Modern Gemini-Approach to Technology Development for Human Space Exploration
NASA Technical Reports Server (NTRS)
White, Harold
2010-01-01
In NASA's plan to put men on the moon, there were three sequential programs: Mercury, Gemini, and Apollo. The Gemini program was used to develop and integrate the technologies that would be necessary for the Apollo program to successfully put men on the moon. We would like to present an analogous modern approach that leverages legacy ISS hardware designs, and integrates developing new technologies into a flexible architecture This new architecture is scalable, sustainable, and can be used to establish human exploration infrastructure beyond low earth orbit and into deep space.
Photometric Calibrations of Gemini Images of NGC 6253
NASA Astrophysics Data System (ADS)
Pearce, Sean; Jeffery, Elizabeth
2017-01-01
We present preliminary results of our analysis of the metal-rich open cluster NGC 6253 using imaging data from GMOS on the Gemini-South Observatory. These data are part of a larger project to observe the effects of high metallicity on white dwarf cooling processes, especially the white dwarf cooling age, which have important implications on the processes of stellar evolution. To standardize the Gemini photometry, we have also secured imaging data of both the cluster and standard star fields using the 0.6-m SARA Observatory at CTIO. By analyzing and comparing the standard star fields of both the SARA data and the published Gemini zero-points of the standard star fields, we will calibrate the data obtained for the cluster. These calibrations are an important part of the project to obtain a standardized deep color-magnitude diagram to analyze the cluster. We present the process of verifying our standardization process. With a standardized CMD, we also present an analysis of the cluster's main sequence turn off age.
Gemini Planet Imager coronagraph testbed results
NASA Astrophysics Data System (ADS)
Sivaramakrishnan, Anand; Soummer, Rémi; Oppenheimer, Ben R.; Carr, G. Lawrence; Mey, Jacob L.; Brenner, Doug; Mandeville, Charles W.; Zimmerman, Neil; Macintosh, Bruce A.; Graham, James R.; Saddlemyer, Les; Bauman, Brian; Carlotti, Alexis; Pueyo, Laurent; Tuthill, Peter G.; Dorrer, Christophe; Roberts, Robin; Greenbaum, Alexandra
2010-07-01
The Gemini Planet Imager (GPI) is an extreme AO coronagraphic integral field unit YJHK spectrograph destined for first light on the 8m Gemini South telescope in 2011. GPI fields a 1500 channel AO system feeding an apodized pupil Lyot coronagraph, and a nIR non-common-path slow wavefront sensor. It targets detection and characterizion of relatively young (<2GYr), self luminous planets up to 10 million times as faint as their primary star. We present the coronagraph subsystem's in-lab performance, and describe the studies required to specify and fabricate the coronagraph. Coronagraphic pupil apodization is implemented with metallic half-tone screens on glass, and the focal plane occulters are deep reactive ion etched holes in optically polished silicon mirrors. Our JH testbed achieves H-band contrast below a million at separations above 5 resolution elements, without using an AO system. We present an overview of the coronagraphic masks and our testbed coronagraphic data. We also demonstrate the performance of an astrometric and photometric grid that enables coronagraphic astrometry relative to the primary star in every exposure, a proven technique that has yielded on-sky precision of the order of a milliarsecond.
La galaxia NGC 6876 y su sistema de cúmulos globulares
NASA Astrophysics Data System (ADS)
Ennis, A. I.; Bassino, L. P.; Caso, J. P.
2017-10-01
We present preliminary results of the deep photometric study of the elliptical galaxy NGC6876, located at the center of the Pavo group, and its globular cluster system. We use images obtained with the GMOS camera mounted on the Gemini South telescope, in the and bands, with the purpose of disentangling the evolutionary history of the galaxy on the basis of their characteristics.
Index maps for Gemini earth photography
NASA Technical Reports Server (NTRS)
Giddings, L. E.
1975-01-01
Index maps for the Gemini missions are presented; these are for the Gemini 3 through Gemini 12 missions. The maps are divided into four sections: the whole earth; the Western Hemisphere and eastern Pacific Ocean; Africa, India, and the Near East; and Asia, Australia, and the Pacific Ocean.
Gemini Program Mission Planning Report
NASA Technical Reports Server (NTRS)
1965-01-01
This report defines the Gemini Program objectives and presents guidelines for the individual Gemini missions. It provides general space vehicle configuration data, and descriptions of planned missions. Contingency mission requirements and extravehicular operations to be performed during specific missions are described in the last two sections of the basic document. Data on spacecraft weights and Gemini Launch Vehicle performance capabilities are provided in Appendix A, while Appendix B provides descriptions of onboard experiments to be conducted during Gemini missions.
