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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 1,117 records · Page 62
All sourcesNASA NTRSDOE OSTI
NASA NTRS2018

Comparison of Propulsion Options for Human Exploration of Mars

NASA continues to advance plans to extend human presence beyond low-Earth orbit leading to human exploration of Mars. The plans being laid out follow an incremental path, beginning with initial flight tests followed by deployment of a Deep Space Gateway (DSG) in cislunar space. This Gateway, will serve as the initial transportation node for departing and returning Mars spacecraft. Human exploration of Mars represents the next leap for humankind because it will require leaving Earth on a long mission with very limited return, rescue, or resupply capabilities. Although Mars missions are long, approaches and technologies are desired which can reduce the time that the crew is away from Earth. This paper builds off past analyses of NASA's exploration strategy by providing more detail on the performance of alternative in-space transportation options with an emphasis on reducing total mission duration. Key options discussed include advanced chemical, nuclear thermal, nuclear electric, solar electric, as well as an emerging hybrid propulsion system which utilizes a combination of both solar electric and chemical propulsion.

Drake, Bret G.↗
NASA NTRS2017

Four Bed Molecular Sieve - Exploration (4BMS-X) Virtual Heater Design and Optimization

A 4BMS-X (Four Bed Molecular Sieve - Exploration) design and heater optimization study for CO2 sorbent beds in proposed exploration system architectures is presented. The primary objectives of the study are to reduce heater power and thermal gradients within the CO2 sorbent beds while minimizing channeling effects. Some of the notable changes from the ISS (International Space Station) CDRA (Carbon Dioxide Removal Assembly) to the proposed exploration system architecture include cylindrical beds, alternate sorbents and an improved heater core. Results from both 2D and 3D sorbent bed thermal models with integrated heaters are presented. The 2D sorbent bed models are used to optimize heater power and fin geometry while the 3D models address end effects in the beds for more realistic thermal gradient and heater power predictions.

Schunk, R. Gregory↗
NASA NTRS2018

Challenges in Clinical Management of Radiation-Induced Illnesses in Exploration Spaceflight

Historical solar particle events (SPEs) provide context for some understanding of acute radiation exposure risk to astronauts traveling outside of low Earth orbit. Modeling of potential doses delivered to exploration crewmembers anticipates limited radiation-induced health impacts, including prodromal symptoms of nausea, emesis, and fatigue, but suggests that more severe clinical manifestations are unlikely. Recent large animal-model research in space-analogs closely mimicking SPEs has identified coagulopathic events independent of the hematopoietic sequelae of higher radiation doses, similar in manifestation to disseminated intravascular coagulation (DIC). We explored the challenges of clinical management of radiation-related clinical manifestations, using currently accepted modeling techniques and anticipated physiological sequelae, to identify medical capabilities needed to successfully manage SPE-induced radiation illnesses during exploration spaceflight.

Blue, Rebecca↗
NASA NTRS2018

Defining Medical Capabilities for Exploration Missions

Exploration-class missions to the moon, Mars and beyond will require a significant change in medical capability from today's low earth orbit centric paradigm. Significant increases in autonomy will be required due to differences in duration, distance and orbital mechanics. Aerospace medicine and systems engineering teams are working together within ExMC to meet these challenges. Identifying exploration medical system needs requires accounting for planned and unplanned medical care as defined in the concept of operations. In 2017, the ExMC Clinicians group identified medical capabilities to feed into the Systems Engineering process, including: determining what and how to address planned and preventive medical care; defining an Accepted Medical Condition List (AMCL) of conditions that may occur and a subset of those that can be treated effectively within the exploration environment; and listing the medical capabilities needed to treat those conditions in the AMCL. This presentation will discuss the team's approach to addressing these issues, as well as how the outputs of the clinical process impact the systems engineering effort.

Hailey, M.↗
NASA NTRS2017

SSERVI: Merging Science and Human Exploration

The NASA Solar System Exploration Research Virtual Institute (SSERVI) is a virtual institute focused on research and the intersection of science and exploration, training the next generation of lunar scientists, and community development. As part of the SSERVI mission, we act as a hub for the opportunities that engage the larger scientific and exploration communities in order to form a new interdisciplinary, research-focused collaborations.

