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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 73 records · Page 4
All sourcesNASA NTRSDOE OSTI
NASA NTRS1997

Evaluation of Lunar Dark Mantle Deposits as Key to Future Human Missions

I proposed to continue detailed mapping, analysis and assessment of the lunar pyroclastic dark mantle deposits in support of the Human Exploration and Development of Space (HEDS) initiative. Specifically: (1) I continued gathering data via the Internet and mailable media, and a variety of other digital lunar images including; high resolution digital images of the new Apollo masters from JSC, images from Clementine and Galileo, and recent telescopic images from Hawaii; (2) continued analyses on these images using sophisticated hardware and software at JSC and the College of Charleston to determine and map composition using returned sample data for calibration; (3) worked closely with Dr. David McKay and others at JSC to relate sample data to image data using laboratory spectra from JSC and Brown University; (4) mapped the extent, thickness, and composition of important dark mantle deposits in selected study areas; and (5) began composing a geographically referenced database of lunar pyroclastic materials in the Apollo 17 area. The results have been used to identify and evaluate several candidate landing sites in dark mantle terrains. Additional work spawned from this effort includes the development of an educational CD-Rom on exploring the Moon: Contact Light. Throughout the whole process I have been in contact with the JSC HEDS personnel.

Coombs, Cassandra↗
NASA NTRS2005

Human Mission to Europa and Titan - Why Not? Executive Summary

Outline a step-by-step Development Plan of the key barriers and their solutions to enable human exploration of the outer solar system. Secondary: Perform a case study which supports and emphasizes the key elements of the Development Plan.

Finarelli, Margaret G.↗
NASA NTRS2017

Entry, Descent, and Landing Guidance and Control Approaches to Satisfy Mars Human Mission Landing Criteria

Precision landing on Mars is a challenge. All Mars lander missions prior to the 2012 Mars Science Laboratory (MSL) had landing location uncertainty ellipses on the order of hundreds of kilometers. Sending humans to the surface of Mars will likely require multiple landers delivered in close proximity, which will in turn require orders of magnitude improvement in landing accuracy. MSL was the first Mars mission to use an Apollo-derived bank angle guidance to reduce the size of the landing ellipse. It utilized commanded bank angle magnitude to control total range and bank angle reversals to control cross range. A shortcoming of this bank angle guidance is that the open loop phase of flight created by use of bank reversals increases targeting errors. This paper presents a comparison of entry, descent and landing performance for a vehicle with a low lift-to-drag ratio using both bank angle control and an alternative guidance called Direct Force Control (DFC). DFC eliminates the open loop flight errors by directly controlling two forces independently, lift and side force. This permits independent control of down range and cross range. Performance results, evaluated using the Program to Optimize Simulated Trajectories (POST2), including propellant use and landing accuracy, are presented.

Dwyer Cianciolo, Alicia↗
NASA NTRS2011

Long Duration Space Missions: Human Subsystem Risks and Requirements

This viewgraph presentation reviews the human health and performance risks associated with long duration space flight beyond low earth orbit. The contents include: 1) Human Research Program; 2) Human Subsystem Risks; 3) Human Exploration Framework Team (HEFT) Architecture Elements; 4) Potentially Unacceptable Risks -1; 5) Potentially Unacceptable Risks-2; and 6) Major Mission Drivers of Risk.

Kundrot, Criag E.↗
NASA NTRS2014

International Human Mission to Mars: Analyzing A Conceptual Launch and Assembly Campaign

