparation using lunar regolith simulant for structural applications on the moon. The research employed the use of the regolith simulant known as Black Point-1 (BP-1). This research work presents the methodology used in developing lunar simulant and compares the properties of BP-1 regolith simulant to those of lunar soil, in terms of geotechnical and mechanical properties. Various laboratory analyses were carried out to determine these properties with the aid of thermal and analysis, particle size distribution, and XRD experiments. Our findings show that the particle size distribution and porosity of BP-1 are similar to that of the lunar regolith. The simulant was then sieved to produce four grades of powder (38 µmm, 106 µm, 212 µm and unsieved). The graded powders were then compressed to form a series of disc-shaped green compacts for sintering. The sintered samples were then subjected to compression testing. There were four different values of average compressive strength of the porosity materials ranging from lowest to highest porosity corresponding to the smallest to largest average grain sizes of 38 µm, 106 µm, unsieved and 212µm and they were 66.14MPa, 60.47MPa, 58.52MPa, 42.74 MPa, respectively. The particle size distribution was investigated on Black Point-1 simulant to determine the effect of the porosity while the bulk properties of the material were also examined for each of the four porosity grades, and this includes toughness, Poisson ratio, bulk modulus, Young’s modulus of elasticity and compressive strength. When compared with other ISRU structural materials and published data for real lunar regolith it was observed that sintered BP-1 is sufficiently strong for lunar structural applications.

Oil pipeline spills in the Niger Delta cause a great deal of environmental damage to sensitive ecosystems and losses of many millions of dollars to the Nigerian economy every year. These spills occur along the routes of pipeline infrastructure and other oil facilities like flowlines, trunk lines, flow stations, barges, well heads etc. The causes of these spill events include: operational or maintenance error, ageing oil facilities, as well as acts of deliberate sabotage of the pipeline equipment which often result in explosions and fire outbreaks. In this project, we have investigated whether satellite observations could be used to detect these oil pipeline fires. The Nigerian National Oil Spill Detection and Response Agency (NOSDRA) database contains a total of 10 072 oil spill reports from 2007 to 2015. The space-based approach we considered in this dissertation included the use of data gathered by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra and Aqua satellites, which recorded 85 129 active fire hotspots in the Niger Delta from 2007 to 2015. Since the oil spill reports serve as validation data for these oil spill fires, we explored the capability of the MODIS instrument to study the spatio-temporal correlation between spills and fire events by attempting to investigate whether the largest spills by volume that resulted in fires could be detected from space in near-real time. Although the NOSDRA oil spill reports are plagued with several irregularities from the Joint Investigation Visits by the joint task force who visit spill sites, our approach in this dissertation automated the filtering process of the raw database to meet our research goal and objective. This study confirms that, indeed, fires resulting from oil spills are detectable using the MODIS fire products. For 43 of the largest spill events, we were able to establish a spatio-temporal correlation of spill incident reports with MODIS fires clearly associated with the oil pipeline infrastructure. Our study also shed light on the spatial and temporal characteristics of non-pipeline fires in the study area.

Active spacecraft attitude control by using a pumped fluid as the inertial mass has potential advantages over reaction wheels, including high torque, lower power consumption, reduced jitter and prolonged lifetime. Previous work addressed conceptual and mission-specific control aspects, and one fluid loop has flown on a demonstration mission. In this dissertation, a parametric sizing model is developed that can optimize a fluid loop for any mission, based on pump capabilities and customer requirements. The model can be applied to circular, square and helical fluid loops, and includes the power consumption due to viscous friction. A configurable prototype was developed to verify the model, as well as a spherical air bearing to verify the rotational aspects of the various fluid loop configurations. The model was applied to various hypothetical missions. In conclusion, the fluid loop has the fundamental potential to replace reaction wheels in a wide variety of satellites above approximately 20 kg, if mass is carefully optimized and efforts are made to develop a suitable pump. This is considered worthwhile, as the actuator comes with many potential advantages.

The Dream Chaser is a space vehicle currently under development by the Sierra Nevada Corporation for purposes of carrying humans and cargo to low Earth orbit. In 2016, the United Nations entered into an agreement with Sierra Nevada Corporation to fly experimental payloads on the Dream Chaser. The collaborative UNOOSA-SNC Dream Chaser mission will be approximately two to three weeks in duration, with the Dream Chaser orbiting Earth at an altitude of 500 km with an inclination of 0 − 35◦ . This will be the first space mission dedicated to attaining the Sustainable Development Goals. In this investigation the South African space and aerospace industry is placed under the microscope for the purpose of studying the feasibility of landing the Dream Chaser Space Vehicle on South African soil. The research dictates possibly having to establish a dualuse airport/spaceport recognised by the South African Space Council under supportive legislation to support this mission. Elements addressed in this investigation range from physical facilities such as the airports, workshops and laboratories through Dream Chaser specific requirements and specifications, right down to space and civil aviation regulations. This dissertation will assess all available infrastructure and supporting entities that will facilitate the safe landing of the Dream Chaser space vehicle in South Africa. However site visits and interviews were not part of this investigation. This investigation prefaces the University of Cape Town's Space Lab plans to submit a landing proposal for a possible alternative landing site(s) for the Dream Chaser outside of the USA. This report is the first major step in researching and documenting the potential for landing the Dream Chaser or any reusable space vehicle in South Africa and will therefore make the case for South Africa as a suitable and attractive landing destination, not just for the Dream Chaser, but for accompanying scientists and researchers from all over the world involved in the mission.

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