Gemini Observations of Galaxies in Rich Early Environments (GOGREEN) I: survey description
NASA Astrophysics Data System (ADS)
Balogh, Michael L.; Gilbank, David G.; Muzzin, Adam; Rudnick, Gregory; Cooper, Michael C.; Lidman, Chris; Biviano, Andrea; Demarco, Ricardo; McGee, Sean L.; Nantais, Julie B.; Noble, Allison; Old, Lyndsay; Wilson, Gillian; Yee, Howard K. C.; Bellhouse, Callum; Cerulo, Pierluigi; Chan, Jeffrey; Pintos-Castro, Irene; Simpson, Rane; van der Burg, Remco F. J.; Zaritsky, Dennis; Ziparo, Felicia; Alonso, María Victoria; Bower, Richard G.; De Lucia, Gabriella; Finoguenov, Alexis; Lambas, Diego Garcia; Muriel, Hernan; Parker, Laura C.; Rettura, Alessandro; Valotto, Carlos; Wetzel, Andrew
2017-10-01
We describe a new Large Program in progress on the Gemini North and South telescopes: Gemini Observations of Galaxies in Rich Early Environments (GOGREEN). This is an imaging and deep spectroscopic survey of 21 galaxy systems at 1 < z < 1.5, selected to span a factor >10 in halo mass. The scientific objectives include measuring the role of environment in the evolution of low-mass galaxies, and measuring the dynamics and stellar contents of their host haloes. The targets are selected from the SpARCS, SPT, COSMOS, and SXDS surveys, to be the evolutionary counterparts of today's clusters and groups. The new red-sensitive Hamamatsu detectors on GMOS, coupled with the nod-and-shuffle sky subtraction, allow simultaneous wavelength coverage over λ ˜ 0.6-1.05 μm, and this enables a homogeneous and statistically complete redshift survey of galaxies of all types. The spectroscopic sample targets galaxies with AB magnitudes z΄ < 24.25 and [3.6] μm < 22.5, and is therefore statistically complete for stellar masses M* ≳ 1010.3 M⊙, for all galaxy types and over the entire redshift range. Deep, multiwavelength imaging has been acquired over larger fields for most systems, spanning u through K, in addition to deep IRAC imaging at 3.6 μm. The spectroscopy is ˜50 per cent complete as of semester 17A, and we anticipate a final sample of ˜500 new cluster members. Combined with existing spectroscopy on the brighter galaxies from GCLASS, SPT, and other sources, GOGREEN will be a large legacy cluster and field galaxy sample at this redshift that spectroscopically covers a wide range in stellar mass, halo mass, and clustercentric radius.
The ionization mechanism of NGC 185: how to fake a Seyfert galaxy?
NASA Astrophysics Data System (ADS)
Martins, L. P.; Lanfranchi, G.; Gonçalves, D. R.; Magrini, L.; Teodorescu, A. M.; Quireza, C.
2012-02-01
NGC 185 is a dwarf spheroidal satellite of the Andromeda galaxy. From mid-1990s onwards it was revealed that dwarf spheroidals often display a varied and in some cases complex star formation history. In an optical survey of bright nearby galaxies, NGC 185 was classified as a Seyfert galaxy based on its emission line ratios. However, although the emission lines in this object formally place it in the category of Seyferts, it is probable that this galaxy does not contain a genuine active nucleus. NGC 185 was not detected in radio surveys either in 6 or 20 cm, or X-ray observations, which means that the Seyfert-like line ratios may be produced by stellar processes. In this work, we try to identify the possible ionization mechanisms for this galaxy. We discussed the possibility of the line emissions being produced by planetary nebulae (PNe), using deep spectroscopy observations obtained with the Gemini Multi-Object Spectrograph - North (GMOS-N), at Gemini. Although the fluxes of the PNe are high enough to explain the integrated spectrum, the line ratios are very far from the values for the Seyfert classification. We then proposed that a mixture of supernova remnants and PNe could be the source of the ionization, and we show that a composition of these two objects do mimic Seyfert-like line ratios. We used chemical evolution models to predict the supernova rates and to support the idea that these supernova remnants should be present in the galaxy. Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership.
