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Smith, J.

Publications and source records attributed to Smith, J..

At least 109 records · Page 6
All sourcesNASA NTRSDOE OSTI
NASA NTRS1984

NLR activities in the field of wind tunnel wall interference

Measured field data as a boundary condition for calculating the interference flow field were applied. They are divided into two categories. In the first category, the field data must consist of distributions of a single velocity component, and an accurate estimate of the hypothetical free air contribution of the model to this component is required. The differences between measured values and estimated model contributions are attributed to wall interference and they establish the boundary condition. The associated field data measurements are simple, yet the necessary model representation generally is a serious drawback. The second category requires field data which consist of velocity vector distributions at the price of multicomponent measurements, but at the profit that no information at all is required about the model. In solid wall test sections, the price is reduced to virtually zero but the profit remains.

Smith, J.↗
NASA NTRS1983

Far-infrared observations of the type 1 Seyfert galaxy NGC 4051

The Kuiper Airborne Observatory was used, together with a seven-element array, in measurements of the far-IR flux from the Seyfert galaxy NGC 4051. Flux densities within and outside of the central region were found to be comparable, with a possible local peak of emission in the west, and a total far-IR luminosity of 3.4 + or - 0.8 billion solar luminosities. The spectral shape of the radiation and its extended distribution, together with data at other wavelengths, suggest that the IR emission arises from warm dust. The relatively weak IR flux, and the apparent lack of dust and gas by comparison to the total (virial) material, indicate less active star formation than that found in such galaxies as the type 2 Seyfert, NGC 1068.

Smith, H. A.↗
NASA NTRS1983

Dispensing Small Measured Volumes of Liquid

Dispensing unit measures, filters, and unloads oil into container. Used in automobile manufacturing to dispense antifreeze solution into radiators or oil into engines, transmissions, or differentials. Uses gaseous nitrogen to control pressure, flow rate, and quality precisely, with minimal contamination from atmosphere.

Larson, G.↗
NASA NTRS1983

A large aperture balloon-borne telescope for a submillimeter wavelength survey of the galactic plane

A balloon-borne, 1.2 meter Cassegrain telescope with a servo-controlled chopping secondary mirror has been developed and used to survey the Galactic Plane at submillimeter wavelengths. The telescope pointing system uses a gyroscope as the primary stabilization reference and makes use of microprocessors for pointing control, on-board data collection, and telemetry formatting. A description of the telescope, multi-channel liquid-helium-cooled focal plane and the aspect and orientation subsystems are presented.

Silverberg, R. F.↗
NASA NTRS1982

The far-infrared disk of M51

Far-infrared maps and multifrequency photometry are presented for M51 and its companion galaxy NGC 5195. Dust reradiates about half the starlight of the M51 + NGC 5195 system to produce the observed far-infrared (80-200 microns) luminosity of 3 x 10 to the 10th solar luminosities. Observed with 49-arcsec resolution and covering 37 arcmin-squared, the maps show that roughly 70% of this luminosity is produced by the 5 arcmin (approximately 15 kpc) wide far-infrared disk of M51. Comparable luminosities emitted from the central regions (diameters = 49 arcsec or 2.3 kpc) of M51 and NGC 5195 contribute the remaining 30% (approximately 1 x 10 to the 10th solar luminosities). The photometry reveals a difference in energetics at the galactic scale; dust producing the central luminosity of NGC 5195 classified as Ip-Ep, Irr II or SBa(r) is much less abundant and considerably warmer than the approximately 20 K dust producing the central luminosity of M51 (Sc I). Far-infrared properties are given for several galactic scale complexes of star formation in M51. Relationships are discussed for selected maps of optical starlight and emissions from these components of M51's interstellar medium: dust grains, CO molecules, hydrogen atoms, electrons, and H II regions.

Smith, J.↗
NASA NTRS1982

Far-infrared observations of FU Orionis

The peculiar star FU Orionis is located in the southeast extension of Barnard 35 (B35), a bright-rimmed molecular cloud, and in the more extended, low-density region around Lambda Orionis. In connection with the present investigation, far-infrared observations of the star were undertaken in order to obtain a better estimate of the total luminosity of FU Ori and to better understand its relationship with the B35 cloud. FU Orionis was observed on 1981 January 23 with the 90 cm telescope on board the NASA Kuiper Airborne Observatory. The far-infrared results suggest that much of the radiation from the stellar source does not interact with either the 225 K circumstellar dust or the exterior 15 K material. The total luminosity of FU Ori is now seen to be about the same as the visible luminosity, and at the distance to B35 ridge dilution would make any isotropic effects negligible.

