An overall systems evaluation was made of five candidate navigation systems in support of earth orbit missions. The five systems were horizon sensor system, unkown landmark tracking system, ground transponder system, manned space flight network, and tracking and data relay satellite system. Two reference missions were chosen: a low earth orbit mission and a transfer trajectory mission from low earth orbit to geosynchronous orbit. The specific areas addressed in the evaluation were performance,...
Topics: NASA Technical Reports Server (NTRS), EARTH ORBITS, SPACE NAVIGATION, LOW EARTH ORBITS, SYSTEMS...
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222
Jul 26, 2010
07/10
by
Palmer, Michael T
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An effort which investigated concepts for displaying dynamic system status and fault history (propagation) information to the flight crew is described. This investigation was performed by developing several candidate display formats and then conducting comprehension tests to determine those characteristics that made one format preferable to another for presenting this type of information. Twelve subjects participated. Flash tests, or limited time exposure tests, were used to determine the...
Topics: EARTH ORBITS, EXPERIMENT DESIGN, SPACE FLIGHT, SPACEBORNE EXPERIMENTS, SPACECRAFT DESIGN, AEROSPACE...
439
439
May 22, 2011
05/11
by
Hayder, M. E.; Turkel, E
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eye 439
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Ongoing activities are focused on capturing the sound source in a supersonic jet through careful large eddy simulation (LES). One issue that is addressed is the effect of the boundary conditions, both inflow and outflow, on the predicted flow fluctuations, which represent the sound source. In this study, we examine the accuracy of several boundary conditions to determine their suitability for computations of time-dependent flows. Various boundary conditions are used to compute the flow field of...
Topics: CARBON, LIFE (DURABILITY), PYROLYTIC GRAPHITE, EROSION, EXPOSURE, LOW EARTH ORBITS, OXYGEN ATOMS,...
927
927
Jul 11, 2010
07/10
by
NON
texts
eye 927
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Vibroacoustic measuring and analytical methods are reported for evaluating operational aspects of mechanical and structural systems.
Topics: BIOLOGICAL EFFECTS, EARTH ORBITS, WEIGHTLESSNESS, ANIMALS, COSMOS SATELLITES, FUNGI
A ten cell bipolar nickel hydrogen 6.5 ampere-hour battery demonstrated over 2000 low Earth orbit cycles at an 80 percent depth-of-discharge. Charge/discharge cyclic ampere-hour and watt-hour efficiencies of 88 and 76 percent, respectively, observed. Peak power capability was determined at 1.1 kW. A 10C discharge rate yields 83 percent of the nominal stark capacity to the 1.0 volt cut off in just under 6 minutes.
Topics: NASA Technical Reports Server (NTRS), BIPOLARITY, EARTH ORBITS, NICKEL HYDROGEN BATTERIES,...
137
137
Sep 20, 2010
09/10
by
Moser, Robert D.; Rogers, Michael M
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eye 137
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A direct numerical simulation of a plane turbulent mixing layer has been performed. The simulation was initialized using two turbulent velocity fields obtained from direct numerical simulation of a turbulent boundary layer at momentum thickness Reynolds number 300 (Spalart, 1988). The mixing layer is allowed to evolve long enough for self-similar linear growth to occur, with the visual thickness Reynolds number reaching 14,000. The simulated flow is examined for evidence of the coherent...
Topics: EARTH ORBITS, LOW EARTH ORBITS, MARKETING, UNITED KINGDOM, LAUNCH VEHICLES, LAUNCHING, RESEARCH AND...
319
319
May 31, 2011
05/11
by
Goodrich, R. G.; Pullam, B.; Rickle, D.; Litchford, R. J.; Robertson, G. A.; Schmidt, D. D
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eye 319
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Basic research on advanced plasma-based propulsion systems is routinely focused on plasmadynamics, performance, and efficiency aspects while relegating the development of critical enabling technologies, such as flight-weight magnets, to follow-on development work. Unfortunately, the low technology readiness levels (TRLs) associated with critical enabling technologies tend to be perceived as an indicator of high technical risk, and this, in turn, hampers the acceptance of advanced system...
