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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 NTRS1993

Particle kinetic simulation of high altitude hypervelocity flight

In this grant period, the focus has been on enhancement and application of the direct simulation Monte Carlo (DSMC) particle method for computing hypersonic flows of re-entry vehicles. Enhancement efforts dealt with modeling gas-gas interactions for thermal non-equilibrium relaxation processes and gas-surface interactions for prediction of vehicle surface temperatures. Both are important for application to problems of engineering interest. The code was employed in a parametric study to improve future applications, and in simulations of aeropass maneuvers in support of the Magellan mission. Detailed comparisons between continuum models for internal energy relaxation and DSMC models reveals that several discrepancies exist. These include definitions of relaxation parameters and the methodologies for implementing them in DSMC codes. These issues were clarified and all differences were rectified in a paper (Appendix A) submitted to Physics of Fluids A, featuring several key figures in the DSMC community as co-authors and B. Haas as first author. This material will be presented at the Fluid Dynamics meeting of the American Physical Society on November 21, 1993. The aerodynamics of space vehicles in highly rarefied flows are very sensitive to the vehicle surface temperatures. Rather than require prescribed temperature estimates for spacecraft as is typically done in DSMC methods, a new technique was developed which couples the dynamic surface heat transfer characteristics into the DSMC flow simulation code to compute surface temperatures directly. This model, when applied to thin planar bodies such as solar panels, was described in AIAA Paper No. 93-2765 (Appendix B) and was presented at the Thermophysics Conference in July 1993. The paper has been submitted to the Journal of Thermophysics and Heat Transfer. Application of the DSMC method to problems of practical interest requires a trade off between solution accuracy and computational expense and limitations. A parametric study was performed and reported in AIAA Paper No. 93-2806 (Appendix C) which assessed the accuracy penalties associated with simulations of varying grid resolution and flow domain size. The paper was also presented at the Thermophysics Conference and will be submitted to the journal shortly. Finally, the DSMC code was employed to assess the pitch, yaw, and roll aerodynamics of the Magellan spacecraft during entry into the Venus atmosphere at off-design attitudes. This work was in support of the Magellan aerobraking maneuver of May 25-Aug. 3, 1993. Furthermore, analysis of the roll characteristics of the configuration with canted solar panels was performed in support of the proposed 'Windmill' experiment. Results were reported in AIAA Paper No. 93-3676 (Appendix D) presented at the Atmospheric Flight Mechanics Conference in August 1993, and were submitted to Journal of Spacecraft and Rockets.

Haas, Brian L.↗

NASA NTRS1979

X-ray spectrometer spectrograph telescope system

A new sounding rocket payload that has been developed for X-ray spectroscopic studies of the solar corona is described. The instrument incorporates a grazing incidence Rowland mounted grating spectrograph and an extreme off-axis paraboloic sector feed system to isolate regions of the sun of order 1 x 10 arc seconds in size. The focal surface of the spectrograph is shared by photographic and photoelectric detection systems, with the latter serving as a part of the rocket pointing system control loop. Fabrication and alignment of the optical system is based on high precision machining and mechanical metrology techniques. The spectrograph has a resolution of 16 milliangstroms and modifications planned for future flights will improve the resolution to 5 milliangstroms, permitting line widths to be measured.

Bruner, E. C., Jr.↗

NASA NTRS1990

Attitude sensor alignment calibration for the solar maximum mission

An earlier heuristic study of the fine attitude sensors for the Solar Maximum Mission (SMM) revealed a temperature dependence of the alignment about the yaw axis of the pair of fixed-head star trackers relative to the fine pointing Sun sensor. Here, new sensor alignment algorithms which better quantify the dependence of the alignments on the temperature are developed and applied to the SMM data. Comparison with the results from the previous study reveals the limitations of the heuristic approach. In addition, some of the basic assumptions made in the prelaunch analysis of the alignments of the SMM are examined. The results of this work have important consequences for future missions with stringent attitude requirements and where misalignment variations due to variations in the temperature will be significant.

