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NASA NTRS1994

Molecular Hydrogen and Excitation in the HH 1-2 System

We present a series of molecular hydrogen images of the Herbig-Haro 1-2 system in the 1-0 S(1) transition at 2.121 microns, with a spatial resolution of ~2 inches. The distribution of H 2 is then compared with that of the excitation, given by the [S II] 6717+6731 to H-alpha line ratio. We find that most optical condensations in the HH 1-2 system, including the VLA 1 jet, have H 2 counterparts. H 2 emission is detected in most low excitation knots, as expected for low velocity shocks (50 km s sup-1 <), but also in high excitation regions, like in HH 1F and HH 2A'.

molecular↗

NASA NTRS1994

Molecular hydrogen and excitation in the HH 1-2 system

We present a series of molecular hydrogen images of the Herbig-Haro 1-2 system in the 1-0 S(1) transition at 2.121 microns, with a spatial resolution of approximately 2 sec. The distribution of H2 is then compared with that of the excitation, given by the (S II) 6717+6731 to H-alpha line ratio. We find that most optical condensations in the HH 1-2 system, including the VLA 1 jet, have H2 counterparts. H2 emission is detected in most low excitation knots, as expected for low velocity shocks (50 km/s less than), but also in high excitation regions, like in HH 1F and HH 2A min. For these latter objects, the H2 emission could be due to the interaction of the preionizing flux, produced by 150-200 km/s shocks, with the surrounding interstellar matter, i.e., fluorescence. The lack fluorescent lines in the ultraviolet (UV), however, suggest a different mechanism. H2 is detected at the tip of the VLA 1 jet, where the knot morphology suggests the presence of a second bow shock. H2 is detected also SE of HH 2E and SW of HH 1F, in regions with known NH3 emission.

Noriega-Crespo, A.↗

NASA NTRS1993

The embedded young stars in the Taurus-Auriga molecular cloud. II - Models for scattered light images

We describe NIR imaging observations of embedded young stars in the Taurus-Auriga molecular cloud. We find a large range in J-K and H-K colors for these class I sources. The bluest objects have colors similar to the reddest T Tauri stars in the cloud; redder objects lie slightly above the reddening line for standard ISM dust and have apparent K extinctions of up to 5 mag. Most of these sources also show extended NIR emission on scales of 10-20 arcsec which corresponds to linear sizes of 1500-3000 AU. The NIR colors and nebular morphologies for this sample and the magnitude of linear polarization in several sources suggest scattered light produces most of the NIR emission in these objects. We present modeling results that suggest mass infall rates that agree with predictions for cold clouds and are generally consistent with rates estimated from radiative equilibrium models. For reasonable dust grain parameters, the range of colors and extinctions require flattened density distributions with polar cavities evacuated by bipolar outflows. These results support the idea that infall and outflow occur simultaneously in deeply embedded bipolar outflow sources. The data also indicate fairly large centrifugal radii and large inclinations to the rotational axis for a typical source.

Kenyon, Scott J.↗

NASA NTRS2009

Zinc Alloys for the Fabrication of Semiconductor Devices

ZnBeO and ZnCdSeO alloys have been disclosed as materials for the improvement in performance, function, and capability of semiconductor devices. The alloys can be used alone or in combination to form active photonic layers that can emit over a range of wavelength values. Materials with both larger and smaller band gaps would allow for the fabrication of semiconductor heterostructures that have increased function in the ultraviolet (UV) region of the spectrum. ZnO is a wide band-gap material possessing good radiation-resistance properties. It is desirable to modify the energy band gap of ZnO to smaller values than that for ZnO and to larger values than that for ZnO for use in semiconductor devices. A material with band gap energy larger than that of ZnO would allow for the emission at shorter wavelengths for LED (light emitting diode) and LD (laser diode) devices, while a material with band gap energy smaller than that of ZnO would allow for emission at longer wavelengths for LED and LD devices. The amount of Be in the ZnBeO alloy system can be varied to increase the energy bandgap of ZnO to values larger than that of ZnO. The amount of Cd and Se in the ZnCdSeO alloy system can be varied to decrease the energy band gap of ZnO to values smaller than that of ZnO. Each alloy formed can be undoped or can be p-type doped using selected dopant elements, or can be n-type doped using selected dopant elements. The layers and structures formed with both the ZnBeO and ZnCdSeO semiconductor alloys - including undoped, p-type-doped, and n-type-doped types - can be used for fabricating photonic and electronic semiconductor devices for use in photonic and electronic applications. These devices can be used in LEDs, LDs, FETs (field effect transistors), PN junctions, PIN junctions, Schottky barrier diodes, UV detectors and transmitters, and transistors and transparent transistors. They also can be used in applications for lightemitting display, backlighting for displays, UV and visible transmitters and detectors, high-frequency radar, biomedical imaging, chemical compound identification, molecular identification and structure, gas sensors, imaging systems, and for the fundamental studies of atoms, molecules, gases, vapors, and solids.

