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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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NASA NTRS1986

Infrared spectral studies of asteroids

The first comprehensive spectrophotometric survey in the near-infrared (0.8 to 2.5 microns) was carried out with the NASA Infrared Telescope Facility and special filters optimized for spectroscopy of solid surfaces. About 105 asteroids have been observed (in 52 photometric passbands) to date. These spectra provide a much improved database for determining the mineralogy of the various asteroid spectral classes previously defined on the basis of visible (0.3 to 1.0 micron) data. Preliminary results from analysis of these spectra include: (1)Class "A" asteroids are dominated by olivine and correspond to the rare brachinite meteorites; (2)Class "S" asteroids have highly variable olivine/pyroxene ratios inconsistent with chondritic compositions; (3)Classes "P" and "D" are apparently "ultracarbonacous" material which extends the known range of chondrites to lower condensation temperatures; (4)The distribution of spectral types shows that the asteroids were heated by a mechanism whose intensity declined rapidly with solar distance; and (5)Spectra of the proposed flyby targets for CRAF were used to evaluate the results obtainable from this mission.

Bell, J. F.↗

NASA NTRSDate not supplied

LIPA: Lunar Ice Perception Algorithm

Introduction: The highest concentration of Lu-nar water-ice stores exists within the Permanently Shadowed Regions (PSRs) of the Lunar South Pole [1-3]. As such, the ability to locate in situ water-ice stores in an accurate, systematic, and safe manner will prove vital for future Lunar activities which rely on hydrogen-based resources. Here we show how the strong absorptive properties of ice can be exploited so that surface ice located in PSRs can be easily differentiated from the surrounding frozen regolith. Testbeds which simulate an icy lunar landscape were created and then systematically imaged using a mid-wave infrared (MWIR) camera system. Testbeds were imaged under two filter modes (1) high-absorption (high-abs) mode: whereby imagery captured were confined to a single central wave-length (CWL) of 3.15 ± 0.03 μm and (2) low-absorption (low-abs) mode: whereby imagery cap-tured were confined to a single CWL of 3.80 ± 0.04 μm (Figure 1). High- and low-absorption modes are related to the absorptive properties of ice at each selected wavelength, respectively. Corresponding images from each filter mode were differenced (i.e., pixels were subtracted) to enhance contrast between ice-bearing and non-ice-bearing pixels, and then fed into a semantic segmen-tation model. The model was trained to detect and differentiate between water, ice, shadows, and lunar regolith. Results: Modeling results accurately discrimi-nated ice from other materials (such as frozen lunar regolith) and were used to visually resolve the spa-tial extent of surface ice. Further, outputs produced through semantic segmentation were used to estimate water-ice contents in collected imagery [(Pixels with Class = “Water Ice”)/(Sum of Pixels)*100]. Summary: These works prove promising for future in situ resource utilization (ISRU) missions which employ robotics in combination with infrared camera systems to advance science objectives (e.g., locate water-ice in frozen regolith) on the lunar sur-face. References: [1] Cannon K. M., Deutsch A. N., Head J. W., and Britt D. T. (2020) Geophysical Re-search Letters, 46, e2020GL088920. [2] Honniball C. I. et al. (2021) Nature Astronomy 5, no. 2, 121-127. [3] Li S. et al. (2018) Proceedings of the National Academy of Sciences, 115(36), 8907-8912.

A. Slabic↗

NASA NTRS1993

Precision optical interferometry in space

POINTS, an astrometric Optical interferometer with a nominal measurement accuracy of 5 microarcseconds for the angle between a pair of stars separated by about 90 deg, is presently under consideration by two divisions of NASA-OSSA. It will be a powerful new multi-disciplinary tool for astronomical research. If chosen as the TOPS-1 (Toward Other Planetary Systems) instrument by the Solar-System Exploration Division, it will perform a definitive search for extra-solar planetary systems, either finding and characterizing a large number of them or showing that they are far less numerous than now believed. If chosen as the AIM (Astrometric Interferometry Mission) by the Astrophysics Division, POINTS will open new areas of astrophysical research and change the nature of the questions being asked in some old areas. In either case. it will be the first of a new class of powerful instruments in space and will prove the technology for the larger members of that class to follow. Based on a preliminary indication of the observational needs of the two missions, we find that a single POINTS mission will meet the science objectives of both TOPS-1 and AIM. The instrument detects dispersed fringe (channel led spectrum) and therefore can tolerate large pointing errors.