Topics: LOW EARTH ORBITS, PROPELLANT STORAGE, GEOSYNCHRONOUS ORBITS, EXTRATERRESTRIAL RESOURCES
A preliminary design effort directed toward a low concentration ratio photovoltaic array system capable of delivering multihundred kilowatts (300 kW to 1000 kW range) in low earth orbit is described. The array system consists of two or more array modules each capable of delivering between 113 kW to 175 kW using silicon solar cells or gallium arsenide solar cells, respectively. The array module deployed area is 1320 square meters and consists of 4356 pyramidal concentrator elements. The module,...
Topics: NASA Technical Reports Server (NTRS), CONCENTRATORS, EARTH ORBITS, LOW EARTH ORBITS, SOLAR ARRAYS,...
244
244
May 21, 2011
05/11
by
Ward, John L.; Mcintire, Gerr
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eye 244
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The NASA Satellite Instrumentation Calibrator (NASIC) is a visible and near-infrared spectrometer used to calibrate various satellite instruments by underflying those instruments in a NASA ER-2 aircraft. The calibration instrument's hardware and software are documented. The design, operation, and function of an Ebert-Fastie monochronomator, which by means of a moveable diffraction grating, becomes a visible and near-infrared spectrometer used to calibrate satellite-borne instruments by high...
Topics: EARTH ORBITS, SILICON, SOLAR CELLS, RADIANT FLUX DENSITY, RADIATION DAMAGE, SOLAR ARRAYS, CHARGED...
Low Earth orbit cycle, synchronous orbit cycle, general performance, and vibration test results, and gas analyses are reported.
Topics: NASA Technical Reports Server (NTRS), EARTH ORBITS, NICKEL CADMIUM BATTERIES, SPACECRAFT POWER...
The National Aeronautics and Space Administration's (NASA's) Space Launch System (SLS) will contribute a new national capability for human space flight and scientific missions to low- Earth orbit (LEO) and beyond. Exploration beyond Earth orbit will be an enduring legacy to future generations, confirming America s desire to explore, learn, and progress. The SLS Program, managed at NASA s Marshall Space Fight Center, will develop the heavy lift vehicle that will launch the Orion Multi-Purpose...
Topics: NASA Technical Reports Server (NTRS), SPACECRAFT LAUNCHING, SPACE EXPLORATION, CREW EXPLORATION...
In 1986, Eagle-Picher Industries was selected by the Air Force to develop sodium sulfur cells for satellite applications. Specifically, the development program was geared toward low earth orbit goals requiring high charge and/or discharge rates. A number of improvements have been made on the cell level and a transition to a complete space battery was initiated at Eagle-Picher. The results of six months of testing a 250 watt/hour sodium sulfur space battery look very promising. With over 1000...
Topics: NASA Technical Reports Server (NTRS), CHARGE EFFICIENCY, DISCHARGE, FLUX DENSITY, SODIUM SULFUR...
The program LIBRATE calculates velocities for trajectories from low earth orbit (LEO) to four of the five libration points (L2, L3, L4, and L5), and from low lunar orbit (LLO) to libration points L1 and L2. The flight to be analyzed departs from a circular orbit of any altitude and inclination about the Earth or Moon and finishes in a circular orbit about the Earth at the desired libration point within a specified flight time. This program produces a matrix of the delta V's needed to complete...
Topics: NASA Technical Reports Server (NTRS), COMPUTER PROGRAMS, LIBRATION, ORBITAL MECHANICS, SPACECRAFT...
374
374
Jul 23, 2010
07/10
by
Simons, Rainee N.; Bhasin, Kul. B
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eye 374
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Direct current and also the microwave characteristics of optically illuminated AlGaAs/GaAs HEMT are experimentally measured for the first time and compared with that of GaAs MESFET. The results showed that the average increase in the gain is 2.89 dB under 1.7 nW/sq cm optical intensity at 0.83 microns. Further, the effect of illumination on S-parameters is more pronounced when the devices are biased close to pinch off. Novel applications of optically illuminated HEMT as a variable gain...