Ryu, Yungryel↗

NASA NTRS2005

Electronic Transport through Self Assembled Thiol Molecules: Effect of Monolayer Order, Dynamics and Temperature

We present the charge transport and tunneling conductance of self assembled organic thiol molecules and discuss the influence of order and dynamics in the monolayer on the transport behavior and the effect of temperature. Conjugated thiol molecular wires and organometals such as terpyridine metal complexes provide a new platform for molecular electronic devices and we study their self assembly on Au(111) substrates by the scanning tunneling microscope. Determining the organization of the molecule and the ability to control the nature of its interface with the substrate is important for reliable performance of the molecular electronic devices. By concurrent scanning tunneling microscopy and spectroscopy studies on SAMs formed from oligo (phenelyne ethynelyne) monolayers with and without molecular order, we show that packing and order determine the response of a self assembled monolayer (SAM) to competing interactions. Molecular resolution STM imaging in vacuum shows that the OPES adopt an imcommensurate SAM structure on Au(111) with a rectangular unit cell. Tunneling spectroscopic measurements were performed on the SAM as a function of junction resistance. STS results show that the I-Vs are non linear and asymmetric due to the inherent asymmetry in the molecular structure, with larger currents at negative sample biases. The asymmetry increases with increasing junction resistance due to the asymmetry in the coupling to the leads. This is brought out clearly in the differential conductance, which also shows a gap at the Fermi level. We also studied the effect of order and dynamics in the monolayer on the charge transport and found that competing forces between the electric field, intermolecular interactions, tip-molecule physisorption and substrate-molecule chemisorption impact the transport measurements and its reliability and that the presence of molecular order is very important for reproducible transport measurements. Thus while developing new electronic platforms based on molecules, it is important to have a good control of the molecule-substrate interface, for the devices to perform reliably. While such a control would minimize fluctuations and dynamics in the ensemble, the real challenge is to develop device architectures that are tolerant to fluctuations, since they cannot be totally eliminated in these low dimensional soft systems. Results of temperature dependent STS measurements will also be discussed.

Dholakia, Geetha↗

NASA NTRS1995

Shocked Molecular Hydrogen in Herbig-Haro Objects and Jets

We present near-IR array images of the shocked molecular hydrogen in Herbig-Haro objects and jets from YSOs. These observations, in combination with optical and EEL observations of atomic emission, serve as probes of the shock conditions within the objects.

Schultz, A.S.B.↗

NASA NTRS1997

Molecular Shocks Associated with Massive Young Stars: CO Line Images with a New Far-Infrared Spectroscopic Camera on the Kuiper Airborne Observatory

Under the terms of our contract with NASA Ames Research Center, the University of Rochester (UR) offers the following final technical report on grant NAG 2-958, Molecular shocks associated with massive young stars: CO line images with a new far-infrared spectroscopic camera, given for implementation of the UR Far-Infrared Spectroscopic Camera (FISC) on the Kuiper Airborne Observatory (KAO), and use of this camera for observations of star-formation regions 1. Two KAO flights in FY 1995, the final year of KAO operations, were awarded to this program, conditional upon a technical readiness confirmation which was given in January 1995. The funding period covered in this report is 1 October 1994 - 30 September 1996. The project was supported with $30,000, and no funds remained at the conclusion of the project.