The Initial-Final Mass Relationship: Spectroscopy of White Dwarfs in NGC 2099 (M37)
NASA Astrophysics Data System (ADS)
Kalirai, Jasonjot Singh; Richer, Harvey B.; Reitzel, David; Hansen, Brad M. S.; Rich, R. Michael; Fahlman, Gregory G.; Gibson, Brad K.; von Hippel, Ted
2005-01-01
We present new observations of very faint white dwarfs (WDs) in the rich open star cluster NGC 2099 (M37). Following deep, wide-field imaging of the cluster using the Canada-France-Hawaii Telescope, we have now obtained spectroscopic observations of candidate WDs using both the Gemini Multi-Object Spectrograph on Gemini North and the Low-Resolution Imaging Spectrometer on Keck. Of our 24 WD candidates (all fainter than V=22.4), 21 are spectroscopically confirmed to be bona fide WDs, four or five of which are most likely field objects. Fitting 18 of the 21 WD spectra with model atmospheres, we find that most WDs in this cluster are quite massive (0.7-0.9 Msolar), as expected given the cluster's young age (650 Myr) and, hence, high turnoff mass (~2.4 Msolar). We determine a new initial-final mass relationship and almost double the number of existing data points from previous studies. The results indicate that stars with initial masses between 2.8 and 3.4 Msolar lose 70%-75% of their mass through stellar evolution. For the first time, we find some evidence of a metallicity dependence on the initial-final mass relationship. Based on observations with Gemini (run ID GN-2002B-Q-11) and Keck. Gemini is an international partnership managed by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the National Science Foundation. The W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and NASA, was made possible by the generous financial support of the W. M. Keck Foundation.
International Deep Planet Survey, 317 stars to determine the wide-separated planet frequency
NASA Astrophysics Data System (ADS)
Galicher, R.; Marois, C.; Macintosh, B.; Zuckerman, B.; Song, I.; Barman, T.; Patience, J.
2013-09-01
Since 2000, more than 300 nearby young stars were observed for the International Deep Planet Survey with adaptive optics systems at Gemini (NIRI/NICI), Keck (Nirc2), and VLT (Naco). Massive young AF stars were included in our sample whereas they have generally been neglected in first generation surveys because the contrast and target distances are less favorable to image substellar companions. The most significant discovery of the campaign is the now well-known HR 8799 multi-planet system. This remarkable finding allows, for the first time, an estimate of the Jovians planet population at large separations (further than a few AUs) instead of deriving upper limits. During my presentation, I will present the survey showing images of multiple stars and planets. I will then propose a statistic study of the observed stars deriving constraints on the Jupiter-like planet frequency at large separations.
Ultra-deep GEMINI Near-infrared Observations of the Bulge Globular Cluster NGC 6624.
NASA Astrophysics Data System (ADS)
Saracino, S.; Dalessandro, E.; Ferraro, F. R.; Geisler, D.; Mauro, F.; Lanzoni, B.; Origlia, L.; Miocchi, P.; Cohen, R. E.; Villanova, S.; Moni Bidin, C.
2016-11-01
We used ultra-deep J and K s images secured with the near-infrared (NIR) GSAOI camera assisted by the multi-conjugate adaptive optics system GeMS at the GEMINI South Telescope in Chile, to obtain a (K s , J - K s ) color-magnitude diagram (CMD) for the bulge globular cluster NGC 6624. We obtained the deepest and most accurate NIR CMD from the ground for this cluster, by reaching K s ˜ 21.5, approximately 8 mag below the horizontal branch level. The entire extension of the Main Sequence (MS) is nicely sampled and at K s ˜ 20 we detected the so-called MS “knee” in a purely NIR CMD. By taking advantage of the exquisite quality of the data, we estimated the absolute age of NGC 6624 (t age = 12.0 ± 0.5 Gyr), which turns out to be in good agreement with previous studies in the literature. We also analyzed the luminosity and mass functions of MS stars down to M ˜ 0.45 M⊙, finding evidence of a significant increase of low-mass stars at increasing distances from the cluster center. This is a clear signature of mass segregation, confirming that NGC 6624 is in an advanced stage of dynamical evolution. Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), Ministério da Ciência, Tecnologia e Inovação (Brazil) and Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina). Based on observations gathered with ESO-VISTA telescope (program ID 179.B-2002).
Binding behaviors of p-sulfonatocalix[4]arene with gemini guests.