In July of 2013, U.S. Congressman Kennedy (D-Mass.) successfully offered an amendment to H.R. 2687, the National Aeronautics and Space Administration Authorization Act of 2013. "International Participation—The President should invite the United States partners in the International Space Station program and other nations, as appropriate, to participate in an international initiative under the leadership of the United States to achieve the goal of successfully conducting a crewed mission to the surface of Mars." This paper presents a concept for an international campaign to launch and assemble a crewed Mars Transfer Vehicle. NASA’s “Human Exploration of Mars: Design Reference Architecture 5.0” (DRA 5.0) was used as the point of departure for this concept. DRA 5.0 assumed that the launch and assembly campaign would be conducted using NASA launch vehicles. The concept presented utilizes a mixed fleet of NASA Space Launch System (SLS), U.S. commercial and international launch vehicles to accomplish the launch and assembly campaign. This concept has the benefit of potentially reducing the campaign duration. However, the additional complexity of the campaign must also be considered. The reliability of the launch and assembly campaign utilizing SLS launches augmented with commercial and international launch vehicles is analyzed and compared using discrete event simulation.

Cates, Grant↗
NASA NTRS2016

Research Objectives for Human Missions in the Proving Ground of Cis-Lunar Space

Beginning in as early as 2023, crewed missions beyond low Earth orbit will begin enabled by the new capabilities of the SLS and Orion vehicles. This will initiate the "Proving Ground" phase of human exploration with Mars as an ultimate destination. The primary goal of the Proving Ground is to demonstrate the capability of suitably long duration spaceflight without need of continuous support from Earth, i.e. become Earth Independent. A major component of the Proving Ground phase is to conduct research activities aimed at accomplishing major objectives selected from a wide variety of disciplines including but not limited to: Astronomy, Heliophysics, Fundamental Physics, Planetary Science, Earth Science, Human Systems, Fundamental Space Biology, Microgravity, and In A major component of the Proving Ground phase is to conduct research activities aimed at accomplishing major objectives selected from a wide variety of disciplines including but not limited to: Astronomy, Heliophysics, Fundamental Physics, Planetary Science, Earth Science, Human Systems, Fundamental Space Biology, Microgravity, and In Situ Resource Utilization. Mapping and prioritizing the most important objectives from these disciplines will provide a strong foundation for establishing the architecture to be utilized in the Proving Ground.

Niles, P. B.↗
NASA NTRS2015

Physiological Health Challenges for Human Missions to Mars

During the next decades, manned space missions are expected to be aiming at the Lagrange points, near Earth asteroids, and Mars flyby and/or landing. The question is therefore: Are we ready to go? To answer this with a yes, we are currently using the International Space Station to develop an integrated human physiological countermeasure suite. The integrated countermeasure suite will most likely encounter: 1) Exercise devices for aerobic, dynamic and resistive exercise training; 2) sensory‐motor computer training programs and anti‐motion sickness medication for preparing EVAs and G‐transitions; 3) lower limb bracelets for preventing and/or treating the VIIP (vision impairment and intracranial pressure) syndrome; 4) nutritional components for maintenance of bone, muscle, the cardiovascular system and preventing oxidative stress and damage and immune deficiencies (e. g. omega‐3 fatty acids, PRO/K, anti‐oxidants and less salt and iron); 5) bisphosphonates for preventing bone degradation.; 6) lower body compression garment and oral salt and fluid loading for landing on a planetary surface to combat orthostatic intolerance; 7) laboratory analysis equipment for individualized monitoring of biomarkers in blood, urine and saliva for estimation of health status in; 8) advanced ultrasound techniques for monitoring bone and cardiovascular health; and 9) computer modeling programs for individual health status assessments of efficiency and subsequent adjustments of countermeasures. In particular for future missions into deep space, we are concerned with the synergistic effects of weightlessness, radiation, operational constraints and other spaceflight environmental factors. Therefore, increased collaboration between physiological, behavioral, radiation and space vehicle design disciplines are strongly warranted. Another venue we are exploring in NASA's Human Research Program is the usefulness of artificial gravity for mitigating the health risks of long duration weightlessness.