Watson, Dan M.↗

NASA NTRS1993

An experimental investigation of mixing enhancement in a simulated scramjet combustor by use of swirling jets

It is desired to maintain supersonic flow through the combustor of supersonic airbreathing engines to reduce static temperatures and total pressure losses inherent in reducing flow to subsonic speeds. Due to the supersonic speeds through the combustor, mixing of the fuel and air must by rapid for complete combustion to occur within a reasonable streamwise distance. It was proposed that the addition of swirl to the fuel jet prior to injection might enhance the mixing of the fuel with the air. The effects of swirl on the mixing of a 30 deg wall jet into a Mach 2 flow were experimentally investigated. Swirl was introduced into the fuel stream by tangential injection into a cylindrical swirl chamber. The flow was then accelerated through a convergent-divergent nozzle with an area ratio of two, and supersonically injected into the Mach 2 flow such that the static pressure of the fuel matched the effective back pressure of the main flow. Two different cases with swirl and one without swirl were investigated, with both helium and air simulating the fuel. Rayleigh scattering was used to visualize the flow and seeding the fuel with water allowed it to be traced through the main flow. Using histograms of the pure molecular Rayleigh scattering images, the helium concentration in the jet-mixing region of the flow was monitored and found to decrease slightly with swirl, indicating better mixing. Thresholding the water-seeded images allowed the jet-mixing region to be isolated and showed a slight increase in this area with swirl. Penetration, however, was slightly less with swirl. Rescaling the data for equal mass flow rates allowed comparison for a scramjet application of a combustor with a single injector and the desire to fuel to a specified fuel-to-oxidant ratio. These results showed a substantial increase in the spreading area with swirl, an increase in the mixing occurring in this area, and slightly better penetration.

Kraus, Donna Karen↗

NASA NTRS2001

Diffusivity Measurements Made Instant and Easy

A compact common path interferometer (CPI) system has been developed to measure the diffusivity of liquid pairs. The CPI is an optical technique that can be used to measure changes in the gradient of the refraction index of transparent materials. It uses a shearing interferometer that shares the same optical path from a laser light source to the final imaging plane. The molecular diffusion coefficient of liquids can be determined from the physical relations between changes in the optical path length and liquid phase properties. When the data obtained by using the CPI have been compared with similar results from other techniques, the instrument has been demonstrated to be far superior to other instruments for measuring the diffusivity of miscible liquids while staying very compact and robust (ref. 1). Because of its compactness and ease of use, the CPI has been adopted for use in studies of interface dynamics as well as other diffusion-controlled process applications (ref. 2). This progress will permit experiments in microgravity that can quantitatively answer basic science questions about mass and thermal diffusion and their effect in transport processes. This instrument is a spinoff of a diagnostic development for microgravity fluid physics experiments at the NASA Glenn Research Center that has used optics and electronics existing in the fluid physics laboratory for feasibility studies. Optical diagnostic techniques have become an integral part of many areas of measurement applications in industrial and research laboratories. Many types of interferometers and their phase-shifted versions have been used as instruments for measuring optical wave fronts for lens testing and combustion and fluid flow diagnostics. One of these, the point diffraction interferometer, is considered to be robust (see, for example, ref. 3) because it has a common-path design. The point diffraction interferometer is difficult to align and has a limited measurement range for liquid-phase applications. Interferometry and schlieren techniques have been widely used for many years for gas-flow-visualization. On the other hand, the CPI, which is basically a Wollaston prism Polarizer in combination with an analyser (crystalline quartz retardation plate) is used instead of a point diffraction interferometer unit. The advantage of using the CPI over other optical techniques is that it can make quantitative measurements in liquids with the large index of refraction variations that often occur in interface dynamics studies. This can be simply accomplished by using different prism polarizers for each particular experimental condition.

