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All sourcesNASA NTRSDOE OSTI
NASA NTRS2006

NASA Balloon Technology Activities

The National Aeronautics and Space Administration (NASA) Balloon Program technology development efforts are fundamental to improving the capabilities of the balloon systems, better understanding of the flight dynamics, and to support the science missions throughout the next decade. Building on the foundations of the 20-year research and development program, a technology roadmap has been generated which identifies specific areas of interest to NASA and the vision of future developments. The major components of the roadmap are: vehicle systems, ballooncraft systems, operational and safety support systems, and planetary vehicles. Within each of these major components, technologies are targeted that will provide both better understanding and foster advancements. The Program's technology thrust areas are directed both in broad efforts that touch on a number of the major components as well as specific tasks that address elements within a specific component. Advances in vehicle systems have focused on producing better balloon designs. This is being attempted through the use of improved inputs into the ba!loon des@ process. Central to this is an increasing the understanding of materials used to fabricate balloons. Testing techniques have been improved with better bi-axial characterization of the balloon materials. More realistic radiative properties of the balloon films and components have also been made. Analytical assessments of the balloon designs are also key in improving balloon designs. These analytical assessments have been accomplished using improving analysis tools and an increased understanding of the float environment. Details of these improvements will be presented. To help improve the operational and flight safety of the balloons, improved flight performance predictions have been made using new analytical tools as well as incorporating the increased understanding of the float environment. These two have combined to allow for improved post-flight balloon performance correlations. A potential to significantly improve the potential safety of a long duration flight can be accomplished using some form of a trajectory modification system. An overview of the development efforts for a trajectory modification system will be presented. A number of efforts will be presented that are focused on the improvement of the ballooncraft systems. Planetary ballooning activities have benefited from a number of separate but related technology advancements made by the NASA Balloon Program's technology developments. The tools, techniques, and advancements made for balloon design and balloon analysis are directly applicable to the processes to develop planetary balloons for either Mars or Venus. An overview of the NASA Balloon Program's role in these efforts and testing will be presented. The technology roadmap, as well as specific projects and recent advancements, will be presented. This overview will demonstrate the technology advancements made by the NASA Balloon Program are focusing on leading balloon developments into the future.

Fairbrother, Debora A.↗
DOE OSTI2025

Giant Undulations Driven by Pitch‐Angle Scattering of Time Domain Structures Modulated by Plasmapause Surface Wave

Abstract Plasmapause surface waves (PSWs) near the plasmapause boundary are regarded to be the magnetospheric source of ionospheric auroral giant undulations (GUs) located at the equatorward boundary of diffuse aurora. However, the observational evidence of wave‐particle interaction connecting PSWs and GUs is absent. In this letter, we demonstrate GUs are driven by pitch‐angle scattering of time domain structures modulated by the PSWs, based on the conjugated ionospheric and magnetospheric observations. Specifically, ionospheric GUs are lighted by the pitch‐angle scattering of <1 keV thermal electron and ions and energetic ions with energy up to dozens of keV near the plasmapause. Further, the total fluxes during one PSW period and energy of scattered electron and ions determine the size and luminosity of GUs. Our research provides observational evidence that PSWs cause periodic electron precipitation via modulating the time domain structures rather than the previously predicted chorus or electron cyclotron harmonic waves.

Zhou, Yi‐Jia [Weihai Institute for Interdisciplina↗
DOE OSTI2018

High-pressure chemistry of hydrocarbons relevant to planetary interiors and inertial confinement fusion

Diamond formation in polystyrene (C8H8)n, which is laser-compressed and heated to conditions around 150 GPa and 5000 K, has recently been demonstrated in the laboratory [Kraus et al., Nat. Astron. 1, 606–611 (2017)]. Here, we show an extended analysis and comparison to first-principles simulations of the acquired data and their implications for planetary physics and inertial confinement fusion. Moreover, we discuss the advanced diagnostic capabilities of adding high-quality small angle X-ray scattering and spectrally resolved X-ray scattering to the platform, which shows great prospects of precisely studying the kinetics of chemical reactions in dense plasma environments at pressures exceeding 100 GPa.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
NASA NTRS1991

SHARP: Spacecraft Health Automated Reasoning Prototype

The planetary spacecraft mission OPS as applied to SHARP is studied. Knowledge systems involved in this study are detailed. SHARP development task and Voyager telecom link analysis were examined. It was concluded that artificial intelligence has a proven capability to deliver useful functions in a real time space flight operations environment. SHARP has precipitated major change in acceptance of automation at JPL. The potential payoff from automation using AI is substantial. SHARP, and other AI technology is being transferred into systems in development including mission operations automation, science data systems, and infrastructure applications.

