Coherent lidar can play a critical role in future planetary exploration missions by providing key guidance, navigation, and control (GNC) data necessary for navigating planetary landers to the pre-selected site and achieving autonomous safe soft-landing. Although the landing accuracy has steadily improved over time to approximately 35 km for the recent Mars Exploration Rovers due to better approach navigation, a drastically different guidance, navigation and control concept is required to meet...
Topics: NASA Technical Reports Server (NTRS), SOFT LANDING, OPTICAL RADAR, SPACE EXPLORATION, ROVING...
403
403
Jul 11, 2010
07/10
by
MASSON, A
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THE INSTALLATION FOR INVESTIGATIONS ON FULLSCALE OR LARGE-SCALE MODELS OF CONVENTIONAL AIRCRAFT OR CONVERTIPLANE PROPELLERS IN A LARGE SONIC WIND TUNNEL IS DESCRIBED. SOME EXAMPLES OF TESTS CARRIED OUT AND TYPICAL RESULTS OBTAINED ILLUSTRATE THE USE CAPABILITY OF THE EQUIPMENT, WHICH IS ALSO SUITABLE FOR HELICOPTER ROTOR TESTS.
Topics: AERODYNAMIC DRAG, ORBIT CALCULATION, SPACECRAFT CONTROL, TRAJECTORY ANALYSIS, ATMOSPHERIC DENSITY,...
Part III of this series of papers developed the theory of high eccentricity orbits (e 0.2) in an atmosphere having an exponential variation of air density with height, that is, with the density scale height H taken as constant. Part IV derived the appropriate theory for low-eccentricity orbits (e 0.2) in a more realistic atmosphere where H varies linearly with height y (and mu = dH/dy 0.2). The present report treats the orbits of Part III when they meet the air drag specified by the atmospheric...
Topics: DTIC Archive, King-Hele,D G, ROYAL AIRCRAFT ESTABLISHMENT FARNBOROUGH (ENGLAND), *ARTIFICIAL...
Aerobraking was an enabling technology for the Mars Odyssey mission even though it involved risk due primarily to the variability of the Mars upper atmosphere. Consequently, numerous analyses based on various data types were performed during operations to reduce these risk and among these data were measurements from spacecraft accelerometers. This paper reports on the use of accelerometer data for determining atmospheric density during Odyssey aerobraking operations. Acceleration was measured...
Topics: NASA Technical Reports Server (NTRS), ACCELEROMETERS, 2001 MARS ODYSSEY, AEROBRAKING, ATMOSPHERIC...
It has been proposed to utilize the Russian built SOYUZ as an assured crew return vehicle (ACRV) for Space Station Freedom. Three departure directions (nadir, zenith, minus velocity) are evaluated to determine escape path clearances. In addition, the effects of the following parameters were also evaluated: delta-V magnitude, configuration dependent ballistic coefficients, atmospheric density, Freedom attitude control, and canted docking adaptors. The primary factor influencing the escape...
Topics: NASA Technical Reports Server (NTRS), ESCAPE SYSTEMS, SOYUZ SPACECRAFT, SPACE STATION FREEDOM,...
This report describes the development test and calibration of a single proof mass three axis electrostatic accelerometer intended for atmospheric density measurements in an earth orbiting satellite.
Topics: DTIC Archive, Lange, William G., BELL AEROSPACE TEXTRON BUFFALO NY, *SPACECRAFT COMPONENTS,...
Aeolian activity was predicted for Mars from earth based observations of changing surface patterns that were interpreted as dust storms. Mariner 9 images showed conclusive evidence for aeolian processes in the form of active dust storms and various aeolian landforms including dunes and yardangs. Windspeeds to initiate particle movement are an order of magnitude higher on Mars than on Earth because of the low atmospheric density on Mars. In order to determine rates of abrasion by wind blown...
Topics: NASA Technical Reports Server (NTRS), ABRASION, ATMOSPHERIC DENSITY, DUST STORMS, MARS ATMOSPHERE,...
Atmospheric turbulence degrades a coherent laser beam when it propagates through the atmosphere. Measurements of the distribution of atmospheric turbulence provide insight into the underlying mechanisms that produce optical turbulence and suggest possible means to overcome or circumvent the effects of such turbulence. A variety of acoustic, optical and thermal probe instruments provide measurements of atmospheric turbulence. Of these, the acoustic echosounder can measure atmospheric density and...