Reasenberg, Robert D.↗

NASA NTRS1972

Solar electric low-thrust Mercury orbiter missions.

Results of a preliminary study of unmanned Mercury orbiter missions which might be flown in the early 1980s. Five different levels of orbiter size and complexity are considered, ranging from a small orbiter carrying 22 kg of low data-rate instruments to a dual satellite mission employing 110 kg of science instruments emphasizing regional and local scale surface imagery. An Intermediate-20 class launch vehicle is required to deliver a minimal surface-imaging science package into Mercury orbit using a ballistic mission mode. Employment of a 15 kW solar electric low-thrust stage permits delivery of the more capable dual satellite package with a Titan IIID (5)/Centaur.

Klopp, D. A.↗

NASA NTRS1984

Spaceborne sensors (1983-2000 AD): A forecast of technology

A technical review and forecast of space technology as it applies to spaceborne sensors for future NASA missions is presented. A format for categorization of sensor systems covering the entire electromagnetic spectrum, including particles and fields is developed. Major generic sensor systems are related to their subsystems, components, and to basic research and development. General supporting technologies such as cryogenics, optical design, and data processing electronics are addressed where appropriate. The dependence of many classes of instruments on common components, basic R&D and support technologies is also illustrated. A forecast of important system designs and instrument and component performance parameters is provided for the 1983-2000 AD time frame. Some insight into the scientific and applications capabilities and goals of the sensor systems is also given.

Kostiuk, T.↗

NASA NTRS2012

Multiple Smaller Missions as a Direct Pathway to Mars Sample Return

Recent discoveries by the Mars Exploration Rovers, Mars Express, Mars Odyssey, and Mars Reconnaissance Orbiter spacecraft include multiple, tantalizing astrobiological targets representing both past and present environments on Mars. The most desirable path to Mars Sample Return (MSR) would be to collect and return samples from that site which provides the clearest examples of the variety of rock types considered a high priority for sample return (pristine igneous, sedimentary, and hydrothermal). Here we propose an MSR architecture in which the next steps (potentially launched in 2018) would entail a series of smaller missions, including caching, to multiple landing sites to verify the presence of high priority sample return targets through in situ analyses. This alternative architecture to one flagship-class sample caching mission to a single site would preserve a direct path to MSR as stipulated by the Planetary Decadal Survey, while permitting investigation of diverse deposit types and providing comparison of the site of returned samples to other aqueous environments on early Mars

Niles, P. B.↗

NASA NTRS2021

A Dedicated Relay Network to Enable the Future of Mars Exploration

A highly successful international collaboration, the “Mars Relay Network” (MRN) leverages the combined NASA and ESA orbiter capabilities to transfer data to and from Mars surface missions. The MRN has admirably flight-demonstrated the benefits of a relay network and validated how international protocol standards may be used to ensure interoperability. However, principally designed for science missions, these orbiters addressed relay requirements as a secondary function, which introduced limitations to what can be achieved with the network. Next-decade missions are expected to have significantly greater communication needs than can be accommodated by the aging MRN. This paper reports the results of a broad study that evaluated the potential of a next-generation relay network, referencing the current MRN as a benchmark. A wide variety of orbital altitudes, surface latitudes, and mission scenarios were evaluated around a specific set of assumptions regarding the telecommunications payloads included. The study outlined how current day technologies could be applied to greatly enhance the data throughput to and from Mars on behalf of future science and reconnaissance missions. The instantiation of such a network would be enabling for a variety of missions and mission classes that have been heretofore unachievable, including both large and small orbiters, and landed vehicles representing new mission types (i.e. climbers, diggers, drones, etc.), and further argues that such a network would be instrumental in advancing human exploration interests at Mars.

Davis, Richard M.↗

NASA NTRS1994

(abstract) A Solar Electric Propulsion Mission to the Moon and Beyond!

