The rapidly expanding space sector is at the forefront of innovation. New technologies are been continuously developed to allow more availability of space for a multitude of commercial or scientific goals. The same is especially true for the field of Space propulsion, where the focus is towards more compact and greener solutions, for launchers, satellites and landers. One of the most suitable candidates for chemical propulsion is the use of liquid oxygen in combination with liquid hydrogen, which, however, comes with many drawbacks connected primarily to the low energetic density of liquid hydrogen and the complexity of storing cryogenics. An innovative solution to this challenge comes with the use of Metal oxidation or metal combustion reaction. This implies the use of the reaction between air and metals or between water and metals to generate heat, power and hydrogen. This allows for much easier power generation since metal powders are simple to stock and have a much higher density than hydrogen. Therefore, the process is compact and completely renewable. The technology has undoubted potential for space applications too. The high energy density, the lack of cryogenics, the high availability and the re-usability make this technology suitable for power generation purposes and, in this case, for propulsive purposes. This thesis aims to explore the various applications of metal combustion, with a particular focus on space propulsion applications. The gathered literature will be then used to produce a conceptual design of a novel propulsion system which maximises the benefits of metal combustion.

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One idea to stop the increasing threat of global warming is to build a space sunshade, made up of a constellation of satellites to reflect a portion of the sunlight. These satellites need to reach an equilibrium point where they can stay in orbit with minimal adjustments. A few feasibility studies have been made in this area and the location of the equilibrium point, L1' has been found. An area that is still unclear is the best way of getting the satellites to L1'. One idea is to use electric propulsion engines , and utilizing a gravity assist around the Moon on the way to L1'. Gravity assists have mostly been performed with chemical rocket engines, so doing it with electric propulsion causes some unique issues. The goal was to find a trajectory including the gravity assist showing that this could be an effective way of transporting the satellites. To measure how effective this would be, a trajectory without a gravity assist was also created as a means of comparison. The trajectory and orbit simulations were done in the program General Missions Analysis Tool (GMAT), and the resulting trajectory took 51 days and used 83.4kg of fuel for a fuel-to-mass-ratio of 21.5%. This was a worse result compared to the trajectory without a gravity assist, which only used 80.4kg of fuel. Finally a discussion around a potential trajectory which was shown to have a much greater velocity increase was had, which would indicate that a gravity assist maneuver could provide a trajectory that does save on fuel compared to using no gravity assist.

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Thesis. 1977. M.S.--Massachusetts Institute of Technology. Dept. of Earth and Planetary Sciences. / Microfiche copy available in Archives and Science. / Bibliography : leaves 72-73. / M.S.

The following study is interested in questions of diversity and inclusiveness in Marissa Meyer's Lunar Chronicles, a tetralogy of best-selling young adult fairy tale revisions comprised of Cinder (2012), Scarlet (2013), Cress (2014), and Winter (2015). Scholars have expended significant energy defining the fairy tale, tracing its history and development, and analyzing 20th-century adult fairy tale revisions informed by second-wave feminism. However, little scholarly attention has been paid to young adult fairy tale revisions of the 21st Century and less still on The Lunar Chronicles. This study begins the work of filling that gap. Through a close reading of The Lunar Chronicles, I argue that Meyer's tetralogy is an influential, complex, and thematically comprehensive example of an ongoing shift away from feminist fairy tale revisions for adults toward young adult fairy tale revisions that focus on diversity and inclusiveness. My project begins with a chapter situating Meyer's work in the context of existing fairy tale scholarship and the burgeoning emphasis on diversity in contemporary American culture and young adult publishing. The following three chapters provide, respectively, a close reading of The Lunar Chronicles focused on racial identity, gender and sexuality, and disabilities. In showcasing more recent YA fairy tale retellings, the final chapter seeks to draw some tentative conclusions about the continuing importance of diversity and inclusiveness in an evolving genre of reimagined fairy tales for a young adult audience. / Master of Arts / In her bestselling young adult science fiction tetralogy The Lunar Chronicles (2012-2015), Marissa Meyers reimagines four classic fairy tales: "Cinderella" (Cinder), "Little Red Riding Hood" (Scarlet), "Rapunzel" (Cress), and "Snow White" (Winter). Meyer's work continues a tradition of revising traditional fairy tales. Disney's Princess franchise of reimagined fairy tales has essentially defined the genre for generations of American children, while Angela Carter's adult fairy tale revisions challenged its patriarchal orientation in the wake of second-wave feminism. In my detailed textual analysis of The Lunar Chronicles, I argue that Meyer's tetralogy is a relatively early, influential, and comprehensive example of a developing wave of specifically young adult fairy tale retellings that reflects a growing focus on issues of diversity and inclusiveness in 21st-century America. My project begins with a chapter that places Meyer's work in historical context, focusing on the development and definition of the fairy tale and presenting a brief overview of previous approaches to fairy tale revision. In the next three chapters, I analyze The Lunar Chronicles as it complicates questions of, respectively, race, gender and sexuality, and disability. My project concludes with a brief overview of young adult fairy tale retellings of the last decade, exploring how the genre continues to engage with questions of diversity and inclusiveness.