Topics: DTIC Archive, Cherry, David R, NAVAL POSTGRADUATE SCHOOL MONTEREY CA, *TURBULENCE, *ATMOSPHERIC...
An extensive amount of neutral density data has been obtained from the highly successful accelerometer experiments on the Atmosphere Explorer -C, -D, and -E satellites. The accelerometer is electrostatically suspended and force rebalanced. Ground calibration requires sufficient suspension force to operate in the earth's 1g field. An important characteristic of the instrument is its null bias which is proportional to the suspension voltage. Null bias error is reduced when the instrument is in...
Topics: DTIC Archive, Marcos,Frank A, AIR FORCE GEOPHYSICS LAB HANSCOM AFB MASS, *ORBITS, *ACCELEROMETERS,...
Agora software is a simulation of spacecraft attitude and orbit dynamics. It supports spacecraft models composed of multiple rigid bodies or flexible structural models. Agora simulates multiple spacecraft simultaneously, supporting rendezvous, proximity operations, and precision formation flying studies. The Agora environment includes ephemerides for all planets and major moons in the solar system, supporting design studies for deep space as well as geocentric missions. The environment also...
Topics: NASA Technical Reports Server (NTRS), SIMULATION, SPACECRAFT CONTROL, SPACECRAFT MODELS, SYSTEMS...
This study of the upper atmosphere is based on 1980-85 twice daily gridded analysis produced by the European Centre for Medium Range Weather Forecasts. Included are global analyses of (1) Mean Temperature/Standard Deviation, (2) Mean Geopotential Height/Standard Deviation, (3) Mean Density/ Standard Deviation, (4) Height and Vector Standard Deviation. All for 13 pressure levels - 1000, 850, 700, 500, 400, 300, 250, 200, 150, 100, 70, 50, 30 mb. In addition, analyses of (5) Mean Dew...
Topics: DTIC Archive, Changery, Michael J, NATIONAL CLIMATIC DATA CENTER ASHEVILLE NC, *CLIMATE, *UPPER...
A statistical analysis of surface and upper air rawinsonde data is presented for Stallion Site, White Sands Missile Range, New Mexico. Atmospheric parameters covered for the layer from the surface to 100,000 feet above mean sea level are: Wind, temperature, pressure, density, moisture, index of refraction and freezing level. Upper air climatological information is based on the period of observation from 1961-1973; while the surface temperature data spans 1962- 1973, precipitation records...
Topics: DTIC Archive, Hoidale, Marjorie M, Dayton, Michael P, Newman, Lamar, ARMY ELECTRONICS COMMAND WHITE...
The ISS GNC system was updated recently with a new software release that provides onboard state determination capability. Prior to this release, only the Russian segment maintained and propagated the onboard state, which was periodically updated through Russian ground tracking. The new software gives the US segment the capability for maintaining the onboard state, and includes new GPS and state vector propagation capabilities. Part of this software package is an atmospheric density model based...
Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC DENSITY, ATMOSPHERIC MODELS, STATE VECTORS,...
NASA is concerned with protecting astronauts from the effects of galactic cosmic radiation and has expended substantial effort in the development of computer models to predict the shielding obtained from various materials. However, these models were only developed for shields up to about 120 g!cm2 in thickness and have predicted that shields of this thickness are insufficient to provide adequate protection for extended deep space flights. Consequently, effort is underway to extend the range of...
Topics: NASA Technical Reports Server (NTRS), GALACTIC COSMIC RAYS, RADIATION SHIELDING, RADIATION DOSAGE,...
Topics: DTIC Archive, Leviton, Robert, AIR FORCE CAMBRIDGE RESEARCH CENTER BEDFORD MA GEOPHYSICS RESEARCH...
682
682
Jun 13, 2011
06/11
by
Murthy, Pappu L. N.; Mital, Subodh K.; Gyekenyesi, John Z
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NASALife is a life prediction program for propulsion system components made of ceramic matrix composites (CMC) under cyclic thermo-mechanical loading and creep rupture conditions. Although, the primary focus was for CMC components the underlying methodologies are equally applicable to other material systems as well. The program references data for low cycle fatigue (LCF), creep rupture, and static material properties as part of the life prediction process. Multiaxial stresses are accommodated...
Topics: AEROCAPTURE, ANGLE OF ATTACK, ATMOSPHERIC DENSITY, FLIGHT SIMULATION, PROBABILITY THEORY, FLIGHT...
