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383
Jun 11, 2011
06/11
by
Adams, Charles L
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The NASA In-Space Propulsion Technology (ISPT) Projects Office has been sponsoring 2 solar sail system design and development hardware demonstration activities over the past 20 months. Able Engineering Company (AEC) of Goleta, CA is leading one team and L Garde, Inc. of Tustin, CA is leading the other team. Component, subsystem and system fabrication and testing has been completed successfully. The goal of these activities is to advance the technology readiness level (TRL) of solar sail...
Topics: FLOW DISTRIBUTION, RADIATIVE HEAT TRANSFER, APPLICATIONS PROGRAMS (COMPUTERS), THREE DIMENSIONAL...
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394
May 27, 2011
05/11
by
Agrawal, Govind P.; Goorjian, Peter M
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The main objective of the Joint-Research Interchange NCC2-5149 was to develop computer codes for accurate simulation of femtosecond pulse propagation in semiconductor lasers and semiconductor amplifiers [I]. The code should take into account all relevant processes such as the interband and intraband carrier relaxation mechanisms and the many-body effects arising from the Coulomb interaction among charge carriers [2]. This objective was fully accomplished. We made use of a previously developed...
Topics: MARS (PLANET), VARIABILITY, THERMOSPHERE, TEMPORAL DISTRIBUTION, SPATIAL DISTRIBUTION, HIGH...
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155
Sep 20, 2010
09/10
by
Bailor, Paul D.; Luginbuhl, David R.; Robinson, John S
texts
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This paper describes a domain-specific software design system based on the concepts of software architectures engineering and domain-specific models and languages. In this system, software architectures are used as high level abstractions to formulate a domain-specific software design. The software architecture serves as a framework for composing architectural fragments (e.g., domain objects, system components, and hardware interfaces) that make up the knowledge (or model) base for solving a...
Topics: LUNAR EXPLORATION, PROPULSION SYSTEM CONFIGURATIONS, SOLAR ARRAYS, LUNAR ROVING VEHICLES, LUNAR...
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268
Jul 12, 2010
07/10
by
Bergeron, R. P.; Weldon, V. A
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The development of a reusable and space-based orbital transfer vehicle (OTV) necessitates an integral approach toward structural and propulsion subsystems design. A single engine installation necessitates moving the engine further aft and/or relocation of the engine gimbal point to accommodate vehicle control requirements. Penalties associated with gimbal point relocation without increasing stage length or modifying typical advanced engine concepts, as well as a method for minimizing such...
Topics: AEROASSIST, THERMAL PROTECTION, AERODYNAMIC CHARACTERISTICS, LIFT DRAG RATIO, ORBIT TRANSFER...
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1.1K
Jun 13, 2011
06/11
by
Butrica, Andrew J
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Th e decades-long debate over reusable launch vehicles (RLVs) versus expendable launch vehicles (ELVs) has been less a reasoned debate than a sustained argument for the building of reusable launchers instead of the standard throwaway rocket. The single greatest touted advantage of reusable launch vehicles is that they reduce launch costs.' Comparing reusable and expendable rockets is not simple; it is a rather complicated task not unlike the proverbial comparing of apples and oranges. To...
Topics: AERODYNAMIC HEATING, DATA BASES, MARS RECONNAISSANCE ORBITER, FREE MOLECULAR FLOW, MONTE CARLO...
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275
Jul 12, 2010
07/10
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Cooper, L. P.; Vinopal, T. J.; Florence, D. E.; Michel, R. W.; Brown, J. R.; Bergeron, R. P.; Weldon, V. A
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VEHICLE/ENGINE Integration Issues are explored for orbit transfer vehicles (OTV's). The impact of space basing and aeroassist on VEHICLE/ENGINE integration is discussed. The AOTV structure and thermal protection subsystem weights were scaled as the vehicle length and surface was changed. It is concluded that for increased allowable payload lengths in a ground-based system, lower length-to-diameter (L/D) is as important as higher mixture ration (MR) in the range of mid L/D ATOV's. Scenario...
