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Optimization of three-stage matrices, modularization, and black boxes design techniques provides for automatically interconnecting computing component inputs and outputs in general purpose analog computer. Design also produces relatively inexpensive and less complex automatic patching system.
The ionizing light of the supernova which produced the Gum nebula is now fossilized in the still live, though failing, H II region. The main body of the nebula suggests a hollow center or shell form, with a characteristic radius of about half the distance to the outlying fragments. The edges of the main body patches are typically sharp and often bright. The structure of the Gum nebula appears to be dependent on the event of ionization and possibly on the details of heating. It is not now an unstructured ambient medium, as it may have been before the recent ionization. Several hypotheses are presented for a structured ambient medium.
Task 1 of the NEW MOONS (NASA Evaluation With Models of Optimized Nuclear Spacecraft) study is discussed. Included is an introduction to considerations of launch vehicles, spacecraft, spacecraft subsystems, and scientific objectives associated with precursory unmanned missions to Jupiter and thence out of the ecliptic plane, as well as other missions to Jupiter and other outer planets. Necessity for nuclear power systems is indicated. Trajectories are developed using patched conic and n-body computer techniques.
The Apollo 15 metric camera photography provided a number of spectacular views of most of the southern and central portions of the unique systems of major lava flows that stretch diagonally across Mare Imbrium from the general area of Euler Crater to a point east of Le Verrier Crater. A preliminary examination of the photographs indicates that the source of the material comprising the major flows is situated to the west of Euler Crater and south of the limits of the photographic coverage. The photographs also show clearly that most, if not all, the mare ridges included were formed after the solidification of the flows. Few color boundaries exist in the area of metric photography where the illumination angle is low enough to show the fronts of some of the very thin flows. However, patches of redder material lying northeast of Mt. Lahire are found to be enclosed by low flow fronts, confirming the theory that the redder material represents an earlier filling of the Imbrium basin.
A series of photographs of sea surface whitecap conditions for wind speeds of 10 to 25 m/sec was obtained and analyzed for areal coverage of white water. The results are in good agreement with semiempirical calculations based on the wind speed and the development of the wave spectrum only when the contribution of thin foam streaks oriented in the direction of the wind is neglected. Since both the actively forming whitecaps and the thin foam streaks contribute significantly to the microwave emissivity of the sea surface, it is important that the foam streaks be included in the theory but differentiated from large white caps and foam patches. A simple relationship that accounts for the foam streaks based on the rate of energy transfer, the wind speed, and the wave spectrum is proposed. By means of empirically derived constant terms for the microwave signatures of white caps and foam streaks, this theory was adapted to the prediction of the increase in brightness temperature due to foam, with reasonable results to wind speeds of 20 m/sec.
Laboratory measurements show that the spectra of capillary waves grow with wind speed over six orders of magnitude. The scatter in the data can be partially understood and predicted from a combination of turbulence theory, radar theory, and the small sample theory of statistical inference. When these results are applied to a prediction of the sea return values to be obtained by S193 on Skylab, it can be shown that the size of the illuminated patch effectively averages out the horizontal scales of gustiness, so that the measurement will correspond to the synoptic scale wind.
Evaluation of combined photographic and photometric measurements made on the 1969 NASA airborne expedition, yielding a description of the midday oval, cusp region, and polar cap auroral precipitation at low magnetic activity (Kp = 0, 1+). The observations delineate three regions through the description of the type of aurora observed and the photometrically inferred change in energy of the particles: (1) the region in and equatorward of the oval where greater than 3-keV electrons are associated with 6300 A/4278 A ratios less than or equal to 1 and with a diffuse glow or structured arcs; (2) the cusp region where electrons of several hundred electron volts and spikes of more energetic electrons are associated with 6300 A/4278 A ratios between 10 and 35 in broken, fragmented, rayed features and patches; (3) the polar cap where discrete earth-sun-aligned arcs have height luminosity profiles in 5577 A, 6300 A (forbidden O I), and 4278 A (N2(+)) that suggest incoming electrons with an energy spectrum of 2-keV characteristic energy above a low-energy (few hundred electron volts) background.
An auroral substorm generates displays of pulsating auroras in ways which show a dependence upon both local time and latitude relative to the auroral oval. For several hours after midnight pulsating auroras can be observed in the wake of poleward expansions or within equatorward spreading diffuse envelopes of meridional extent of several hundred kilometers. As the dawn meridian is approached the displays of pulsating auroras tend increasingly to be comprised of distinct eastward drifting patches easily recorded by all-sky cameras.
All four large EUV bursts for which there were available concurrent white light observations of at least fair quality, were detected as white light flares. The rise times and maxima of the white light emissions coincided with rise times and maxima of the EUV bursts. The frequency of strong EUV bursts suggests that white light flares may occur at the rate of five or six per year near sunspot maximum. All of the white light flare areas coincided with intense bright areas of the H-alpha flares. These small areas appeared to be sources of high velocity ejecta in H-alpha. The white light flares occurred as several knots or patches of 2 to 15 arc-sec diameter, with bright cores perhaps less than 2 arc-sec diameter (1500 km). They preferred the outer penumbral borders of strong sunspots within 10 arc-sec of a longitudinal neutral line in the magnetic field.