Pitone, Daniel S.↗

NASA NTRS2011

Vehicle Shield Optimization and Risk Assessment for Future Human Space Missions

As the focus of future human space missions shifts to destinations beyond low Earth orbit such as Near Earth Objects (NEO), the moon, or Mars, risks associated with extended stay in hostile radiation environment need to be well understood and assessed. Since future spacecrafts designs and shapes are evolving continuous assessments of shielding and radiation risks are needed. In this study, we use a predictive software capability that calculates risks to humans inside a spacecraft prototype that builds on previous designs. The software uses CAD software Pro/Engineer and Fishbowl tool kit to quantify radiation shielding provided by the spacecraft geometry by calculating the areal density seen at a certain point, dose point, inside the spacecraft. Shielding results are used by NASA-developed software, BRYNTRN, to quantify organ doses received in a human body located in the vehicle in case of solar particle event (SPE) during such prolonged space missions. Organ doses are used to quantify risks on astronauts health and life using NASA Space Cancer Model. The software can also locate shielding weak points-hotspots-on the spacecraft s outer surface. This capability is used to reinforce weak areas in the design. Results of shielding optimization and risk calculation on an exploration vehicle design for missions of 6 months and 30 months are provided in this study. Vehicle capsule is made of aluminum shell that includes main cabin and airlock. The capsule contains 5 sets of racks that surround working and living areas. Water shelter is provided in the main cabin of the vehicle to enhance shielding in case of SPE.

Nounu, Hatem N.↗

NASA NTRS2020

Compass Final Report: Venus Bridge Orbiter and Surface Study (V-BOSS)

The Venus Bridge Orbiter and Surface Study (V-BOSS) Compass concurrent engineering design team study shows that new, high-priority Venus science can be achieved using a linked Orbiter + Surface Element (Lander) mission concept within a $200M cost cap with assumptions. This is feasible through optimizing investment in early technologies and platforms, such as the Long-Lived In-Situ Solar System Explorer (LLISSE), leveraging known and flight-ready technology, and the overall use of simple, small, robust systems in innovative approaches to Venus exploration. This architecture allows a range of science investigations through modification of Orbiter-Lander platforms in this study through choice of other instruments (often sensors), science themes, or operational modes. In particular, a fundamental strength of this approach is to provide science not available in other ways by using simplified architectures including rugged systems operable in-situ on the Venus surface. Such investigations would be pathfinders for more complex, and more expensive, future missions. Additionally, the results of this study can be used to further champion the need, value and return of early investment technology programs for the hard problem of in-situ investigations at Venus.

Venus Bridge↗

NASA NTRS1984

Detailed studies of the dynamics and energetics of coronal bullets

Coronal bullets are small ejecta of cool, dense plasma observed to accelerate through the solar atmosphere from 20 to 450 km/s. The NRL Dynamic Flux Tube Model has been used to simulate the evolving physical properties of these dynamic events. The present calculations utilize an adaptive-gridding technique to resolve the fine structure within and around the bullets. In this work, an identification was made of a component of shocked plasma which piles up ahead of the bullet and eventually dominates both the dynamics and heating of the original bullet mass. The observational consequences of this shocked component are discussed in terms of the available HRTS EUV data, and suggestions are made for optimizing future observations of this phenomenon. An investigation has also been conducted of the structure of the bullet material visible in EUV spectral lines and the observable characteristics of the EUV-emitting plasma. Finally, the most likely mechanisms for accelerating the bullets, as well as favorable sites of origin are evaluated.

