232
232
Jul 25, 2010
07/10
by
Toon, Owen B.; Turco, Richard; Jordan, Josep
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A one dimensional model of cloud microphysics was used to simulate the formation and evolution of polar stratospheric ice clouds. Some of the processes which are included in the model are outlined. It is found that the clouds must undergo preferential nucleation upon the existing aerosols just as do tropospheric cirrus clouds. Therefore, there is an energy barrier between stratospheric nitric acid particles and ice particles implying that nitric acid does not form a continuous set of solutions...
Topics: ALL SKY PHOTOGRAPHY, CATALOGS, INFRARED ASTRONOMY SATELLITE, STARS, COSMOLOGY, GALAXIES,...
314
314
May 29, 2011
05/11
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Garrison, James L.; Ruffini, Giulio; Rius, Antonio; Cardellach, Estelle; Masters, Dallas; Armathys, Michael; Zavorotny, Valer
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An experiment to collect bistatically scattered GPS signals from a balloon at 37 km altitude has been conducted. This experiment represented the highest altitude to date that such signals were successfully recorded. The flight took place in August 1999 over the Mediterranean sea, between a launch in Sicily and recovery near Nerpio, a town in the Sierra de Segura, Albacete province of Huelva, Spain. Results from this experiment are presented, showing the waveform shape as compared to theoretical...
Topics: BACKGROUND RADIATION, GALACTIC HALOS, INTERSTELLAR MATTER, SHADOWS, INFRARED ASTRONOMY SATELLITE,...
529
529
May 22, 2011
05/11
by
Hirsch, David; Johnson, Harr
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eye 529
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The NASA Lewis Research Center requested NASA Johnson Space Center White Sands Test Facility to conduct flammability, odor, offgassing, thermal vacuum stability, and compatibility tests with aerospace fluids of several wire insulations.
Topics: ASTRONOMICAL CATALOGS, FAR INFRARED RADIATION, INFRARED ASTRONOMY, INFRARED ASTRONOMY SATELLITE,...
207
207
May 31, 2011
05/11
by
Hamaker, Joseph W
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Current space project cost models attempt to predict space flight project cost via regression equations, which relate the cost of projects to technical performance metrics (e.g. weight, thrust, power, pointing accuracy, etc.). This paper examines the introduction of engineering management parameters to the set of explanatory variables. A number of specific engineering management variables are considered and exploratory regression analysis is performed to determine if there is statistical...
Topics: BACKGROUND RADIATION, X RAYS, SKY SURVEYS (ASTRONOMY), AUTOCORRELATION, POINT SOURCES, INFRARED...
482
482
May 31, 2011
05/11
by
Landis, Geoffrey A
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A major objective for NASA exploration of Mars is to determine whether life has existed on Mars in the past, and whether such life on Mars may persist to the present day. On Earth, life exists in all niches in which water exists in liquid form for at least a portion of the year. On Mars, any liquid water would have to be a highly concentrated brine solution. It is likely, therefore, that any present-day Martian microorganisms would be similar to terrestrial halophiles.
Topics: MILKY WAY GALAXY, HALOS, EMISSION, VARIATIONS, INFRARED ASTRONOMY, INFRARED ASTRONOMY SATELLITE,...
201
201
May 28, 2011
05/11
by
Pines, D
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eye 201
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Two Flight Model AMSU-A Phase Locked Oscillators (PIN 1348360-1, S/N F07 and F08) have been tested per AES Test Procedure AE-26758 Rev. B, which include full functional testing, vibration testing, thermal testing, and AM/FM Noise testing. Both assemblies satisfactorily passed all performance requirements of the AE-26633 Product Specification. During the thermal cycling of both units, spurs developed 1 MHz from the carrier when the units were cold, and TARs were written to document the anomaly....
Topics: INFRARED SOURCES (ASTRONOMY), INFRARED RADIATION, COSMIC DUST, GRAINS, COMPUTERIZED SIMULATION,...
329
329
May 22, 2011
05/11
by
Han, Daesoo; Kim, Young S.; Noz, Marilyn E
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eye 329
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It is shown that the system of two coupled harmonic oscillators shares the basic symmetry properties with the covariant harmonic oscillator formalism which provides a concise description of the basic features of relativistic hadronic features observed in high-energy laboratories. It is shown also that the coupled oscillator system has the SL(4,r) symmetry in classical mechanics, while the present formulation of quantum mechanics can accommodate only the Sp(4,r) portion of the SL(4,r) symmetry....
