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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 NTRS2008

Evolution of the Earth Observing System (EOS) Data and Information System (EOSDIS)

One of the strategic goals of the U.S. National Aeronautics and Space Administration (NASA) is to "Develop a balanced overall program of science, exploration, and aeronautics consistent with the redirection of the human spaceflight program to focus on exploration". An important sub-goal of this goal is to "Study Earth from space to advance scientific understanding and meet societal needs." NASA meets this subgoal in partnership with other U.S. agencies and international organizations through its Earth science program. A major component of NASA s Earth science program is the Earth Observing System (EOS). The EOS program was started in 1990 with the primary purpose of modeling global climate change. This program consists of a set of space-borne instruments, science teams, and a data system. The instruments are designed to obtain highly accurate, frequent and global measurements of geophysical properties of land, oceans and atmosphere. The science teams are responsible for designing the instruments as well as scientific algorithms to derive information from the instrument measurements. The data system, called the EOS Data and Information System (EOSDIS), produces data products using those algorithms as well as archives and distributes such products. The first of the EOS instruments were launched in November 1997 on the Japanese satellite called the Tropical Rainfall Measuring Mission (TRMM) and the last, on the U.S. satellite Aura, were launched in July 2004. The instrument science teams have been active since the inception of the program in 1990 and have participation from Brazil, Canada, France, Japan, Netherlands, United Kingdom and U.S. The development of EOSDIS was initiated in 1990, and this data system has been serving the user community since 1994. The purpose of this chapter is to discuss the history and evolution of EOSDIS since its beginnings to the present and indicate how it continues to evolve into the future. this chapter is organized as follows. Sect. 7.2 provides a discussion of EOSDIS, its elements and their functions. Sect. 7.3 provides details regarding the move towards more distributed systems for supporting both the core and community needs to be served by NASA Earth science data systems. Sect. 7.4 discusses the use of standards and interfaces and their importance in EOSDIS. Sect. 7.5 provides details about the EOSDIS Evolution Study. Sect. 7.6 presents the implementation of the EOSDIS Evolution plan. Sect. 7.7 briefly outlines the progress that the implementation has made towards the 2015 Vision, followed by a summary in Sect. 7.8.

Ramapriyan, Hampapuram K.↗
DOE OSTI2025

A gravity-based mounting approach for large-scale cryogenic calorimeter arrays

Cryogenic calorimeters are among the leading technologies for searching for rare events. The CUPID experiment is exploiting this technology to deploy a tonne-scale detector to search for neutrinoless double-beta decay of 100 Mo. The CUPID collaboration proposed an innovative approach to assembling cryogenic calorimeters in a stacked configuration, held in position solely by gravity. This gravity-based assembly method is unprecedented in the field of cryogenic calorimeters and offers several advantages, including relaxed mechanical tolerances and simplified construction. To assess and optimize its performance, we constructed a medium-scale prototype hosting 28 Li 2 MoO 4 crystals and 30 Ge light detectors, both operated as cryogenic calorimeters at the Laboratori Nazionali del Gran Sasso (Italy). Despite an unexpected excess of noise in the light detectors, the results of this test proved (i) a thermal stability better than ±0.5 mK at 10 mK, (ii) a good energy resolution of Li 2 MoO 4 cryogenic calorimeters, (6.6 ± 2.2) keV FWHM at 2615 keV, and (iii) a Li 2 MoO 4 light yield measured by the closest light detector of 0.36 keV/MeV, sufficient to guarantee the particle identification requested by CUPID.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
NASA NTRS2003

Validation of the Measurement of Pollution in the Troposphere (MOPITT) Experiment by Ground-Based Infrared Solar Spectroscopic Measurements of Carbon Monoxide (CO) and Methane (CH4)