Karpen, J. T.↗

NASA NTRS1974

Electric propulsion - Past history and future prospects

Studies of feasibility and flight mechanics of electric propulsion systems began around 1946. Conceptual systems design started in 1954, experimental developments in 1958; flight tests in 1964 and 1970 proved the functioning of electric thrusters in space. Further development of ion thruster systems has concentrated on bombardment ionization in the U.S., and on radiofrequency, bombardment, and surface contact ionization in West Germany, Great Britain, France and Russia. Electrothermal, plasma, and colloid thruster development has been pursued in many contries. Electric thrusters were used successfully during past years for satellite attitude control, and for prime propulsion of the Russian spacecraft Yantar. Further applications for attitude and position control of satellites are planned. Studies are presently underway for solar electric missions to planets, planetary moons, comets, asteroids, and toward the sun, and also for missions in near-earth space involving transfer, servicing, and repair of orbiting spacecraft.

Stuhlinger, E.↗

NASA NTRS1975

Hydrogen energy systems technology study

The paper discusses the objectives of a hydrogen energy systems technology study directed toward determining future demand for hydrogen based on current trends and anticipated new uses and identifying the critical research and technology advancements required to meet this need with allowance for raw material limitations, economics, and environmental effects. Attention is focused on historic production and use of hydrogen, scenarios used as a basis for projections, projections of energy sources and uses, supply options, and technology requirements and needs. The study found more than a billion dollar annual usage of hydrogen, dominated by chemical-industry needs, supplied mostly from natural gas and petroleum feedstocks. Evaluation of the progress in developing nuclear fusion and solar energy sources relative to hydrogen production will be necessary to direct the pace and character of research and technology work in the advanced water-splitting areas.

Kelley, J. H.↗

NASA NTRS1989

The Atmospheric Tides Middle Atmosphere Program (ATMAP)

Atmospheric tides, oscillations in meteorological fields occurring at subharmonics of a solar or lunar day, comprise a major component of middle atmosphere global dynamics. The purpose of the 1982 to 1986 Atmospheric Tides Atmosphere Program (ATMAP) was to foster an interaction between experimentalists, data analysts, and theoreticians and modelers, in order to better understand the physical mechanisms governing tides and their relationships to other scales of motion, and to thereby explain features of observed tidal structures in the mesosphere and lower thermosphere. The ATMAP consisted of seven observational campaigns, five workshops and a climatological study. A historical perspective is provided along with a summary of major results, conclusions, and recommendations for future study which have emerged from the ATMAP.

Forbes, J. M.↗

NASA NTRSDate not supplied

Understanding the Chemistry of PAHs in H2O Ice

Polycyclic aromatic hydrocarbons (PAHs) can be incorporated into H O ice grains and mantles found in dense molecular clouds, comets, interplanetary dust particles (IDPs), and many Solar System objects. However, laboratory infrared (IR) spectroscopic studies of PAHs in ices is still a relatively young field. Early research efforts have shown the rich chemistry of PAHs in H O to be dependent on PAH concentration, with the concentration impacting everything from IR band shifts to the photoproducts produced [1-6]. Similarly, research suggests that a potential top-down synthesis route for complex organic molecules or COMs found within solar systems is possible from PAHs in water ice [7]. In order to fully exploit the observations from the James Webb Space Telescope (JWST) more IR studies of PAHs in H O ice under relevant astrophysical conditions and planetary systems are needed. The NASA ICEE (Institute for Carbon Evolution Experiments), formerly the NASA Ames PAH IR Laboratory, has been at the forefront of this field. Starting in 2019, just before the COVID-19 shutdown, the ICEE laboratory underwent a major renovation, gearing it towards in-depth PAHs in H O ice research under relevant solar systems and interstellar conditions. The ICEE facility enables us to study the processing of PAHs in H O ice using UV photons and charged particle (electron) irradiation either singly or in combination under ultra-high vacuum and low temperature (15K). We use in-situ measurements with IR, Raman, and mass spectra by which we monitor the chemistry of PAHs in H O ice before, during and after the irradiation. This presentation will summarize the past work regarding PAHs in ices and provide an update on the latest ICEE research results in this area, outlining a roadmap for future research efforts.