Topics: EMBEDDING, PROTOSTARS, INFRARED ASTRONOMY SATELLITE, MASS, MOLECULAR CLOUDS, STAR CLUSTERS, STAR...
265
265
Jul 21, 2010
07/10
by
Wdowiak, T. J.; Kubinec, W. R.; Nuth, J. A
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eye 265
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It is proposed to carry out slitless spectroscopy at ultraviolet wavelengths from orbit of meteoric debris associated with comets. The Eta Aquarid and Orionid/Halley and the Perseid/1962 862 Swift-Tuttle showers would be principal targets. Low light level, ultraviolet video technique will be used during night side of the orbit in a wide field, earthward viewing mode. Data will be stored in compact video cassette recorders. The experiment may be configured as a GAS package or in the HITCHHIKER...
Topics: DUST, MAGNESIUM, GAS ANALYSIS, INFRARED ASTRONOMY SATELLITE, IUE, M STARS, BALMER SERIES, CALCIUM,...
3,498
3.5K
May 21, 2011
05/11
by
NON
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Pocket Statistics is published for the use of NASA managers and their staff. Included herein is Administrative and Organizational information, summaries of Space Flight Activity including the NASA Major Launch Record, and NASA Procurement, Financial, and Manpower data. The NASA Major Launch Record includes all launches of Scout class and larger vehicles. Vehicle and spacecraft development flights are also included in the Major Launch Record. Shuttle missions are counted as one launch and one...
Topics: A STARS, INFRARED RADIATION, MAIN SEQUENCE STARS, STELLAR EVOLUTION, STELLAR MASS, ASTRONOMY, DATA...
The Infrared Astronomical Satellite (IRAS) was launched January 26, 1983. During its 300-day mission, IRAS surveyed over 96 pct of the celestial sphere at four infrared wavelengths, centered approximately at 12, 25, 60, and 100 microns. This is Volume 3, The Point Source Catalog Declination Range 30 deg greater than delta greater than 0 deg.
Topics: NASA Technical Reports Server (NTRS), ALL SKY PHOTOGRAPHY, CATALOGS, INFRARED ASTRONOMY SATELLITE,...
197
197
May 31, 2011
05/11
by
Burner, A. W.; Liu, Tianshu; DeLoach, Richar
texts
eye 197
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The uncertainty of videogrammetric techniques used for the measurement of static aeroelastic wind tunnel model deformation and wind tunnel model pitch angle is discussed. Sensitivity analyses and geometrical considerations of uncertainty are augmented by analyses of experimental data in which videogrammetric angle measurements were taken simultaneously with precision servo accelerometers corrected for dynamics. An analysis of variance (ANOVA) to examine error dependence on angle of attack,...
Topics: INFRARED ASTRONOMY, ALGORITHMS, INFRARED ASTRONOMY SATELLITE, IMAGE PROCESSING, SKY SURVEYS...
466
466
May 29, 2011
05/11
by
Asbury, Scott C.; Yetter, Jeffrey A
texts
eye 466
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The NASA Langley Configuration Aerodynamics Branch has conducted an experimental investigation to study the static performance of innovative thrust reverser concepts applicable to high-bypass-ratio turbofan engines. Testing was conducted on a conventional separate-flow exhaust system configuration, a conventional cascade thrust reverser configuration, and six innovative thrust reverser configurations. The innovative thrust reverser configurations consisted of a cascade thrust reverser with...
Topics: ACTIVE GALACTIC NUCLEI, SEYFERT GALAXIES, LINE SPECTRA, X RAY ASTRONOMY, SPACE OBSERVATIONS (FROM...
In an earlier paper, I recounted an exploratory analysis, using Gaussian windows, of a data set derived from the Infrared Astronomical Satellite. Here, my goals are to develop strategies for finding structural features in a data set in a many-dimensional space, and to find ways to describe the shape of such a data set. After a brief review of Gaussian windows, I describe the current implementation of the method. I give some ways of describing features that we might find in the data, such as...
Topics: NASA Technical Reports Server (NTRS), INFRARED ASTRONOMY SATELLITE, MULTIVARIATE STATISTICAL...
