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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Observations of v.h.f.-bistatic-aurora-backscatter-communications on 145 Mc/s within Middle Europe and from Middle Europe to Great Britain and Scandinavia covering the period from 1957 to the beginning of 1963 are analyzed with respect to the probability of occurrence of these phenomena as a function of the magnetic dip angle and the degree of geomagnetic activity. An interpretation is given of the obtained results.
Penetration rates and meteoritic encounter frequency obtained from explorer xiii and explorer xvi satellites to reappraise meteoroid hazards to spacecraft
Penetration rates and meteoritic encounter frequency obtained from explorer xiii and explorer xvi satellites to reappraise meteoroid hazards to spacecraft
Meteoroid hazard to thin stainless steel skin - explorer xiii satellite penetration rate data
Explorer XIII satellite - copper-wire-card micrometeoroid detectors
Explorer XIII satellite - cadmium sulfide experiment for micrometeoroid detection
Explorer XIII satellite meteoroid-particle impact-detection experiment
Explorer XIII satellite - pressurized-cell detectors for measurement of micrometeoroid puncture hazard
Explorer XVIII satellite Interplanetary Monitoring Platform /IMP/ measurements of magnetic fields, cosmic rays, solar wind, and lunar magnetosphere shock wave
The basic telemetry-system concept for Explorer XI11 was selected primarily on the basis of demonstrated performance (ref. IV-1). The successful orbiting of Vanguard I1 (1939 Alpha) and Vanguard I11 (1959 Eta) had proven the basic design of the tracking and telemetry concepts which were compatible with mini- track network. It was necessary for the NASA Langley Research Center (LRC) to expand the system to provide a 48-channel telemetry system. Two of these sys- tems were used in the Explorer XI11 in order to provide the required channel capacity.
Explorer XIII power-supply systems and test solar cells
Meteoroid hazard data used for snap design from explorer xiii and xvi satellite observations
We present an analysis of Chandra grating spectra of k ey helium-lik e line comple x es to put constraints on the location with respect to the photosphere of the hottest ( T 6 ×10 6 K) plasma in the wind of the O supergiant ζPup and to explore changes in the 18 yr between two sets of observations of this star. We fit two models –one empirical and one wind-shock-based –to the S XV , Si XIII , and Mg XI line comple x es and show that an origin in the wind flow, abo v e r ≈1.5 R ∗, is strongly fa v oured o v er an origin less than 0.3 R ∗abo v e the photosphere ( r 1.3 R ∗), especially in the more recent, very long-exposure data set. There is a modest increase in the line and continuum fluxes, line widths, wind absorption signatures, and of the hot plasma’s distance from the photosphere in the 18 yr since the first Chandra grating observation of ζPup. Both modes of modelling include the effects of dielectronic recombination satellite emission line blending on the helium-like comple x es –the first time this has been accounted for in the analysis of He-like line ratios in O stars.