Andrew Mattioda↗

NASA NTRS2025

Beamed Energy and Communications Optical Node (BEACON) Demonstrator

Due to long shadow periods (2 weeks or greater) on the south pole, concepts to raise solar arrays to a sufficient height at specific locations have shown the capability to provide power to surface users for much longer periods. Such a tower can also provide a 3rd Generation Partnership Project (3GPP) service for users up to 10 km away, dependent on terrain. An option to deliver power, albeit with low efficiency, using a laser beam coupled with the tower height could provide mobile and fixed users power during darkness, reducing their battery requirements. A demonstration of these technologies in the lunar environment is crucial to support future Artemis campaigns as well as potential emerging lunar infrastructures. A demonstrator design of a 15 m deployed boomon the south pole has been shown to enable both the gathering of kilowatts of power and the provision of 3GPP relay and backhaul given an appropriate lunar location. Using a laser to send power to a photovoltaic receiver has been proposed to transmit electrical power on the moon, particularly for applications such as powering a rover in near-polar permanently shadowed regions (PSR) where solar power is not available. In this work, the Compass team performed a conceptual engineering design study of a near-term laser surface-to-surface power beaming and relay station using a tower to simultaneously carry the power source (Vertical Solar Array Technologies (VSAT)[1]), the 3GPP relay antenna, and the laser telescope.

Deployable solar array tower laser beamed power 3G↗

NASA NTRSDate not supplied

Beamed Energy and Communications Optical Node (BEACON) Demonstrator

Lunar Relay↗

NASA NTRS1990

Astronomical observations with normal incidence multilayer optics - Recent results and future prospects

High-resolution X-ray and EUV images of the solar corona have been obtained with two rocket-borne normal incidence Cassegrain multilayer telescopes. The Cassegrain images correspond to material at about 10 to the 6th K and about 80,000 K. Other images, at somewhat lower resolution, were obtained with Herschelian multilayer telescopes and Wolter-Schwarzschild hybrid grazing incidence/multilayer optical systems. The Cassegrain and Herschelian images are discussed emphasizing the analysis of polar plumes observed at the limb of the sun. The application of specific multilayer techniques to astronomical observations is discussed, emphasizing observations of the sun. Current efforts to develop a comprehensive Multi-Spectral Solar Telescope Array rocket instrument for the study of a wide variety of problems related to the solar atmosphere are reported.

Walker, Arthur B. C., Jr.↗

NASA NTRSDate not supplied

Photon Harvesting and Rocky Planet Biosignatures with 3D Climate Models

On the Earth solar photons are collected, sifted, and harvested by life at a scale that has transformed and defined the planet and continues to do so. That transformation is considered to be a key biosignature to look for in the rocky exoplanet population of our galaxy. However, the availability of photons on planetary surfaces depends on orbital and spin configuration as well as shadowing and scattering by clouds and other atmospheric phenomena. We are using a state-of-the-art 3D climate model (ROCKE-3D, Way et al. 2017) to study rocky planet surface irradiances and the implications for biosignatures and future missions such as the Habitable Worlds Observatory.

exoplanets↗

NASA NTRS2011

Heavy Lift Launch Capability with a New Hydrocarbon Engine (NHE)

The Advanced Concepts Office (ACO) at NASA Marshall Space Flight Center has analyzed over 2000 Ares V and other heavy lift concepts in the last 3 years. These concepts were analyzed for Lunar Exploration Missions, heavy lift capability to Low Earth Orbit (LEO) as well as exploratory missions to other near earth objects in our solar system. With the pending retirement of the Shuttle fleet, our nation will be without a civil heavy lift launch capability, so the future development of a new heavy lift capability is imperative for the exploration and large science missions our Agency has been tasked to deliver. The majority of the heavy lift concepts analyzed by ACO during the last 3 years have been based on liquid oxygen / liquid hydrogen (LOX/LH2) core stage and solids booster stage propulsion technologies (Ares V / Shuttle Derived and their variants). These concepts were driven by the decisions made from the results of the Exploration Systems Architecture Study (ESAS), which in turn, led to the Ares V launch vehicle that has been baselined in the Constellation Program. Now that the decision has been made at the Agency level to cancel Constellation, other propulsion options such as liquid hydrocarbon fuels are back in the exploration trade space. NASA is still planning exploration missions with the eventual destination of Mars and a new heavy lift launch vehicle is still required and will serve as the centerpiece of our nation s next exploration architecture s infrastructure. With an extensive launch vehicle database already developed on LOX/LH2 based heavy lift launch vehicles, ACO initiated a study to look at using a new high thrust (> 1.0 Mlb vacuum thrust) hydrocarbon engine as the primary main stage propulsion in such a launch vehicle.