The Infrared Astronomical Satellite (IRAS) was launched 26 January 1983. During its 300-day mission, it surveyed over 96 pct of the celestial sphere at four infrared wavelengths, centered approximately at 12, 25, 60, and 100 microns. This is Volume 4, The Point Source Catalog Declination Range 0 deg greater than delta greater than -30 deg.
Topics: NASA Technical Reports Server (NTRS), ALL SKY PHOTOGRAPHY, CATALOGS, COSMOLOGY, INFRARED ASTRONOMY...
284
284
May 23, 2011
05/11
by
Motter, Mark A
texts
eye 284
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A predictive, multiple model control strategy is developed based on an ensemble of local linear models of the nonlinear system dynamics for a transonic wind tunnel. The local linear models are estimated directly from the weights of a Self Organizing Feature Map (SOFM). Local linear modeling of nonlinear autonomous systems with the SOFM is extended to a control framework where the modeled system is nonautonomous, driven by an exogenous input. This extension to a control framework is based on the...
Topics: CALIBRATING, CONTINUOUS SPECTRA, INFRARED RADIATION, PRODUCT DEVELOPMENT, STELLAR SPECTRA,...
The Infrared Astronomical Satellite (IRAS) was launched January 26, 1983. During its 300-day mission, IRAS surveyed 96 pct of the celestial sphere at four infrared wavelengths, centered approximately at 12, 25, 60, and 100 microns. This is Volume 2, The Point Source Catalog Declination Range 90 deg greater than delta greater than 30 deg.
Topics: NASA Technical Reports Server (NTRS), ALL SKY PHOTOGRAPHY, CATALOGS, INFRARED ASTRONOMY SATELLITE,...
An investigation into the extended distribution of far-infrared (FIR) emission associated with nearby Seyfert galaxies is made using a set of MEM reconstructions of IRAS Chopped Photometric Channel (CPC) data (Marston 1993). The data is compared to a set of HII/starburst galaxy images similarly processed in order to compare distributions and FIR color properties. It is shown that the central 1 kpc or so of Seyfert galaxies show extended FIR emission. FIR colors suggest that the bulk of this...
Topics: NASA Technical Reports Server (NTRS), INFRARED ASTRONOMY SATELLITE, SEYFERT GALAXIES, STAR...
The Infrared Astronomical Satellite (IRAS) was launched January 26, 1983. During its 300-day mission, IRAS surveyed over 96 pct of the celestial sphere at four infrared wavelengths, centered approximately at 12, 25, 60, and 100 microns. This is Volume 5, The Point Source Catalog Declination Range -30 deg greater than delta greater than -50 deg.
Topics: NASA Technical Reports Server (NTRS), ALL SKY PHOTOGRAPHY, CATALOGS, INFRARED ASTRONOMY SATELLITE,...
131
131
May 23, 2011
05/11
by
Reid, Max B
texts
eye 131
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Experimental results of the optical calculation of potential-field maps suitable for mobile robot navigation are presented and described. The optical computation employs two write modes of a microchannel spatial light modulator. In one mode, written patterns expand spatially, and this characteristic is used to create an extended two-dimensional function representing the influence of the goal in a robot's workspace. Distinct obstacle patterns are written in a second, nonexpanding, mode. A model...
Topics: STELLAR SPECTRA, M STARS, INFRARED SPECTRA, CONTINUOUS SPECTRA, ASTRONOMICAL PHOTOMETRY, KUIPER...
227
227
May 23, 2011
05/11
by
Waite, J. Hunter, Jr
texts
eye 227
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The purpose of this grant was to study the ultraviolet and X-ray emissions associated with the impact of comet Shoemaker-Levy 9 with Jupiter. The University of Michigan task was primarily focused on theoretical calculations. The NAGW-4788 subtask was to be largely devoted to determining the constraints placed by the X-ray observations on the physical mechanisms responsible for the generation of the X-rays. Author summarized below the ROSAT observations and suggest a physical mechanism that can...
Topics: KUIPER AIRBORNE OBSERVATORY, SPECTROMETERS, SATELLITE OBSERVATION, SPECTRAL EMISSION, STELLAR...
