Historical accounts depict NASA's interactions with American citizens beyond government agencies and aerospace firms since the 1950s and 1960s as efforts to 'sell' its human space flight initiatives and to position external publics as would-be observers, consumers, and supporters of such activities. Characterizing citizens solely as celebrants of NASA's successes, however, masks the myriad publics, engagement modes, and influences that comprised NASA's efforts to forge connections between human space flight and citizens after Apollo 11 culminated. While corroborating the premise that NASA constantly seeks public and political approval for its costly human space programs, I argue that maintaining legitimacy in light of shifting social attitudes, political priorities, and divided interest in space flight required NASA to reconsider how to serve and engage external publics vis-à-vis its next major human space program, the Space Shuttle. Adopting a sociotechnical imaginary featuring the Shuttle as a versatile technology that promised something for everyone, NASA sought to engage citizens with the Shuttle in ways appealing to their varied, expressed interests and became dependent on some publics' direct involvement to render the vehicle viable economically, socially, and politically. NASA's ability and willingness to democratize the Shuttle proved difficult to sustain, however, as concerns evolved following the Challenger accident among NASA personnel, political officials, and external publics about the Shuttle's purpose, value, safety, and propriety. Mapping the publics and engagement modes NASA regarded as crucial to the Shuttle's legitimacy, this case study exposes the visions of public accountability and other influences -- including changing perceptions of a technology -- that can govern how technoscientific institutions perceive and engage various external publics. Doing so illuminates the prospects and challenges associated with democratizing decisions and uses for space and, perhaps, other technologies managed by U.S. government agencies while suggesting a new pathway for scholarly inquiry regarding interactions between technoscientific institutions and external publics. Expanding NASA's historical narrative, this study demonstrates that entities not typically recognized as space program contributors played significant roles in shaping the Shuttle program, substantively and culturally. Conceptualizing and valuing external publics in these ways may prove key for NASA to sustain human space flight going forward. / Ph. D.

The Virginia Tech Equilibrium Chemistry (VTEC) code is a keyboard interactive, user friendly, chemical equilibrium solver for use on a personal computer. The code is particularly suitable for a teaching / learning environment. For a set of reactants at a defined thermodynamic state given by a user, the program will select all species in the JANAF thermochemical database which could exist in the products. The program will then calculate equilibrium composition, flame temperature, and other thermodynamic properties for many common cases. Examples in this thesis show VTEC's ability to predict chemical equilibrium compositions and flame temperature for selected reactions, and demonstrate how VTEC can substitute for and aid in the design of lab experiments, and identify trends in parametric studies. The 1976 NASA Lewis Chemical Equilibrium Code (CEC76) from which VTEC has been adapted uses Lagrangian multipliers to minimize free energy. CEC76 was written for mainframe computer use. Later versions of CEC76, adapted for personal computer use are available for a fee and have a very minimal user interface. / Master of Science