Topics: CHEMICAL PROPULSION, ORBIT CALCULATION, EXHAUST VELOCITY, ION PROPULSION, MANNED SPACE FLIGHT,...
Since 1964 at least 56 spacecraft and two launch vehicle upper stages have been deliberately fragmented while in Earth orbit. Many of these events have had no long-lasting effects on the near-Earth space environment, but one represents the most devastating satellite breakup in history that will pose hazards to operational spacecraft in low Earth orbit for decades to come. International space debris mitigation guidelines now call for avoiding the creation of long-lived debris from intentional...
Topics: NASA Technical Reports Server (NTRS), AEROSPACE ENVIRONMENTS, FRAGMENTATION, LAUNCH VEHICLES, EARTH...
562
562
May 22, 2011
05/11
by
Neely, W. C.; Bozak, M. J.; Williams, J. R
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eye 562
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X-ray photoelectron spectroscopy (XPS), Rutherford Back Scattering (RBS) studies of each of sample received were completed. Since low angle X-ray could not be performed because of instrumentation problems, Auger spectrometry was employed instead. The results of these measurements for each of the samples is discussed in turn.
Topics: CONTAMINATION, FLUENCE, GROUND TESTS, IRRADIANCE, NONLINEARITY, OXIDATION, EARTH ORBITS, EROSION,...
The program LP1 calculates outbound and return trajectories between low earth orbit (LEO) and libration point no. 1 (L1). Libration points (LP) are defined as locations in space that orbit the Earth such that they are always stationary with respect to the Earth-Moon line. L1 is located behind the Moon such that the pull of the Earth and Moon together just cancel the centrifugal acceleration associated with the libration point's orbit. The input required from the user to define the flight is...
Topics: NASA Technical Reports Server (NTRS), COMPUTER PROGRAMS, LIBRATION, ORBITAL MECHANICS,...
Aerospace engineering students at the Virginia Polytechnic Institute and State University undertook three design projects under the sponsorship of the NASA/USRA Advanced Space Design Program. All three projects addressed cargo and/or crew transportation between low Earth orbit and geosynchronous Earth orbit. Project SPARC presents a preliminary design of a fully reusable, chemically powered aeroassisted vehicle for a transfer of a crew of five and a 6000 to 20000 pound payload. The ASTV project...
Topics: NASA Technical Reports Server (NTRS), AEROASSIST, AEROSPACE ENGINEERING, CARGO, EARTH ORBITS, ORBIT...
148
148
May 31, 2011
05/11
by
NON
texts
eye 148
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Kuljian Corporation provides design engineering and construction management services for power generating plants in more than 20 countries. They used WASP (Calculating Water and Steam Properties), a COSMIC program to optimize power station design. This enabled the company to substantially reduce lead time and software cost in a recent design project.
Topics: EARTH MAGNETOSPHERE, NASA PROGRAMS, PROGRESS, AUTONOMY, CONSTELLATIONS, DEEP SPACE, EARTH ORBITS
The Space Operations Center is a concept for a shuttle-service, permanent, manned facility in low Earth orbit. An analysis of this concept was conducted and the results are reported. It is noted that there are no NASA plans at present to implement such a concept. The results are intended for consideration in future planning.
Topics: NASA Technical Reports Server (NTRS), EARTH ORBITS, OPERATIONS RESEARCH, SPACE SHUTTLES, SPACE...
232
232
Aug 2, 2010
08/10
by
Masud, Abu S. M
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eye 232
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Fellowship activities were directed towards the identification of opportunities for application of the Multiple Criteria Decision Making (MCDM) techniques in the Space Exploration Initiative (SEI) domain. I identified several application possibilities and proposed demonstration application in these three areas: evaluation and ranking of SEI architectures, space mission planning and selection, and space system design. Here, only the first problem is discussed. The most meaningful result of the...
Topics: LAUNCH VEHICLES, SPACE STATION FREEDOM, LIFTING BODIES, LIFTING REENTRY VEHICLES, MANNED...