A simplified model of collection of charged particles by a flush mounted disk probe is presented. The model considers only collection of ions launched with a single fixed velocity normal to the collecting plane. It ignores collisions and space charge effects as well as the thermal distribution of the collected ions. The results of this model are compared with those of earlier, more detailed models, as well as with experimental results obtained from similar probes flown on rockets in the...
Topics: DTIC Archive, Sherman, Christopher, PHILLIPS LAB HANSCOM AFB MA, *CHARGED PARTICLES, *PARTICLE...
Defense Technical Information Archive
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DTIC ADA125194: 19319A MLRS, Missile Numbers BN-006, BN-003, BN-001, BN-004, BN-002, BN-005, Round Numbers V-390/DL-7, V-391/DL-08, V-392/DL-9, V-393/DL-10, V-394/DL-11, V-395/DL-12.
Jan 9, 2018
01/18
by
Defense Technical Information Center
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Meteorological data gathered for the launching of the 19319A MLRS, Missile Numbers BN-006, BN-003, BN-001, BN-004, BN-002, BN-005, Round Numbers V-390/DL-7, V-391/DL-08, V-392/DL-9, V-393/DL-10, V-394/DL-11, V-395/DL-12 are presented in tabular form. (Author)
Topics: DTIC Archive, Keller,Donald C, ARMY ELECTRONICS RESEARCH AND DEVELOPMENT COMMAND WSMR NM...
This report describes the design, development, fabrication and test of an analog voltage constrained electrostatic accelerometer to measure upper atmospheric density in an Air Force satellite designated S77-2. One accelerometer system and one set of Ground Support Equipment were delivered to AFGL in the course of this contract.
Topics: DTIC Archive, Lange, William G, BELL AEROSPACE TEXTRON BUFFALO NY, *ACCELEROMETERS, AERODYNAMIC...
Analysis of density measurements from the AE-E satellite have demonstrated that the local time variation in the thermosphere at low latitudes (20) changes from predominantly diurnal at thigh altitudes (about 300 km) to predominantly semidiurnal at low altitudes (about 140 km). This behavior is significant because it both affects the accuracy of density predictions at low satellite altitudes and confirms that the mesospheric semidiurnal tide is important to the dynamics of the lower...
Topics: DTIC Archive, Sharp,Lawrence R, AEROSPACE CORP EL SEGUNDO CALIF IVAN A GETTING LABS, *THERMOSPHERE,...
Statistical techniques have been developed which can be used to determine the effect of density and temperature on the trajectories of reentry vehicles for altitudes between the surface and 60 km. Arrays of monthly means and standard deviations of density and temperature at 2-km intervals of altitude to 60 km, together with interlevel coefficients of correlation of density with density and temperature, are provided for the mid-season months (January, April, July, October) at 10 locations...
Topics: DTIC Archive, Cole, Allen E., AIR FORCE GEOPHYSICS LAB HANSCOM AFB MA, *REENTRY VEHICLES, *DESCENT...
The work described in this report constitutes a data-processing and data analysis part of the AFGL SCRIBE (Stratospheric Cryogenic Interferometer Balloon Experiment) program. This work may be summarized into three major categories: (1) extraction of the interferogram data from the PCM telemetry data tape; (2) processing of the interferogram data for spectral retrieval; and (3) analysis of the obtained atmospheric emission data.
Topics: DTIC Archive, Sakai,Hajime, MASSACHUSETTS UNIV AMHERST ASTRONOMY RESEARCH FACILITY, *STRATOSPHERE,...
Laboratory experiments and theoretical calculations often use vertical impact angles (90 deg) in order to avoid the complicating effect of asymmetry. Nevertheless, oblique impacts represent the most likely starting condition for planetary cratering. Changing both impact angles and atmospheric pressure not only allows testing previous results for vertical impacts but also reveals phenomena whose signatures would otherwise be masked in the planetary cratering record. The laboratory studies were...
Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC EFFECTS, CRATERING, IMPACT LOADS, IMPACT TESTS,...
Lidars are of great interest because of their unique capabilities in remote sensing applications in sounding of the atmosphere, meteorology, and climatology. In this small business innovative research (SBIR) phase II program, laser sources including Co:MgF2, CTH:YAG, CTH:YSGG, CT:YAG, and Er:Glass were evaluated. Modulator of fused silica and TeO2 materials with Brewster's angle end faces were used with these lasers as acousto-optical (AO) Q-switches. A higher hold-off energy and hence a higher...