SSERVI↗
NASA NTRS2017

Resource Prospector, the Decadal Survey and the Scientific Context for the Exploration of the Moon

The Inner Planets Panel of the Planetary Exploration Decadal Survey defined several science questions related to the origins, emplacement, and sequestration of lunar polar volatiles: 1. What is the lateral and vertical distribution of the volatile deposits? 2. What is the chemical composition and variability of polar volatiles? 3. What is the isotopic composition of the volatiles? 4. What is the physical form of the volatiles? 5. What is the rate of the current volatile deposition? A mission concept study, the Lunar Polar Volatiles Explorer (LPVE), defined a approximately $1B New Frontiers mission to address these questions. The NAS/NRC report, 'Scientific Context for the Exploration of the Moon' identified he lunar poles as special environments with important implications. It put forth the following goals: Science Goal 4a-Determine the compositional state (elemental, isotopic, mineralogic) and compositional distribution (lateral and depth) of the volatile component in lunar polar regions. Science Goal 4b-Determine the source(s) for lunar polar volatiles. Science Goal 4c-Understand the transport, retention, alteration, and loss processes that operate on volatile materials at permanently shaded lunar regions. Science Goal 4d-Understand the physical properties of the extremely cold (and possibly volatile rich) polar regolith. Science Goal 4e-Determine what the cold polar regolith reveals about the ancient solar environment.

Moon↗
NASA NTRS2009

Subcooling Cryogenic Propellants for Long Duration Space Exploration

The use of cryogenic propellants such as hydrogen and oxygen is crucial for exploration of the solar system because of their superior specific impulse capability. Future missions may require vehicles with the flexibility to remain in orbit or travel in space for months, necessitating long-term storage of these cryogens. One powerful technique for easing the challenge of cryogenic fluid storage is to remove energy from tlie cryogenic propellant by isobaricly subcooling them below their normal boiling point prior to launch. The isobaric subcooling of the cryogenic propellant will be performed by using a cold pressurant to maintain the tank pressure while the cryogen's temperature is simultaneously reduced. After launch, even with the use of the best insulation systems, heat will leak into the cold cryogenic propellant tank. However, the large heat capacity available in highly subcooled cryogenic propellants allows them to absorb the energy that leaks into the tank until the cryogen reaches its operational thermodynamic condition. During this period of heating of the subcooled cryogen there will be no loss of the propellant due to venting for pressure control. This simple technique can extend the operational life of a spacecraft or an orbital cryogenic depot many months with minimal mass penalty. Subcooling technologies for cryogenic propellants would thus provide the Exploration Systems Mission Directorate with an enhanced level of mission flexibility. However, there are a few challenges associated with subcooling cryogenic propellants since compact subcooling ground support equipment has not been demonstrated. This paper explores the beneficial impact of subcooling cryogenic propellants on the launch pad for long-term cryogenic propellant storage in space and proposes a novel method for implementing subcooling of cryogenic propellants for spacecraft such as the Ares V Earth Departure Stage (EDS). Analysis indicates that with a careful strategy to handle the subcooled cryogen it would be possible to store cryogenic propellants in space for many months without venting. A concept for subcooling the cryogenic propellant relatively quickly and inexpensively on the launch pad - the thermodynamic cryogen subcooler (TCS) - will be presented. Important components of the TCS and an associated subcooled cryogen tank (SCT) will be discussed in this paper. Results from a preliminary thermodynamic model of the performance of a TCS for an EDS sized hydrogen tank will also be presented.

Mustafi, Shuvo↗
NASA NTRS2014

Science Goals and Mission Concept for the Future Exploration of Titan and Enceladus

