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Whitehead, A. B.

Publications and source records attributed to Whitehead, A. B..

12 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1981

Silicon-on-ceramic process: Silicon sheet growth and device development for the large-area silicon sheet task of the low-cost solar array project

The technical feasibility of producing solar cell quality sheet silicon to meet the DOE 1986 cost goal of 70 cents/watt was investigated. The silicon on ceramic approach is to coat a low cost ceramic substrate with large grain polycrystalline silicon by unidirectional solidification of molten silicon. Results and accomplishments are summarized.

Whitehead, A. B.↗
NASA NTRS1980

Method and means for helium/hydrogen ratio measurement by alpha scattering

An apparatus for determining helium to hydrogen ratios in a gaseous sample is presented. The sample is bombarded with alpha particles created by a self contained radioactive source and scattering products falling within a predetermined forward scattering angular range impact a detector assembly. Two detectors are mounted in tandem, the first completely blocking the second with respect to incident scattering products. Alpha particle/hydrogen or alpha particle/helium collisions are identified by whether scattering product impacts occur simultaneously in both detectors or only in the first detector. Relative magnitudes of the two pulses can be used to further discriminate against other effects such as noise and cosmic ray events.

Whitehead, A. B.↗
NASA NTRS1974

The elevation of Olympus Mons from limb photography

Using a novel photogrammetric technique, the relative elevations of a set of control points on the Martian volcano Olympus Mons (Nix Olympica) have been measured from Mariner 9 limb pictures that include the volcano in the foreground. The summit of Olympus Mons is found to be 22 plus or minus 1 km above the mean level of the surrounding plain by correlating the elevation results with previously reported planet radii at nearby occultation points. Vertical elevation differences as great as 5 km were measured between close points on the basal scarp.

Whitehead, A. B.↗
NASA NTRS1973

Project objectives and mission profile

Mission planning, payloads, launch, and orbital insertion are described for Mariner mission 8 and 9. Mission sequences and planet coverage as a function of time in orbit are discussed.

Steinbacher, R. H.↗
NASA NTRS1973

Television experiment

The fixed and variable Martian features investigated by the TV experiment on Mariner 9 are described. Articles are presented concerning the dust storm of October to November over the Southern Hemisphere; global surface geodesy and cartography; geology; and the satellite astronomy.

Briggs, G. A.↗
NASA NTRS1973

Surface properties working group

The objectives of the Mars surface properties working group are described. The objectives were: (1) determine a simple reference surface that would adequately represent the shape of the planet for cartographic purposes; (2) monitor the topographic results and to assess the relative calibration and accuracies of these techniques, thereby leading to a composite topographic map of the planet; and (3) facilitate the exchange of data in closely connected disciplines. The shape, topography, and isobaric surface are discussed along with the gravity field, and crustal density model. It was found that there is no simple reference figure for the planetary surface, although an offset, triaxial ellipsoid is adequate for most purposes.

Whitehead, A. B.↗