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The measurement or reduction of stars in southern zones is reported. The catalog for the -35 deg to -40 deg zone is rapidly nearing completion. All the reductions and comparisons with other catalogs have been completed. The tables and star charts are being prepared in final form for publication.
A comparison of the spatial distribution of the 47 identified QSOs in the 3C and 3CR catalogs with the small-redshift galaxies contained in the Reference Catalog of Bright Galaxies shows that four QSOs with redshift in the range 0.5-1.4 are much closer to bright galaxies than would be expected if the 47 QSOs were distributed randomly. An extensive analysis of the distributions shows that the probability that this is a chance occurrence is less than 0.005. It is also shows that the radio-quiet QSO PHL 1226 lies very close to IC 1746 to which it appears to have a physical connection.
Spectroscopic observations and redshifts of 20 radio galaxies obtained with the Lick 120-inch telescope are presented. Ten of the radio galaxies are from the 3C R catalog, and the remainder are from the 4C, 5C, Ohio, and Parkes catalogs. The reported results represent a continuation of Burbidge's (1970) previously published data.
Evaluation of evidence pertaining to apparent associations between galaxies and quasi-stellar objects. It is shown that for the five 3C QSOs which lie very close to bright galaxies the QSO-galaxy angular separations are inversely proportional to the redshifts of the galaxies. This lends additional support to the association hypothesis. However, an analysis of an essentially disjoint sample of QSOs identified from the Parkes radio catalog, and fainter galaxies in the catalog of Zwicky and his associates, reveals no statistically significant tendency toward pairing of QSOs and galaxies. The results can be explained in one of two ways. One is that, despite the evidence to the contrary, the 3C results are due to chance. The other is that real associations in the second sample are masked by selection effects. It is shown that several selectional biases do indeed discriminate against the detection of QSO-galaxy pairs, especially for fainter objects. Finally, on the assumption that the 3C QSO-galaxy associations are real, the relationship of QSOs to galaxies is discussed.
The primary aim of this investigation was verification of basic methods which are to be used in cataloging elastomer dynamic properties (stiffness and damping) in terms of viscoelastic model constants. These constants may then be used to predict dynamic properties for general elastomer shapes and operating conditions, thereby permitting optimum application of elastomers as energy absorption and/or energy storage devices in the control of vibrations in a broad variety of applications. The efforts reported involved: (1) literature search; (2) the design, fabrication and use of a test rig for obtaining elastomer dynamic test data over a wide range of frequencies, amplitudes, and preloads; and (3) the reduction of the test data, by means of a selected three-element elastomer model and specialized curve fitting techniques, to material properties. Material constants thus obtained have been used to calculate stiffness and damping for comparison with measured test data. These comparisons are excellent for a number of test conditions and only fair to poor for others. The results confirm the validity of the basic approach of the overall program and the mechanics of the cataloging procedure, and at the same time suggest areas in which refinements should be made.
This publication represents a relisting of the Skylab-2, PTD Handheld Photography Catalog. The purpose of this publication is to provide imagery researchers a supplement to the PTD Catalog by alphabetically sorting together all similar major and minor features. Some cross-referencing of feature names was accomplished where the authors deemed necessary; however, no attempt was made to exhaust all possible means of cross-referencing. An example of the cross-referencing which was done: Kuril Islands may be found under the major feature column and also as a minor feature of Islands.
An analysis was made of ATS-1 data to determine at what point in the magnetic storm recovery phase are oscillations most likely to begin. The catalog of hourly values of equatorial Dst was used to determine the time of main phase decrease, and a catalog of oscillations from January to May 1968 to determine onset time as observed by ATS-1. For each oscillation event at ATS-1, the nearest prior main phase decrease with a magnitude of at least -35 gamma was determined, and the time difference between the onset of the event at ATS-1 and the time of main phase decrease was measured. The resulting data indicate that the most probable time to observe onset of transverse oscillations is within 24 hours after the main phase decrease.
This manual details the input instructions to the data bank, and explanation of the program and its output. The data bank was developed in satisfaction of two of the study tasks, the equipment thermal requirement catalog and the equipment characteristics and constraints catalog. The data bank contains 109 components within space tug avionics system. Other systems were not included in the data bank due to the available information, however, with some program modification, other systems could be incorporated into the data bank program. The data bank was developed and checked out and is compatible with the Univac 1108, and the CDC 6500 operating systems. The data contained in the data bank is general in content with emphasis on the component thermal design. The data is applicable to any spacecraft program where the components contained in the data bank can be applied in satisfaction of the system and subsystem requirements.
The Space Tug Thermal Control Study contained two tasks associated with the cataloging of equipment thermal requirements, physical characteristics and constraints. In satisfaction of these tasks a Data Bank program was developed to provide a means of standardizing the method of cataloging while using the computer to handle the data and format the data into the desired catalogues. During the course of the study 109 components were catalogued and included in the Data Bank. A standardized method was selected for describing each component. Each subsystem of the Avionics System is described on a subsystem header page which describes the types of components included within the subsystem, the quantity requirements, target weights, target power and relative comments. The individual components listed within each subsystem are not necessarily a complete list of candidate items but do represent several of the presently available components for consideration in a Tug application.