Threet, Grady E., Jr.↗

NASA NTRS2012

Assessment of DSN Communication Coverage for Space Missions to Potentially Hazardous Asteroids

A communication coverage gap exists for Deep Space Network (DSN) antennas. This communication coverage gap is on the southern hemisphere, centered at approximate latitude of -47deg and longitude of -45deg. The area of this communication gap varies depending on the altitude from the Earth s surface. There are no current planetary space missions that fall within the DSN communication gap because planetary bodies in the Solar system lie near the ecliptic plane. However, some asteroids orbits are not confined to the ecliptic plane. In recent years, Potentially Hazardous Asteroids (PHAs) have passed within 100,000 km of the Earth. NASA s future space exploration goals include a manned mission to asteroids. It is important to ensure reliable and redundant communication coverage/capabilities for manned space missions to dangerous asteroids that make a sequence of close Earth encounters. In this paper, we will describe simulations performed to determine whether near-Earth objects (NEO) that have been classified as PHAs fall within the DSN communication coverage gap. In the study, we reviewed literature for a number of PHAs, generated binary ephemeris for selected PHAs using JPL s HORIZONS tool, and created their trajectories using Satellite Took Kit (STK). The results show that some of the PHAs fall within DSN communication coverage gap. This paper presents the simulation results and our analyses

Kegege, Obadiah↗

NASA NTRSDate not supplied

Beyond Low-Earth Orbit: Characterizing Immune and microRNA Differentials Following Simulated Deep Spaceflight Conditions in Mice

Spaceflight missions can cause immune system dysfunction in astronauts with little understanding of immune outcomes in deep space. This study assessed immune responses in mice following ground-based, simulated deep spaceflight conditions, compared to data from astronauts on ISS missions. For ground studies, we simulated microgravity using the hindlimb unloaded mouse model alone or in combination with acute simulated galactic cosmic rays or solar particle events irradiation. Immune profiling results revealed unique immune diversity following each experimental condition, suggesting each stressor results in distinct circulating immune responses, with clear consequences for deep spaceflight. Circulating plasma microRNA sequence analysis revealed involvement in immune system dysregulation. Furthermore, a large astronaut cohort showed elevated inflammation during LEO missions, thereby supporting our simulated ground experiments in mice. Herein, circulating immune biomarkers are defined by distinct deep space irradiation types coupled to simulated microgravity and could be targets for future space health initiatives.

deep spaceflight stressors↗

NASA NTRS1986

Astrophysics

The instrumentation, accomplishments and future activities in space astrophysics observations are explored. The Solrad, Orbiting Solar Observatory, Solar Maximum Mission, Orbiting Astronomical Observatory, Extreme Ultraviolet Explorer, Uhuru, HEAO-2, IRAS and ESA SAS spacecraft missions and data are summarized. Observations which identified the black hole in Cygnus-1 are described and known gravity-controlled phenomena in the universe are reviewed. Observations at different electromagnetic wavelengths and by particle detectors are outlined, and proposed gravity wave and neutrino detectors are discussed. The implications of the angular, spectral and temporal resolution, polarization, spectral range and observational limits of the instrumentation and data are considered. Current topics of interest in studies of the cosmic background radiation, distance scales, quasars and pulsars, star formation, and coronal heating are outlined. Finally, the design features and observational goals of the NASA Great Observatories space platforms are described.

Gilman, David A.↗