Computations for the improvement of global atmospheric models
Global atmospheric models computations based on treating molecular and eddy diffusion as dynamic processes
Devries, L. L.↗
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Comets, meteorites and the moon
Properties, photometry, and dynamic processes of comets, lunar morphology, and Tungusk meteorite blast
Dergachev, V. A.↗
Dynamical analysis of outflow from tornado- producing thunderstorms as revealed by ATS III pictures
Tornado producing thunderstorms upper level outflow synoptic and dynamic processes from ATS 3 pictures, discussing convective warming effects
Ninomiya, K.↗
A global empirical model of thermospheric composition based on OGO-6 mass spectrometer measurements
The analysis of composition measurements made with the neutral mass spectrometer aboard the OGO-6 satellite leads to the following conclusions. The measured atomic oxygen densities are generally in good agreement with those deduced from drag. The molecular nitrogen densities in the annual and semiannual variations depart significantly from those predicted by drag models and suggest similar departures for exospheric temperatures. The helium densities generally tend to vary in an inverse manner to the nitrogen densities. These composition changes are consistent with dynamical processes associated with the global circulation in the thermosphere.
Hedin, A. E.↗
Analysis of inner and outer zone: OGO-1 and OGO-2 electron spectrometer and ion chamber data
The dynamic processes governing the acceleration and loss of electrons in the radiation zones are investigated. The radial diffusion coefficient was determined for a McIlwain parameter between 1.6 and 2.2 for electrons having a first adiabatic invariant of 12 MeV/gauss. The coefficient is larger than earlier values and suggests that there exists a lower limit to the fluxes in the inner zone. The agreement between observed and calculated magnetic fields and particle fluxes is improved by using solar wind pressure as input to the magnetic field models. Changes in the plasma pressure can cause apparent local time asymmetries in particle flux. A comparison of the magnetic field models with observed location of the trapping boundary also indicates the need for including distributed currents within the magnetosphere. The high latitude trapping boundary is only weakly dependent on A sub p, and the trapping boundary data are improved by including in the models a stand-off distance which varies with the plasma pressure.
Pfitzer, K. A.↗
Neutral composition variation above 400 kilometers during a magnetic storm.
Examination of data from the neutral atmospheric composition experiment launched aboard Ogo 6, June 5, 1969, for the period from Sept. 27 through Oct. 3, 1969. Several magnetic storms occurred during this time, and the response of the neutral atmosphere to the energy deposition causing these storms was studied. The data indicate that the major portion of the energy is deposited at high latitudes, causing enhancements in N2 densities corresponding to Jacchia (1970) temperature increases on the order of 400 to 500 K. The time difference between atmospheric response and magnetic activity appears to be very short at high latitudes. The O/N2 ratio variations suggest dynamic processes that cause a circulation in the atmosphere that is upward at the pole with subsidence at the equator.
Taeusch, D. R.↗
Outer planets grand tours: Planetary radio astronomy team report
Requirements related to scientific observations of planetary radio emissions during outer planets grand tours are discussed. Observations at low frequencies where non-thermal cooperative plasma phenomena play a major role are considered for determining dynamical processes and magnetic fields near a planet. Magnetic field measurements by spacecraft magnetometers, and by radio receivers in their harmonic modes are proposed for interpretation of planetary radio emission.
Warwick, J. W.↗
Postflight simulation of parachute deployment dynamics of Viking qualification flight tests
Simulation calculations of the Viking qualification flight tests are conducted by use of analytical models of the parachute deployment dynamics process. Results from the study indicate that good simulations of event times and trajectory are obtained. If the full-scale parachute drag coefficient is used, a good simulation of first opening load is obtained and the overall nature of the load history is calculated. For longitudinal motions, the two-degree-of-freedom models give good agreement with a six-degree-of-freedom model. It is believed that the analytical models used are tools which will aid in the analysis of future flight systems.
Whitlock, C. H.↗
Development of propulsion for high atmospheric pressure or dense environments
The development of a propulsion system that employs a detonating propellant is described, and the need for such a system and its use in certain planetary atmospheres are demonstrated. A theoretical formulation of the relevant gas-dynamic processes was developed, and a related series of experimental tests were pursued.
Varsi, G.↗
S-band radio occultation measurements of the atmosphere and topography of Mars with Mariner 9: Extended mission coverage of polar and intermediate latitudes
Radio occultation measurements from Mariner 9 orbits around Mars show that the radius of Mars changes by only about 2 km from a latitude of 65 deg to the north pole, that the north polar area is about average in elevation, and that polar temperature profiles are indicative of the possibility that the remnant north polar cap may be at least partially composed of water ice. It is also found that Mars, in addition to being asymmetrical equatorially, is also significantly asymmetrical in the north and south direction with the Southern Hemisphere lying 3 to 4 km higher. Temperature gradients in the clear Martian atmosphere of only about one-half of the adiabatic gradients of 5 deg K/km suggest the importance of dynamical processes.