Rashidnia, Nasser↗

NASA NTRS2004

Antigenic Protein In Microgravity-Grown Human Mixed Mullerian Tumor (LN1) Cells Preserved In RNA Stabilizing Agent

Cells treated with RNAlater(TradeMark) have previously been shown to contain antigenic proteins that can be visualized using Western blot analysis. These proteins seem to be stable for several months when stored in RNA stabilizer at 4 C. Antigenic protein can be recovered from cells that have been processed using an Ambion RNAqueous(Registered TradeMark) kit to remove RNA. In this set of experiments, human mixed Mullerian tumor (LNI) cells grown on the International Space Station during Expedition 3 were examined for antigenic stability after removal of RNA. The cells were stored for three months in RNAlater(TradeMark) and RNA was extracted. The RNA filtrate containing the protein was precipitated, washed, and suspended in buffer containing sodium dodecyl sulfate (SDS). Samples containing equal concentrations of protein were loaded onto SDS-polyacrylamide gels. Proteins were separated by electrophoresis and transferred by Western blot to polyvinylidene fluoride (PVDF) membrane. The Western blots were stained with an enhanced chemiluminescent ECL(Registered Trademark) Plus detection kit (Amersham) and scanned using a Storm 840 gel image analyzer (Amersham, Molecular Dynamics). ImageQuant(Registered TradeMark) software was used to quantify the densities of the protein bands. The ground control and flight LN1 cell samples showed a similar staining pattern over time with antibodies to vimentin, glyceraldehyde-3-phosphate dehydrogenase, and epithelial membrane antigens.

Hammond, Dianne K.↗

NASA NTRS2004

Antigenic Protein In Microgravity-Grown Human Mixed Mullerian Tumor (LN1) Cells Preserved In RNA Stabilizing Agent

Cells treated with RNAlater(TradeMark) have previously been shown to contain antigenic proteins that can be visualized using Western blot analysis. These proteins seem to be stable for several months when stored in RNA stabilizer at 4 C. Antigenic protein can be recovered from cells that have been processed using an Ambion RNAqueous(Registered TradeMark) kit to remove RNA. In this set of experiments, human mixed Mullerian tumor (LN1) cells grown on the International Space Station during Expedition 3 were examined for antigenic stability after removal of RNA. The cells were stored for three months in RNAlater(TradeMark) and RNA was extracted. The RNA filtrate Containing the protein was precipitated, washed, and suspended in buffer containing sodium dodecyl sulfate (SDS). Samples containing equal concentrations of protein were loaded onto SDS-polyacrylamide gels. Proteins were separated by electrophoresis and transferred by Western blot to polyvinylidene fluoride (PVDF) membrane. The Western blots were stained with an enhanced chemiluminescent ECL(Registered TradeMark)Plus detection kit (Amersham) and scanned using a Storm 840 gel image analyzer (Amersham, Molecular Dynamics). ImageQuant(Registered TradeMark)a software was used to quantify the densities of the protein bands. The ground control and flight LN1 cell samples showed a similar staining pattern over time with antibodies to vimentin, glyceraldehyde-3-phosphate dehydrogenase, and epithelial membrane antigens.

Hammond, Dianne K.↗

NASA NTRS2000

He 2-113: A multipolar planetary nebula with rings around a cool wolf-rayet star

We present Her imaging and molecular-line (CO) observations of He 2-113, an object which belongs to a rare class of planetary nebulae with Wolf-Rayet type central stars.