Topics: AEROASSIST, PROPULSION SYSTEM PERFORMANCE, GEOSYNCHRONOUS ORBITS, LIFT DRAG RATIO, ORBIT TRANSFER...
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218
Jul 23, 2010
07/10
by
Cowie, L. L.; Henriksen, M.; Mushotzky, R
texts
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The constraints that the available X-ray spectral and imaging data place on the mass distribution and mass to light ratio of rich clusters are considered. It was found for the best determined cases that the mass to light ratio is less than 125 h sub 50 at radii exceeding 1 h sub 50 Mpc. The mass to light ratio is approximately constant at radii exceeding 1 h sub 50 Mpc but may rise to values of roughly 200 h sub 50 in the central regions. The fraction of the total mass that is in baryons,...
Topics: COST ANALYSIS, SPACECRAFT CONFIGURATIONS, SPACECRAFT PROPULSION, COST ESTIMATES, LONG DURATION...
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84
Aug 2, 2010
08/10
by
Fox, G. E
texts
eye 84
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In order to understand the structure of real structure spaces, we are studying the 5S rRNA structure space experimentally. A plasmid containing a synthetic 5S rRNA gene, two rRNA promoters, and transcription terminators has been assembled. Assays are conducted to determine if the foreign 5S rRNA is expressed, and to see whether or not it is incorporated into ribosomes. Evolutionary competition is used to determine the relative fitness of strains containing the foreign 5S rRNA and a control 5S...
Topics: AEROBRAKING, ORGANIC MATERIALS, CARBON DIOXIDE, HALF LIFE, HYDRODYNAMICS, INVENTORIES, OCEANS,...
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May 21, 2011
05/11
by
Fries, Sylvia Dought
texts
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Throughout our history the federal government has actively supported the exploration of our national frontiers. It has also administered and funded programs to develop the transportation and energy networks essential to the nation's economic growth and security. A federal role in national exploration and development is implicitly warranted in the US Constitution, which empowers the federal government to make and execute those laws necessary to 'promote the general Welfare' (Preamble). In...
Topics: AEROBRAKING, HYBRID PROPULSION, LOW EARTH ORBITS, PROPULSION SYSTEM PERFORMANCE, FIGURE OF MERIT,...
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489
May 22, 2011
05/11
by
Goering, J.; Bohlmann, R.; Wanthal, S.; Kautz, E.; Neri, Lawrence M
texts
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Experimental and analytical studies of the development of delaminations around fastener holes in composite structures are presented. This type of delamination is known to occur in composite skins that are mechanically fastened to a poorly mating substructure. Results of an experimental study to determine the resistance of laminates to the initiation of assembly induced delaminations and the residual strength of assembly damaged coupons are presented for AS4/3501-6, IM7/8551-7A, and AS4/PEEK...
Topics: AEROBRAKING, APPLICATIONS PROGRAMS (COMPUTERS), BOUNDARY CONDITIONS, FLUID PRESSURE, GRID...
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Jul 26, 2010
07/10
by
Goward, Samuel N.; Petzold, Donald E
texts
eye 326
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A comparison was conducted between ground reflectance spectra collected in Schefferville, Canada and imaging spectrometer observations acquired by the AVIRIS sensor in a flight of the ER-2 Aircraft over the same region. The high spectral contrasts present in the Canadian Subarctic appeared to provide an effective test of the operational readiness of the AVIRIS sensor. Previous studies show that in this location various land cover materials possess a wide variety of visible/near infrared...
Topics: AEROASSIST, EARTH ORBITS, FLIGHT TIME, LOW EARTH ORBITS, PARKING ORBITS, SPACECRAFT TRAJECTORIES,...
