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Christopher A Jones

Publications and source records attributed to Christopher A Jones.

14 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2019

Cost Breakeven Analysis of Lunar ISRU for Human Lunar Surface Architectures

The return of humans to the lunar surface encompasses a range of possible architectures from brief Apollo-like sorties to long-term sustainment of human presence. Any architecture in this span requires propellant for the crew’s ascent from the lunar surface, as well as consumables to support their presence on the Moon. Oxygen and hydrogen are candidates for the propellant for the ascent vehicle due to their high specific impulse and potential for production from lunar resources and also constitute important consumables for the crew. Thus, the production of oxygen and/or hydrogen from lunar resources could significantly reduce the mass that must be sent from Earth to enable future human lunar missions. To assess the merits of using lunar resources, the costs associated with developing, producing, launching, operating, and maintaining those systems must be considered relative to the costs of delivering the needed resources from Earth. The demand for those resources depends upon the nature of the lunar mission, while the costs of both Earth-derived and lunar-derived resources depend on the performance requirements and technology capabilities associated with each approach. Thus, determining which approach is more cost efficient requires modeling the performance and cost of the associated systems as well as the range of possible architectures over which such a determination might apply. This research proposes a model that parametrically captures the factors influencing the relevant costs of providing propellant and crew consumables on the lunar surface from Earth and from the Moon. Two ISRU system models are assessed relative to propellant delivery from Earth. In this model, lunar ISRU breaks even with propellant delivery from Earth at high propellant demands and mission durations with multi-year ISRU system lifetimes; however, the costs of developing the necessary technologies to support a highly reliable and autonomous lunar ISRU system were not included.

ISRU↗
NASA NTRS2018

Mega-Drivers to Inform NASA Space Technology Strategic Planning

The National Aeronautics and Space Administration (NASA) Space Technology Mission Directorate (STMD) has been developing a new Strategic Framework to guide investment prioritization and communication of STMD strategic goals to stakeholders. STMD’s analysis of global trends identified four overarching drivers which are anticipated to shape the needs of civilian space research for years to come. These Mega-Drivers form the foundation of the Strategic Framework. The Increasing Access Mega-Driver reflects the increase in the availability of launch options, more capable propulsion systems, access to planetary surfaces, and the introduction of new platforms to enable exploration, science, and commercial activities. Accelerating Pace of Discovery reflects the exploration of more remote and challenging destinations, drives increased demand for improved abilities to communicate and process large datasets. The Democratization of Space reflects the broadening participation in the space industry, from governments to private investors to citizens. Growing Utilization of Space reflects space market diversification and growth. This paper will further describe the observable trends that inform each of these Mega Drivers, as well as the interrelationships between them within STMD’s new Strategic Framework.

Melanie L Grande↗
NASA NTRS2018

Strategic Framework for NASA’s Space Technology Mission Directorate

In October 2016, NASA’s Space Technology Mission Directorate (STMD) began adopting a new strategic framework that focuses investment prioritization and communication on impacts, outcomes, and challenges. The structure of the framework has been modeled after one successfully pioneered by NASA’s Aeronautics Research Mission Directorate over the past five years, incorporating lessons learned and changes where appropriate. The Framework is driven by two major factors: (a) dialogue with the community and (b) analysis of the overarching trends shaping the course of civilian space research. These factors are captured in the Framework as Mega-Drivers, which represent major axes of change within the space industry and are characterized by a collection of industry trends and projections. In response to these Mega-Drivers, STMD has developed its understanding of the vision for the future of civilian space relative to STMD space research, captured in five Strategic Thrusts that represent the major lines of investment within STMD’s portfolio. Within each of these Strategic Thrusts, multiple measurable, community-level goals have been established that STMD chooses to pursue as part of a joint effort across the community. STMD chose these goals based upon their potential impact, refers to them as Outcomes within the Framework. These outcomes are decomposed into the products and/or capabilities that will be delivered by STMD, represented in the framework as Technical Challenges. This paper will further describe the framework structure and the progress that has been in defining each of the above elements to date.

Kevin D Earle↗
NASA NTRSDate not supplied

Feasibility Study of a Carbon Dioxide Breathing, Solid-Fueled Ramjet for Martian Descent and Landing of Human Class Payloads

This study analyzes the cross-range capabilities of solid-fueled ramjets in a Martian atmosphere for applications in entry, descent, and landing. Trajectories and engine operability are characterized using Mach and dynamic pressure operational points. It is predicted that use of atmosphere-breathing propulsion will enable access to additional surface latitudes without the need for orbital plane changes. Development of an integrated design environment facilitates preliminary ramjet design and analysis, and enables sensitivity studies to identify high impact areas of technology development. In addition, additive manufacturing supports prototyping, rapid ground testing, and allows for utilization of complex geometries.