Effort was made to include as much engineering information on each component as possible, consistent with usefulness and catalog size limitations. The contents of this catalog contain components which were qualified for use with spacecraft monopropellant hydrazine and inert gas attitude control systems. Thrust ranges up to 44.5 N (10.0 lbf) for hydrazine and inert gas sytems were considered. Additionally, some components qualified for uses other than spacecraft attitude control are included because they are suitable for use in attitude controls systems.
Objectives were to conduct observations with the first satellite entirely devoted to X-ray astronomy and to analyze the results obtained. A catalog of X-ray sources was generated, and results of discoveries and further detailed observations of sources were presented in scientific journals and meetings. A list of how objectives were met, a brief description of the instrument, significant results, the X-ray catalog, and a complete bibliography of results are included.
An examination is conducted of the nine weaker sources in the list of Kellogg et al. (1973) which are well enough observed to be listed in the 3U catalog compiled by Giacconi et al. (1974). The cluster sizes are presented in a table and chi-square plots versus derived core radius and background counting rate are shown in a graph. X-ray luminosities calculated from the 3U catalog counting rates are presented as a function of X-ray size.
Appendices for the Timeline Analysis Program (TLA-1) were given. The appendices contain the Atlanta terminal area scenarios, the task catalog and the control and display configurations for the forward and aft flight decks of the NASA 515 aircraft, and the event/procedure, phase, mission, and subsystem catalogs.
Background information was given on the Nimbus 6 spacecraft and experiments as a basis for selecting, obtaining, and utilizing Nimbus 6 data in research studies. The basic spacecraft system operation and the objectives of the Nimbus 6 flight are outlined, followed by a detailed discussion of each of the experiments. The format, archiving, and access to the data are also described. Finally, the contents and format of the Nimbus 6 data catalogs are described. These catalogs will be issued periodically after the launch of Nimbus 6. They will contain representative pictorial data and daily temperature, humidity, infrared and radiometer data obtained during each period, as well as information on the collection and availability of all Nimbus 6 data.
A quantitative measure of the degree of concentration of a sample of galaxies toward any great circle is described and applied to the Shapley-Ames and de Vaucouleurs catalogs of bright galaxies as well as to computer-simulated catalogs of galaxies. It is found that the observed distribution can be explained as the combined result of obscuration by our Galaxy, purely local clustering on angular scales of less than about 10 deg, and our proximity to a rather large and populous cluster, the Virgo cluster. In order for this interpretation to be correct, the Virgo cluster must have a mean angular radius of the order of or greater than 15 deg. This interpretation is supported by recent measurements which do not indicate any large inhomogeneities in the motions of nearby galaxy clusters and which show that the mean recessional velocity of the Virgo cluster is consistent with a uniform Hubble expansion. If the present interpretation is correct, it may be possible to determine the Hubble constant directly from measurements of individual distance indicators (such as H II regions and the brightest stars) with distance moduli less than about 32.
A catalog of 1929 stars showing H-alpha emission on photographic plates is presented which covers the entire southern sky south of declination -25 deg to a red limiting magnitude of about 11.0. The catalog provides previous designations of known emission-line stars equatorial (1900) and galactic coordinates, visual and photographic magnitudes, H-alpha emission parameters, spectral types, and notes on unusual spectral features. The objects listed include 16 M stars, 25 S stars, 37 carbon stars, 20 symbiotic stars, 40 confirmed or suspected T Tauri stars, 16 novae, 14 planetary nebulae, 11 P Cygni stars, 9 Bep stars, 87 confirmed or suspected Wolf-Rayet stars, and 26 'peculiar' stars. Two new T associations are discovered, one in Lupus and one in Chamaeleon. Objects with variations in continuum or H-alpha intensity are noted, and the distribution by spectral type is analyzed. It is found that the sky distribution of these emission-line stars shows significant concentrations in the region of the small Sagittarius cloud and in the Carina region.
The conceptual design of an automated satellite design data base system is presented. The satellite catalog in the system includes data for all earth orbital satellites funded to the hardware stage for launch between 1970 and 1980, and provides a concise compilation of satellite capabilities and design parameters. The cost of satellite subsystems and components will be added to the base. Data elements are listed and discussed. Sensor and science and applications opportunities catalogs will be included in the data system. Capabilities of the BASIS storage, retrieval, and analysis system are used in the system design.
Details for identifying the first 66 reference points of a selenodetic control network are presented. These reference points consist of craters having diameters larger than 8 km and which are therefore detectable on most plates used so far in lunar photogrammetric studies. The distribution of the adopted 211 reference points on Blagg-Mueller (1935) maps is given along with the Blagg-Mueller catalog number of each crater. The correspondence is indicated among the Blagg-Mueller number, the Lunar and Planetary Laboratory Catalog number, and the frame number of Lunar Orbiter IV photographs on which the craters have been studied.