Saturn׳s moons, Titan and Enceladus, are two of the Solar System׳s most enigmatic bodies and are prime targets for future space exploration. Titan provides an analogue for many processes relevant to the Earth, more generally to outer Solar System bodies, and a growing host of newly discovered icy exoplanets. Processes represented include atmospheric dynamics, complex organic chemistry, meteorological cycles (with methane as a working fluid), astrobiology, surface liquids and lakes, geology, fluvial and aeolian erosion, and interactions with an external plasma environment. In addition, exploring Enceladus over multiple targeted flybys will give us a unique opportunity to further study the most active icy moon in our Solar System as revealed by Cassini and to analyse in situ its active plume with highly capable instrumentation addressing its complex chemistry and dynamics. Enceladus׳ plume likely represents the most accessible samples from an extra-terrestrial liquid water environment in the Solar system, which has far reaching implications for many areas of planetary and biological science. Titan with its massive atmosphere and Enceladus with its active plume are prime planetary objects in the Outer Solar System to perform in situ investigations. In the present paper, we describe the science goals and key measurements to be performed by a future exploration mission involving a Saturn-Titan orbiter and a Titan balloon, which was proposed to ESA in response to the call for definition of the science themes of the next Large-class mission in 2013. The mission scenario is built around three complementary science goals: (A) Titan as an Earth-like system; (B) Enceladus as an active cryovolcanic moon; and (C) Chemistry of Titan and Enceladus - clues for the origin of life. The proposed measurements would provide a step change in our understanding of planetary processes and evolution, with many orders of magnitude improvement in temporal, spatial, and chemical resolution over that which is possible with Cassini-Huygens. This mission concept builds upon the successes of Cassini-Huygens and takes advantage of previous mission heritage in both remote sensing and in situ measurement technologies.

future missions↗
NASA NTRS2018

Development of High Power Hall Thruster Systems to Enable the NASA Exploration Vision

The next phase of space exploration missions requires high power Solar Electric Propulsion (SEP) systems for large-scale science missions and cargo transportation. Development is underway at Aerojet Rocketdyne on Hall thruster systems that are intended to bracket the needs of future NASA SEP missions in support of space exploration. The Advanced Electric Propulsion System (AEPS) program is developing and qualifying a 13.3kW Hall thruster system to be demonstrated on the Power and Propulsion Element (PPE), which is intended to be the first element of a Lunar Outpost Platform - Gateway (LOP-G). The NextSTEP program is integrating a nested Hall thruster into a 100kW system and testing it for 100 hours. These two programs will provide a path to efficient in-space propulsion that will allow NASA to transfer the large amounts of cargo that is needed to support human missions - first to the moon and then on to Mars. The Advanced Electric Propulsion System (AEPS) program is completing development, qualification and delivery of five flight 13.3kW EP systems to NASA. The flight AEPS system includes a magnetically shielded long-life Hall thruster, Power Processing Unit (PPU) and a Xenon Flow Controller (XFC). The Hall thruster, developed and demonstrated by NASA, operates at input powers up to 12.5kW while providing a specific impulse over an estimated 2800s at an input voltage of 600V. The power processor is designed to accommodate an input voltage range of 95-140V, consistent with operation beyond the orbit of Mars. The integrated system input power is continuously throttleable between 3 and 13.3kW. Component level testing of the EP String has begun with prototype hardware. The NextSTEP program is developing a 100kW Electric Propulsion (EP) system using a nested Hall thruster designed for powers up to 250kW, a modular power processor and a modular mass flow controller. While the program objective is to operate the integrated EP system continuously at 100kW for 100hrs to demonstrate thermal stability and support the development of system life time models, it builds on decades of experience with long-life Hall thrusters and the design is evolvable to a capability of 250kW. Design upgrades that demonstrate the 100kW EP system have been completed and tested. Aerojet Rocketdyne (AR) is excited to support NASA as it extends human reach into deep space and believes that these programs will provide the propulsion to make such missions affordable and sustainable. These systems provide NASA with a range of options to power its deep space transport vehicles. This paper presents the mission requirements for supporting the NASA exploration vision, as well as the status for the high power Hall thruster systems in development.

Jackson, Jerry↗
NASA NTRS2018

Pulmonary Inflammatory Responses to Acute Meteorite Dust Exposures - Implications for Human Space Exploration

New initiatives to begin Lunar and Martian human surface operations within the next few decades are illustrative of the resurgence of interest in human space exploration. However, as with all exploration, there are risks. The previous manned missions to the Moon highlight a major hazard for future human exploration of the Moon and beyond: surface dust. Not only did the dust cause mechanical and structural integrity issues with the suits, the dust 'storm' generated upon reentrance into the crew cabin caused "lunar hay fever" and "almost blindness.". It was further reported that the allergic response to the dust worsened with each exposure. Due to the prevalence of these high exposures, the Human Research Roadmap developed by NASA identifies the Risk of Adverse Health and Performance Effects of Celestial Dust Exposure as an area of concern.