Zhao, Hong-Xia; Guo, Dong-Sheng; Liu, Yu
2013-02-14
A dozen of homoditopic cations, possessing different spacer lengths and rigidities, as well as sizes, shapes, and charges of terminal groups, were synthesized as candidate gemini guests for the complexation of p-sulfonatocalix[4]arenes (SC4A). The 12 gemini guests are divided into five species according to the different terminal groups: imidazolium (G1-G3), pyridinium (G4-G6), quinolinium (G7), viologen (G8-G11), and 1,4-diazabicyclo[2.2.2]octane (DBO, G12). Their binding structures and stoichiometries with SC4A were examined by NMR spectroscopy, which is helpful to construct diverse highly ordered assemblies. The obtained results show that the length of the linkers, as well as the charge numbers on the end groups have a pronounced effect on the binding stoichiometry, whereas the size and shape of the terminal groups have no significant influence. Furthermore, both the stability constants and thermodynamic parameters of SC4A with the terminal subunits were determined by the isothermal titration calorimetry experiments, which are valuable to understand the binding behavior, giving quantitatively deep insight.
Crazy heart: kinematics of the "star pile" in Abell 545
NASA Astrophysics Data System (ADS)
Salinas, R.; Richtler, T.; West, M. J.; Romanowsky, A. J.; Lloyd-Davies, E.; Schuberth, Y.
2011-04-01
We study the structure and internal kinematics of the "star pile" in Abell 545 - a low surface brightness structure lying in the center of the cluster. We have obtained deep long-slit spectroscopy of the star pile using VLT/FORS2 and Gemini/GMOS, which is analyzed in conjunction with deep multiband CFHT/MEGACAM imaging. As presented in a previous study the star pile has a flat luminosity profile and its color is consistent with the outer parts of elliptical galaxies. Its velocity map is irregular, with parts being seemingly associated with an embedded nucleus, and others which have significant velocity offsets to the cluster systemic velocity with no clear kinematical connection to any of the surrounding galaxies. This would make the star pile a dynamically defined stellar intra-cluster component. The complicated pattern in velocity and velocity dispersions casts doubts on the adequacy of using the whole star pile as a dynamical test for the innermost dark matter profile of the cluster. This status is fulfilled only by the nucleus and its nearest surroundings which lie at the center of the cluster velocity distribution. Based on observations taken at the European Southern Observatory, Cerro Paranal, Chile, under programme ID 080.B-0529. Also based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the Science and Technology Facilities Council (United Kingdom), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), Ministério da Ciência e Tecnologia (Brazil) and SECYT (Argentina); and on observations obtained with MegaPrime/MegaCam, a joint project of CFHT and CEA/DAPNIA, at the Canada-France-Hawaii Telescope (CFHT) which is operated by the National Research Council (NRC) of Canada, the Institut National des Science de l'Univers of the Centre Natio nal de la Recherche Scientifique (CNRS) of France, and the University of Hawaii.
Gemini Rendezvous Docking Simulator
1964-05-11
Gemini Rendezvous Docking Simulator suspended from the roof of the Langley Research Center s aircraft hangar. Francis B. Smith wrote: The rendezvous and docking operation of the Gemini spacecraft with the Agena and of the Apollo Command Module with the Lunar Excursion Module have been the subject of simulator studies for several years. This figure illustrates the Gemini-Agena rendezvous docking simulator at Langley. The Gemini spacecraft was supported in a gimbal system by an overhead crane and gantry arrangement which provided 6 degrees of freedom - roll, pitch, yaw, and translation in any direction - all controllable by the astronaut in the spacecraft. Here again the controls fed into a computer which in turn provided an input to the servos driving the spacecraft so that it responded to control motions in a manner which accurately simulated the Gemini spacecraft. -- Published in Barton C. Hacker and James M. Grimwood, On the Shoulders of Titans: A History of Project Gemini, NASA SP-4203 Francis B. Smith, Simulators for Manned Space Research, Paper presented at the 1966 IEEE International convention, March 21-25, 1966.
New serine-derived gemini surfactants as gene delivery systems.