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189
May 29, 2011
05/11
by
Grosch, C. E
texts
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The dynamics of an ensemble of linear disturbances with a known probability distribution associated with the initial mode amplitudes are studied in boundary-layer flows through an analysis of the transport equations for the mean disturbance kinetic energy and disturbance energy dissipation rate. Effects of adverse and favorable pressure-gradients on the disturbance dynamics are also included in the analysis. Unlike the fully turbulent regime where nonlinear phase scrambling of the fluctuations...
Topics: MONTE CARLO METHOD, COMPUTATIONAL FLUID DYNAMICS, COMPUTERIZED SIMULATION, CONTINUUMS, HYPERSONIC...
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134
May 31, 2011
05/11
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Hair, Jonathan W.; Browell, Edward V.; Butler, Carolyn F.; Grant, William B.; DeYoung, Russell J.; Fenn, Marta A.; Brackett, Vince G.; Clayton, Marian B.; Brasseur, Lorrain
texts
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Ozone (O3) and aerosol scattering ratio profiles were obtained from airborne lidar measurements on thirty-eight aircraft flights over seven aircraft deployments covering the latitudes of 40 deg.-85 deg.N between 4 February and 23 May 2000 as part of the TOPSE (Tropospheric Ozone Production about the Spring Equinox) field experiment. The remote and in situ O3 measurements were used together to produce a vertically-continuous O3 profile from near the surface to above the tropopause. Ozone,...
Topics: AEROBRAKING, MARS ATMOSPHERE, 2001 MARS ODYSSEY, NUMERICAL ANALYSIS, MATHEMATICAL MODELS, HEAT...
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234
Jul 12, 2010
07/10
by
Hastings, L
texts
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Design, performance, and technology issues associated with reduced gravity propellant management for orbital transfer vehicles (OTV's) are reviewed. The in-space cryogenic management state-of-technology significantly affects the overall confidence level associated with a resupply mission and propulsion performance. Cryogen resupply sequences, timelines, controls, and associated crew involvement are all affected by the technology state. Additionally, OTV propellant tankage configurations,...
Topics: AEROASSIST, GUIDANCE (MOTION), THERMAL PROTECTION, LIFT DRAG RATIO, ORBIT TRANSFER VEHICLES,...
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Jul 12, 2010
07/10
by
Kittel, P
texts
eye 173
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Advances in storage technology and how passive techniques could be applied to the storage of propellants at the space station are described. The devices considered are passive orbital disconnect struts, cooled shield optimization, liftweight shields and catalytic converters.
Topics: AEROASSIST, SCAVENGING, ORBIT TRANSFER VEHICLES, PROPULSION SYSTEM PERFORMANCE, SPACE STATIONS,...
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221
Jul 12, 2010
07/10
by
Kroll, K
texts
eye 221
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Spacebasing of orbital transfer vehicles at a space station requires a depot that safely and efficiently stores and transfers the resupply propellants. In order to transfer propellants, a method effectively acquire only liquid and vent only gas must exist. A method that produces a low gravity to settle propellants would bypass these weaknesses, while allowing ground-like operations. This low gravity can be passively produced using gravity gradient techniques. A satellite with a large length to...
Topics: AEROASSIST, AERODYNAMIC CHARACTERISTICS, COMPUTER PROGRAMS, ORBIT TRANSFER VEHICLES, AEROBRAKING,...
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319
Jul 26, 2010
07/10
by
Kumar, Shiv S
texts
eye 319
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No Abstract Available
Topics: AEROBRAKING, RESOURCE ALLOCATION, TECHNOLOGY UTILIZATION, FINANCIAL MANAGEMENT, INTERPLANETARY...
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515
Jul 23, 2010
07/10
by
Lichten, S. M.; Border, J. S
texts
eye 515
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High precision orbit determination of Global Positioning System (GPS) satellites is a key requirement for GPS-based precise geodetic measurements and precise low-earth orbiter tracking, currently under study at JPL. Different strategies for orbit determination have been explored at JPL with data from a 1985 GPS field experiment. The most successful strategy uses multi-day arcs for orbit determination and includes fine tuning of spacecraft solar pressure coefficients and station zenith...