In this period the first maps were made during two flights of the Kuipper Airborne Observatory (KAO) in January 1986. One of these shows extended emission at 100 and 160 microns from the dense core B35 containing the IRAS point source 05417+0907. The 160 micron emission has approximately the same extent as the NH3 (1,1) line emission at 1.4 cm, indicating close correspondence between the warm dust and the dense gas. The 160 micron map shows a previously unknown secondary maximum about 90 arcsec...
Topics: NASA Technical Reports Server (NTRS), DUST, GASES, INFRARED ASTRONOMY, MAPPING, C-141 AIRCRAFT,...
The spiking and memory behavior of a number of Ge:Ga detectors was studied. The detectors were manufactured at a number of locations using several different contacting techniques. Two detectors manufactured for the IRAS program by Rockwell International were studied more extensively than the others. These detectors IRD 1981 and IRD 1982 were 'witness sample' detectors for the IRAS bands 4 and 3, respectively. During the testing period both the apparatus and the test procedures were changed...
Topics: NASA Technical Reports Server (NTRS), GALLIUM, INFRARED DETECTORS, PERFORMANCE TESTS, INFRARED...
The Infrared Astronomical Satellite (IRAS) was launched January 26, 1983. During its 300-day mission, it surveyed over 96 pct of the celestial sphere at four infrared wavelengths, centered approximately at 12, 25, 60, and 100 microns. This is Volume 6, The Point Source Catalog Declination Range -50 deg greater than delta greater than -90 deg.
Topics: NASA Technical Reports Server (NTRS), ALL SKY PHOTOGRAPHY, CATALOGS, DECLINATION, INFRARED...
A typical pointed observation in the Infrared Astronomical Satellite (IRAS) was designed to fit into a 15 minute window. Observing constraints, however, did not always permit targets from the scientific program to be observed on exactly 15 minute centers and a few months into the mission it was realized that the automatic scheduling program left times when no observations were being made. In order to use this potentially wasted observing time, a mode of pointed observations, the 'filler' mode,...
Topics: NASA Technical Reports Server (NTRS), FAINT OBJECTS, GALAXIES, INFRARED ASTRONOMY SATELLITE,...
The joint effort is reported of scientists and engineers from the Netherlands, the United Kingdom, and the United States working as a team for the purpose of exploring the possibility of a cooperative venture. The proposed mission builds upon experience gained from the successful Astronomical Netherlands Satellite (ANS). This satellite will be in a polar orbit at an altitude of 900 km. It will carry an 0.6 m diameter telescope cooled with helium to a temperature near 10K. An array of...
Topics: NASA Technical Reports Server (NTRS), ASTRONOMICAL SPECTROSCOPY, INFRARED ASTRONOMY SATELLITE,...
The environments of galaxies may affect both the presence and nature of the activity in their nuclei. We have undertaken a study of the environments of Seyfert and non-Seyfert Markarian galaxies to investigate the relationship between nuclear activity and external influences on the nucleus (MacKenty 1989; MacKenty, McLean, and Simpson 1990). Previous studies of the environments of Seyfert galaxies suggest a connection between the nature of the activity in the nuclear regions of the galaxy and...
Topics: NASA Technical Reports Server (NTRS), INFRARED ASTRONOMY SATELLITE, MARKARIAN GALAXIES, SEYFERT...
One of the most important discoveries of the Infrared Astronomical Satellite (IRAS) has been the detection of about 20,000 galaxies with 60 microns fluxes above 0.5 Jy. From the observational point of view, the IRAS galaxies are ideal tracers of density, since they are homogeneously detected over most of the sky, and their fluxes are unaffected by galactic extinction. The nearby universe was mapped by the IRAS galaxies to a distance of approximately 200 h(exp -1) Mpc for the absolute value of b...
Topics: NASA Technical Reports Server (NTRS), DENSITY (NUMBER/VOLUME), GALAXIES, INFRARED ASTRONOMY...
We have been obtained high-resolution data (20 in at 50 microns and 30 in at 100 microns) on the KAO using Paul Harvey's 2 x 10 element photometer in both scanning and nodding modes. The practical flux limit for scanning is about 100 Jy. For fainter sources, a nodding (beam-switching) mode, which spends more time on the source is used. This technique has been used successfully on objects as faint as 10 Jy; the 1 sigma noise for a 1 hour integration is about 1 Jy. Although not as sensitive as...