Topics: NASA Technical Reports Server (NTRS), AEROSOLS, ATMOSPHERIC DENSITY, ATMOSPHERIC SOUNDING, COBALT,...
Meteorological data gathered for the launching of the 12830B Lance, Missile Number 3331, Round Number 307 ESL, are presented in tabular form. (Author)
Topics: DTIC Archive, ARMY ELECTRONICS COMMAND WHITE SANDS MISSILE RANGE N MEX ATMOSPHERIC SCIENCES LAB,...
The feasibility of performing laser-Raman/Rayleigh scattering measurements in subsonic flows was demonstrated in the 6-in. Acoustic Research Tunnel (ART) of the Propulsion Wind Tunnel facility at AEDC. The ART is an open- circuit, atmospheric inbleed tunnel that operates on the Plenum Evacuation System of the 16-ft transonic Propulsion Wind Tunnel (16T). Laser-Raman/Rayleigh scattering techniques were used to measure air number density, H2O number density, and static temperature and to detect...
Topics: DTIC Archive, Williams, W D, ARNOLD ENGINEERING DEVELOPMENT CENTER ARNOLD AFB TN, *GAS FLOW, *RAMAN...
This abstract covers DCS III requirements, transmission media characteristics, regulatory factors, and DCS III transmission system alternatives. Appendix A documents results of transmission-media investigations. Appendix B presents a detailed review of rules, procedures, regulations, standards, and recommendations established by national/international organizations. Appendix C provides a description of topographic and climatic conditions in Germany, Turkey, and Hawaii.
Topics: DTIC Archive, Chu,T M, TRW DEFENSE AND SPACE SYSTEMS GROUP REDONDO BEACH CA, *SATELLITE...
Linearized hydrodynamic equations are solved for the time-dependent density perturbation caused by propagation of a high energy laser beam. The transverse flow of air through the beam (due to any combination of wind, laser platform motion and slew angular velocity) can have any desired time dependence, both in magnitude and direction. At any distance z along the beam the solution gives the variation in refractive index (proportional to the density variation) as a function of position in a plane...
Topics: DTIC Archive, Munn, M. W., Benson, R. S., LOCKHEED MISSILES AND SPACE CO INC PALO ALTO CA PALO ALTO...
Analysis presented here addresses a previous problem concerning free-flight projectiles governed by the two-dimensional, point mass equations representing drag as a power law. Down-range distance is taken to be the independent variable which yields a third-order differential equation governing the projectile's flight. An approximate solution is obtained which is shown to be very accurate for gun elevation angles up to 30 degrees. Previously examined engineering characteristics for flat fire are...
Topics: DTIC Archive, Cooper, Gene R, ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD WEAPONS AND MATERIALS...
An analysis of two X-ray absorption methods for determining small air-density gradients is presented. One method utilizes a Geiger-Mueller counter for detection and the other uses photographic film for detection. The methods are a refinement of a previous similar application. With the resulting sensitivity in density measurement, the first method was successfully applied to the evaluation of a 6-percent density gradient of a flat-plate boundary layer of about 0.024-inch thickness in a...
Topics: DTIC Archive, Weltmann, Ruth N, NATIONAL AERONAUTICS AND SPACE ADMINISTRATION CLEVELAND OH LEWIS...
This is a preliminary investigation of how perturbations to meteoroid shape or atmospheric density affect a meteor light curve. A simple equation of motion and ablation are simultaneously solved numerically to give emitted light intensity as a function of height. It is found that changing the meteoroid shape, by changing the relationship between the cross-section area and the mass, changes the curvature and symmetry of the light curve, while making a periodic oscillation in atmospheric density...
Topics: NASA Technical Reports Server (NTRS), ABLATION, METEOROID CONCENTRATION, PERTURBATION, SAMPLE...
During the launch countdown of the Ares I-X test vehicle, engineers from Langley Research Center will use profiles of atmospheric density and winds in evaluating vehicle ascent loads and controllability. A schedule for the release of balloons to measure atmospheric density and winds has been developed by the Natural Environments Branch at Marshall Space Flight Center to help ensure timely evaluation of the vehicle ascent loads and controllability parameters and support a successful launch of...
Topics: NASA Technical Reports Server (NTRS), ARES 1 LAUNCH VEHICLE, ASCENT TRAJECTORIES, ENVIRONMENTAL...
This annual report is concerned with work in progress on the development of a quantitative global model of the density of electrons, Ne, in the upper atmosphere. Knowledge of the ionosphere electron density is essential for the quantitative determination of radio wave propagation through this region of the earth's environment. Ultimately Ne will be described on a completely physical basis. This approach to the electron density problem has been taken by NRL and should eventually provide the best...