Topics: AEROASSIST, AEROBRAKING, MANNED MARS MISSIONS, ORBIT TRANSFER VEHICLES, AEROCAPTURE, ATMOSPHERIC...
843
843
Sep 20, 2010
09/10
by
Mateer, G. G.; Seegmiller, H. L.; Hand, L. A.; Szodruch, J
texts
eye 843
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Detailed experimental data were obtained on a supercritical airfoil and in the surrounding flowfield. Surface pressures were measured on both the model and wind-tunnel walls. The velocity field above the airfoil and the field in its wake was documented using a laser Doppler velocimeter. The data illustrate the effect of Mach number and angle of attack on the flow over the airfoil. Angles of attack ranged from 0.5 to 1.5 degrees and the Mach number was varied from 0.73 to 0.8. These variations...
Topics: INTERPLANETARY SPACECRAFT, MANNED SPACECRAFT, MISSION PLANNING, SPACE TRANSPORTATION, TECHNOLOGY...
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252
May 23, 2011
05/11
by
McCurry, J. B
texts
eye 252
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The purpose of the TA-2 contract was to provide advanced launch vehicle concept definition and analysis to assist NASA in the identification of future launch vehicle requirements. Contracted analysis activities included vehicle sizing and performance analysis, subsystem concept definition, propulsion subsystem definition (foreign and domestic), ground operations and facilities analysis, and life cycle cost estimation. The basic period of performance of the TA-2 contract was from May 1992...
Topics: BLUNT BODIES, SCHLIEREN PHOTOGRAPHY, CYLINDRICAL BODIES, AERODYNAMIC FORCES, FLOW VISUALIZATION,...
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218
Aug 2, 2010
08/10
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Miller, Mark D.; Barr, Stanley J.; Gryphon, Coranth D.; Keegan, Jeff; Kniker, Catherine A.; Krolak, Patrick D
texts
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The Management and Security Expert (MASE) is a distributed expert system that monitors the operating systems and applications of a network. It is capable of gleaning the information provided by the different operating systems in order to optimize hardware and software performance; recognize potential hardware and/or software failure, and either repair the problem before it becomes an emergency, or notify the systems manager of the problem; and monitor applications and known security holes for...
Topics: AEROBRAKING, COMPUTERIZED SIMULATION, DEGREES OF FREEDOM, DYNAMIC PRESSURE, MARS ATMOSPHERE, MARS...
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232
Sep 20, 2010
09/10
by
Mog, Robert A.; Helba, Michael J.; Hill, Janeil B
texts
eye 232
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The purpose of this research is to provide Space Station Freedom protective structures design insight through the coupling of design/material requirements, hypervelocity impact phenomenology, meteoroid and space debris environment sensitivities, optimization techniques and operations research strategies, and mission scenarios. The goals of the research are: (1) to develop a Monte Carlo simulation tool which will provide top level insight for Space Station protective structures designers; (2) to...
Topics: INTERPLANETARY SPACECRAFT, LIFE SUPPORT SYSTEMS, SPACECRAFT CONFIGURATIONS, SPACECRAFT POWER...
29,310
29K
Oct 18, 2011
10/11
by
NASA eClips
movies
eye 29,310
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People from across the country worked together to make sure NASA's Space Shuttles could complete their missions. Learn how this unique workhorse is responsible for amazing advances in astrophysics and planetary science, just because it flew.
Topic: NASA, NIA, eClips, Launchpad, high school, video, education, mathematics, technology, science,...