Atkinson, David J.↗
NASA NTRS1993

Planetary protection issues for the MESUR mission: Probability of growth (Pg)

The purpose of the workshop was to re-evaluate the existing guidelines for the probability of growth of terrestrial organisms on Mars that were established by the National Academy of Sciences following the Viking Mission. A panel of specialists in microbiology and allied fields reviewed this issue in the light of current information about the physical and chemical environments expected on Mars. Their deliberations resulted in the virtually unanimous conclusion that the existing Pg guidelines were either appropriate or that the values for Pg should be further reduced. Individual assessments of this problem by each of the participants, together with those of additional invited experts are included.

Klein, Harold P.↗
NASA NTRS1993

Mesoscale characteristics of monsoonal convection and associated stratiform precipitation

Observations undertaken on 12 January 1990 at Darwin (Australia) are used to document the structure of a monsoonal rainband in a low convective available potential energy low-shear tropical environment. Dual-Doppler radar analyses are employed to investigate the structure and kinematics of the convective and stratiform regions. A system with the characteristics of a relatively short-lived squall line in which warm rain processes play a significant role in the production of precipitation is evident. Planetary boundary layer cold-pool production is important in the organization and motion of the system. A trailing stratiform region is evident with a mean updraft-downdraft circulation, but is composed of in situ decaying convective cells. A storm-relative mesoscale cyclonic circulation is also observed within the stratiform cloud. This vortex was maintained by thermodynamically induced midlevel convergence, convectively generated storm-scale circulations, and their interaction with the background monsoon flow.

Keenan, Thomas D.↗
NASA NTRS1998

Workshop on Using In Situ Resources for Construction of Planetary Outposts

The workshop examined the potential uses of indigenous materials on the Moon and Mars, other than those associated with the production of propellants for space transportation. The papers presented concerned the needs for construction, based on analysis of the current NASA Mars reference Mission and past studies studies of lunar outposts; the availability of materials on the Moon and Mars; construction techniques that make use of the natural environment; materials production and fabrication techniques based on indigenous materials; and new technologies that could promote the use of indigenous materials in construction.

M. B. Duke↗
NASA NTRS2001

Java PathExplorer: A Runtime Verification Tool

We describe recent work on designing an environment called Java PathExplorer for monitoring the execution of Java programs. This environment facilitates the testing of execution traces against high level specifications, including temporal logic formulae. In addition, it contains algorithms for detecting classical error patterns in concurrent programs, such as deadlocks and data races. An initial prototype of the tool has been applied to the executive module of the planetary Rover K9, developed at NASA Ames. In this paper we describe the background and motivation for the development of this tool, including comments on how it relates to formal methods tools as well as to traditional testing, and we then present the tool itself.

Havelund, Klaus↗
NASA NTRS1993

The Population of the Trans-Neptunian Region

The Pluto-Charon system orbits the Sun in the trans-Neptunian region, at the edge of the planetary system. Because of its location and relatively small mass, the Pluto-Charon binary is not capable of dynamically clearing its orbital zone of smaller objects. Thus, this zone is shared with two major cometary reservoirs, the Oort cloud and the Kuiper belt. This trans-Neptunian region environment is described.