The technological development of solar electric propulsion has advanced significantly over the last few years. Mission planners are now seriously studying which missions would benefit most from solar electric propulsion (SEP) and NASA's Solar System Exploration Division is contributing funding to ground and space qualification tests. In response to the impending release of NASA's Announcement of Opportunity for Discovery class planetary missions, we have undertaken a pre-Phase A study of a SEP mission to the Moon. This mission will not only return a wealth of new scientific data but will open up a whole new era of planetary exploration.

solar electric propulsion SEP Moon↗

NASA NTRS2016

Large Observatory for X-ray Timing (LOFT-P): A Probe-Class Mission Concept Study

LOFT-P is a mission concept for a NASA Astrophysics Probe-Class (less than $1B) X-ray timing mission, based on the LOFT M-class concept originally proposed to ESA's M3 and M4 calls. LOFT-P requires very large collecting area, high time resolution, good spectral resolution, broadband spectral coverage (2-30 keV), highly flexible scheduling, and an ability to detect and respond promptly to time-critical targets of opportunity. Many of LOFTP's targets are bright, rapidly varying sources, so these measurements are synergistic to imaging and high-resolution spectroscopy instruments, addressing much smaller distance scales than are possible without very long baseline X-ray interferometry, and using complementary techniques to address the geometry and dynamics of emission regions. LOFT-P was presented as an example mission to the head of NASA's Astrophysics Division, to demonstrate the strong community support for creation of a probe-class, for missions costing between $500M and $1B. We submitted a white paper4 in response to NASA PhysPAG's call for white papers: Probe-class Mission Concepts, describing LOFT-P science and a simple extrapolation from the ESA study costs. The next step for probe-class missions will be input into the NASA Astrophysics Decadal Survey to encourage the creation of a probe-class opportunity. We report on a 2016 study by MSFC's Advanced Concepts Office of LOFT-P, a US-led probe-class LOFT concept.

x-ray↗

NASA NTRS2008

The User Community and a Multi-Mission Data Project: Services, Experiences and Directions of the Space Physics Data Facility

From a user's perspective, the multi-mission data and orbit services of NASA's Space Physics Data Facility (SPDF) project offer a unique range of important data and services highly complementary to other services presently available or now evolving in the international heliophysics data environment. The VSP (Virtual Space Physics Observatory) service is an active portal to a wide range of distributed data sources. CDAWeb (Coordinate Data Analysis Web) enables plots, listings and file downloads for current data cross the boundaries of missions and instrument types (and now including data from THEMIS and STEREO). SSCWeb, Helioweb and our 3D Animated Orbit Viewer (TIPSOD) provide position data and query logic for most missions currently important to heliophysics science. OMNIWeb with its new extension to 1- and 5-minute resolution provides interplanetary parameters at the Earth's bow shock as a unique value-added data product. SPDF also maintains NASA's CDF (common Data Format) standard and a range of associated tools including translation services. These capabilities are all now available through webservices-based APIs as well as through our direct user interfaces. In this paper, we will demonstrate the latest data and capabilities now supported in these multi-mission services, review the lessons we continue to learn in what science users need and value in this class of services, and discuss out current thinking to the future role and appropriate focus of the SPDF effort in the evolving and increasingly distributed heliophysics data environment.

Fung, Shing F.↗

NASA NTRS2012

Mechanically-Deployed Hypersonic Decelerator and Conformal Ablator Technologies for Mars Missions

The concept of a mechanically deployable hypersonic decelerator, developed initially for high mass (~40 MT) human Mars missions, is currently funded by OCT for technology maturation. The ADEPT (Adaptive, Deployable Entry and Placement Technology) project has broad, game-changing applicability to in situ science missions to Venus, Mars, and the Outer Planets. Combined with maturation of conformal ablator technology (another current OCT investment), the two technologies provide unique low mass mission enabling capabilities otherwise not achievable by current rigid aeroshell or by inflatables. If this abstract is accepted, we will present results that illustrate the mission enabling capabilities of the mechanically deployable architecture for: (1) robotic Mars (Discovery or New Frontiers class) in the near term; (2) alternate approaches to landing MSL-class payloads, without the need for supersonic parachute or lifting entry, in the mid-term; and (3) Heavy mass and human missions to Mars in the long term.

Venkatapathy, Ethiraj↗

NASA NTRS2002

Technology Development and Advanced Planning for Curation of Returned Mars Samples