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334
Mar 5, 2009
03/09
by
NASA LaRC Office of Education
movies
eye 334
favorite 1
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NASA Destination Tomorrow video containing four segments as described below. First segment of episode 20 that contains the Behind the Scenes segment in which Scott Striepe discusses how the Mars Reconnaissance Orbiter (MRO) will pave the way for future missions to Mars. The first segment of episode 20 discusses the technology behind the MRO and how aerobraking will be used to decrease the amount of fuel necessary for the mission. The Mars Reconnaissance Orbiter segment ends with a Did You Know?...
Topics: NASA Destination Tomorrow, Kera O'Bryon, Behind The Scenes, Jennifer Pulley, Mars Reconnaissance...
Source: http://nasa.ibiblio.org/details.php?videoid=6533&start=20&subject=Science
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203
Mar 5, 2009
03/09
by
NASA LaRC Office of Education
movies
eye 203
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NASA Destination Tomorrow Segment exploring the function of aerobraking and how this helps reduce costs and create more room in aircraft.
Topics: NASA Destination Tomorrow, Aerobraking, Spacecraft, Air Travel, Space Shuttle, Gravitational Field,...
Source: http://nasa.ibiblio.org/details.php?videoid=6396&start=0&subject=Science-Missions
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197
Mar 5, 2009
03/09
by
NASA LaRC Office of Education
movies
eye 197
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First segment of episode 20 that contains the Behind the Scenes segment in which Scott Striepe discusses how the Mars Reconnaissance Orbiter (MRO) will pave the way for future missions to Mars. The first segment of episode 20 discusses the technology behind the MRO and how aerobraking will be used to decrease the amount of fuel necessary for the mission. The Mars Reconnaissance Orbiter segment ends with a Did You Know? segment describing the concern NASA scientists have with Martian dust.
Topics: NASA Destination Tomorrow, Kera O'Bryon, Behind The Scenes, Jennifer Pulley, Mars Reconnaissance...
Source: http://nasa.ibiblio.org/details.php?videoid=6534&start=20&subject=Science
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1.1K
Mar 5, 2009
03/09
by
NASA LaRC Office of Education
movies
eye 1,092
favorite 0
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NASA Destination Tomorrow Video containing three segments as described below. NASA Destination Tomorrow Segment exploring the function of aerobraking and how this helps reduce costs and create more room in aircraft. NASA Destination Tomorrow Segment exploring new materials technology development and how it has revolutionized the world of science and technology. NASA Destination Tomorrow Segment exploring a newly discovered moon called Titan that revolves around the planet Saturn.
Topics: NASA Destination Tomorrow, Aerobraking, Spacecraft, Air Travel, Space Shuttle, Gravitational Field,...
Source: http://nasa.ibiblio.org/details.php?videoid=6395&start=0&subject=Science-Missions
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79
Mar 5, 2009
03/09
by
NASA LaRC Office of Education
movies
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NASA Connect Segment explaining how NASA scientists survey Mars with the Mars Global Surveyor. The video also explains aerobraking and how geometry influences this.
Topics: NASA Connect, Geometry, Mars Global Surveyor, Aerobraking, Ellipse, Orbit
Source: http://nasa.ibiblio.org/details.php?videoid=6032&start=0&subject=Mathematics
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337
Mar 5, 2009
03/09
by
NASA LaRC Office of Education
movies
eye 337
favorite 0
comment 0
NASA Connect Video containing six segments as described below. NASA Connect Segment involving students in a classroom activity that measures shadows and uses geometry to determine sizes of angles. NASA Connect Segment explaining questions about Erastothenes, the Earth's circumference, parallel lines, angle relationships, and a transversal. NASA Connect Segment featuring an online activity to show students how to design a planetary observer like the Mars Global Surveyor. NASA Connect Segment...
Topics: NASA Connect, Measurement, Shadows, Angles, Gnomon, Student Activity, Height, Length, Calculator,...