Harrington, A. D.↗
NASA NTRS2018

Development of High Power Hall Thruster Systems to Enable the NASA Exploration Vision

The next phase of space exploration missions requires high power Solar Electric Propulsion (SEP) systems for large-scale science missions and cargo transportation. Development is underway at Aerojet Rocketdyne on Hall thruster systems that are intended to bracket the needs of future NASA SEP missions in support of space exploration. The Advanced Electric Propulsion System (AEPS) program is developing and qualifying a 13.3kW Hall thruster system to be demonstrated on the Power and Propulsion Element (PPE), which is intended to be the first element of a Lunar Outpost Platform - Gateway (LOP-G). The NextSTEP program is integrating a nested Hall thruster into a 100 kW system and testing it for 100 hours. These two programs will provide a path to efficient in-space propulsion that will allow NASA to transfer the large amounts of cargo that is needed to support human missions - first to the moon and then on to Mars. The Advanced Electric Propulsion System (AEPS) program is completing development, qualification and delivery of five flight 13.3kW EP systems to NASA. The flight AEPS system includes a magnetically shielded long-life Hall thruster, Power Processing Unit (PPU) and a Xenon Flow Controller (XFC). The Hall thruster, developed and demonstrated by NASA, operates at input powers up to 12.5 kW while providing a specific impulse over an estimated 2800s at an input voltage of 600V. The power processor is designed to accommodate an input voltage range of 95-140V, consistent with operation beyond the orbit of Mars. The integrated system input power is continuously throttleable between 3 and 13.3kW. Component level testing of the EP String has begun with prototype hardware. The NextSTEP program is developing a 100kW Electric Propulsion (EP) system using a nested Hall thruster designed for powers up to 250kW, a modular power processor and a modular mass flow controller. While the program objective is to operate the integrated EP system continuously at 100kW for 100 hours to demonstrate thermal stability and support the development of system life time models, it builds on decades of experience with long-life Hall thrusters and the design is evolvable to a capability of 250kW. Design upgrades that demonstrate the 100kW EP system have been completed and tested. Aerojet Rocketdyne is excited to support NASA as it extends human reach into deep space and believes that these programs will provide the propulsion to make such missions affordable and sustainable. These systems provide NASA with a range of options to power its deep space transport vehicles. This paper presents the mission requirements for supporting the NASA exploration vision, as well as the status for the high power Hall thruster systems in development.

Jackson, Jerry↗
NASA NTRS2018

NASA's Space Launch System: Progress Toward Unmatched Exploration Capability

The Space Launch System (SLS) Program delivered the first element of the exploration-class rocket and completed manufacturing of all major structural elements in 2017. The Program continues component integration and testing in 2018 in preparation for the inaugural launch of NASA's new deep space exploration system in fiscal year 2020. SLS represents a new strategic national capability designed for the most challenging human and robotic exploration and is engineered for overall mission success. This paper will discuss the technical and programmatic successes and challenges of the past year and look ahead to plans for 2018 and 2019.

Honeycutt, John↗
NASA NTRS2018

Composite Technology for Exploration (CTE)

Technology Product Capability: The CTE (Composite Technology for Exploration) project will develop and demonstrate critical composites technologies with a focus on weight-saving, performance-enhancing bonded joint technology for Space Launch System (SLS)-scale composite hardware to support future NASA exploration missions - Improve the analytical capabilities required to predict failure modes in composite structures; - and, Support SLS payload adapters and fittings by maturing composite bonded joint technology and analytical tools to enable risk reduction. Exploration & Science Impact: Lighter weight structures; Improved material predictive capabilities; Improved bonded joint failure load and mode predictions to help reduce knockdown factors; and improve predictability and reliability; Increase confidence of all bonded joint composite structures; Reduce reliance on expensive testing.

CTE↗
NASA NTRS2018

NASA SSERVI: Merging Science and Human Exploration

The NASA Solar System Exploration Research Virtual Institute (SSERVI) is a virtual institute focused on research at the intersection of science and exploration, training the next generation of lunar scientists, and community development. As part of the SSERVI mission, we act as a hub for opportunities that engage the larger scientific and exploration communities in order to form new interdisciplinary, research-focused collaborations. This talk will describe the research efforts of the thirteen domestic teams that constitute the U.S. complement of the Institute and how we will engage the community through workshops, conferences, online seminars and classes, student exchange programs and internships.