Topics: NASA Technical Reports Server (NTRS), HIGH RESOLUTION, INFRARED ASTRONOMY SATELLITE,...
The objective of this proposal was to measure variations in the 1/4 keV emission from the galactic halo, using ROSAT (x-ray astronomy satellite) Position Sensitive Proportional Counters (PSPC) observations toward known enhancements in the absorbing column density along the line-of-sight out of the Galaxy. Target directions were selected to have a low total hydrogen column density but to also show significant gradients in the amount of absorbing material, as traced by Infrared Astronomical...
Topics: NASA Technical Reports Server (NTRS), MILKY WAY GALAXY, HALOS, EMISSION, VARIATIONS, INFRARED...
The result of two searches for infrared counterparts of Gamma-ray Bursters (GRB's) is reported. The first search was made using data from the Infrared Astronomy Satellite and covered 23 positions. The second search was made with the Kitt Peak 1.5 m telescope and covered 3 positions. In neither of these two searches was any infrared candidate detected.
Topics: NASA Technical Reports Server (NTRS), DETECTION, GAMMA RAY BURSTS, INFRARED RADIATION, RADIATION...
The influence of coefficients for the three axes of the Infrared Astronomical Satellite (IRAS) were established to determine the maximum allowable thrust difference between the two vent nozzles of the aperture cover tank low thrust vent system and their maximum misalignment. Test data generated by flow and torque measurements permitted the selection of two nozzles whose thrust differential was within the limit of the attitude control capability. Based on thrust stand data, a thrust vector...
Topics: NASA Technical Reports Server (NTRS), ALIGNMENT, INFLUENCE COEFFICIENT, INFRARED ASTRONOMY...
210
210
May 26, 2011
05/11
by
Kikta, Dianne C.; Barney, Christopher C.; Threatte, Rose M.; Fregly, Melvin J.; Rowland, Neil E.; Greenleaf, John E
texts
eye 210
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Subcutaneous administration of 1-5-hydroxytryptophan (5-HTP), the precursor of serotonin, to female rats induces copious drinking accompanied by activation of the renin-angiotensin system. Neither a reduction in blood pressure nor body temperature accompanied administration of 5-HTP. The objective of the present study was to determine whether serotonin-induced dipsogenesis, like that of 5-HTP, is mediated via the renin-angiotensin system. Serotonin (2 mg/kg, SC)-induced drinking was inhibited...
Topics: EXAMINATION, INFRARED ASTRONOMY SATELLITE, HIGH RESOLUTION, FAR INFRARED RADIATION, DYNAMIC RANGE,...
We have used the Deep Survey telescope of the Extreme Ultraviolet Explorer to investigate shadows in the diffuse EUV/soft X-ray background that are cast by clouds in the interstellar medium. We confirm the existence of a shadow previously reported and provide evidence for two new shadows. We used IRAS data to identify the clouds producing these shadows and to determine their optical depth to EUV radiation. The EUV-absorbing clouds are optically thick in the EUV, and all EUV emission detected in...
Topics: NASA Technical Reports Server (NTRS), INTERSTELLAR MATTER, BACKGROUND RADIATION, EXTREME...
171
171
May 21, 2011
05/11
by
Ewell, Robert N
texts
eye 171
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The U.S. Space Foundation displayed its prototype Space Technology Hall of Fame exhibit design at the Technology 2003 conference in Anaheim, CA, December 7-9, 1993. In order to sample public opinion on space technology in general and the exhibit in particular, a computer-based survey was set up as a part of the display. The data collected was analyzed.
Topics: MAIN SEQUENCE STARS, STAR FORMATION, PRE-MAIN SEQUENCE STARS, STELLAR ENVELOPES, STELLAR EVOLUTION,...
In order to isolate the diffuse extragalactic component of the soft X-ray background, we have used a combination of ROSAT All-Sky Survey and IRAS 100 micron data to separate the soft X-ray background into five components. We find a Local Hot Bubble similar to that described by Snowden et al (1998). We make a first calculation of the contribution by unresolved Galactic stars to the diffuse background. We constrain the normalization of the Extragalactic Power Law (the contribution of the...
Topics: NASA Technical Reports Server (NTRS), BACKGROUND RADIATION, X RAYS, SKY SURVEYS (ASTRONOMY),...