Shi Broadwell↗
NASA NTRSDate not supplied

Visualizations to Aid Decision-Making in the ACCP Value Framework

NASA’s priorities for Earth Science are informed by the 2017-2027 Decadal Survey for Earth Science and Applications from Space of the National Academies of Sciences, Engineering and Medicine. In that document, five Designated Observables are identified as priorities for research, two of which are Aerosols, and Clouds, Convection, and Precipitation. NASA is addressing these two Designated Observables by a combined study (the Aerosols, Clouds, Convection, and Precipitation, or ACCP, study). In this context of the ACCP study’s multiple objectives and multiple stakeholders, heuristic-based approaches are insufficient to assess candidate observing system concepts due to the complexity of the decision problem. For the ACCP study, this complexity in assessment is such that absent a structured approach that permits understanding of the steps leading to a decision, the decision risks being made on an incomplete basis. While prose and numeric data both have their place in effective communication, visualizations play an important part not only in presenting information, but also in structuring conversations around that information. Each of the visualizations developed for the ACCP Value Framework serve at least one of several functions: it structures communication about a method or process, it facilitates the elicitation and aggregation of data, or it summarizes complex information to enable analysis. Thus, these visualizations can present information, structure conversations, or do both.

Christopher A Jones↗
NASA NTRSDate not supplied

Cost Breakeven Analysis of Lunar In-Situ Propellant Production for Human Missions to the Moon and Mars

NASA is preparing to return humans to the lunar surface as a first step to a human exploration campaign of Mars. Both a sustained lunar campaign and a campaign of missions to Mars will require tens to hundreds of tonnes of propellant. Although this propellant could be delivered from Earth, an alternative approach is to use the potentially vast quantities of lunar ice to enable in-situ propellant production on the lunar surface. This study evaluates the cost breakeven for using lunar-derived propellants, as opposed to those delivered from Earth, in support of an extended human exploration campaign with both a multi-year presence on the Moon as well as multiple crewed missions to Mars. In so doing, the value of lunar propellant production is considered in the context of future exploration priorities, addressing the question: over what range of human missions to the lunar surface and Mars does in-situ propellant production trade favorably with propellant delivery from Earth on the basis of cost? The results of this analysis show that the magnitude and duration of the lunar campaign, more so than the Mars campaign, drive the breakeven and that without long lifetime ISRU systems, with greater than 5 years of autonomous operation before replacement, the demand in cis-lunar space for a Mars campaign favors propellant delivery from Earth.

Christopher A Jones↗
NASA NTRSDate not supplied

Integrated Trajectory, Habitat, and Logistics Analysis and Trade Study for Human Mars Missions

Environmental Control and Life Support System (ECLSS) architecture selection has profound implications for mission cost and mass extending far beyond the ECLSS itself. Similarly, other mission architecture decisions – particularly involving transportation systems – can influence optimal ECLSS architectures. Loop closure influences requirements for water, oxygen, and other consumables. System maintainability and reliability influences spares mass and risk. System, consumables, and spares mass interact with transportation system architectures and propellant demands and propulsion element sizing. All these interactions with other systems must be considered when evaluating ECLSS options. Analyses that focus only on maximizing ECLSS loop closure – or minimizing ECLSS mass, or minimizing ECLSS life cycle cost – may lead to sub-optimal or even counterproductive system architecture and investment decisions at the mission level. For example, an ECLSS architecture that minimizes ECLSS life cycle cost but results in excessively high logistics mass could lead to significantly increased transportation system costs or make interplanetary transportation infeasible. Increased loop closure could result in higher development costs and higher mass if system/spares mass increases outweigh consumables reduction. In addition, systems mass and consumables mass are not directly comparable and have different impacts on propellant requirements, as consumables mass changes over the course of the mission. This paper presents an integrated analysis examining the overall impact of different ECLSS and transportation architectures on mass for a crewed Mars mission, including the habitat and transportation systems as well as consumables, spares, and propellant. Key observations are discussed, along with opportunities for further sensitivity analysis and model development. Overall, ECLSS development activities must consider their impacts at the mission level, as part of an integrated system, rather than in isolation.

Mars↗
NASA NTRSDate not supplied

Integrated Trajectory, Habitat, and Logistics Analysis and Trade Study for Human Mars Missions

Environmental Control and Life Support System (ECLSS) architecture selection has profound implications for mission cost and mass extending far beyond the ECLSS itself. Similarly, other mission architecture decisions – particularly involving transportation systems – can influence optimal ECLSS architectures. Loop closure influences requirements for water, oxygen, and other consumables. System maintainability and reliability influences spares mass and risk. System, consumables, and spares mass interact with transportation system architectures, including propellant demands and propulsion element sizing. All these interactions with other systems must be considered when evaluating ECLSS options. Analyses that focus only on maximizing ECLSS loop closure – or minimizing ECLSS mass, or minimizing ECLSS life cycle cost – may lead to sub-optimal or even counterproductive system architecture and investment decisions at the mission level. For example, an ECLSS architecture that minimizes ECLSS life cycle cost but results in excessively high logistics mass could lead to significantly increased transportation system costs or make interplanetary transportation infeasible. Increased loop closure could result in higher development costs and higher mass if system/spares mass increases outweigh consumables reduction. In addition, systems mass and consumables mass are not directly comparable and have different impacts on propellant requirements, as consumables mass changes over the course of the mission. This paper presents an integrated analysis examining the overall impact of different ECLSS and transportation architectures on Earth departure mass for a crewed Mars mission, including the habitat and transportation systems as well as consumables, spares, and propellant. Key observations are discussed, along with opportunities for further sensitivity analysis and model development. Overall, ECLSS development activities must consider their impacts at the mission level, as part of an integrated system, rather than in isolation.