The goal of the MOPITT experiment is to enhance our knowledge of the lower atmosphere system and particularly how it interacts with the surface/ocean/biomass systems. The particular focus is the distribution, transport, sources and sinks of carbon monoxide and methane in the troposphere. The MOPITT instrument was launched on EOS TERRA satellite December 18, 1999. After the launch and until March 22, 2000 the MOPITT instrument was in engineering and calibration mode. Beginning March 23, 2000 through May 6, 2001 the instrument was in a science measurement mode with some calibration breaks. On May 7, 2001 a criocooler on a side B died and channels 1 - 4 became inoperational. The MOPITT resumed its scientific measurements on August 25, 2001 with channels 5 - 8. With some calibration breaks the instrument currently provides the data. The project has three elements to it: hardware, data analysis and modeling. The MOPITT instrument, on the NASA EOS Terra satellite, measures the upwelling infrared radiance. Using the technique of correlation spectroscopy, information regarding the distribution of atmospheric CO and CH4 can be extracted. By using appropriate data analysis techniques, concentration profiles of CO are currently obtained on a global basis at a reasonably high horizontal (approximately 22km) and vertical resolution (approximately 3km). Column amounts of methane will be derived over the sunlit side of the orbit. These profiles are assimilated into models to study the chemistry and dynamics of CO, CH4 and other constituents of the lower atmosphere.

Pougatchev, Nikita↗
NASA NTRS2015

Planetary Science with Balloon-Borne Telescopes

The National Aeronautics and Space Administration (NASA) and the planetary science community have recently been exploring the potential contributions of stratospheric balloons to the planetary science field. A study that was recently concluded explored the roughly 200 or so science questions raised in the Planetary Decadal Survey report and found that about 45 of those questions are suited to stratospheric balloon based observations. In September of 2014, a stratospheric balloon mission called BOPPS (which stands for Balloon Observation Platform for Planetary Science) was flown out of Fort Sumner, New Mexico. The mission had two main objectives, first, to observe a number of planetary targets including one or more Oort cloud comets and second, to demonstrate the applicability and performance of the platform, instruments, and subsystems for making scientific measurements in support planetary science objectives. BOPPS carried two science instruments, BIRC and UVVis. BIRC is a cryogenic infrared multispectral imager which can image in the.6-5 m range using an HgCdTe detector. Narrow band filters were used to allow detection of water and CO2 emission features of the observed targets. The UVVis is an imager with the science range of 300 to 600 nm. A main feature of the UVVis instrument is the incorporation of a guide camera and a Fine Steering Mirror (FSM) system to reduce image jitter to less than 100 milliarcseconds. The BIRC instrument was used to image targets including Oort cloud comets Siding Spring and Jacques, and the dwarf planet 1 Ceres. BOPPS achieved the first ever earth based CO2 observation of a comet and the first images of water and CO2 of an Oort cloud comet (Jacques). It also made the first ever measurement of 1Ceres at 2.73 m to refine the shape of the infrared water absorption feature on that body. The UVVis instrument, mounted on its own optics bench, demonstrated the capability for image correction both from atmospheric disturbances as well as some of the residual motion from the gondola that was not addressed by the gondolas coarse pointing systems. The mission met its primary science and engineering objectives. The results of the BOPPS mission will feed into the body of science knowledge but also feed into future planning for more science from balloon-borne platforms. A notional platform called Gondola for High-Altitude Planetary Science (GHAPS) has been explored and this concept platform can address a number of important decadal questions. This paper provides a summary of the assessment of potential balloon borne observations for planetary science purposes including where potential science contributions can be expected, the necessary performance characteristics of the platform, and other features required or desired. The BOPPS mission is summarized including descriptions of the main elements and key science and engineering results. The paper then briefly describes GHAPS, and the salient features that can make it a valuable tool for future planetary observations.

Telescope↗
NASA NTRS2017

Long-term Neutron Background Environment Measured by the Dynamic Albedo of Neutrons (DAN) Instrument onboard Mars Science Laboratory (MSL)