The project was designed to explore new morphological filtering, techniques for the removal of foreground Galactic 'Cirrus' emission from NASA Infrared Astronomical Satellite (IRAS) data, especially at 100 microns, using parallel processors as the main engine for achieving this result. The ultimate aim was to provide NASA with completely filtered data by the end of the grant period for the entire IRAS 100 and possibly 60 micron database. If successful, the filtered data would reveal many new...
Topics: NASA Technical Reports Server (NTRS), MORPHOLOGY, INFRARED IMAGERY, EMISSION SPECTRA, INFRARED...
Measurements of the far-infrared bidirectional reflectance distribution functions (BRDF) of four samples of Martin Black coating and one sample of gold coated aluminum from the telescope to be flown on the Infrared Astronomy Satellite (IRAS) are presented. At incidence angles near 35 deg Martin Black is a diffuse reflector at wavelengths as long as 36 microns. The gold coated aluminum sample from the IRAS sunshield has a visible grain which causes a strong diffraction enhancement of the BRDF at...
Topics: NASA Technical Reports Server (NTRS), FAR INFRARED RADIATION, INFRARED ASTRONOMY SATELLITE,...
The Final Technical Report covering the period from 15 Aug. 1989 to 14 Aug. 1991 is presented. Areas of research included Infrared Astronomy Satellite (IRAS) high resolution studies and modeling of closely interacting galaxies; galaxy collisions: infrared observations and analysis of numerical models; and UV spectroscopy of massive young stellar populations in interacting galaxies. Both observational studies and theoretical modelling of interacting galaxies are covered. As a consequence the...
Topics: NASA Technical Reports Server (NTRS), COLLISIONS, INFRARED ASTRONOMY, INTERACTING GALAXIES,...
In this program, we used the IRAS database to identify and study proto-planetary nebulae (PPNs), objects in transition from the asymptotic giant branch (AGB) to the planetary nebula (PN) phase. Such objects radiate predominately in the mid-infrared 10-30 micrometer region, due to emission from warm (150-300 K) circumstellar dust. We used the IRAS database to identify 55 objects whose fluxes peak in the IRAS 25 micrometer band and which are associated with visible stars. We combined IRAS and...
Topics: NASA Technical Reports Server (NTRS), PLANETARY NEBULAE, INFRARED ASTRONOMY SATELLITE, DUST,...
I have examined all Infrared Astronomical Satellite (IRAS) data relevant to the 173 Galactic Wolf-Rayet (W-R) stars in an updated catalog, including the 13 stars newly discovered by Shara and coworkers. Using the W-R coordinates in these lists, I have examined the IRAS Point Source Catalog (PSC), the Faint Source Catalog, and the Faint Source Reject Catalog, and have generated one-dimensional spatial profiles ('ADDSCANs') and two-dimensional full-resolution images ('FRESCOs'). The goal was to...
Topics: NASA Technical Reports Server (NTRS), WOLF-RAYET STARS, LATE STARS, SKY SURVEYS (ASTRONOMY),...
More than 700 luminous stars in the infrared astronomical satellite (IRAS) Skyflux plates were examined for the presence of dust heated by a nearby star. This dust may be distinguished from the ubiquitous cool cirrus by its higher temperature and thus enhanced 60 micron emission. More than 120 dust clouds were found around only 106 of the stars with a volume filling factor of 0.006 and an intercloud separation of 46 pc. A region of dust smoothly distributed through the volume of space heated by...
Topics: NASA Technical Reports Server (NTRS), COSMIC DUST, INTERSTELLAR GAS, REFLECTION NEBULAE, SCALE...
The Large Deployable Reflector (LDR) is a telescope designed to carry out high-angular resolution, high-sensitivity observations at far-infrared and submillimeter wavelengths. The scientific rationale for the LDR is discussed in light of the recent Infrared Astronomical Satellite (IRAS) and Kuiper Airborne Observatory (KAO) results and the several new ground-based observatories planned for the late 1980s. The importance of high sensitivity and high angular resolution observations from space in...
Topics: NASA Technical Reports Server (NTRS), INFRARED ASTRONOMY, INFRARED TELESCOPES, LARGE DEPLOYABLE...