Norsk, Peter↗
NASA NTRS2004

Comparing NASA and ESA Cost Estimating Methods for Human Missions to Mars

To compare working methodologies between the cost engineering functions in NASA Marshall Space Flight Center (MSFC) and ESA European Space Research and Technology Centre (ESTEC), as well as to set-up cost engineering capabilities for future manned Mars projects and other studies which involve similar subsystem technologies in MSFC and ESTEC, a demonstration cost estimate exercise was organized. This exercise was a direct way of enhancing not only cooperation between agencies but also both agencies commitment to credible cost analyses. Cost engineers in MSFC and ESTEC independently prepared life-cycle cost estimates for a reference human Mars project and subsequently compared the results and estimate methods in detail. As a non-sensitive, public domain reference case for human Mars projects, the Mars Direct concept was chosen. In this paper the results of the exercise are shown; the differences and similarities in estimate methodologies, philosophies, and databases between MSFC and ESTEC, as well as the estimate results for the Mars Direct concept. The most significant differences are explained and possible estimate improvements identified. In addition, the Mars Direct plan and the extensive cost breakdown structure jointly set-up by MSFC and ESTEC for this concept are presented. It was found that NASA applied estimate models mainly based on historic Apollo and Space Shuttle cost data, taking into account the changes in technology since then. ESA used models mostly based on European satellite and launcher cost data, taking into account the higher equipment and testing standards for human space flight. Most of NASA's and ESA s estimates for the Mars Direct case are comparable, but there are some important, consistent differences in the estimates for: 1) Large Structures and Thermal Control subsystems; 2) System Level Management, Engineering, Product Assurance and Assembly, Integration and Test/Verification activities; 3) Mission Control; 4) Space Agency Program Level activities.

Hunt, Charles D.↗
NASA NTRS2014

Nuclear Thermal Propulsion (NTP): A Proven, Growth Technology for Fast Transit Human Missions to Mars

The "fast conjunction" long surface stay mission option was selected for NASA's recent Mars Design Reference Architecture (DRA) 5.0 study because it provided adequate time at Mars (approx. 540 days) for the crew to explore the planet's geological diversity while also reducing the "1-way" transit times to and from Mars to approx. 6 months. Short transit times are desirable in order to reduce the debilitating physiological effects on the human body that can result from prolonged exposure to the zero-gravity (0-gE) and radiation environments of space. Recent measurements from the RAD detector attached to the Curiosity rover indicate that astronauts would receive a radiation dose of approx. 0.66 Sv (approx. 66 rem)-the limiting value established by NASA-during their 1-year journey in deep space. Proven nuclear thermal rocket (NTR) technology, with its high thrust and high specific impulse (Isp approx. 900 s), can cut 1-way transit times by as much as 50 percent by increasing the propellant capacity of the Mars transfer vehicle (MTV). No large technology scale-ups in engine size are required for these short transit missions either since the smallest engine tested during the Rover program-the 25 klbf "Pewee" engine is sufficient when used in a clustered arrangement of three to four engines. The "Copernicus" crewed MTV developed for DRA 5.0 is a 0-gE design consisting of three basic components: (1) the NTP stage (NTPS); (2) the crewed payload element; and (3) an integrated "saddle truss" and LH2 propellant drop tank assembly that connects the two elements. With a propellant capacity of approx. 190 t, Copernicus can support 1-way transit times ranging from approx. 150 to 220 days over the 15-year synodic cycle. The paper examines the impact on vehicle design of decreasing transit times for the 2033 mission opportunity. With a fourth "upgraded" SLS/HLV launch, an "in-line" LH2 tank element can be added to Copernicus allowing 1-way transit times of 130 days. To achieve 100 to 120 day transit times, Copernicus' saddle truss/drop tank assembly is replaced by a "star truss" assembly with paired modular drop tanks to further increase the vehicle's propellant capacity. The HLV launch count increases (from approx. 5 to 7) and a fourth engine is needed to reduce total mission burn time and gravity losses. Using a "split mission" approach, the NTPS, in-line tank and the saddle truss/LH2 drop tank elements can be configured as a pre-deployed Earth Return Vehicle/propellant tanker supporting 90-day crewed mission transits. The split mission approach also eliminates the need for on-orbit assembly. Mission scenario descriptions, key features and operational characteristics for five different vehicle configurations are presented.