Mars↗
NASA NTRSDate not supplied

Visualizations to Aid Decision-Making in the ACCP Value Framework

The Aerosols, Clouds, Convection, and Precipitation Value Framework is used to introduce structure, transparency, and traceability into the decision-making process for a study formulating and assessing potential observing system concepts to respond to the 2017-2027 Decadal Survey for Earth Science and Applications. Within the Value Framework, visualizations play an important role in presenting information and structuring conversations around that information. This paper describes three guiding principles that were applied to the design of the visualizations of the Value Framework, presents examples of visualizations that serve at least one of several functions (structuring communication, facilitating elicitation and aggregation of data, and summarizing complex information), and identifies lessons learned from the development and implementation of those visualizations. The guiding principles and lessons learned have not only contributed to the success of the Value Framework and the ACCP study, but also can be applied in other decision-making activities.

Christopher A Jones↗
NASA NTRSDate not supplied

Recommendations to Advance Space Trusted Autonomy

While the various space agencies of the U.S. federal government have distinctly different visions for future operational space systems, all share important foundational commonalities: improve mission performance, reduce mission costs, incorporate technology advances more rapidly, increase reliability and resiliency, reduce risk, and adapt to anomalies and environmental hazards. These common needs, combined with the maturation of autonomous technology and the prospect of leveraging autonomous systems to address these needs, have led each agency to consider how and when to implement increasing levels of autonomy in their space systems. Simultaneously, the related question of how to determine the trustworthiness of an autonomous system is also escalating in significance.

Christopher A Jones↗
NASA NTRSDate not supplied

Recommendations to Advance Space Trusted Autonomy

The interagency Space Science and Technology Partnership Forum was established in2015 to identify synergistic efforts and technologies across the U.S. government. While the various space agencies of the U.S. government have distinctly different visions for future operational space systems, all share important foundational common needs. These needs, combined with the maturation of autonomous technology and the prospect of leveraging autonomous systems to address those needs, have led each agency to consider how and when to to implement increasing levels of autonomy in their space systems, and how to determine the trustworthiness of an autonomous system. The Partnership facilitated dialogue among the partners, collected and analyzed data on current and desired future levels of capability, and identified gaps to motivate three recommendations that can be addressed within the Partnership community. These recommendations address the need for more robust documenting and socializing of anomalies in space system operations; the need to expand communication and trust within the community of developers, operators, and end users; and the need for a safe development and testing environment for maturing and demonstrating future autonomous space systems. These recommendations will facilitate both near-term programmatic actions and long-term steps for implementing enduring progress towards enabling space trusted autonomy.

Christopher A Jones↗
NASA NTRSDate not supplied

Integrated Crewed Mars Mission Analysis, Part II: The Trajectory Strikes Back

Crewed missions to Mars present a challenging problem involving strong interactions between a variety of spacecraft systems. Design and architecture decisions made by one system can have powerful implications for another. Siloed subsystem development and optimization efforts are unlikely to generate optimal results for the integrated system and may lead to counterproductive investments at the mission and system level. Mismatched assumptions between different subsystems can also negatively impact the final result. Integrated systems analysis, trade studies, and sensitivity analysis are a critical element of successful Mars mission design. Previous work examined the linkages between Environmental Control and Life Support System (ECLSS) loop closure, food water content, spares Probability of Sufficiency (POS), and other factors by performing an integrated mass and cost assessment of a variety of Mars habitat and transportation system designs. This paper expands upon that work by evaluating the impact of mission duration, trajectory, and propulsion technology alongside key habitat variables. Transportation system and trajectory design decisions have enormous impacts on overall system mass, and the impacts of those decisions are themselves sensitive to the mass of the habitat that is being transported. This paper examines a variety of mission cases and evaluates total departure mass for each case. An estimate of relative costs for specific cases is also provided. The results are discussed, with an emphasis on the sensitivity of mass, cost, and other figures of merit to key parameters. Interactions and dependencies between various decisions, particularly those that relate to technology investments, are also highlighted. Overall, the various elements, systems, and subsystems required to support human spaceflight should not be optimized and evaluated in isolation, but instead should be analyzed as part of an integrated system. This paper demonstrates how integrated analysis can improve system understanding and lead to more optimal and effective crewed exploration systems.

Human Spaceflight↗