Source: http://nasa.ibiblio.org/details.php?videoid=6026&start=0&subject=Mathematics
Aerobraking has become a proven approach for orbital missions at Mars. A launch of a 1000 kg class spacecraft on a Delta class booster saves 90% of the post-MOI fuel otherwise required to circularize the orbit. In 1997, Mars Global Surveyor demonstrated the feasibility and Mars 2001 Odyssey completed a nearly trouble free aerobraking phase in January 2002. In 2006, Mars Reconnaissance Orbiter will also utilize aerobraking. From the flight operations standpoint, however, aerobraking is labor...
Topics: NASA Technical Reports Server (NTRS), AEROBRAKING, MARS MISSIONS, SPACECRAFT MANEUVERS,...
Aerobraking has proven to be an effective means of increasing the science payload for planetary orbiting missions and/or for enabling the use of less expensive launch vehicles. Though aerobraking has numerous benefits, large operations cost have been required to maintain the aerobraking time line without violating aerodynamic heating or other constraints. Two operations functions have been performed on an orbit by orbit basis to estimate atmospheric properties relevant to aerobraking. The...
Topics: NASA Technical Reports Server (NTRS), AEROBRAKING, AUTONOMY, SPACE MISSIONS, ATMOSPHERIC MODELS,...
Topics covered include: Charge-Control Unit for Testing Lithium-Ion Cells; Measuring Positions of Objects Using Two or More Cameras; Lidar System for Airborne Measurement of Clouds and Aerosols; Radiation-Insensitive Inverse Majority Gates; Reduced-Order Kalman Filtering for Processing Relative Measurements; Spaceborne Processor Array; Instrumentation System Diagnoses a Thermocouple; Chromatic Modulator for a High-Resolution CCD or APS; Commercial Product Activation Using RFID; Cup Cylindrical...
Topics: NASA Technical Reports Server (NTRS), AEROBRAKING, CHARGE COUPLED DEVICES, DECISION SUPPORT...
Since 2004, CNES has decided to apply the end of life Code of Conduct rules to debris mitigation. Originally drawn up by the main European space agencies, it contains basic rules to be applied in space in order to limit the increase of orbital debris. In low Earth orbit, the rule is to limit in-orbit lifetime to 25 years after the end of the operational mission, or else to transfer to a graveyard orbit above 2000 km. In order to follow these instructions, a task force was set up in 2005 to find...
Topics: NASA Technical Reports Server (NTRS), CIRCULAR ORBITS, AEROBRAKING, INFLATABLE STRUCTURES, LOW...
The Radiative Heating Experiment, RHE, aboard the Aeroassist Flight Experiment, AFE, (now cancelled) was to make in-situ measurements of the stagnation region shock layer radiation during an aerobraking maneuver from geosynchronous to low earth orbit. The measurements were to provide a data base to help develop and validate aerothermodynamic computational models. Although cancelled, much work was done to develop the science requirements and to successfully meet RHE technical challenges. This...
Topics: NASA Technical Reports Server (NTRS), AEROASSIST, AERODYNAMIC HEATING, AEROTHERMODYNAMICS,...
The peak deceleration load allowed for aerobraking of manned vehicles is a critical parameter in planning future excursions to Mars. However, considerable variation exists in the limits used by various investigators. The goal of this study was to determine the most appropriate level for this limit. Methods: Since previous U.S. space flights have been limited to 84 days duration, Soviet flight results were examined. Published details of Soviet entry trajectories were not available. However,...
Topics: NASA Technical Reports Server (NTRS), AEROBRAKING, AEROCAPTURE, AEROSPACE MEDICINE, DECELERATION,...
An advanced OTV is one of a number of advanced STS vehicles that the NASA OAST Space Systems Division Transportation Systems Office identified as candidates for future vehicle development. Vehicle requirements as well as technology needs and need dates were established and technology programs initiated to support those potential developments in a timely manner. It is assumed that advanced OTV will be space based and fully reusable for low cost operations, use aeroassist for return to...