Pluto Charon Oort Cloud Kuiper Belt Trans-Neptunia↗
NASA NTRS2008

Linear FMCW Laser Radar for Precision Range and Vector Velocity Measurements

An all fiber linear frequency modulated continuous wave (FMCW) coherent laser radar system is under development with a goal to aide NASA s new Space Exploration initiative for manned and robotic missions to the Moon and Mars. By employing a combination of optical heterodyne and linear frequency modulation techniques and utilizing state-of-the-art fiber optic technologies, highly efficient, compact and reliable laser radar suitable for operation in a space environment is being developed. Linear FMCW lidar has the capability of high-resolution range measurements, and when configured into a multi-channel receiver system it has the capability of obtaining high precision horizontal and vertical velocity measurements. Precision range and vector velocity data are beneficial to navigating planetary landing pods to the preselected site and achieving autonomous, safe soft-landing. The all-fiber coherent laser radar has several important advantages over more conventional pulsed laser altimeters or range finders. One of the advantages of the coherent laser radar is its ability to measure directly the platform velocity by extracting the Doppler shift generated from the motion, as opposed to time of flight range finders where terrain features such as hills, cliffs, or slopes add error to the velocity measurement. Doppler measurements are about two orders of magnitude more accurate than the velocity estimates obtained by pulsed laser altimeters. In addition, most of the components of the device are efficient and reliable commercial off-the-shelf fiber optic telecommunication components. This paper discusses the design and performance of a second-generation brassboard system under development at NASA Langley Research Center as part of the Autonomous Landing and Hazard Avoidance (ALHAT) project.

Pierrottet, Diego↗
NASA NTRS2012

Revitalization of the NASA Langley Research Center's Infrastructure

The NASA Langley Research Center (Langley) was founded in 1917 as the nation's first civilian aeronautical research facility and NASA's first field center. For nearly 100 years, Langley has made significant contributions to the Aeronautics, Space Exploration, and Earth Science missions through research, technology, and engineering core competencies in aerosciences, materials, structures, the characterization of earth and planetary atmospheres and, more recently, in technologies associated with entry, descent, and landing. An unfortunate but inevitable outcome of this rich history is an aging infrastructure where the longest serving building is close to 80 years old and the average building age is 44 years old. In the current environment, the continued operation and maintenance of this aging and often inefficient infrastructure presents a real challenge to Center leadership in the trade space of sustaining infrastructure versus not investing in future capabilities. To address this issue, the Center has developed a forward looking revitalization strategy that ties future core competencies and technical capabilities to the Center Master Facility Plan to maintain a viable Center well into the future. This paper documents Langley's revitalization strategy which integrates the Center's missions, the Langley 2050 vision, the Center Master Facility Plan, and the New Town repair-by-replacement program through the leadership of the Vibrant Transformation to Advance Langley (ViTAL) Team.

Weiser, Erik S.↗
NASA NTRS2018

The Martian Magnetosphere: Areas of Unsettled Terminology

The near-Mars space environment has a number of regions and boundaries that have numerous and confusing labels. The whole region is sometimes referred to as the induced Martian magnetosphere and sometimes as the solar wind interaction with Mars. The middle boundary where the shocked solar wind plasma gives way to predominately planetary-derived plasma has a variety of names. The region below that middle boundary and the top of the ionosphere also does not have a uniformly used name. There are several other regions and boundaries that also have naming confusion. The various terms that are currently used in the literature for these subjects are identified and discussed; regions and boundaries that have well-settled names are not discussed nor are the details of the physics involved.

Magnetosphere↗
NASA NTRS2022

Microbial Life in Space

Outer space is a harsh environment harbouring multiple forms of stress like cosmic radiation, space vacuum, extreme temperature and pressure, UV radiations, and altered gravity. Earth’s atmosphere has several layers that expose microbial and terrestrial life to harsh external environments. In order to study the limits of survival of microbial life in extremes, it is imperative to study the response of micro-organisms to space-related stress. The present chapter summarizes the various balloon and flight experiments performed to investigate the presence and response of microbial life in space. Studying the microbiome in the ISS is important as pathogenic bacteria can present a major risk to astronaut health in a closed environment. Hence, studying occurrence, ecology, diversity, response, and adaptations of microbial life in space is crucial to understanding the limits of organismic survival in inhospitable conditions. Studying microbial life in space also helps predict the plausible survival and endurance of microbial travel between planets, crucial to lithopanspermia theories and planetary protection.

space↗
NASA NTRSDate not supplied

The Mars 2020 Watson Imaging Subsystem of the Sherloc Investigation and Anticpated Early Results