The Dynamic Albedo of Neutrons (DAN) instrument onboard Mars Science Laboratory (MSL) consists of a pulsed neutron generator (PNG) and the neutron detector/electronics (DE) module. There are two 3He-proportional counters used in the DE module. One counter is surrounded with a Cd shell enclosure and measures epi-thermal neutrons with >0.4 eV. The second detector does not have a Cd shell enclosure and measures both thermal and epi-thermal neutrons. The main scientific objectives of DAN are two-fold: (1) the primary objective is to measure the bulk hydrogen abundance (in forms of water or hydrated minerals) of the sub-surface and (2) the secondary objective is to measure the background neutron environment at the surface. DAN achieves the first objective by using a pulsed 14 MeV neutron source (ACTIVE mode). Emitted neutrons undergo a series of nuclear interactions with the regolith and lose energy. The DAN DE module then measures the time profile of the neutrons returned from the regolith. Even a small amount of hydrogen, as low as 0.1 weight % in the regolith, can effectively moderate the high energy neutrons [Mitrofanov, et al., ]. The less-moderated (or epi-thermal) neutrons arrive at the detector earlier than the more-moderated (or thermal) neutrons. The shape and magnitude of neutron time profile curves after pulses can be used to estimate the depth distribution of the hydrogen content. When no neutron pulse is used (PASSIVE mode) DAN measures the neutron background environment at the Mars surface. There are two sources of the background neutrons which DAN would measure: one is secondary neutrons generated by galactic cosmic ray (GCR) interactions with atmospheric and surface materials and the other is neutrons from the Multi-Mission Radioisotope Thermoelectric Generator (MMRTG) onboard MSL as a power source. The passive mode data for the first 1300 sols of the MSL mission are presented in this paper. A summary of the DAN surface operation is described by [Mitrofanov et al., 2012; Jun et al., 2013.

Tate, C.↗
NASA NTRSDate not supplied

Production of Flight Instruments for Multi-Satellite Constellations

Recent National Academy of Science Decadal Surveys in space and Earth-science have called for simultaneous, distributed multi-point measurements in and from space, requiring constellations of small spacecraft. Small satellites have demonstrated their utility for enabling high-quality science measurements and observations. NASA missions have leveraged advances in sensor miniaturization, technology innovations, and new small satellite mission architectures to enable meaningful measurement-based scientific investigations that operate on small satellites and that are responsive to science objectives described in National Academy of Science Decadal Surveys. The advent of high capability small spacecraft enables consideration of science missions involving multiple small spacecraft, constellations of a few or many for simultaneous distributed in situ observations or remote observations from a variety of viewpoints. The central challenge for fielding instrumented space-flight constellations is to provide the required multiple sets of fully verified and calibrated instrument hardware, software, and operational processes from within a one-off project-based scientific space flight culture. Although there are numerous commercial entities providing “off-the shelf” spacecraft and avionics, the challenge lies in the multi-unit production of the uniquely targeted instrumentation necessary to perform the specific measurements required for a particular science investigation. Traditionally, the cost of such instrumentation has represented a significant portion of the hardware cost for a mission and posed the highest risk area for implementation. A shift in paradigm from large science platforms to constellations of smaller satellites drives the challenge to build instruments in a quasi-production environment. This paper describes key aspects of, and challenges encountered in the development program for the successful production of instruments for the Fast-Plasma Investigation (FPI) instrument suite of 64 flight plasma spectrometers and supporting electronics on the NASA Magnetospheric Multiscale (MMS) 4 satellite constellation mission. Although the MMS mission was not composed of small satellites, there are key aspects of the instrument production that apply directly to constellations of small satellites.

Arthur D Jacques↗
NASA NTRSDate not supplied

Production of Flight Instruments for Multi-Satellite Constellations

Recent National Academy of Science Decadal Surveys in space and Earth-science have called for simultaneous, distributed multi-point measurements in and from space, requiring constellations of small spacecraft. Small satellites have demonstrated their utility for enabling high-quality science measurements and observations. NASA missions have leveraged advances in sensor miniaturization, technology innovations, and new small satellite mission architectures to enable meaningful measurement-based scientific investigations that operate on small satellites and that are responsive to science objectives described in National Academy of Science Decadal Surveys. The advent of high capability small spacecraft enables consideration of science missions involving multiple small spacecraft, constellations of a few or many for simultaneous distributed in situ observations or remote observations from a variety of viewpoints. The central challenge for fielding instrumented space-flight constellations is to provide the required multiple sets of fully verified and calibrated instrument hardware, software, and operational processes from within a one-off project-based scientific space flight culture. Although there are numerous commercial entities providing “off-the shelf” spacecraft and avionics, the challenge lies in the multi-unit production of the uniquely targeted instrumentation necessary to perform the specific measurements required for a particular science investigation. Traditionally, the cost of such instrumentation has represented a significant portion of the hardware cost for a mission and posed the highest risk area for implementation. A shift in paradigm from large science platforms to constellations of smaller satellites drives the challenge to build instruments in a quasi-production environment. This paper describes key aspects of, and challenges encountered in the development program for the successful production of instruments for the Fast-Plasma Investigation (FPI) instrument suite of 64 flight plasma spectrometers and supporting electronics on the NASA Magnetospheric Multiscale (MMS) 4 satellite constellation mission. Although the MMS mission was not composed of small satellites, there are key aspects of the instrument production that apply directly to constellations of small satellites.

