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AbstractAbstract
[en] The number concentration and density of 1 micron and submicron sized grains in interplanetary space, as well as their relation to the larger zodical dust particles, and the importance of the beta meteoroid phenomenon are currently being questioned. The best approach to collecting large numbers of intact micron and submicron sized cosmic dust particles in real time while avoiding terrestrial and man made contamination would be to employ a tethered subsatellite from a space station down into the earth's atmosphere. Such a subsatellite tied to the space shuttle by a 100 km long tether is being developed. It is also possible that a permanent space station would allow the use of a tether even longer than 100 km. It should be noted that the same tethered collectors could also be employed to study the composition and flux of man made earth orbiting debris in any direction within 100 km or so of the space station
Primary Subject
Source
Greeley, R.; Williams, R.J.; Chicago Univ., IL (USA); p. 2; Nov 1987; p. 2; Experiments in planetary and related sciences and the space station; Tempe, AZ (USA); 15 Sep 1986; Available from NTIS, PC A09/MF A01
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AbstractAbstract
[en] The number concentration and density of 1 micron and submicron sized grains in interplanetary space, as well as their relation to the larger zodical dust particles, and the importance of the Beta meteoroid phenomenon are currently being questioned. The best approach to collecting large numbers of intact micron and submicron sized cosmic dust particles in real time while avoiding terrestrial and man made contamination would be to employ a tethered subsatellite from a space station down into the Earth's atmosphere. Such a subsatellite tied to the space shuttle by a 100 km long tether is being developed. It is also possible that a permanent space station would allow the use of a tether even longer that 100 km. It should be noted that the same tethered collectors could also be employed to study the composition and flux of man made Earth orbiting debris in any direction within 100 km or so of the space station
Primary Subject
Source
Greeley, R.; Williams, R.J.; National Aeronautics and Space Administration, Houston, TX (USA). Lyndon B. Johnson Space Center; vp; May 1986; vp; Space station planetology experiments (SSPEX); Flagstaff, AZ (USA); 20 Jun 1985; Available from NTIS, PC A05/MF A01
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Corso, G.J. Jr.
Northwestern Univ., Chicago, Ill. (USA)1975
Northwestern Univ., Chicago, Ill. (USA)1975
AbstractAbstract
[en] A comprehensive study of the 54 known Wolf--Rayet stars of M33 is undertaken with the intention of improving our knowledge of the Wolf--Rayet phenomenon, identifying significant features of their distribution in an Sc galaxy, and discerning possible trends in the variation of chemical composition of the interstellar medium from place to place within that galaxy. Thirty-seven of these stars were classified for the first time into carbon and nitrogen sequences on the basis of photographic photometry of image tube plates obtained with the Kitt Peak 84-inch telescope and an ITT magnetically focused image tube equipped with a set of narrow-band interference filters designed to isolate the broad emission features between 4640 A and 4686 A due to N III, C III-IV, and He II. The subclasses WC6-9, missing in the Large Magellanic Cloud, were found in M33, although there is a tendency for the known stars of both sequences to belong to the high-excitation subclasses. The distribution of these stars was compared with the distributions of luminous blue stars, dust, and H II regions. Star counts on the image tube plates indicated that one out of every 75 stars in M33 brighter than M/sub B/ = --4.5 is a Wolf--Rayet star
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1975; 97 p; University Microfilms Order No. 76-11,879.; Thesis (Ph. D.).
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Report
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Thesis/Dissertation
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AbstractAbstract
No abstract available
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Journal Article
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Astrophysical Journal; v. 172(3); p. 577-582
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AbstractAbstract
[en] The quantitative local quasar model proposed by Bell and Fort has been subjected to a critical analysis. Their quasar model requires a large number for sudden increases in the intrinsic luminosity of quasars, occurring in exactly 0.165 magnitude jumps. Such a requirement has no known physical basis. The standard error in the intrinsic redshift component z/subx/ being more than 0.05, no significance can be attached to the feature in the power spectrum of z/subx/ with a 0.1 periodicity. This conclusion has been tested by performing power spectrum analyses on samples with perfect periodicity
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Journal Article
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Astrophysical Journal; v. 204(2); p. 337-340
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Del Corso, G.J.; Martin, J.W.; Strobel, D.L.