Smith, H. A.↗
NASA NTRS1981

Far-infrared and submillimeter observations of Barnard 35 - Heat sources for bright-rimmed molecular clouds

Far-infrared and submillimeter continuum observations of a region of enhanced gas temperature in Barnard 35 are presented which were obtained in a study of dust and gas energetics in the bright-rimmed molecular cloud. Observations were obtained with the 90-cm telescope on board the NASA Kuiper Airborne Observatory, together with ground-based observations of the CO lines. The spectrum is found to correspond to a dust temperature of 10 + or - 5 K. A total dust luminosity of about 69 solar luminosities is estimated for the cloud, which may easily be supplied by stellar radiation from the background field or the Lambda Ori cluster. Observations of CO emission at 2.7 mm indicate a gas temperature of 23.4 + or - 3.5 K. The difference between the gas and dust temperatures confirms earlier suggestions that the gas and dust are not in thermal equilibrium and that gas-dust collisions are not the heat source for the molecular gas, however the actual source of the molecular gas heating remains uncertain.

Lada, C. J.↗
NASA NTRS1981

Multichannel scanning radiometer for remote sensing cloud physical parameters

A multichannel scanning radiometer developed for remote observation of cloud physical properties is described. Consisting of six channels in the near infrared and one channel in the thermal infrared, the instrument can observe cloud physical parameters such as optical thickness, thermodynamic phase, cloud top altitude, and cloud top temperature. Measurement accuracy is quantified through flight tests on the NASA CV-990 and the NASA WB-57F, and is found to be limited by the harsh environment of the aircraft at flight altitude. The electronics, data system, and calibration of the instrument are also discussed.

Curran, R. J.↗
NASA NTRS1980

Far-infrared photometry of Titan and Iapetus

Titan was observed in four broad passbands between 35 and 150 microns. The brightness temperature in this interval is roughly constant at 76 plus or minus 3 K. Integrating Titan's spectrum from 5 to 150 microns yields an effective temperature of 86 plus or minus 3 K. Both the bright and dark hemispheres of Iapetus were observed in one broadband filter with a flux-weighted mean wavelength approximately equal to 66 microns. The brightness temperatures for these two sides of Iapetus are 96 plus or minus 9 K and 114 plus or minus 10 K, respectively. The bright-side Bond albedo is calculated to be 0.61(+0.16;-0.22).

Loewenstein, R. F.↗
NASA NTRS1979

Far infrared maps of the ridge between OMC-1 and OMC-2

Dust continuum emission from a 6 ft x 20 ft region surrounding OMC-1 and OMC-2 were mapped at 55 and 125 microns with 4 ft resolution. The dominant features of the maps are a strong peak at OMC-1 and a ridge of lower surface brightness between OMC-1 and OMC-2. Along the ridge the infrared flux densities and the color temperature decreases smoothly from OMC-1 to OMC-2. OMC-1 is heated primarily by several optical and infrared stars situated within or just at the boundary of the cloud. At the region of minimum column density between OMC-1 and OMC-2 the nearby B0.5 V star NU Ori may contribute significantly to the dust heating. Near OMC-2 dust column densities are large enough so that, in addition to the OMC-2 infrared cluster, the nonlocal infrared sources associated with OMC-1 and NU Ori can contribute to the heating.

Keene, J.↗
NASA NTRS1977

Multistack nickel-hydrogen units

A typical 625 Inconel pressure vessel, equipped with four thermocouples, has voltage taps not only for the cell, but for each of the several packs inside the container. In a two-stack design, a weld ring is used to separate the packs which, joined together, form one solid group. In the four-stack design, stacks are separated mechanically with about half inch Plexiglas and are connected through the center. Electrolytes are forced out by vacuum. The two stack design is intended for 500 psi and was pressure tested up to 1,000. The problem of electrolyte shorts is discussed and possible solutions for its correction are given.

Smith, J.↗
NASA NTRS1975

Preflight studies on tolerance of pocket mice to oxygen and heat. I - Physiological studies

Tests were carried out on pocket mice to ascertain their tolerance to elevated oxygen pressures alone and to a combination of hyperoxia and heat in excess of that expected during the flight of the mice on Apollo XVII. The mice withstood oxygen partial pressures up to 12 psi at normal room temperature (24 C, 75 F) over a period of 7 days. A few mice previously exposed to increased PO2 died in the course of exposure to an oxygen pressure of 10 psi or 12 psi (517 mm or 620 mm Hg) for 13 d in ambient heat of 32 C (90 F). Supplemental vitamin E and physiological saline loading given prior to exposure had no apparent protective effect. The overall conclusion was that the pocket mice which were to go on Apollo XVII could readily survive the ambient atmosphere to which they would be exposed.

Leon, H. A.↗
NASA NTRS1975

Application of spatial features to satellite land-use analysis

A Level I land-use analysis of selected training areas of the Colorado Front Range was carried out using digital ERTS-A satellite imagery. Level I land-use categories included urban, agriculture (irrigated and dryland farming), rangeland, and forests. The spatial variations in spectral response for these land-use classes were analyzed using discrete two-dimensional Fourier transforms to isolate and extract spatial features. Analysis was performed on ERTS frame 1352-17134 (July 10, 1973) and frame number 1388-17131 (August 15, 1973). On training sets, spatial features yielded 80 to 100 percent classification accuracies with commission errors ranging from 0 to 20 percent.

Smith, J.↗
NASA NTRS1970

Data relay satellite phased array

S band communications repeater using retrodirective phased array on synchronous altitude data relay satellite /DRS/ for intersatellite and ground links

Dod, L. R.↗