Arthur D Jacques↗
NASA NTRS2008

Jet Propulsion Laboratory: Annual Report 2007

Many milestones are celebrated in the business of space exploration, but one of them that arrived this year has particular meaning for us. Half a century ago, on January 31, 1958, the Jet Propulsion Laboratory was responsible for creating America's first satellite, Explorer 1, and joined with the Army to launch it into orbit. That makes 2007 the 50th year we have been sending robotic craft from Earth to explore space. No other event before or since has had such a profound effect on JPL's basic identity, setting it on the path to become the world's leader in robotic solar system exploration. It is not lost on historians that Explorer 1, besides being America's first satellite, was also the first spacecraft from any country to deliver scientific results in its case, the discovery of the Van Allen Radiation Belts that surround Earth. Science, of course, has been the prime motivator for all the dozens of missions that we have lofted into space in the half-century since then. JPL has sent spacecraft to every planet in the solar system from Mercury to Neptune, some of them very sophisticated machines. But in one way or another, they all owe their heritage to the 31-pound bullet-shaped probe JPL shot into space in 1958. Although we have ranged far and wide across the solar system, we have a very strong contingent of satellites and instruments dedicated, like Explorer, to the environment of our home planet. JPL missions have been providing much of the data to establish the facts of global warming - most especially, the melting of ice sheets in Greenland and Antarctica. During the past year, JPL and our parent organization, the California Institute of Technology, have created a task force to focus the special capabilities of the Laboratory and campus on ways to better understand the physics of global change. While Earth is a chaotic and dynamic system capable of large natural variations, evidence is mounting that human activities are playing an increasingly important role. A central piece of this effort is a search for novel energy sources to replace fossil fuels, the combustion of which adds carbon dioxide to our atmosphere. All of this is supported by our worldwide Deep Space Network, which provides the communication link between spacecraft and the ground. In addition, missions are infused with technologies developed by researchers working on projects for non-NASA sponsors as well as on pure research.

Jet Propulsion Laboratory (JPL)↗
NASA NTRS2004

The HYDROS Radiometer/Radar Instrument

The science objectives of the HYDROS mission are to provide frequent, global measurements of surface soil moisture and surface freeze/thaw state. In order to adequately measure these geophysical quantities, the key instrument requirements were determined by the HYDROS science team to be: 1) Dual-polarization L-Band passive radiometer measurements at 40 km resolution, 2) Dual-polarization L-Band active radar measurements at 3 km resolution, and 3) A wide swath to insure global three day refresh time for these measurements (1000 km swath at the selected orbit altitude of 670 km). As a solution to this challenging set of instrument requirements, a relatively large, 6 meter, conically-scanning reflector antenna architecture was selected for the instrument design. The deployable mesh antenna is shared by both the radiometer and radar electronics by employing a single L-Band feed.

freeze thaw↗
DOE OSTI2025

$\gamma$-ray angular correlations, distributions and linear polarization in tracking arrays

With $\gamma $-ray tracking arrays, the angular correlation and, especially, the linear polarization of $\gamma $ rays can be measured with high precision. However, because of the complexity of these spectrometers, measuring angular distributions is more involved. The techniques and associated formalisms were developed and established in the 1950s. The experimental setups of that era were relatively simple when compared to the advanced $\gamma $-ray tracking arrays available today. This paper aims to review and refine these techniques, unify the nomenclatures and, specifically, adapt them for use with the newest tracking arrays. In addition, new methods for producing the required response functions for these arrays are introduced.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2025

The XLZD Design Book: towards the next-generation liquid xenon observatory for dark matter and neutrino physics