The icy-conglomerate model of comet nuclei has dominated all others since its introduction. It provided a basis for understanding the non-gravitational motions of comets which had perplexed dynamicists up to that time, and provided a focus for understanding cometary composition and origin. The image of comets as dirty snowballs was quickly adopted. Comet nuclei including their trail mass loss rates and refractory to volatile mass ratios are described.
Topics: NASA Technical Reports Server (NTRS), COMET NUCLEI, INFRARED ASTRONOMY SATELLITE, MASS RATIOS,...
The ways in which recent infrared observations, particularly by the Infrared Astronomy Satellite (IRAS), have influenced ideas about star formation in normal galaxies, are discussed.
Topics: NASA Technical Reports Server (NTRS), GALACTIC STRUCTURE, LUMINOSITY, RADIO ASTRONOMY, SPIRAL...
IRAS l6253-2429. the source of the Wasp-Waist Nebula seen in Spitzer IRAC images, is an isolated very low luminosity ("VeLLO") Class 0 protostar in the nearby rho Ophiuchi cloud. We present VLA ammonia mapping observations of the dense gas envelope feeding the central core accreting system. We find a flattened envelope perpendicular to the outflow axis, and gas cavities that appear to cradle the outflow lobes as though carved out by the flow and associated (apparently precessing) jet....
Topics: NASA Technical Reports Server (NTRS), AMMONIA, INFRARED ASTRONOMY SATELLITE, MASS, OPHIUCHI CLOUDS,...
The data analysis performed was to support the Orbital Verification (OV) and Science Verification (SV) of the GHRS was in the areas of the Digicon detector's performance and stability, wavelength calibration, and geomagnetic induced image motion. The results of the analyses are briefly described. Detailed results are given in the form of attachments. Specialized software was developed for the analyses. Calibration files were formatted according to the specifications in a Space Telescope Science...
Topics: NASA Technical Reports Server (NTRS), ALGORITHMS, GEOMAGNETISM, HUBBLE SPACE TELESCOPE, IMAGE...
Work is currently in progress to obtain temperature distributions of dust in the most infrared-luminous galaxies. The results presented are of a preliminary nature, representing a zeroth-order approximation. The objects which have been analyzed so far are all galaxies from the Infrared Astronomy Satellite (IRAS) Bright Galaxy Sample with infrared luminosities L sub IR greater than or equal to 10(exp 11) solar luminosity. They are: Arp 220, Mrk 231, Mrk 273, NGC 1614, NGC 3690, NGC 6285/6, and...
Topics: NASA Technical Reports Server (NTRS), COSMIC DUST, GALAXIES, INFRARED ASTRONOMY SATELLITE, INFRARED...
Twenty-one leak specimens were fabricated in the ends of stainless steel and aluminum tubes. Eighteen of these tubes were coated with a copolymer material to seal the leak. The other three specimens were left uncoated and served as control specimens. All 21 tubes were cold shocked in liquid helium 50 times and then the leak rate was measured while the tubes were submerged in superfluid helium at 1.7 K. During the cold shocks two of the coated specimens were mechanically damaged and eliminated...
Topics: NASA Technical Reports Server (NTRS), COATING, COPOLYMERS, CRYOGENICS, LEAKAGE, LIQUID HELIUM,...
Five hundred and fifty six stars in the IRAS PSC-2 that are suitable for stellar radiometric standards and are brighter than 1 Jy at 25 microns were identified. In addition, 123 stars that meet all of our criteria for calibration standards, but which lack a luminosity class were identified. An approach to absolute stellar calibration of broadband infrared filters based upon new models of Vega and Sirius due to Kurucz (1992) is presented. A general technique used to assemble continuous wide-band...
Topics: NASA Technical Reports Server (NTRS), CALIBRATING, INFRARED ASTRONOMY, INFRARED SPECTRA, STELLAR...
An extensive survey of 240 galaxies for hydroxyl absorption has been completed using the Arecibo Observatory. These galaxies were used to compile a sample to test for statistical correlations between the optical depth of the 1667 MHz hydroxyl line and various parameters of the parent galaxy. To be included in the sample, the radio flux density of the galaxy at 1667 MHz had to be between 20 mjy and 1000 mjy and the galactic declination between 0 and 38 deg. Since this sample contains mainly...
Topics: NASA Technical Reports Server (NTRS), ABUNDANCE, DISTORTION, GALACTIC STRUCTURE, HYDROXYL RADICALS,...