Borowski, Stanley K.↗
NASA NTRS1997

Artificial gravity for human missions

The author examines the merits and problems associated with full-time rotation and intermittent G stimulation as weightlessness countermeasures during prolonged space flight.

NASA Discipline Neuroscience↗
NASA NTRS2015

The Solar Probe Plus Mission: Humanity's First Visit to Our Star

Solar Probe Plus (SPP) will be the first spacecraft to fly into the low solar corona. SPPs main science goal is to determine the structure and dynamics of the Suns coronal magnetic field, understand how the solar corona and wind are heated and accelerated, and determine what processes accelerate energetic particles. Understanding these fundamental phenomena has been a top-priority science goal for over five decades, dating back to the 1958 Simpson Committee Report. The scale and concept of such a mission has been revised at intervals since that time, yet the core has always been a close encounter with the Sun. The mission design and the technology and engineering developments enable SPP to meet its science objectives to: (1) Trace the flow of energy that heats and accelerates the solar corona and solar wind; (2) Determine the structure and dynamics of the plasma and magnetic fields at the sources of the solar wind; and (3) Explore mechanisms that accelerate and transport energetic particles. The SPP mission was confirmed in March 2014 and is under development as a part of NASAs Living with a Star (LWS) Program. SPP is scheduled for launch in mid-2018, and will perform 24 orbits over a 7-year nominal mission duration. Seven Venus gravity assists gradually reduce SPPs perihelion from 35 solar radii (RS) for the first orbit to less than 10 RS for the final three orbits. In this paper we present the science, mission concept and the baseline vehicle for SPP, and examine how the mission will address the key science questions.

Fox, N. J.↗
NASA NTRS1991

Radiation protection for human missions to the Moon and Mars

Radiation protection assessments are performed for advanced Lunar and Mars manned missions. The Langley cosmic ray transport code and the nucleon transport code are used to quantify the transport and attenuation of galactic cosmic rays and solar proton flares through various shielding media. Galactic cosmic radiation at solar maximum and minimum, as well as various flare scenarios are considered. Propagation data for water, aluminum, liquid hydrogen, lithium hydride, lead, and lunar and Martian regolith (soil) are included. Shield thickness and shield mass estimates required to maintain incurred doses below 30 day and annual limits (as set for Space Station Freedom and used as a guide for space exploration) are determined for simple geometry transfer vehicles. On the surface of Mars, dose estimates are presented for crews with their only protection being the carbon dioxide atmosphere and for crews protected by shielding provided by Martian regolith for a candidate habitat.

Simonsen, Lisa C.↗
NASA NTRS1993

Effect of Earth and Mars departure delays on human missions to Mars

This study determines the impact on the initial mass in low-Earth orbit (IMLEO) for delaying departure from Mars and Earth by 5, 15, and 30 days, once a nominal mission to Mars has been selected. Additionally, the use of a deep space maneuver (DSM) is attempted to alleviate the IMLEO penalties. Three different classes of missions are analyzed using chemical and nuclear thermal propulsion systems in the 2000-2025 time-frame: opposition, conjunction, and fast-transfer conjunction. The results indicate that Mars and Earth delays can lead to large IMLEO penalties. Opposition and fast-transfer conjunction class missions have the highest IMLEO penalties, upwards of 432.4 mt and 1977.3 mt, respectively. Conjunction class missions, on the other hand, tend to be insensitive to Mars and Earth delays having IMLEO penalties under 103.5 mt. As expected, nuclear thermal propulsion had significantly lower IMLEO penalties as compared to chemical propulsion. The use of a DSM is found not to have a significant impact on reducing the IMLEO penalties. Through this investigation, the effect of off-nominal departure conditions on the overall mission (i.e., IMLEO) can be gained, enabling mission designers to incorporate the influence of off-nominal departure conditions of the interplanetary trajectory in the overall conceptual design process of a Mars transfer vehicle.