This report describes the experimental strategy and technologies for XLZD, the next-generation xenon observatory sensitive to dark matter and neutrino physics. In the baseline design, the detector will have an active liquid xenon target of 60 tonnes, which could be increased to 80 tonnes if the market conditions for xenon are favorable. It is based on the mature liquid xenon time projection chamber technology used in current-generation experiments, LZ and XENONnT. The report discusses the baseline design and opportunities for further optimization of the individual detector components. The experiment envisaged here has the capability to explore parameter space for Weakly Interacting Massive Particle (WIMP) dark matter down to the neutrino fog, with a 3σ evidence potential for WIMP-nucleon cross sections as low as 3 x 10 –49 cm 2 (at 40 GeV/c 2 WIMP mass). The observatory will also have leading sensitivity to a wide range of alternative dark matter models. It is projected to have a 3σ observation potential of neutrinoless double beta decay of 136 Xe at a half-life of up to 5.7 x 10 27 years. Additionally, it is sensitive to astrophysical neutrinos from the sun and galactic supernovae.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
NASA NTRS1991

A mysterious plasma wave emission and the determination of plasma densities in Neptune's inner magnetosphere

One of the strongest plasma wave signals observed during the Voyager 2 encounter with Neptune is a narrowband emission between 3.0 and 4.3 kHz that was detected over a period of roughly 2 hours around closest approach. The emission occurs below the electron cyclotron frequency and the low-frequency cutoff of the radio continuum radiation. Of the naturally occurring signals in the earth's auroral zone and in Jupiter's magnetosphere this emission most resembles trapped Z mode waves found near the left-hand cutoff frequency. Using this identification, a plasma density profile is obtained that is independent of the plasma temperature. These densities greatly exceed those measured by the plasma science instrument on Voyager but are lower than estimates based on other models of Neptunian plasma wave phenomenology. If this wave mode is not a natural emission, it might arise from an unusual interaction of the spacecraft with the cold, dense ambient plasma.

Moses, S. L.↗
NASA NTRS1993

Nimbus-7 Total Ozone Mapping Spectrometer (TOMS) data products user's guide

Two tape products from the Total Ozone Mapping Spectrometer (TOMS) aboard the Nimbus-7 have been archived at the National Space Science Data Center. The instrument measures backscattered Earth radiance and incoming solar irradiance; their ratio -- the albedo -- is used in ozone retrievals. In-flight measurements are used to monitor changes in the instrument sensitivity. The algorithm to retrieve total column ozone compares the observed ratios of albedos at pairs of wavelengths with pair ratios calculated for different ozone values, solar zenith angles, and optical paths. The initial error in the absolute scale for TOMS total ozone is 3 percent, the one standard-deviation random error is 2 percent, and the drift is +/- 1.5 percent over 14.5 years. The High Density TOMS (HDTOMS) tape contains the measured albedos, the derived total ozone amount, reflectivity, and cloud-height information for each scan position. It also contains an index of SO2 contamination for each position. The Gridded TOMS (GRIDTOMS) tape contains daily total ozone and reflectivity in roughly equal area grids (110 km in latitude by about 100-150 km in longitude). Detailed descriptions of the tape structure and record formats are provided.

Mcpeters, Richard D.↗
NASA NTRS2000

The Mars Microprobe Mission: Advanced Micro-Avionics for Exploration Surface

The Mars Microprobe Mission is the second spacecraft developed as part of the New Millennium Program deep space missions. The objective of the Microprobe Project is to demonstrate the applicability of key technologies for future planetary missions by developing two probes for deployment on Mars. The probes are designed with a single stage entry, descent, and landing system and impact the Martian surface at speeds of approximately 200 meters per second. The microprobes are composed of two main sections, a forebody section that penetrates to a depth below the Martian surface of 0.5 to 2 meters, and an aftbody section that remains on the surface. Each probe system consists of a number of advanced technology components developed specifically for this mission. These include a non-erosive aeroshell for entry into. the atmosphere, a set of low temperature batteries to supply probe power, an advanced microcontroller to execute the mission sequence, collect the science data, and react to possible system fault conditions, a telecommunications subsystem implemented on a set of custom integrated circuits, and instruments designed to provide science measurements from above and below the Martian surface. All of the electronic components have been designed and fabricated to withstand the severe impact shock environment and to operate correctly at predicted temperatures below -100 C.