282
282
Sep 20, 2010
09/10
by
Langhoff, Stephen R.; Bauschlicher, Charles W., Jr.; Taylor, Peter R
texts
eye 282
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The bond dissociation energies (D sub e) of C2H2, C2H4, C2H6, N2, N2H2, and N2H4 are studied at various levels of correlation treatment. The convergence of D sub e with respect to the one particle basis is studied at the single reference modified coupled-pair functional (MCPF) level. At all levels of correlation treatment, the errors in the bond dissociation energies increase with the degree of multiple bond character. The multireference configuration interaction (MRCI) D sub e values,...
Topics: CLEANING, MODULES, PARKING ORBITS, POSITION (LOCATION), REFUELING, SPACE SHUTTLES, SPACECRAFT...
543
543
Jun 11, 2011
06/11
by
OBryan, Martha V.; Kniffin, Scott D., et al; Seidleck, Christina M.; Carts, Martin A.; LaBel, Kenneth A.; Marshall, Cheryl J.; Reed, Robert A.; Sanders, Anthony B.; Hawkins, Donald K.; Cox, Stephen R.
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We present data on the vulnerability of a variety of candidate spacecraft electronics to proton and heavy ion induced single event effects. Devices tested include digital, analog, linear bipolar, and hybrid devices, among others.
Topics: LOW EARTH ORBITS, LIBRATION, FORMATION FLYING, RETROGRADE ORBITS, PERTURBATION THEORY, LAUNCHING
Development of a high specific energy nickel electrode is the main goal of the lightweight nickel electrode program at NASA-Lewis. The approach was to improve the nickel electrode by continuing combined in-house and contract efforts to develop a more efficient and lighter weight electrode for the nickel-hydrogen cell. Lightweight plaques are used as conductive supports for the nickel hydroxide active material. These plaques are commercial products that are fabricated into nickel electrodes by...
Topics: NASA Technical Reports Server (NTRS), ELECTROCHEMISTRY, ELECTRODES, LIFE (DURABILITY), NICKEL...
The principal source of radiation for low-earth-orbit, low inclination space flights is in the area of the South Atlantic magnetic anomaly. None of the Gemini dose measurements reported in the paper are of high enough intensity to be considered hazardous. There is a trend toward larger doses as missions are flown higher and longer. Extended orbital operations between 1400 and 4400 kilometers would encounter high interior radiation levels. Pronounced spacecraft geometry effects have been...
Topics: NASA Technical Reports Server (NTRS), DOSIMETERS, EXTRATERRESTRIAL RADIATION, GEMINI PROJECT, EARTH...
An ongoing preliminary design effort directed toward a low-concentration-ratio photovoltaic array system based on 1984 technology and capable of delivering multi-hundred kilowatts (300 kW to 1000 kW range) in low earth orbit is described. The array system consists of two or more array modules each capable of delivering between 80 kW to 172 kW using silicon solar cells or gallium arsenide solar cells respectively. The array module deployed area is 1320 square meters and consists of 4356...
Topics: NASA Technical Reports Server (NTRS), EARTH ORBITS, LOW CONCENTRATIONS, LOW EARTH ORBITS, SOLAR...
Work accomplished in the analysis of systems, space basing concepts, and space shuttle studies and alternative concepts is reported with emphasis on the preparation of cost estimates. It is concluded that space basing, as an operational mode, permits the assembly and maintenance of large space vehicles and payloads in low earth orbit, and may become the basing mode for space exploration.
Topics: NASA Technical Reports Server (NTRS), COST ESTIMATES, SPACE BASES, SPACE SHUTTLES, SYSTEMS...
The ability to perform extravehicular activity (EVA), both human and robotic, has been identified as a key component to space missions to support such operations as assembly and maintenance of space system (e.g. construction and maintenance of the International Space Station), and unscheduled activities to repair an element of the transportation and habitation systems that can only be accessed externally and via unpressurized areas. In order to make human transportation beyond lower earth orbit...
Topics: NASA Technical Reports Server (NTRS), EXTRAVEHICULAR ACTIVITY, MODULARITY, SPACE MISSIONS, SYSTEMS...