SSERVI↗
NASA NTRS2018

Needs and Opportunities in the Development of Advanced Materials and Manufacturing Methods for Future Long-Duration Human Space Exploration

Weight, functionality, and sustainability are all critical concerns for future, long-duration, human exploration of space. Exploration missions will be mass-limited, since the amount of supplies and instruments that future astronauts will be able to take with them will be limited by launch vehicle and spacecraft mass and efficiency. Astronauts will need to have the capability to repair or replace worn-out or broke hardware and produce new components to be able to function for long periods at locations far-removed from Earth. Ultra-lightweight, multifunctional materials will be required to enable significant reductions in launch vehicle, spacecraft, and habitat mass in order to maximize payload. "Mass-less Exploration" concepts must be developed that will recycle materials and waste and convert available planetary materials into new feedstock materials and utilize in-space additive manufacturing to use these materials to produce the

composites↗
NASA NTRS2018

NASA's Space Launch System: Testing for Deep Space Human Exploration

NASA’S Exploration Plans: National Space Policy Directive 1: NASA to “… Beginning with missions beyond low-Earth orbit, the United States will lead the return of humans to the Moon for long-term exploration and utilization, followed by human missions to Mars and other destinations.” - Today: Work in Low Earth Orbit with ISS: Commercial Partners supporting logistics and soon taking humans to ISS (International Space Station) - Next Step: Gateway human-tended station, robotic landers and rovers, eventually people, at the Moon - Ultimately: Continued robotic exploration of Mars to inform future crewed missions.

Blevins, John↗
NASA NTRS2018

Field Camp for Astronauts: NASA's Geoscience Training Program for Planetary Exploration

Fifty years ago Apollo astronauts walked on the Moon to explore the geology and collect samples for Earth return. Several authors have discussed the strategic planning and training that enabled the Apollo successes, and assembled recommendations regarding today’s lunar science objectives and astronaut training required to achieve those science goals. Since the 1980s, geoscience training for astronauts focused on observing the Earth from orbit. Today, we are building a geoscience training program to support informed Earth observations as well as the exploration culture for future human missions to the Moon and Mars. Our team partnered with JSC’s crew training and astronaut offices to develop our 4-week geoscience program for the 2017 astronaut class. Because the astronauts have a variety of professional backgrounds, we provide a broad introduction to Earth and planetary sciences. But our prime focus is 2 weeks of intensive field work, a methodology introduced with the 2013 astronaut class. We completed the first half of the training – a field trip to observe hurricane deposits along Galveston Bay; keynotes by Apollo colleagues highlighting Apollo experiences; a tightly-integrated week of introductory geology in the classroom followed by a week of fieldwork in the Rio Grande del Norte National Monument. The classroom included interactive map exercises that allowed the students to progressively build a base map of the field area that they used as a starting point for their week-long mapping exercise. We divided the class into small mapping groups to conduct their observations, mapping and interpretation of the geology. In addition to learning geological field work, our field training provided the platform for practicing expeditionary leadership, a key skill set valued by NASA for astronaut crews. Next summer the capstone fieldwork for the 2017 astronauts will include both mapping and rock sampling. Throughout the mapping, the class will collect additional data to help inform field and sampling decisions using diagnostic field instruments that are being tested in analog settings for their operational efficacy for future planetary exploration.

Evans, Cynthia A.↗
NASA NTRS2019

NASA’s Space Launch System: Enabling a New Generation of Lunar Exploration

SLS (Space Launch System) is designed to meet the nation’s goals for human exploration, and to be a game-changing launch vehicle for breakthrough science missions. Built to Explore: As you can see, we have a lot of hardware in progress. In fact, most of the EM-1 (Exploration Mission-1) vehicle is manufactured and a lot of it is complete and delivered to KSC (Kennedy Space Center), where it will be stacked and launched. But we’re not just working the first Block 1 vehicle for EM-1. In fact, I work payload integration and we’re actively working on four flights at the moment! So, let me tell you about what we’re doing to create a system for returning astronauts to the Moon and building the Gateway.

Smith, David Alan↗