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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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Ion-polar molecule collision time history plots and computer movies, calculating capture cross sections for mass spectrometry
Apollo 11 lunar soil irradiation history from solar wind rare gas abundances and cosmic ray spallation products
Apollo 11 lunar rocks, breccia and fines U, Th and Pb isotopes systematics, considering implications for lunar history
Preferred disorder and shock histories of chemical group 4A meteorites from metallographic and X ray diffraction, discussing preterrestrial shock loading
NACA/NASA rotating wing aircraft research history 1915-1970, Part 2, autogyro flight test experiences, rotor blade dynamics research, interest in helicopters, etc
NACA/NASA rotary wing aircraft research history 1915-1970, Part 3, covering rotor and helicopter theory, related flight and wind tunnel testing, etc
NACA/NASA rotating wing aircraft research history 1915-1970, Part 3, covering rotor dynamics and flying qualities, hovering tests, rotor flow, loads, etc
NACA/NASA rotating wing aircraft research history during 1955-1970 period, discussing wind tunnel research
Sonic boom wave pressure history prediction on arbitrarily oriented plane walls by explicit fixed mesh time dependent numerical method
Sliding load history effects on friction of thin burnished films of molybdenum disulfide in vacuum
Oxidation state of iron and cation distribution over M1 and M2 sites in clinopyroxenes from Apollo 12 by Mossbauer absorption spectroscopy, noting cooling history
Clinopyroxene crystallization histories of Apollo 12 porphyritic basalt rocks 12021 and 12052 from Oceanus Procellarum
Size distribution, composition and history of regolith fines at Apollo 12 site
Lunar surface history model, discussing mascons, chemical composition, isochron ages and seismic and electrical properties of samples
Apollo 11 and 12 lunar samples history of irradiation exposure to galactic cosmic rays and solar wind, using rare gas and Gd isotope measurements
Radiation exposure history from fossil tracks in Apollo 12 surface rocks and double core regolith samples, comparing with Saint Severin meteorite
Lunar anorthosite 15415 consists almost entirely of anorthite (homogeneous anorthite 96.6 molecule percent), with accessory diopsidic augite and traces of hypersthene, ilmenite, and a silica mineral. The rock has had a complex metamorphic history. The texture reflects at least two episodes of shearing (followed by intense and partial recrystallization, respectively), one episode of cataclastic deformation, and one or more episodes of shattering and fragmentation.
This paper considers the extent to which Martian craters can be explained by considering asteroidal impact. Sections I, II, and III of this paper derive the diameter distribution of hypothetical asteroidal craters on Mars from recent Palomar-Leiden asteroid statistics and show that the observed Martian craters correspond to a bombardment by roughly 100 times the present number of Mars-crossing asteroids. Section IV discusses the early bombardment history of Mars, based on the capture theory of Opik and probable orbital parameters of early planetesimals. These results show that the visible craters and surface of Mars should not be identified with the initial, accreted surface. A backward extrapolation of the impact rates based on surviving Mars-crossing asteroids can account for the majority of Mars craters over an interval of several aeons, indicating that we see back in time no further than part-way into a period of intense bombardment. An early period of erosion and deposition is thus suggested. Section V presents a comparison with results and terminology of other authors.