NASA Johnson Space Center (JSC) curates extraterrestrial samples, providing the international science community with lunar rock and soil returned by the Apollo astronauts, meteorites collected in Antarctica, cosmic dust collected in the stratosphere, and hardware exposed to the space environment. Curation comprises initial characterization of new samples, preparation and allocation of samples for research, and clean, secure long-term storage. The foundations of this effort are the specialized cleanrooms (class 10 to 10,000) for each of the four types of materials, the supporting facilities, and the people, many of whom have been doing detailed work in clean environments for decades. JSC is also preparing to curate the next generation of extraterrestrial samples. These include samples collected from the solar wind, a comet, and an asteroid. Early planning and R\&D are underway to support post-mission sample handling and curation of samples returned from Mars. One of the strong scientific reasons for returning samples from Mars is to search for evidence of current or past life in the samples. Because of the remote possibility that the samples may contain life forms that are hazardous to the terrestrial biosphere, the National Research Council has recommended that all samples returned from Mars be kept under strict biological containment until tests show that they can safely be released to other laboratories. It is possible that Mars samples may contain only scarce or subtle traces of life or prebiotic chemistry that could readily be overwhelmed by terrestrial contamination . Thus, the facilities used to contain, process, and analyze samples from Mars must have a combination of high-level biocontainment and organic / inorganic chemical cleanliness that is unprecedented. JSC has been conducting feasibility studies and developing designs for a sample receiving facility that would offer biocontainment at least the equivalent of current maximum containment BSL-4 (BioSafety Level 4) laboratories, while simultaneously maintaining cleanliness levels equaling those of state-of-the-art cleanrooms. Unique requirements for the processing of Mars samples have inspired a program to develop handling techniques that are much more precise and reliable than the approach (currently used for lunar samples) of employing gloved human hands in nitrogen-filled gloveboxes. Individual samples from Mars are expected to be much smaller than lunar samples, the total mass of samples returned by each mission being 0.5- 1 kg, compared with many tens of kg of lunar samples returned by each of the six Apollo missions. Smaller samples require much more of the processing to be done under microscopic observation. In addition, the requirements for cleanliness and high-level containment would be difficult to satisfy while using traditional gloveboxes. JSC has constructed a laboratory to test concepts and technologies important to future sample curation. The Advanced Curation Laboratory includes a new-generation glovebox equipped with a robotic arm to evaluate the usability of robotic and teleoperated systems to perform curatorial tasks. The laboratory also contains equipment for precision cleaning and the measurement of trace organic contamination.

Lindstrom, David J.↗

NASA NTRS1991

Radiological health risks for exploratory class missions in space

The radiation risks to crewmembers on missions to the moon and Mars are studied. A graph is presented of the cross section as a function of linear energy transfer (LET) for cell inactivation and neoplastic cell transformation. Alternatives to conventional approaches to radiation protection using dose and Q are presented with attention given to a hybrid of the conventional system for particles with LET less than 100 keV/micron.

Nachtwey, D. Stuart↗

NASA NTRS1986

A review of the multimegawatt MPD thruster and current mission applications

The magnetoplasmadynamic (MPD) thruster is potentially capable of providing 20-200 N of steady-state thrust, at 1000-20,000 s specific impulse while consuming a variety of propellants and megawatts of DC power. The specific impulse and power capacity put the MPD thruster in a class separate from other electric propulsion engines. Several types of missions are enhanced by the unique capabilities of a nuclear-electric driven MPD thruster and these include earth-orbit raising, cis-lunar transportation, and planetary exploration. This paper describes current MPD thruster technology, and several missions typical of the above cited categories.

King, D. Q.↗

NASA NTRS2004

Sample Return Science by Hayabusa Near-Earth Asteroid Mission

Assigning the material species to each asteroid spectral type and finding out the corresponding meteorite category is crucial to make the global material map in the whole asteroid belt and to understand the evolution of the asteroid belt. Recent direct observations by spacecrafts are revealing new intriguing aspects of asteroids which cannot be obtained solely from ground-based observations or meteorite studies. However identification of the real material species constituting asteroids and their corresponding meteorite analogs are still ambiguous. Space weathering makes difficult to identify the true material, and there is still a great gap between the remote sensing data on the global surface and the local microscopic data from meteorites. Sample return from asteroids are inevitable to solve these problems. For this purpose sample return missions to asteroids belonging to various spectral classes are required. The HAYABUSA spacecraft (prelaunch name is MUSESC) launched last year is the first attempt on this concept. This report presents outline of the mission with special stress on its science.

Fujiwara, A.↗

NASA NTRS1972

Space storable propellant acquisition system

Surface tension propellant acquisition concepts for an advanced spacecraft propulsion system having a 10-year mission capability were investigated. Surface tension systems were specified because they were shown to be the best propellant acquisition technique for various interplanetery spacecraft in a prior study. A variety of surface tension concepts for accomplishing propellant acquisition were formulated for the baseline space storable propulsion module and Jupiter Orbiter mission. Analyses and evaluations were then conducted on each candidate concept to assess fabricability, performance capability, and spacecraft compatibility. A comparative evaluation of the results showed the Fruhof-class of low-g surface tension systems to be preferred for these interplanetary applications.