Kliore, A. J.↗
Miniature biotelemeter giving 10 channels of wideband biomedical data.
A miniature biotelemeter has been developed for sensing and transmitting multiple channels of wideband biomedical data over a radio link. Its small size and weight make it capable of being carried by free-moving laboratory animals as small as rats. Ten data channels each of 5-kHz data bandwidth are provided to permit monitoring of a wide variety of physiological signals. Multichannel telemetry of electroencephalograms, electrocardiograms, electromyograms, state functions, and dynamic processes such as blood flow and body chemistry are possible applications. Utilization of newly available monolithic chip components, low-power COS/MOS MSI digital logic, and state-of-the-art hybrid mounting techniques makes this novel device useful for both research and clinical bioinstrumentation.
Carraway, J.↗
Moonquakes and lunar tectonism results from the Apollo passive seismic experiment.
The natural seismicity of the moon appears to be very low relative to that of the earth. However, moonquakes do occur. They are detected by the stations of the Apollo seismic network at an average rate of 1800/yr at Station 14 and at lower rates at Stations 12 and 15. All of the moonquakes are small, and in the few cases for which the foci have been located, they occur at great depth (about 800 km). The frequency of occurrence of moonquakes is strongly correlated with lunar tides. The dynamic processes that generate quakes are clearly much less vigorous within the moon than they are within the earth.
Latham, G.↗
On the kinetic temperature of He/++/ in the solar wind.
Observations of solar-wind He(++) can be useful for studying dynamical processes in the interplanetary medium. Several processes which may influence the kinetic temperature are considered, and an attempt is made to inquire whether they can account for the observed fact that the kinetic temperature exceeds the proton temperature. Resonant heating is discussed qualitatively, and equations of resonant heating are developed. The proton and He(++) heating rates are determined for the least damped magnetoacoustic wave under various conditions.
Barnes, A.↗
Radio physics of the outer solar system.
The remote sensing of low frequency nonthermal radio emission is the astronomy of field and particle phenomena. Observations conducted from space lead to information about the composition and dynamic processes occurring in planetary magnetospheres as well as within the interplanetary and interstellar medium. The potential of this technique is demonstrated by considering observations obtained from earth orbit missions.
Stone, R. G.↗
Some recent developments in cometary physics.
Recent observations and associated theoretical developments bearing on the composition and structure of comets are briefly reviewed. The physical and dynamical processes in cometary atmospheres and ionospheres are discussed, and detailed hydrodynamic models of expanding multiconstituent cometary atmospheres corresponding both to a central nucleus as well as a central nucleus surrounded by a distributed source are presented for comparison with observation. It is argued that observed 'slow' speed for the neutral hydrogen is not incompatible with a purely H2O 'parent' source for that species.
Mendis, D. A.↗
Utilization of ERTS-1 data in North Carolina
The author has identified the following significant results. ERTS-1 imagery has been used to study forested wetlands, dynamic processes off Coastal North Carolina, and land use patterns in the Wilmington, North Carolina area. The thrust of the investigation is still involvement of state and regional agencies in the use of ERTS-1 imagery in solving some of their day-to-day problems.
Welby, C. W.↗
Friction and wear characteristics of carbon steels in vacuum
The nature of carbon steel friction and wear under vacuum conditions is described within the framework of general friction and wear theory. Friction is considered a dynamic process and wear is considered to be the result of a continuous sequence of transitions of the friction surface material from one state into another.
Verkin, B. I.↗
Studies in the use of cloud type statistics in mission simulation
A study to further improve NASA's global cloud statistics for mission simulation is reported. Regional homogeneity in cloud types was examined; most of the original region boundaries defined for cloud cover amount in previous studies were supported by the statistics on cloud types and the number of cloud layers. Conditionality in cloud statistics was also examined with special emphasis on temporal and spatial dependencies, and cloud type interdependence. Temporal conditionality was found up to 12 hours, and spatial conditionality up to 200 miles; the diurnal cycle in convective cloudiness was clearly evident. As expected, the joint occurrence of different cloud types reflected the dynamic processes which form the clouds. Other phases of the study improved the cloud type statistics for several region and proposed a mission simulation scheme combining the 4-dimensional atmospheric model, sponsored by MSFC, with the global cloud model.
Fowler, M. G.↗