The 3.5 inch, 50 ampere-hour nickel-hydrogen cell was on a Low Earth Orbit (LEO) test regime and was being cycled at 10 C and 60 percent depth of discharge. At cycle number 511 the Automatic Control and Data Acquisition System (ACDAS) terminated the test when the end of discharge voltage dropped below the 1.00 volt cutoff. Upon removal of the stack assembly from the pressure vessel, portions of the zircar separator were found to be completely missing. Upon further examination portions of both...
Topics: NASA Technical Reports Server (NTRS), FAILURE ANALYSIS, NICKEL HYDROGEN BATTERIES, RECOMBINATION...
331
331
Jul 12, 2010
07/10
by
Mcallister, J. G
texts
eye 331
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Space based servicing of an orbit transfer vehicle (OTV) was previously outlined in sufficient detail to arrive at OTV and support system servicing requirements. Needed space station facilities and their functional requirements were identified. The impact of logistics and space serviceable design on the OTV design is detailed herein. RL10 derivative rocket engine inspection task times are enumerated.
Topics: EARTH ORBITS, SPACE TRANSPORTATION SYSTEM, TECHNOLOGY ASSESSMENT, GEOSYNCHRONOUS ORBITS, ORBIT...
199
199
Sep 20, 2010
09/10
by
Steely, Sidney L
texts
eye 199
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The similarity of the functional forms of quantum mechanical harmonic oscillators and the modes of Hermite-Gaussian laser beams is illustrated. This functional similarity provides a direct correlation to investigate the spot size of large-order mode Hermite-Gaussian laser beams. The classical limits of a corresponding two-dimensional harmonic oscillator provide a definition of the spot size of Hermite-Gaussian laser beams. The classical limits of the harmonic oscillator provide integration...
Topics: COST ANALYSIS, GROUND STATIONS, LOW EARTH ORBITS, LASER POWER BEAMING, LIFE CYCLE COSTS, ORBIT...
The environmental and design constraints are reviewed along with some insight into the established design and quality assurance practices that apply to low earth orbit (LEO) space flight hardware. It is intended as an introduction for people unfamiliar with space flight considerations. Some basic data and a bibliography are included.
Topics: NASA Technical Reports Server (NTRS), EARTH ORBITS, EXPERIMENT DESIGN, SPACE FLIGHT, SPACEBORNE...
508
508
May 21, 2011
05/11
by
Henze, William, Jr
texts
eye 508
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A catalog of observations (experiments) obtained by the Ultraviolet Spectrometer and Polarimeter (UVSP) on the Solar Maximum Mission (SMM) from Feb. 1980 to Nov. 1989 is presented. The information for each entry includes the time of each observation, the observed position of the Sun, the spacecraft roll angle, the slit used, and instrument parameters such as raster size, pixel spacing, wavelength, polarimeter usage, gate time, etc. The document is split into three volumes: Volume 1 contains...
Topics: AEROSPACE VEHICLES, LOW EARTH ORBITS, MULTIDISCIPLINARY DESIGN OPTIMIZATION, DESIGN ANALYSIS,...
Mission specifications for three generic mission classes are generated to provide a baseline for definition and analysis of data acquisition platform system concepts. The mission specifications define compatible groupings of sensors that satisfy specific earth resources and environmental mission objectives. The driving force behind the definition of sensor groupings is mission need; platform and space transportation system constraints are of secondary importance. The three generic mission...
Topics: NASA Technical Reports Server (NTRS), EARTH RESOURCES, ENVIRONMENT EFFECTS, MISSION PLANNING,...
Lunar vehicles that will be space based and reusable will require resupply of propellants in orbit. Approximately 75 pct. of the total mass delivered to low earth orbit will be propellants. Consequently, the propellant management techniques selected for Space Exploration Initiative (SEI) orbital operations will have a major influence on the overall SEI architecture. Five proposed propellant management facility (PMF) concepts were analyzed and compared in order to determine the best method of...
Topics: NASA Technical Reports Server (NTRS), EXTERNAL TANKS, PROPELLANT TRANSFER, REFUELING, SPACE STATION...