In 2023, the U.S. House of Representatives, newly under Republican control, sought to limit federal spending, creating a potentially dangerous situation for American space exploration and NASA. Given the budget situation, it may be beneficial for NASA to look to its existing geographic footprint for areas of deeper support to provide elected leaders with an electoral justification to support NASA missions. The areas with the greatest chance of generating support for NASA are spaceports due to the rocket launches they support serving as focusing events for NASA. Rather than focusing as past scholars have on specific regions, this research examines driving distance from the Kennedy Space Center to provide more detail about the possible relationship between geographic proximity to spaceports and views of NASA. To test for the existence of this proximal relationship and the impact of viewing rocket launches on opinions of NASA, the study fielded an original online survey to gather U.S. residents' opinions about NASA, as well as information on where they lived and on how frequently they view rocket launches. Employing bivariate and multivariate regression models, the responses were analyzed to explore the relationship between geographic proximity to the primary spaceport and exposure to rocket launches on respondents' reported views of NASA. This study found that as respondents' distance from the Kennedy Space Center increased, positive views of NASA decreased. Additionally, respondents who viewed the launch of NASA's Space Launch System (SLS) rocket had more positive views of the agency than others. Overall, these results indicate that direct exposure to NASA activities, facilitated either by living near the Kennedy Space Center or by viewing the SLS launch is associated with more positive perceptions of NASA. The hypothesis that rocket launches can impact views of space exploration was supported based on analyses of reported online and in-person viewership that suggested notable relationships with opinions of commercial launch providers. Yet, even though the models found support for this relationship, they suggested that other factors likely are also important to fully understanding the relationship. NASA's future public engagement strategies evidently should focus on narrowing the awareness gap of NASA activities for those further away from spaceports and do not have direct exposure to the agency. / Master of Arts / In 2023, the U.S. House of Representatives, newly under Republican control, sought to limit federal spending, creating a potentially dangerous situation for American space exploration and NASA. Given the budget situation, it may be beneficial for NASA to look to its existing geographic footprint for areas of deeper support to provide elected leaders with an electoral justification to support NASA missions. The areas with the greatest chance of generating support for NASA are spaceports due to the rocket launches they support serving as potential advertisements for NASA. Rather than focusing as past scholars have on specific regions, this research examines driving distance from the Kennedy Space Center to provide more detail about the possible relationship between geographic proximity to spaceports and views of NASA. Additionally, given that the impact of rocket launches on support for NASA has not been measured this study can help quantify support for NASA's most visible public events. To test for the existence of this relationship and the impact of viewing rocket launches on opinions of NASA, the study fielded an original online survey to gather U.S. residents' opinions about NASA, as well as information on where they lived and on how frequently they view rocket launches. Regression analyses are used to determine the impact of distance from the Kennedy Space Center and different modes of viewership of rocket launches on opinions of NASA. This study found that as respondents' distance from the Kennedy Space Center increased positive views of NASA decreased. Additionally, respondents who viewed the launch of NASA's Space Launch System (SLS) rocket had more positive views of the agency. Overall, these results indicate that direct exposure to NASA activities facilitated either by living near the Kennedy Space Center or by viewing the SLS launch can increase positive perceptions of NASA. NASA's future public engagement strategies evidently should focus on narrowing the awareness gap of NASA activities for those further away from spaceports and do not have direct exposure to the agency.

This thesis examines the growth of the space elevator community in America from 1975 to 2010. It argues that the continued practical failures of the space elevator, a proposed technology for efficiently transporting payloads and people into space without conventional propulsion sources, resulted from a technological paradigm built around the rocket and supported by a traditional engineering culture. After its triumph in landing men on the Moon from 1969 to 1972, the United States' National Aeronautics and Space Administration (NASA) sought to advance novel concepts for further space exploration, but it fumbled in pursuing nontraditional notions of escaping the atmosphere such as the space elevator. Employing interviews with space elevator advocates Bradley Edwards and Michael Laine and other primary and secondary sources, this thesis also draws on concepts such as technological paradigms, engineering cultures, and the technological sublime. It concludes by demonstrating how success eluded the marginalized space elevator researchers who found themselves grappling with the vast social and technical system that supported the rocket's hegemony. / Master of Arts / This thesis examines the growth of the space elevator community in America from 1975 to 2010. It argues that the continued practical failures of the space elevator, a proposed technology for efficiently transporting payloads and people into space without conventional propulsion sources, resulted from a technological paradigm built around the rocket and supported by a traditional engineering culture. The technological paradigm of the rocket encompassed all of the people and practices that made the rocket work. After its triumph in landing men on the Moon from 1969 to 1972, the United States' National Aeronautics and Space Administration (NASA) sought to advance novel concepts for further space exploration, but it fumbled in pursuing nontraditional notions of escaping the atmosphere such as the space elevator. Much of this failure is owed to an engineering culture within NASA that looked down upon challenging the rocket. This thesis demonstrates how success eluded the marginalized space elevator researchers who found themselves grappling with the vast social and technical system that supported the rocket's hegemony.

No description available.