In February 2021, the Mars 2020 Perseverance rover is anticipated to touch down in Jezero crater, Mars. Perseverance is unique in that it will conduct in situ science as well as cache samples for eventual return to Earth for analysis in terrestrial laboratories. It will explore the geologic setting within Jezero over a range of scales in order to address fundamental questions about the evolution of Mars and assess whether there is evidence of past or present Martian life. The Wide Angle Topographic Sensor for Operations and eNgineering (WATSON), one of two imaging subsystems within the Scanning Habitable Environments with Raman and Luminescence for Organics and Chemicals (SHERLOC) instrument[1,2], acquires images that support scientific study of Jezero crater and sample acquisition, as well as rover and instrument operations(Fig. 1).WATSON serves a number of roles; it 1) provides color context imaging of SHERLOC and Planetary Instrument for X-Ray Litho chemistry (PIXL)analysis locations, placing the spatial distribution of organics and mineralogy detected by SHERLOC and the elemental maps generated by PIXL within the context of rock texture and structure; 2)acquires stand-alone observations of rock structures and textures from the outcrop to the grain scale; and 3)images rover components and other instruments to monitor their health and condition. We plan to present images acquired within the first ~30 sols of operations.

M E Minitti↗
NASA NTRS2020

An evolutionary system of mineralogy. Part II: Interstellar and solar nebula primary condensation mineralogy (>4.565 Ga)

The evolutionary system of mineralogy relies on varied physical and chemical attributes, including trace elements, isotopes, solid and fluid inclusions, and other information-rich characteristics, to understand processes of mineral formation and to place natural condensed phases in the deep-time context of planetary evolution. Part I of this system reviewed the earliest refractory phases that condense at T > 1000 K within the turbulent expanding and cooling atmospheres of highly evolved stars. Part II considers the subsequent formation of primary crystalline and amorphous phases by condensation in three distinct mineral-forming environments, each of which increased mineralogical diversity and distribution prior to the accretion of planetesimals >4.5 billion years ago. (1) Interstellar molecular solids: Varied crystalline and amorphous molecular solids containing primarily H, C, O, and N are observed to condense in cold, dense molecular clouds in the interstellar medium (10 < T < 20 K; P < 10−13 atm). With the possible exception of some nanoscale organic condensates preserved in carbonaceous meteorites, the existence of these phases is documented primarily by telescopic observations of absorption and emission spectra of interstellar molecules in radio, microwave, or infrared wavelengths. (2) Nebular and circumstellar ice: Evidence from infrared observations and laboratory experiments suggest that cubic H2O (“cubic ice”) condenses as thin crystalline mantles on oxide and silicate dust grains in cool, distant nebular and circumstellar regions where T ~100 K. (3) Primary condensed phases of the inner solar nebula: The earliest phase of nebular mineralogy saw the formation of primary refractory minerals that solidified through high-temperature condensation (1100 < T < 1800 K; 10−6 < P < 10−2 atm) in the solar nebula more than 4.565 billion years ago. These earliest mineral phases originating in our solar system formed prior to the accretion of planetesimals and are preserved in calcium-aluminum-rich inclusions, ultra-refractory inclusions, and amoeboid olivine aggregates.