The effect of varying some membrane parameters is explored, basing the investigation on computer simulation of the Hodgkin-Huxley equations for the squid giant axon, including variations in the membrane capacitance, conductances, and the rate constants. It is shown that by reducing the degree of regeneration in the excitable membrane, the character of the nerve signal can be smoothly changed from that of the axonal spike to essentially electrotonic spread, with all gradations in between. The reduction in the degree of regeneration can most simply be brought about by a decrease in the density of active membrane patches.
Computer program was devised to compute free-fall trajectories of satellites, allowing for injection errors and midcourse velocity perturbations. Program consists of trajectory perturbing program and N-body integrating conic program which can also be used as 2-body patch conic program.
Three personal hygiene cleansing agents and one laundry detergent (sodium dodecyl benzene sulfonate), which are all candidates for use on long-duration space missions, were evaluated in terms of dermatological effects on human subjects and effects on microbiological species. None of the four materials exhibited adverse dermatological effects from either skin patch tests of two weeks duration or a simulated Skylab personal hygiene regimen of up to four weeks duration. No significant alterations in skin microflora during the use regimen were found. None of the four materials were found to serve as microbiological support media for the species tested, but a species of air-borne mold was observed to grow rapidly in a neutralized aqueous solution. None of the candidate agents was found to be strongly biocidal.
Improved information on the morphology and distribution of the Cayley Formation, provided by Apollo 16 orbital photography, leads to a concept in which the Cayley Formation was deposited as fluidized debris that traveled beyond the presently recognizable extent of the Imbrium Basin ejecta. By this hypothesis, each basin-forming event produced thick plains deposits in a belt peripheral to the continuous ejecta blanket and may have deposited a thinner layer in pools over the entire moon. Thus, each patch of terra plains is likely to be underlain by a sequence of fluidized ejecta deposits, which were derived from most or all multi-ring basins younger than the occupied depression. If the light color of the plains results from a high feldspar content of the excavated crustal rocks, an explanation of the absence of exposed pre-Cayley mare rocks may be that they are buried or dusted over.
The author has identified the following significant results. The effects of a prescribed burn in the Sam Houston National Forest have been detected from ERTS-1 coverage of November 27, 1972. The burn was first identified on aircraft underflight photography of November 7, 1972. On color infrared aircraft photography it appeared as a green patch, indicating stressed vegetation, in an area of red coloration, indicating vigorous vegetation. It was later detected on the color composite of ERTS-1 bands 4, 5, and 7, as a black area in otherwise red vegetation. The fire, covering approximately 40 hectares (100 acres), was intentionally started to clear out heavy underbrush so that trees could be marked prior to harvesting. The significance of this observation is that a light burn of this type and its subsequent effects on vegetation could be detected on ERTS-1 imagery. Continued observation of this type of phenomenon under various conditions may provide a means of identifying such an occurrence without a prior knowledge of the event.
The author has identified the following significant results. A significant result was reported 13 July on anomalous dark patches observed in certain ERTS-1 images. This sunglint related feature is possible whenever the solar elevation is greater than 55 deg and the surface waters are calm. It is observed in all MSS bands. Although the bright specular point is nearly 300 nm from nadir no bright specular returns are possible with a 0930 local time descending path-only diffuse glitter, that may reach reflectance levels of 1-2% under wind speeds of 5-10 m/sec and solar elevations greater than 60 deg.
The author has identified the following significant results. Geomorphic features related to a known porphyry copper deposit at Saindak, western Chagai District, Pakistan, are easily distinguished on ERTS-1 images. No new prospecting sites were recognized on the basis of the images alone, but new information from the images was used in conjunction with known geology to evaluate two previously known speculative areas and to suggest one additional one. The study showed that Saindak-type deposits are less likely in some extensive areas of the Chagai District than formerly believed. The Saindak deposit is in an area of relatively soft folded sedimentary and volcanic rocks. The deposit is characterized by a linear zone of easily eroded sulfide-rich rock surrounded by a resistant rim of hornfels and propylitically altered rock. Both this rim and the central sulfide-rich valley are conspicuous features on the images. Swarms of dikes are probably useful for distinguishing real rims from other resistant rock types, but there is no expression of them on the image, although they are easily seen on aerial photographs of the Saindak rim. During field mapping, patches of strong red and yellow hue related to the mineral natrojarosite were noted in the central valley. Attempts to detect a color anomaly using simple false color composites were not successful.
TIDY, a computer code which edits and renumerates FORTRAN decks which have become difficult to read because of many patches and revisions, is described. The old program is reorganized so that statement numbers are added sequentially, and extraneous FORTRAN statements are deleted. General instructions for using TIDY on the IBM 360/67 Tymeshare System, and specific instructions for use on the NASA/AMES IBM 360/67 TSS system are included as well as specific instructions on how to run TIDY in conversational and in batch modes. TIDY may be adopted for use on other computers.
The possible association of an X-ray source with the galaxy IC 3576 was investigated in a program of optical observations of this galaxy. The observations show that patches and condensations belonging to the galaxy are distributed in a nonrandom, spiral fashion. This distinctive morphology corresponds to the dwarf spiral of the second type discussed by van den Bergh (1959). Radio observations are also considered, giving attention to a 21-cm emission due to neutral hydrogen in IC 3576. It is pointed out that the evidence at this time that the X-ray source in Virgo corresponds to IC 3576 is positional only.