This thesis aims to investigate whether additive manufacturing is applicable in manufacturing the 1N thruster option that Bradford Ecaps offers. Therefore, the nozzle design is of particular interest as AM provides accessibilities to manufacturing complex structures. The current Ecaps 1N thruster has an operating thrust lifespan that exceeds the required lifespan commonly needed for the majority of customers. With AM, an increase in production throughput and optimization of nozzle design is possible. A candidate material, a platinum group metal, was picked for a future 1N thruster prototype concerning the limiting operating constraints. Computational fluid analysis was performed to investigate different contour nozzles to investigate the possibility of improving the performance of the Bradford ECAPS 1N thruster. AMATLAB code was developed to model the contour nozzles, and ANSYS Fluent was used for the computational analysis. Three different nozzle geometries were evaluated to investigate the overall performance of the expanding exhaust gas and thrust properties in vacuum conditions. Configuration 1. which had an extended nozzle was selected as a solution since it eliminatedthe interferences with the continuum. The Nasa CEA code was used to generate the fluid gas properties. No substantial performance gain was observed for the 1N thruster. This was found to be due to the boundary-dominated flow exhibited in the nozzle. A conical nozzle was found to work comparatively well. / Detta examensarbete syftar till att undersöka om additiv tillverkning (AM) är tillämplig vid tillverkning av Bradford Ecaps 1N raketmotor. Därför är munstycksdesignen av särskilt intresse eftersom AM ger möjlighet för tillverkning av komplexa strukturer. Den nuvarande Ecaps 1N-motorn har en livslängd som överstiger den livslängd som krävs för de flesta kunder. Med AM är ökning av produktionsgenomströmningen och optimering av munstycksdesign möjlig. Ett kandidatmaterial, en metall i platinagruppen, valdes ut för en framtida 1N prototyp med hänvisning till de begränsande driftsbegränsningarna. Beräkningsflödesanalys utfördes för att undersöka olika konturmunstycken för att undersöka möjligheten till att förbättra prestandan hos Bradford ECAPS 1N framdrivningssystem. En MATLAB-kod utvecklades för att modellera konturmunstyckena och ANSYS Fluent användes för beräkningsanalysen. Tre olika munstycksgeometrier utvärderades för att undersöka den totala prestandan hos de expanderande avgaserna och dragkraftsegenskaperna under vakuumförhållanden. Konfiguration 1. som hade ett förlängt munstycke valdes som en lösning eftersom detta eliminerade interferenserna med kontinuumet. Nasa CEA-koden användes för att generera fluidens gasegenskaper. Ingen betydande prestandaökning observerades för 1N motorn. Detta visade sig bero på det gränsskiktsdominerade flödet som uppvisades i munstycket. Ett koniskt munstycke visade sig fungera relativt bra.

No description available.

International Telemetering Conference Proceedings / October 25-28, 1993 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The Hubble Space Telescope (HST) Observatory Management System (HSTOMS), located at the Goddard Space Flight Center (GSFC), provides telemetry, command, analysis and mission planning functions in support of the HST spacecraft. The Telemetry and Command System (TAC) is an aging system that performs National Aeronautics and Space Administration (NASA) Communications (Nascom) block and telemetry processing functions. Future maintainability is of concern because of the criticality of this system element. HSTOMS has embarked on replacing the TAC by using functional elements developed by the Microelectronics Systems Branch of the GSFC. This project, known as the Transportable TAC (TTAC) because of its inherent flexibility, is addressing challenges that have resulted from applying recent technological advances into an existing operational environment. Besides presenting a brief overview of the original TAC and the new TTAC, this paper also describes the challenges faced and the approach to overcoming them.

A visualization of the NASA Deep Space Network activity. Implemented in an interactive 3D environment. A thesis work by students from the Media technology and engineering program at Linköping University.

The space vehicle system concept (i.e. resupply vehicle) described is based on the new direction that President George W. Bush announced on January 14, 2004 for NASA’s Human Exploration, which has the space shuttle retiring in 2011 following the completion of the International Space Station (ISS). This leads to a problem for the ISS community regarding the capability of meeting a sixty metric-ton cargo shortfall in resupply and the ability of returning large payloads, experiment racks and any other items too large to fit into a crew only type spacecraft like the Orion or Soyuz. NASA and the ISS partners have realized these future problems and started developing various systems for resupply to ISS, but none offer the capability for large up or down mass close to that of the shuttle. Without this capability, the primary purpose behind the ISS science mission is defeated and the ability to keep the station functioning properly is at risk with limited payload delivery (i.e. replacement hardware size and mass). There is a solution to this problem and a majority of the solution has already been designed, built, and flight tested. Another portion has been studied heavily by a team at NASA for use in a slightly different mission. Following the retirement of the space shuttle fleet and the loss of heavy up and down mass capability, the only solution to the problem is to design a new spacecraft. However, the budget and new direction for NASA will not allow for a costly new payload carrying spacecraft. The solution is to use existing commercial off the shelf (COTS) hardware to minimize the costs of developing a totally new system. This paper will discuss the technical feasibility of this conceptual configuration.