Bipolar protoplanetary nebula circumstellar matter↗

NASA NTRSDate not supplied

Open Science for Life in Space: Data Sharing and Tools for Knowledge Discovery

The next era in human space exploration is rapidly approaching and will require the use of countermeasures to deep space health hazards. The development of countermeasures (or, the re-purposing of existing agents) will be highly dependent on our understanding of basic biological responses to space stressors (e.g. ionizing radiation, altered gravitational fields, altered day-night cycles, confinement, isolation, hostile-closed environments, distance-duration from Earth, exposure to celestial regolith, etc.). The fast-growing array of space biological data, which in the past was simply archived after minimal analysis, holds great potential if it can be reorganized and formatted for Open Science. Organizing the data for such analysis is a challenge because of its diverse nature (molecular, cellular, tissue, imaging, whole organism and behavior). We will discuss here several strategies that NASA’s Biological and Physical Science Division has put in place to maximize the return on investment for spaceflight bioscience data. Open Science, as a scientific philosophy, is the concept that the more people who have access to the data, the more knowledge will be gained from it. This guiding principle led NASA to develop GeneLab in 2015. GeneLab houses spaceflight and relevant ground-based multi-omics data, and has grown to ~400 transcriptomic, proteomic, metabolomic and epigenomic datasets from plant, rodent, small animal, and microbial space experiments. GeneLab provides users with various tools for data analysis and a visualization portal that allows users to interact with gene expression data from space-related ‘omics experiments. Open Science is also about building scientific communities, and with this spirit in mind, GeneLab has spawned several Analysis Working Groups (AWGs), comprised of more than 200 volunteer scientists. The AWGs initially provided feedback on the processing pipeline and metadata ‘omics standards for GeneLab. Over the last few years, they have become a community-driven science enterprise, engaging in large meta-analysis of GeneLab datasets, resulting in 10 publications (beyond the originally submitted research). Overall, the Open Science nature of GeneLab has resulted in a high degree of data re-use, resulting in 38 additional publications derived from the original 67 publication over the past four years. The enormous success and knowledge gained from GeneLab has led to a collection of sister NASA “Open Science Data Repositories (OSDR)” and research support groups. These include the NASA Ames Life Sciences Data Archive (ALSDA), the NASA Biological Institutional Scientific Collection (NBISC), and the Biospecimen Sharing Program (BSP). All are adopting the GeneLab data architecture system to maximize open-access, find-ability, accessibility, interoperability, and reusability (FAIR). ALSDA collects and curates phenotypic-physiological bioimaging-behavioral data from space and space-relevant non-human experiments, oftentimes coming from the same omics-associated experimental datasets found in GeneLab. Since 2021, a community of ~100 researchers have rallied around ALSDA, to provide feedback in a new ALSDA AWG focused on phenotypic-physiological investigation-sample-assay metadata standards (e.g., Micro-Computed Tomography, Light/Fluorescence Microscopy, Western Blot, Flow Cytometry, Novel Object Recognition, Elevated Plus Maze, etc. of ~50 assays collected). These standards are part of a new single point-of-entry data submission portal for all non-human Space Biology and Human Research Program principal investigators, to submit, curate, and share their research data. With open-access space biological data now collected and curated together with rich metadata, and with the potential for linkage to “big data” from the international biological and medical communities (NIH, EBI, etc.), the artificial intelligence and machine learning (AI/ML) era has started for Space Biology. Several other talks will cover these topics in this conference.

life sciences↗

NASA NTRSDate not supplied

Open Science for Life in Space: Data Sharing and Tools for Knowledge Discovery

The next era in human space exploration is rapidly approaching and will require the use of countermeasures to deep space health hazards. The development of countermeasures (or, there-purposing of existing agents) will be highly dependent on our understanding of basic biological responses to space stressors (e.g. ionizing radiation, altered gravitational fields, altered day-night cycles, confinement, isolation, hostile-closed environments, distance-duration from Earth, exposure to celestial regolith, etc.). The fast-growing array of space biological data, which in the past was simply archived after minimal analysis, holds great potential if it can be reorganized and formatted for Open Science. Organizing the data for such analysis is a challenge because of its diverse nature (molecular, cellular, tissue, imaging, whole organism and behavior). We will discuss here several strategies that NASA's Biological and Physical Science Division has put in place to maximize the return on investment for spaceflight bioscience data. Open Science, as a scientific philosophy, is the concept that the more people who have access to the data, the more knowledge will be gained from it. This guiding principle led NASA to develop GeneLab in 2015. GeneLab houses spaceflight and relevant ground-based multi-omics data, and has grown to ~400 transcriptomatic, proteomic, metabolomic and epigenomic datasets from plant, rodent, small animal, and microbial space experiments. GeneLab provides users with various tools for data analysis and a visualization portal that allows users to interact with gene expression data from space-related 'omics experiments. Open Science is also about building scientific communities, and with this spirit in mind, GeneLab has spawned several Analysis Working Groups (AWGs), comprised of more than 200 volunteer scientists. The AWGs initially provided feedback on the processing pipeline and metadata 'omics standards for GeneLab. Over the last few years, they have become a community-driven science enterprise, engaging in large meta-analysis of GeneLab datasets, resulting in 10 publications (beyond the originally submitted research). Overall, the Open Science nature of GeneLab has resulted in a high degree of data-use, resulting in 40 enabled publications by open data. The enormous success and knowledge gained from GeneLab has led to a collection of sister NASA "Open Science Data Repositories (OSDR)" and research support groups. These include the NASA Ames Life Sciences Data Archive (ALSDA), the NASA Biological Institutional Scientific Collection (NBISC), and the Biospecimen Sharing Program (BSP). All are adopting the GeneLab data architecture system to maximize open-access, find-ability, accessibility, interoperability, and reusability (FAIR). ALSDA collects and curates phenotypic-physiological bioimaging-behavioral data from space and space-relevant non-human experiments, oftentimes coming from the same omics-associated experimental datasets found in GeneLab. Since 2021, a community of ~100 researchers have rallied around ALSDA, to provide feedback in a new ALSDA AWG focused on phenotypic-physiological investigation-sample-assay metadata standards (e.g., Micro-Computed Tomography, Light/Flourescence Microscopy, Western Blot, Flow Cytometry, Novel Object Recognition, Elevated Plus Maze, etc. of ~50 assays collected). These standards are part of a new single point-of-entry data submission portal for all non-human Space Biology and Human Research Program principal investigators, to submit, curate, and share their research data. With open-access space biological data now collected and curated together with rich metadata, and with the potential for linkage to "big data" from the international biological and medical communities (NIH, EBI, etc.), the artificial intelligence and machine learning (AI/ML) era has started for Space Biology.