Economical unmanned earth orbit transportation for large payloads is evaluated. The high exhaust velocity achievable with electric propulsion is attractive because it minimizes the propellant that must be carried to low earth orbit. Propellant transport is a principal cost item. Electric propulsion subsystems utilizing advanced ion thrusters are compared to magnetoplasmadynamic (MPD) thrust subsystems. For very large payloads, a large lift vehicle is needed to low earth orbit, and argon...
Topics: NASA Technical Reports Server (NTRS), EARTH ORBITS, NUCLEAR ELECTRIC PROPULSION, SOLAR ELECTRIC...
A history is given of low Earth orbit (LEO) laboratory test data on a 6.5 ampere-hour bipolar nickel hydrogen battery designed and built at the NASA Lewis Research Center. The bipolar concept is a means of achieving the goal of producing an acceptable battery, of higher energy density, able to withstand the demands of low-Earth-orbit regimes. Over 4100 LEO cycles were established on a ten cell battery. It seems that any perturbation on normal cycling effects the cells performance. Explanations...
Topics: NASA Technical Reports Server (NTRS), EARTH ORBITS, NICKEL HYDROGEN BATTERIES, SPACECRAFT ORBITS,...
The development of a noncontacting motion sensing system designed to monitor the movement of a cart along a track in the low earth orbit space environment is described. The system uses Hall effect sensors to detect the position of small permanent magnets located along the track. The measurement criteria are described, the system design is discussed, and estimates of the system error are given. The system will be used on the Crew and Equipment Translation Aid (CETA) experiment scheduled for the...
Topics: NASA Technical Reports Server (NTRS), AEROSPACE ENVIRONMENTS, ASTRONAUTS, CARTS, DETECTION,...
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236
Jul 12, 2010
07/10
by
Levine, S. H
texts
eye 236
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No Abstract Available
Topics: MISSION PLANNING, PAYLOADS, SPACE TUGS, VELOCITY, EARTH ORBITS, SPACE SHUTTLES, WEIGHT (MASS)
The analysis of the gamma-ray spectra taken from samples flown in Spacelab 1; the search for and review of neutron and proton activation cross-sections needed to analyze the results of the Long Duration Exposure Facility (LDEF) activation measurements; additional calculations of neutron induced activation for the LDEF samples; the data analysis plan for the LDEF and Spacelab 2 samples; the measurement of relevant cross-sections with activation of samples of V, Co, In, and Ta at the Indiana...
Topics: NASA Technical Reports Server (NTRS), ACTIVATION, EARTH ORBITS, LOW ALTITUDE, LOW EARTH ORBITS,...
206
206
Aug 2, 2010
08/10
by
Emslie, A. Gordo
texts
eye 206
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This report presents work performed between June 1990 and June 1991 and has the following objectives: (1) a comprehensive literature search of imaging technology and coded aperture imaging as well as relevant topics relating to solar flares; (2) an analysis of random number generators; and (3) programming simulation models of hard x ray telescopes. All programs are compatible with NASA/MSFC Space Science LAboratory VAX Cluster and are written in VAX FORTRAN and VAX IDL (Interactive Data...
Topics: FLIGHT TESTS, EARTH ORBITS, LIQUID METALS, LOW EARTH ORBITS, MIRRORS, SOLAR ENERGY, HEAT PIPES, ION...
Sizing data is presented for various combinations of Mars missions and chemical-propulsion/aerobraking vehicles. Data is compared for vehicles utilizing opposition (2-year mission) and conjunction (3-year mission) trajectories for 1999 and 2001 opportunities, for various sizes of vehicles. Payload capabilities for manned and unmanned missions vehicles and for propulsive-braking and aerobraking cases are shown. The effect of scaling up a reference vehicle is compared to the case of utilizing two...
Topics: NASA Technical Reports Server (NTRS), AEROBRAKING, CHEMICAL PROPULSION, MARS LANDING, ORBITAL...
A program was conducted to demonstrate the cycle life capability of welded solar cell modules relative to a soldered solar cell module in a simulated low earth orbit thermal environment. A total of five 18-cell welded (parallel gap resistance welding) modules, three 18-cell soldered modules, and eighteen single cell samples were fabricated using 2 x 4 cm silicon solar cells from ASEC, fused silica cover glass from OCLI, silver plated Invar interconnectors, DC 93-500 adhesive, and...