Carpenter Technology Corp., Reading, PA1990
Carpenter Technology Corp., Reading, PA1990
AbstractAbstract
[en] This patent describes a workable, boron-containing, stainless steel alloy, an article formed therefrom, and a process for manufacturing same. The as-worked alloy in accordance with the invention is characterized by having a boride particle areal density per weight percent boron (AN) defined by a relationship given
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Source
2 Jan 1990; 6 Jun 1988; 12 p; US PATENT DOCUMENT 4891080/A/; U.S. Commissioner of Patents, Washington, D.C. 20231, USA, $1.50; ?: 6 Jun 1988
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Patent
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AbstractAbstract
[en] Optical photometry in blue light of selected bright quasars, Lacertids, active galaxies, and X-ray sources with a 1-m f/15 Cassegrain reflector is reported. The observed magnitude and amplitude for 3C 273, 3C 351, 3C 454.3, 3C 66A, PKS 2141 + 17, BL Lac, OJ287, and Zw0039.5 + 004 are described. The techniques used to collect and reduce the data are discussed. Tables of observed blue magnitudes for the data are provided. 18 references
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Journal Article
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Publications of the Astronomical Society of the Pacific; ISSN 0004-6280; ; CODEN PASPA; v. 98 p. 1287-1290
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Squyres, S.; Corso, G.J.; Griffiths, L.D.; Mackinnon, I.D.R.; Marshall, J.R.; Nuth, J.A. III; Werner, B.; Wolfe, J.
Experiments in Planetary and Related Sciences and the Space Station1987
Experiments in Planetary and Related Sciences and the Space Station1987
AbstractAbstract
[en] A wide variety of experiments can be conducted on the Space Station that involve the physics of small particles of planetary significance. Processes of interest include nucleation and condensation of particles from a gas, aggregation of small particles into larger ones, and low velocity collisions of particles. All of these processes could be investigated with a general purpose facility on the Space Station. The microgravity environment would be necessary to perform many experiments, as they generally require that particles be suspended for periods substantially longer than are practical at 1 g. Only experiments relevant to planetary processes will be discussed in detail here, but it is important to stress that a particle facility will be useful to a wide variety of scientific disciplines, and can be used to address many scientific problems
Primary Subject
Source
Greeley, R.; Williams, R.J.; National Aeronautics and Space Administration, Houston, TX (USA). Lyndon B. Johnson Space Center; p. 4; Nov 1987; p. 4; Experiments in planetary and related sciences and the space station; Tempe, AZ (USA); 15 Sep 1986; Available from NTIS, PC A09/MF A01
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AbstractAbstract
[en] It has been suggested that the low-red shift quasar 1928 + 738 be utilized in the establishment of an extragalactic reference frame. We have observed the quasar in blue light during an interval of 137 days and found it essentially constant, varying by no more than about I 0.15 magnitude from its average value. Slowly varying long-term changes are not ruled out and others are encouraged to monitor this source in the future. (author)
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Numerical Data
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AbstractAbstract
[en] Alloys of Fe49Co49V2 (Hiperco Alloy 50) (Hiperco is a registered trademark of CRS Holdings, Inc.), both annealed and thermally aged, were studied using anomalous synchrotron x-ray and neutron powder diffraction. Rietveld and diffraction profile analysis indicated both an increase in the structural order parameter and a small lattice expansion (∼0.0004 A) after aging at 450 degree C for 200 h. In addition, a cubic minority phase (<0.3%) was identified in the open-quote open-quote annealed close-quote close-quote sample, which increased noticeably (0.3%→0.8%) as a result of aging. The presence of antiphase domain boundaries in the alloys was also revealed. These results directly correlate with the observed changes in the magnetization behavior and challenge the notion that a open-quote open-quote fully close-quote close-quote ordered Fe endash Co alloy demonstrates optimum soft magnetic properties. copyright 1996 American Institute of Physics
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