Topics: DTIC Archive, Olson,W P, MCDONNELL DOUGLAS ASTRONAUTICS CO-WEST HUNTINGTON BEACH CALIF, *ELECTRON...
The temperature profiles of micrometeors entering the atmospheres of Earth-like planets are calculated to determine the altitude at which exogenous organic compounds may be released. Previous experiments have shown that flash-heated micrometeorite analogs release organic compounds at temperatures from roughly 500 to 1000 K [1]. The altitude of release is of great importance because it determines the fate of the compound. Organic compounds that are released deeper in the atmosphere are more...
Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC ENTRY, ORGANIC COMPOUNDS, ATMOSPHERIC DENSITY,...
Many modern military systems used for communications, command and control, navigation, and surveillance depend on reliable and relatively noise- free transmission of radiowave signals through the earth's ionosphere. Small- scale irregularities in the ionospheric density can cause severe distortion, known as radiowave scintillation, of both the amplitude and phase of these signals. The WBMOD computer program can be used to estimate these effects on a wide range of systems. The objective of this...
Topics: DTIC Archive, Secan, James A, NORTHWEST RESEARCH ASSOCIATES INC BELLEVUE WA, *COMMUNICATION AND...
710
710
Jul 26, 2010
07/10
by
Lee, Jeh Wo
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The objective is the theoretical analysis and the experimental verification of dynamics and control of a two link flexible manipulator with a flexible parallel link mechanism. Nonlinear equations of motion of the lightweight manipulator are derived by the Lagrangian method in symbolic form to better understand the structure of the dynamic model. The resulting equation of motion have a structure which is useful to reduce the number of terms calculated, to check correctness, or to extend the...
Topics: AERODYNAMIC CHARACTERISTICS, AZIMUTH, CONTROL THEORY, CONTROLLERS, DOWNRANGE, PREDICTOR-CORRECTOR...
3,216
3.2K
May 23, 2011
05/11
by
NON
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The International GPS (Global Positioning System) Service for Geodynamics (IGS) supports and helps coordinate GPS data production and parameters useful for generating more accurate data products. The IGS has operated a GPS tracking system for several years. It contains more than 100 stations worldwide and has produced a combined GPS ephemeris that has become the standard for geodesists and geophysicists worldwide. IGS data and products are freely available to all, thanks to the cooperation and...
Topics: SOLAR ELECTRIC PROPULSION, COSTS, WEIGHT REDUCTION, MONOPROPELLANTS, COMPARISON, ATMOSPHERIC...
477
477
May 6, 2010
05/10
by
Ratcliffe, James G
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This technical publication details part of an effort focused on the development of a standardized facesheet/core peel debonding test procedure. The purpose of the test is to characterize facesheet/core peel in sandwich structure, accomplished through the measurement of the critical strain energy release rate associated with the debonding process. Following an examination of previously developed tests and a recent evaluation of a selection of these methods, a single cantilever beam (SCB)...
Topics: MARS ATMOSPHERE, SENSITIVITY, ATMOSPHERIC MODELS, TOPOGRAPHY, MARS (PLANET), TEMPERATURE,...
Meteorological data gathered for the launching of 19305AG GSRS, Missiles No. 1026, 1036, 1034, Rounds No. V-40, VO41, V-42, are presented in tabular form. (Author) 12
Topics: DTIC Archive, ARMY ELECTRONICS RESEARCH AND DEVELOPMENT COMMAND WSMR NM ATMOSPHERIC SCIENCES LAB,...
Meteorological data gathered for the launching of 12829C Lance, Missile Number 2479, Round Number 306 DST, are presented in tabular form. (Author)
Topics: DTIC Archive, ARMY ELECTRONICS COMMAND WHITE SANDS MISSILE RANGE N MEX ATMOSPHERIC SCIENCES LAB,...
The report contains a description of a U.S. Air Force Geophysics Laboratory Atmosphere Density experiment. Two instruments developed under an earlier program were qualified for space flight and were flown in the spring of 1978. Discussion of instrument performance and flight results are presented. (Author)
Topics: DTIC Archive, Accardo,Carl A, EPSILON LABS INC BEDFORD MA, *ATMOSPHERIC DENSITY, PRESSURE GAGES,...