Topics: NASA Technical Reports Server (NTRS), SERVICE LIFE, SOLAR CELLS, SOLID STATE DEVICES, THERMAL...
The feasibility of developing and producing a launch vehicle from an external tank (ET) and an engine module that mounts inline to the tankage at the aft end and contains six space transportation main engines (STME), was assessed. The primary mission of this launch vehicle would be to place a PLS (personnel launch vehicle) into a low earth orbit (LEO). The vehicle tankage and the assembly of the engine module, was evaluated to determine what, if any, manufacturing/production impacts would be...
Topics: NASA Technical Reports Server (NTRS), BOOSTER ROCKET ENGINES, DESIGN ANALYSIS, EXTERNAL TANKS,...
328
328
May 29, 2011
05/11
by
Tai, Ann T.; Chau, Savio N.; Alkalai, Leo
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eye 328
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Using COTS products, standards and intellectual properties (IPs) for all the system and component interfaces is a crucial step toward significant reduction of both system cost and development cost as the COTS interfaces enable other COTS products and IPs to be readily accommodated by the target system architecture. With respect to the long-term survivable systems for deep-space missions, the major challenge for us is, under stringent power and mass constraints, to achieve ultra-high reliability...
Topics: TECHNOLOGY ASSESSMENT, GEOSYNCHRONOUS ORBITS, FLIGHT TESTS, ELLIPTICAL ORBITS, EARTH SCIENCES,...
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213
May 21, 2011
05/11
by
Stenholm, Sti
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A single mode cavity is deformed smoothly to change its electromagnetic eigenfrequency. The system is modeled as a simple harmonic oscillator with a varying period. The Wigner function of the problem is obtained exactly by starting with a squeezed initial state. The result is evaluated for a linear change of the cavity length. The approach to the adiabatic limit is investigated. The maximum squeezing is found to occur for smooth change lasting only a fraction of the oscillational period....
Topics: COST EFFECTIVENESS, LOW EARTH ORBITS, ORBIT TRANSFER VEHICLES, OXYGEN, PROPELLANT TRANSFER, SHUTTLE...
The Advanced Exploration Systems Program's Atmosphere Resource Recovery and Environmental Monitoring (ARREM) project is working to further optimize atmosphere revitalization and environmental monitoring system architectures. This paper discusses project management strategies that tap into skill sets across multiple engineering disciplines, projects, field centers, and industry to achieve the project success. It is the project's objective to contribute to system advances that will enable...
Topics: NASA Technical Reports Server (NTRS), ENVIRONMENTAL MONITORING, PROJECT MANAGEMENT, RELIABILITY,...
A presentation on the current status Educational Launch of Nano-Satellites and mission beyond low earth orbit.
Topics: NASA Technical Reports Server (NTRS), EDUCATION, SPACECRAFT LAUNCHING, NANOSATELLITES, LOW EARTH...
Low cost low Earth orbit (LOW) and geosynchronous Earth orbit (GEO) Solar Array concepts in the 300 to 1000 kW range which could be reduced to hardware in the mid 1980's, are identified. Size scaling factors and longer life demands are recognized as the prime drivers for the designs if low life cycle costs for energy are to be achieved. Technology is identified which requires further development in order to assure component readiness and availability. Use of the low concentration ratio (CR)...
Topics: NASA Technical Reports Server (NTRS), SATELLITE POWER TRANSMISSION, SATELLITE SOLAR POWER STATIONS,...
Equations are derived by using branched trajectory optimization techniques and the maximum principle to maximize the payload capability of a reusable tug/expendable kickstage vehicle configuration for planetary missions. The two stages and the payload are launched into a low earth orbit by a single space shuttle. The analysis includes correction for precession of the orbit. This correction is done by the tug. The tug propels the payload and the kickstage to an energy beyond earth escape and...
Topics: NASA Technical Reports Server (NTRS), EARTH ORBITAL RENDEZVOUS, EARTH ORBITS, ORBIT CALCULATION,...