Blue, Randel↗
NASA NTRS2005

A Surface Science Paradigm for a Post-Huygens Titan Mission

With the Cassini-Huygens atmospheric probe drop-off mission fast approaching, it is essential that scientists and engineers start scoping potential follow-on surface science missions. This paper provides a summary of the first year of a two year design study which examines in detail the desired surface science measurements and resolution, potential instrument suite, and complete payload delivery system. Also provided are design concepts for both an aerial inflatable mobility platform and deployable instrument sonde. The tethered deployable sonde provides the capability to sample near surface atmosphere, sub-surface liquid (if it exists), and surface solid material. Actual laboratory tests of the amphibious sonde prototype are also presented.

Zimmerman, Wayne F.↗
NASA NTRS2006

Picometer Level Modeling of a Shared Vertex Double Corner Cube in the Space Interferometry Mission Kite Testbed

The Space Interferometry Mission (SIM) is a microarcsecond interferometric space telescope that requires picometer level precision measurements of its truss and interferometer baselines. Single-gauge metrology errors due to non-ideal physical characteristics of corner cubes reduce the angular measurement capability of the science instrument. Specifically, the non-common vertex error (NCVE) of a shared vertex, double corner cube introduces micrometer level single-gauge errors in addition to errors due to dihedral angles and reflection phase shifts. A modified SIM Kite Testbed containing an articulating double corner cube is modeled and the results are compared to the experimental testbed data. The results confirm modeling capability and viability of calibration techniques.

metrology↗
NASA NTRS2005

Jet Propulsion Laboratory: Annual Report 2004

Once or twice in an age, a year comes along that the historians proclaim as an Annus Mirabilis - a year of wonders. For the Jet Propulsion Laboratory, 2004 was just that sort of time. From beginning to end, it was a nonstop experience of wondrous events in space. Imagine that two robot rovers embark on cross-country rambles across Mars, scrutinizing rocks for signs of past water on the now-arid world. A flagship spacecraft brakes into orbit at Saturn to begin longterm surveillance of the ringed world, preparing to drop a sophisticated probe to the surface of its haze-shrouded largest moon. Another craft makes the closest-ever pass by the nucleus of a comet, collecting sample particles as it goes. Two new space telescopes peer into the depths of the universe far beyond our solar system, viewing stars, nebulas and galaxies in invisible light beyond the spectrum our eyes can see. A pair of instruments is lofted on a NASA Earth-orbiting satellite to monitor air quality and the protective layer of ozone blanketing our home planet. A small probe brings samples of the solar wind to Earth for in-depth study. While JPL was absorbed with all of these ventures on other worlds, NASA and the White House unveiled an ambitious new plan of space exploration. The Vision for Space Exploration announced in January foresees a program of robotic and astronaut missions leading to a human return to the Moon by 2020, and eventual crewed expeditions to Mars. The vision also calls for more robotic missions to the moons of the outer planets; spaceborne observatories that will search for Earth-like planets around other stars and explore the formation and evolution of the universe; and continued study of our home planet. In order to accomplish all of this, NASA must perfect many as-yet-uninvented technologies and space transportation capabilities. JPL has a great deal to bring to this vision. Robotic exploration of Mars will lead the way for missions that will carry women and men to the red planet. Our engineers and scientists are formulating spacecraft that could use nuclear power to enable exploration missions of the future. And even now we are designing formations of space telescopes that will capture family portraits of the planets around neighboring stars. Those are only some of the ways that the Laboratory is contributing to NASA's broader goals. During 2004, JPL made a distinctive contribution to agencywide initiatives in areas such as safety, NASA transformation, the agency's Internet portal and NASA's Explorer Schools programs. Years like 2004 pose a special challenge for us. It would be easy to say that this was a once-in-a-decade high point of mission activities, but I believe that this would miss an opportunity. We are fortunate to have many space projects in the works that have the promise of being just as exhilarating as the great mission successes that we celebrated this year. The challenge and opportunity for us now is to make every year like this one.

National Aeronautics and Space Administration (NAS↗