Topics: NASA Technical Reports Server (NTRS), AEROASSIST, ORBIT TRANSFER VEHICLES, PROPULSION SYSTEM...
Lunar and Mars return conditions are examined using the LAURA flow field code and the LORAN radiation code to assess the effect of radiative coupling on axisymmetric thermochemical nonequilibrium flows. Coupling of the two codes is achieved iteratively. Special treatment required to couple radiation in a shock-capturing method is discussed. Results indicate that while coupling effects are generally the same as occur in equilibrium flows, under certain conditions radiation can modify the...
Topics: NASA Technical Reports Server (NTRS), FLOW DISTRIBUTION, NONEQUILIBRIUM FLOW, RADIATION EFFECTS,...
The current technical effort is part of the third phase of a broad-scoped and systematic study of space transfer concepts for human lunar and Mars missions. The study addressed the technical issues relating to the First Lunar Outpost (FLO) habitation vehicle with emphasis in the structure, power, life support system, and radiation environment.
Topics: NASA Technical Reports Server (NTRS), INTERPLANETARY SPACECRAFT, LUNAR BASES, LUNAR EXPLORATION,...
MOLA gridded data based on profiles collected during the Aerobraking Hiatus and Science Phasing Operations suggest the crustal dichotomy boundary west of Tempe continues beneath Alba volcanics, at least to 105 W at about 50 N. A broad shelf-like region in the Alba units is continuous with a similar region of Tempe in which Hesperian volcanics overlie Noachian cratered terrain. Perspective views show significant changes in the sloping character of the flanks of Alba east and west of 105W, with...
Topics: NASA Technical Reports Server (NTRS), DICHOTOMIES, CRUSTS, BOUNDARIES, TOPOGRAPHY, DATA BASES,...
Annual simulations of Mars' atmosphere made with the NASA Ames Mars General Circulation Model have been used to extract and generate products to provide statistical products that detail the variability of Mars' atmosphere on fairly short time scales. These products are needed for the creation of a new version of Mars-GRAM, due for completion in June, 1999. The updated Mars-Gram, in turn, will provide guidance for forthcoming aerobraking and aerocapture activities. We have created files...
Topics: NASA Technical Reports Server (NTRS), MARS MISSIONS, DIURNAL VARIATIONS, ATMOSPHERIC GENERAL...
The use of atmospheric drag for slowing satellite in high energy, high apogee orbits to a lower energy, lower apogee orbit about the Earth is investigated. The high energy orbit is assumed to intercept the Earth's atmosphere. Guidance for the atmospheric phase of the trajectory may be done using the aerodynamic forces generated by the passage through the atmosphere. This research was concerned with the investigation of several methods of guidance during the atmospheric phase to cause a...
Topics: NASA Technical Reports Server (NTRS), AEROASSIST, ATMOSPHERIC EFFECTS, BOUNDARY VALUE PROBLEMS,...
A preliminary design is presented for a low-thrust Laser Powered Interorbital Vehicle (LPIV) intended for cargo transportation between an earth space station and a lunar base. The LPIV receives its power from two iodide laser stations, one orbiting the earth and the other located on the surface of the moon. The selected mission utilizes a spiral trajectory, characteristic of a low-thrust spacecraft, requiring 8 days for a lunar rendezvous and an additional 9 days for return. The ship's...
Topics: NASA Technical Reports Server (NTRS), ENGINE DESIGN, LASER PROPULSION, PLASMA ENGINES, PLASMA...
The basic components of the design for the orbital transfer vehicle (OTV) are outlined. The Project Orion and the MOVERS OTV design are compared. The nature of the work and the specifics will be reviewed. The propellant systems are summarized along with the dollar savings. The strengths and weaknesses are highlighted for each OTV.
Topics: NASA Technical Reports Server (NTRS), DESIGN ANALYSIS, ORBIT TRANSFER VEHICLES, SPACECRAFT DESIGN,...