Shaunna M. Morrison↗
NASA NTRS2017

Measuring Surface Bulk Elemental Composition on Venus

The extreme surface environment (462 C, 93 bars pressure) of Venus makes subsurface measurements of its bulk elemental composition extremely challenging. Instruments landed on the surface of Venus must be enclosed in a pressure vessel. The high surface temperatures also require a thermal control system to keep the instrumentation temperatures within their operational range for as long as possible. Since Venus surface probes can currently operate for only a few hours, it is crucial that the lander instrumentation be able to make statistically significant measurements in a short time. An instrument is described that can achieve such a measurement over a volume of thousands of cubic centimeters of material by using high energy penetrating neutron and gamma radiation. The instrument consists of a Pulsed Neutron Generator (PNG) and a Gamma-Ray Spectrometer (GRS). The PNG emits isotropic pulses of 14.1 MeV neutrons that penetrate the pressure vessel walls, the dense atmosphere and the surface rock. The neutrons induce nuclear reactions in the rock to produce gamma rays with energies specific to the element and nuclear process involved. Thus the energies of the detected gamma rays identify the elements present and their intensities provide the abundance of each element. The GRS spectra are analyzed to determine the Venus elemental composition from the spectral signature of individual major, minor, and trace radioactive elements. As a test of such an instrument, a Schlumberger Litho Scanner oil well logging tool was used in a series of experiments at NASA's Goddard Space Flight Center. The Litho Scanner tool was mounted above large (1.8 m x 1.8 m x.9 m) granite and basalt monuments and made a series of one-hour elemental composition measurements in a planar geometry more similar to a planetary lander measurement. Initial analysis of the results shows good agreement with target elemental assays

Venus↗
NASA NTRSDate not supplied

ANALYSIS OF THE MSL/MEDLI ENTRY DATA WITH COUPLED CFD AND MATERIAL RESPONSE.

The Mars Science Laboratory (MSL) was protected during its atmospheric entry by an instrumented heat-shield using NASA's Phenolic Impregnated Carbon Ablator (PICA) material. PICA is a lightweight carbon fiber/polymeric resin material that offers out-standing performances for protecting probes during planetary entry. The Mars Entry Descent and Landing Instrument (MEDLI) suite on MSL offers unique in-flight validation data for models of material response and atmospheric entry. MEDLI recorded, among other things, time-resolved in-depth temperature data of PICA using thermocouple sensors assembled in the MEDLI Integrated Sensor Plugs (MISP). The objective of this work is to showcase and analyze the coupling between the material response and the aerothermal environment. As shown in Figure 1, the workflow is divided into the following steps. First, the aerothermal properties are computed in the Data Parallel Line Relaxation (DPLR) code [3] and used with the Nonequilibrium air radiation (NEQAIR) program [8] to compute radiative heating. Second, the thermal response inside the material is computed in the Porous material Analysis Toolbox based on Open-FOAM (PATO) using a fixed blowing correction parameter. Third, the pyrolysis gases computed in PATO are used as inputs to a blowing boundary condition within DPLR. Fourth, the new environment properties from DPLR are used in NEQAIR to provide an updated solution, then both the updated aerothermal environment and radiative heating are used in PATO without blowing correction. The third and fourth steps are then repeated until convergence in surface temperature is obtained. Convergence in the radiative heating is generally achieved before surface temperature, at which point the radiative heating is no longer updated. Char mass loss rates are forced to zero to produce a non-receding surface condition. For early time points in the trajectory, where flow around the MSL aeroshell is rarefied, the Direct Simulation Monte Carlo (DSMC) code, SPARTA, is used to compute the aerothermal environment. Iteration between PATO and SPARTA is not performed due to the computational cost of DSMC simulations. Preliminary results of the coupling between PATO and DPLR for the MSL heatshield atmospheric entry model are presented in Figures 2-4 at 65 seconds after entry interface. Figure 2 shows the surface temperature results from an uncoupled simulation in PATO with the blowing correction parameter applied (left) along with the coupled surface temperature after iteration (right). Figure 3 shows the surface temperature along the centerline from windward to leeward for easier comparison. Figure 4 shows the coupled and uncoupled pyrolysis gas blowing rate. Mars 2020 used a similar heatshield consisting of PICA for thermal protection during entry, descent, and landing. In preparation for Mars 2020 post-flight analysis, the predictive material response capability is benchmarked against flight data from MEDLI. This work represents an important milestone toward the development of validated predictive capabilities for designing thermal protection systems for planetary probes.

Mars Science Laboratory↗
NASA NTRS1991

The Galileo Venus encounter

Galileo's instruments obtained a broad range of planetary measurements during the spacecraft's Venus encounter on February 10, 1990. The instrumentation brought to bear encompassed UV spectra, limb haze studies, and particles-and-fields experiments. These data, in conjunction with ground-based observations conducted during the encounter, have yielded accurate information on the Venus plasma environment, cloud patterns, and the possibility of interpreting certain impulsive events as lightning.

Johnson, Torrence V.↗