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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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Dose-dependent depression of deoxyribonucleic acid study by x-ray irradiation and bromuracil deoxyriboside in mammalian cells
Experiments on earth and moon dealing with radio, optical, X-ray and gamma ray astronomy based on Lunar Exploration System for Apollo /LESA/ REPORT
Uv-induced dominant lethality, evidence for different lethal systems between uv and X-irradiation in Saccharomyces
Astronomical model of X ray sources in close binary systems
High angular resolution studies of celestial X ray sources and design of aspect camera, proportional collimators, telemetry, and attitude control systems
Model explaining X ray generation in close binary systems
X ray TV image enlargement system to perform inspections and failure analysis on electronic parts
X ray, extreme ultraviolet, H alpha, and radio emission from solar flares evaluated for use in satellite flare alarm system
Grazing incidence telescopes for X ray astronomy, describing mirrors, detection systems and dispersion techniques
Design, fabrication, installation, and operation of X ray diffractometer and X ray spectrograph system for preliminary examination of lunar soil sample within Lunar Receiving Laboratory
Design, development, fabrication, test, checkout, and support activities for delivery of integrated X ray and alpha particle spectrometer systems for lunar orbiter
From observation of the galactic structure in Cygnus, the system of filamentary nebulae was found to lie at a distance of roughly 1.5 kpc, in the same region as about half the thermal radio sources in Cygnus X, the supernova remnant near gamma Cygni, and the association Cygnus OB2, in the direction of which the X-ray source Cygnus XR-3 is observed. The source of excitation was probably the pulse of radiation from a supernova explosion, as proposed in the case of Gum nebula. However continuing excitation by early stars in the region of Cygnus X cannot be excluded.
Phase 2 (development) which was concluded for the ultrasonic Doppler device and the light-pipe-reflectance device is reported. An ultrasonic Doppler breadboard system was assembled which accurately measured runout in the J-2 LOX pump impeller during operation. The transducer was mounted on the outside of the pump volute using a C-clamp. Vibration was measured by conducting the ultrasonic wave through the volute housing and through the fluid in the volute to the impeller surface. The impeller vibration was also measured accurately using the light-pipe probe mounted in an elastomeric-gland fitting in the pump case. A special epoxy resin developed for cryogenic applications was forced into the end of the fiber-optic probe to retain the fibers. Subsequently, the probe suffered no damage after simultaneous exposure to 2150 psi and 77 F. Preliminary flash X-radiographs were taken of the turbine wheel and the shaft-bearing-seal assembly, using a 2-megavolt X-ray unit. Reasonable resolution and contrast was obtained. A fast-neutron detector was fabricated and sensitivity was measured. The results demonstrated that the technique is feasible for integrated-time measurements requiring, perhaps, 240 revolutions to obtain sufficient exposure at 35,000 rpm. The experimental verification plans are included.
Glancing incidence telescopes of the kind first described by Wolter have now been physically realized, so that it is possible to obtain high-resolution images of celestial objects at all wavelengths greater than about 3 A. The GSFC-MSFC X-ray telescope for the Apollo telescope mount uses Wolter type 1 optics and is capable of forming images of the sun in the 8-70 A region with spatial resolution of the order of one arc second. The GSFC extreme ultraviolet spectroheliometer for OSO H uses type 2 optics and can obtain images of the sun in spectral lines in the 170-400 A region with a spatial resolution of about ten arc seconds. Theoretical (ray trace) and laboratory data on these systems are presented.
Observations of Cygnus X-1 (probably in eclipse) and Cygnus X-2 on Oct. 23, 1971, show quite low absorption in their spectrum, and yet they are thought to be in a double or multiple star system from the optical data. The lack of intrinsic absorption in their spectra may be taken to mean that they lie sufficiently far from their primaries for a reduction to virtually zero of their interaction with the atmosphere of the primaries.
A survey of our own galaxy and neighboring galaxies using X-rays, gamma rays, and cosmic rays is outlined. High energy astrophysic results suggest the presence of a new acceleration mechanism where the inflow of matter on collapsed objects seems to be one of the sources of complex time variations in binary systems.
Photographic spectra of Cen X-3 show that the primary star has a spectral type near 06.5 with weak, variable emission at wavelength 4640 and 4686. No orbital motion of the emission or absorption lines is detected; for the latter the upper limit is approximately + or - 50 km/s. Analysis of the available data indicates that the primary is a factor of 2-3 less massive than expected from normal evolutionary models while the X-ray source has a solar mass near 1.5.
The proceedings of a symposium on significant accomplishments in science and technology are presented. The symposium was held at the Goddard Space Flight Center in December 1973. The subjects discussed are as follows: (1) cometary physics, (2) X-ray and gamma ray astronomy, (3) solar and terrestrial physics, (4) spacecraft technology, (5) Earth Resources Technology Satellite, (6) earth and ocean physics, (6) communications and navigation, (7) mission operations and data systems, and (8) networks systems and operations.