This report describes the finalization of an extensive neutral atmospheric density data base taken from four satellite accelerometer systems; development of an empirical model of these data, circular orbit processing, AE-C re-entry data and contractual functions in support of the EUVS experiment. (Author)
Topics: DTIC Archive, Fioretti,Robert W, RDP INC WALTHAM MASS, *ACCELEROMETERS, *ARTIFICIAL SATELLITES,...
At high latitudes, dispersions in values of density for the middle atmosphere from the Global Reference Atmosphere Model (GRAM) are observed to be large, particularly in the winter. Trajectories have been run from 28.5 deg to 98 deg. The critical part of the atmosphere for reentry is 250,000 to 270,000 ft. 250,000 ft is the altitude where the shuttle trajectory levels out. For ascending passes the critical region occurs near the equator. For descending entries the critical region is in northern...
Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC DENSITY, DESCENT TRAJECTORIES, MIDDLE ATMOSPHERE,...
A summary of selected atmospheric conditions observed near space shuttle STS-31 launch time on April 24, 1990, at Kennedy Space Center, Florida, are presented. Values of ambient pressure, temperature, moisture, ground winds, visual observations (clouds), and winds aloft are included. The sequence of pre-launch Jimsphere-measured vertical wind profiles is also presented. The final atmospheric tape, which consists if wind and thermodynamic parameters versus altitude, for STS-31 vehicle ascent was...
Topics: NASA Technical Reports Server (NTRS), METEOROLOGICAL PARAMETERS, SPACE SHUTTLE ASCENT STAGE, SPACE...
Operational and research spacecraft require predictions of geomagnetic activity due to various effects of the geomagnetic activity on their operation. At high altitude, electrical charging of spacecraft surfaces, which occurs as a result of hot plasma injected from the geomagnetic tail during substorms, can produce discharges which result in spurious operation of the spacecraft. A reliable prediction of such activity can permit additional vigilance on the part of ground controllers at times of...
Topics: DTIC Archive, Vampola, Alfred L, AEROSPACE CORP EL SEGUNDO CA SPACE SCIENCES LAB, *ATMOSPHERIC...
Density data from the Satellite Electrostatic Triaxial Accelerometer (SETA) experiment were spectrally analyzed by the Maximum Entropy Method (MEM). The purpose is to make available a technique by which the occurrence of wavelike structures in thermospheric densities can be quantitatively analyzed and correlated with various geophysical conditions, including the deposition of energy at high latitudes during geomagnetically disturbed conditions. Spectra were computed for typical magnetically...
Topics: DTIC Archive, AIR FORCE GEOPHYSICS LAB HANSCOM AFB MA, *ACCELEROMETERS, *ATMOSPHERIC DENSITY,...
The effects of aerodynamic forces on trajectories at orbital speeds are discussed in terms of atmospheric models. The assumptions for the model are spherical symmetry, nonrotating, and an exponential atmosphere. The equations of flight, and the performance in extra-atmospheric flight are discussed along with the return to the atmosphere, and the entry. Solutions of the exact equations using directly matched asymptotic expansions are presented.
Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC ENTRY, HYPERSONIC FLIGHT, PLANETARY ATMOSPHERES,...
Composition data obtained by the quadrupole mass spectrometer (NACS) carried aboard the DE-B satellite were examined for variations in the polar regions during magnetically quiet conditions. The corresponding predictions of the MSIS-83 model are often used for comparison. The MSIS-83 model is used to emphasize the variations of interest by suppressing all other variations. A persistent enhancement of N2 density and a depletion of He density are present in the vicinity of the magnetic poles with...
Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC CHEMISTRY, ATMOSPHERIC COMPOSITION, ATMOSPHERIC...
This report describes the finalization of an extensive neutral atmospheric density data base taken from four satellite accelerometer systems; development of an empirical model of these data, circular orbit processing, AE-C re-entry data and contractual functions in support of the EUVS experiment. (Author)
Topics: DTIC Archive, Fioretti,Robert W, RDP INC WALTHAM MASS, *ACCELEROMETERS, *ARTIFICIAL SATELLITES,...
By use of a modified version of the CIAP UV Spectrophotometer, the altitude variation of 200-400 nm flux has been measured up to about 126 kft. Solar cycle associated variability of the flux in the important 220 nm region is discussed. Results are also given for direct measurement of air density in the 30-65 km region.
Topics: DTIC Archive, Sellers,Bach, PANAMETRICS INC WALTHAM MASS, *RADIATION ATTENUATION, *ATMOSPHERES,...