Tegart, J. R.↗

NASA NTRSDate not supplied

Spaceflight Medical Evacuation Risk Assessment Principles - A Qualitative Investigation

BACKGROUND Future human space exploration beyond Low Earth Orbit (LEO) will require innovative solutions in many areas, primarily those that provide direct medical support to crew on long-duration missions and optimize their health and performance. The associated challenges therein will be numerous, including but not necessarily limited to extended one-way or "asynchronous" communication delays, minimal to non-existent resupply, and a prolonged transit time to "definitive care" ranging from 3-days to 9-months. At the same time, long-duration exploration spacecraft and crew will face restrictions on mass, power, volume, and data far more significant than that seen in current LEO settings. Given these limitations, medical risk assessment is of primary importance, especially evaluating the implications of a medical evacuation of an ill or injured crewmember. Such evacuations are complicated, potentially dangerous, and well may be impossible in certain phases of the mission. Regardless, such issues must be weighed against the risks of the injured crew remaining aboard a spacecraft with limited medical resources. OBJECTIVE This qualitative study drew from the experiences of subject matter experts (SMEs) in spaceflight and appropriate analog environments (i.e., military, disaster, and extreme environment fields) to identify unique principles common amongst medical evacuation considerations helpful in informing future risk assessment tools. Appropriate analog environments included austere operational settings where multiple factors (weather, logistics/limited resupply, denied/extreme environments, and patient condition) resulted in a limited ability to provide definitive local medical care. The fundamental principles in question revolved around scenarios where evacuation became a complicating yet necessary consideration and where life-threatening medical concerns had to be weighed against critical mission objective(s). The primary authors collected semi-structured data gathered through in-depth interviews with 16 subject matter experts (SMEs). Interview questions investigated how these SMEs consider and weigh the attendant risks present in medical evacuation scenarios. Among the critical questions posed were those that sought to understand how the SME balanced the challenges and requirements of medical evacuation (or keeping an injured patient "on-site" aka: "prolonged field care") against the evacuation operation's risks on impacting overarching mission success. The team analyzed interview transcripts for common themes and principles using the qualitative methods of thematic analysis based on consensus, co-occurrence, and comparison. As a result, nine primary risk consideration themes and nine contributing factor themes emerged, all of which will ideally inform future medical evacuation decision-making tools and operational decision-making for exploration class missions. Specific aims for this study included: 1. Identification of common principles used to assess risks and benefits of medical evacuations in extreme environments 2. Identification of common points of friction or complication and challenges in extreme environment evacuations

A T Almand↗

NASA NTRS2007

The NASA "PERS" Program: Solid Polymer Electrolyte Development for Advanced Lithium-Based Batteries

In fiscal year 2000, The National Aeronautics and Space Administration (NASA) and the Air Force Research Laboratory (AFRL) established a collaborative effort to support the development of polymer-based, lithium-based cell chemistries and battery technologies to address the next generation of aerospace applications and mission needs. The ultimate objective of this development program, which was referred to as the Polymer Energy Rechargeable System (PERS), was to establish a world-class technology capability and U.S. leadership in polymer-based battery technology for aerospace applications. Programmatically, the PERS initiative exploited both interagency collaborations to address common technology and engineering issues and the active participation of academia and private industry. The initial program phases focused on R&D activities to address the critical technical issues and challenges at the cell level. Out of a total of 38 proposals received in response to a NASA Research Announcement (NRA) solicitation, 18 proposals (13 contracts and 5 grants) were selected for initial award to address these technical challenges. Brief summaries of technical approaches, results and accomplishments of the PERS Program development efforts are presented. With Agency support provided through FY 2004, the PERS Program efforts were concluded in 2005, as internal reorganizations and funding cuts resulted in shifting programmatic priorities within NASA. Technically, the PERS Program participants explored, to various degrees over the lifetime of the formal program, a variety of conceptual approaches for developing and demonstrating performance of a viable advanced solid polymer electrolyte possessing the desired attributes, as well as several participants addressing all components of an integrated cell configuration. Programmatically, the NASA PERS Program was very successful, even though the very challenging technical goals for achieving a viable solid polymer electrolyte material or the overall envisioned long-term, program objectives were not met due to funding reductions. The NASA PERS Program provided research opportunities and generated and disseminated a wealth of new scientific knowledge and technical competencies within the polymer electrolyte area.

Baldwin, Richard S.↗