This paper describes a space infrastructure concept that exploits lunar water for propellant production and delivers it to users in cis-lunar space. The goal is to provide responsive economical space transportation to destinations beyond low Earth orbit (LEO) and enable in-space commerce. This is a game changing concept that could fundamentally affect future space operations, provide greater access to space beyond LEO, and broaden participation in space exploration. The challenge is to minimize...
Topics: NASA Technical Reports Server (NTRS), CISLUNAR SPACE, COMMERCE, PROPELLANTS, EXTRATERRESTRIAL...
Rarefied flows about hypersonic vehicles entering the upper atmosphere or through nozzles expanding into a near vacuum may only be simulated accurately with a direct simulation Monte Carlo (DSMC) method. Under this grant, researchers enhanced the models employed in the DSMC method and performed simulations in support of existing NASA projects or missions. DSMC models were developed and validated for simulating rotational, vibrational, and chemical relaxation in high-temperature flows, including...
Topics: NASA Technical Reports Server (NTRS), COMPUTATIONAL FLUID DYNAMICS, COMPUTERIZED SIMULATION, HIGH...
A reuseable orbit transfer vehicle concept was defined and subsequent recommendations for the design criteria of an advanced LO2/LH2 engine were presented. The major characteristics of the vehicle preliminary design include a low lift to drag aerocapture capability, main propulsion system failure criteria of fail operational/fail safe, and either two main engines with an attitude control system for backup or three main engines to meet the failure criteria. A maintenance and servicing approach...
Topics: NASA Technical Reports Server (NTRS), AEROBRAKING, AEROCAPTURE, ORBIT TRANSFER VEHICLES, PROPULSION...
Research on aerobraking guidance schemes is presented. The intent is to produce aerobraking guidance trajectories exhibiting many of the desirable characteristics of optimal aerobraking trajectories. Both one-control schemes and two-control schemes are studied. The research is in the interest of aeroassisted flight experiment vehicles (AFE) and aeroassisted orbital transfer (AOT) vehicles.
Topics: NASA Technical Reports Server (NTRS), AEROASSIST, AEROBRAKING, EARTH ORBITS, ORBIT TRANSFER...
A summary is given of several studies into problems associated with aerobraking a manned vehicle into a Martian capture orbit. The problems investigated are the establishment of entry flight path angle windows that allow aerocapture; the determination of the sensitivity of the entry trajectory to initial flight path angle; the determination of the effect on aerocapture of the assumed Martian atmosphere model; and the determination of the effect of random atmosphere disturbances on adaptive...
Topics: NASA Technical Reports Server (NTRS), AEROBRAKING, AEROCAPTURE, FLIGHT PATHS, MANNED SPACECRAFT,...
The topics covered include the following: (1) space basing agenda; (2) mission scenario 4E-5B, crew and Lunar Excursion Vehicle (LEV) delivery; (3) final concept candidate, crew concept 4E-2B; (4) space transfer vehicle (STV) concept 4E-5B; (5) configuration summary for crew concept 4E-5B; (6) configuration definition for crew concept 4E-5B; (7) low earth orbit node assembly and checkout operations; (8) criteria for operation objectives; (9) LTV and STV main engines; (10) Space Station Freedom...
Topics: NASA Technical Reports Server (NTRS), INTERPLANETARY SPACECRAFT, LUNAR SPACECRAFT, MANNED...
A comprehensive treatment of comet/asteroid interaction with the atmosphere, ensuring surface impact, and resulting organic pyrolysis is required to determine whether more than a negligible fraction of the organics in incident comets and asteroids actually survived collision with Earth. Results of such an investigation, using a smoothed particle hydrodynamic simulation of cometary and asteroidal impacts into both oceans and rock, demonstrate that organics will not survive impacts at velocities...
Topics: NASA Technical Reports Server (NTRS), AEROBRAKING, ASTEROIDS, ATMOSPHERIC CHEMISTRY, BIOLOGICAL...