omics↗

NASA NTRSDate not supplied

NASA Open Science Data Repository: Maximizing Spaceflight Bioscience Data

space biology↗

NASA NTRS2010

Kinetic Temperatures of the Dense Gas Clumps in the Orion KL Molecular Core

High angular-resolution images of the J = 18(sub K)-17(sub K) emission of CH3CN in the Orion KL molecular core were observed with the Submillimeter Array (SMA). Our high-resolution observations clearly reveal that CH3CN emission originates mainly from the Orion Hot Core and the Compact Ridge, both within approximately 15 inches of the warm and dense part of Orion KL. The clumpy nature of the molecular gas in Orion KL can also be readily seen from our high-resolution SMA images. In addition, a semi-open cavity-like kinematic structure is evident at the location between the Hot Core and the Compact Ridge. We performed excitation analysis with the "population diagram" method toward the Hot Core, IRc7, and the northern part of the Compact Ridge. Our results disclose a non-uniform temperature structure on small scales in Orion KL, with a range of temperatures from 190-620 K in the Hot Core. Near the Compact Ridge, the temperatures are found to be 170-280 K. Comparable CH3CN fractional abundances of 10(exp -8) to 10(exp -7) are found around both in the Hot Core and the Compact Ridge. Such high abundances require that a hot gas phase chemistry, probably involving ammonia released from grain mantles, plays an important role in forming these CH3CN molecules.

Wang, Kuo-Song↗

NASA NTRS1997

A Highly Collimated Molecular Hydrogen Jet in IRAS 05487+0255: NIR Imaging and Spectroscopy

Explore the source record for details and available documents.

bipolar jets IRAS 05487+0255 Herbig-Haro outflow↗

NASA NTRS1986

An optical imaging and polarimetric study of the Lynds 723 and Barnard 335 molecular outflow regions

Optical polarization measurements are reported for a sample of stars viewed through the periphery of two dense molecular clouds, Barnard 335 and Lynds 723. These observations suggest that the direction of the magnetic field threading these clouds lies along position angle 111 + or - 4 deg for B335 and 90 + or - 8 deg for L723. In each case, the deduced field direction is approximately parallel to the direction defined by a collimated bipolar molecular outflow driven by a highly obscured FIR source. R, I, and H-alpha CCD images of these regions reveal knots of optical emission apparently associated with the molecular outflows. In the case of L723, two emission features are found within the blueshifted wing of the molecular outflow; along with the FIR source, these knots define a position angle nearly identical to that of the molecular flow. For B335, the observed emission knot lies in the redshifted wing of the molecular outflow along a position angle approximately equal to that of the flow.

Vrba, F. J.↗