Desai, Prasun N.↗
NASA NTRS1996

Exploring Mars for Evidence of Past or Present Life: Roles of Robotic and Human Missions

During the coming decade, robotic field science will play a fundamental role in exploring Mars for evidence of past life and/or prebiotic chemistry. To create a context for such exploration, we especially need to understand the mineralogy and chemistry of the Martian surface. We have learned that the preservation of biological signatures in rocks on Earth is favored by rapid mineralization processes that are restricted to a comparatively small number of geological settings. Thus, a detailed knowledge of surface mineralogy will provide valuable clues about past Martian environments as a necessary context for future exobiological exploration.

Farmer, Jack D.↗
NASA NTRS2006

Application of Solar-Electric Propulsion to Robotic and Human Missions in Near-Earth Space

Solar-electric propulsion (SEP) is becoming of interest for application to a wide range of missions. The benefits of SEP are strongly influenced by system element performance, especially that for the power system. Solar array performance is increasing rapidly and promises to continue to do so for another 10 to 20 years (Fig. 1). At the same time, cost per watt is decreasing. Radiation hardness is increasing. New concepts for how to design a SEP are emerging. These improvements lead to changes in the best ways to apply SEP technology to missions, and broadening of the practical uses of SEP technology compared to competing technologies. This paper addresses the evolving characteristics of SEP technology from the point of view of mission design, and how mission profile characteristics can be designed to best take advantage of evolving SEP characteristics. Mission concepts include robotic lunar landers and orbiters; scientific planetary spacecraft; delivery of spacecraft to geosynchronous orbit from inclined and low-inclination launch orbits; and lunar cargo delivery from Earth orbit to lunar orbit. Expendable and re-usable SEP profiles are considered. Flight control considerations are abstracted from recent papers by the author to describe how these influence SEP design and operations.

Woodcock, Gordon↗
NASA NTRS2009

Austere Human Missions to Mars

This slide presentation reviews a possible mission architecture for a more austere Mars mission, than the one developed by NASA outlined in the Design Reference Architecture 5 (DRA 5). "Austere" architecture is scaled back from DRA 5 and might offer lower development cost, lower flight cost, and lower development risk. This approach will not meet all the DRA 5 mission requirements. Included in the presentation are the elements of an Austere mission, diagrams of the trans-Mars injection (TMI), cruise, and Mars Orbital Insertion for various phases of the mission, the entry descent landing (EDL) concept. The key features of the Transit Habitat (TransHab), the Earth Departure Stage (EDS), the landers, are reviewed. A chart shows the Mass in tons, of the conceptual types of Mars Landers. The EDL concept, EDL Phase diagrams for the Mars Lander are reviewed. New technologies that would be required are also reviewed. Flight test programs for the various parts of the architecture and a flight schedule are reviewed.

transit habitat (TransHab)↗
NASA NTRS2002

Advanced Spacecraft Designs in Support of Human Missions to Earth's Neighborhood

NASA's strategic planning for technology investment draws on engineering studies of potential future missions. A number of hypothetical mission architectures have been studied. A recent study completed by The NASA/JSC Advanced Design Team addresses one such possible architecture strategy for missions to the moon. This conceptual study presents an overview of each of the spacecraft elements that would enable such missions. These elements include an orbiting lunar outpost at lunar L1 called the Gateway, a lunar transfer vehicle (LTV) which ferries a crew of four from the ISS to the Gateway, a lunar lander which ferries the crew from the Gateway to the lunar surface, and a one-way lunar habitat lander capable of supporting the crew for 30 days. Other supporting elements of this architecture discussed below include the LTV kickstage, a solar-electric propulsion (SEP) stage, and a logistics lander capable of re-supplying the 30-day habitat lander and bringing other payloads totaling 10.3 mt in support of surface mission activities. Launch vehicle infrastructure to low-earth orbit includes the Space Shuttle, which brings up the LTV and crew, and the Delta-IV Heavy expendable launch vehicle which launches the landers, kickstage, and SEP.

Fletcher, David↗