Cardoso, Ana M; Morais, Catarina M; Cruz, A Rita; Silva, Sandra G; do Vale, M Luísa; Marques, Eduardo F; de Lima, Maria C Pedroso; Jurado, Amália S
2015-01-01
Gemini surfactants have been extensively used for in vitro gene delivery. Amino acid-derived gemini surfactants combine the special aggregation properties characteristic of the gemini surfactants with high biocompatibility and biodegradability. In this work, novel serine-derived gemini surfactants, differing in alkyl chain lengths and in the linker group bridging the spacer to the headgroups (amine, amide and ester), were evaluated for their ability to mediate gene delivery either per se or in combination with helper lipids. Gemini surfactant-based DNA complexes were characterized in terms of hydrodynamic diameter, surface charge, stability in aqueous buffer and ability to protect DNA. Efficient formulations, able to transfect up to 50% of the cells without causing toxicity, were found at very low surfactant/DNA charge ratios (1/1-2/1). The most efficient complexes presented sizes suitable for intravenous administration and negative surface charge, a feature known to preclude potentially adverse interactions with serum components. This work brings forward a new family of gemini surfactants with great potential as gene delivery systems. Copyright © 2014 Elsevier B.V. All rights reserved.
Gemini Spectroscopic Survey of Young Intermediate-Mass Star-Forming Regions
NASA Astrophysics Data System (ADS)
Lundquist, Michael; Kobulnicky, Henry
2018-01-01
The majority of stars form in embedded clusters. Current research into star formation has focused on either high-mass star-forming regions or low-mass star-forming regions. We present the results from a Gemini spectroscopic survey of young intermediate-mass star-forming regions. These are star forming regions selected to produce stars up to but not exceeding 8 solar masses. We obtained spectra of these regions with GNIRS on Gemini North and Flamingos-2 on Gemini South. We also combine this with near-infrared imaging from 2MASS, UKIDSS, and VVV to study the stellar content.
A DEEP STUDY OF THE DWARF SATELLITES ANDROMEDA XXVIII AND ANDROMEDA XXIX
DOE Office of Scientific and Technical Information (OSTI.GOV)
Slater, Colin T.; Bell, Eric F.; Martin, Nicolas F.
We present the results of a deep study of the isolated dwarf galaxies Andromeda XXVIII and Andromeda XXIX with Gemini/GMOS and Keck/DEIMOS. Both galaxies are shown to host old, metal-poor stellar populations with no detectable recent star formation, conclusively identifying both of them as dwarf spheroidal galaxies (dSphs). And XXVIII exhibits a complex horizontal branch morphology, which is suggestive of metallicity enrichment and thus an extended period of star formation in the past. Decomposing the horizontal branch into blue (metal-poor, assumed to be older) and red (relatively more metal-rich, assumed to be younger) populations shows that the metal-rich are alsomore » more spatially concentrated in the center of the galaxy. We use spectroscopic measurements of the calcium triplet, combined with the improved precision of the Gemini photometry, to measure the metallicity of the galaxies, confirming the metallicity spread and showing that they both lie on the luminosity–metallicity relation for dwarf satellites. Taken together, the galaxies exhibit largely typical properties for dSphs despite their significant distances from M31. These dwarfs thus place particularly significant constraints on models of dSph formation involving environmental processes such as tidal or ram pressure stripping. Such models must be able to completely transform the two galaxies into dSphs in no more than two pericentric passages around M31, while maintaining a significant stellar population gradient. Reproducing these features is a prime requirement for models of dSph formation to demonstrate not just the plausibility of environmental transformation but the capability of accurately recreating real dSphs.« less
Meeting the challenges of bringing a new base facility operation model to Gemini Observatory
NASA Astrophysics Data System (ADS)
Nitta, Atsuko; Arriagada, Gustavo; Adamson, A. J.; Cordova, Martin; Nunez, Arturo; Serio, Andrew; Kleinman, Scot
2016-08-01
The aim of the Gemini Observatory's Base Facilities Project is to provide the capabilities to perform routine night time operations with both telescopes and their instruments from their respective base facilities without anyone present at the summit. Tightening budget constraints prompted this project as both a means to save money and an opportunity to move toward increasing remote operations in the future. We successfully moved Gemini North nighttime operation to our base facility in Hawaii in Nov., 2015. This is the first 8mclass telescope to completely move night time operations to base facility. We are currently working on implementing BFO to Gemini South. Key challenges for this project include: (1) This is a schedule driven project. We have to implement the new capabilities by the end of 2015 for Gemini North and end of 2016 for Gemini South. (2) The resources are limited and shared with operations which has the higher priority than our project. (3) Managing parallel work within the project. (4) Testing, commissioning and introducing new tools to operational systems without adding significant disruptions to nightly operations. (5) Staff buying to the new operational model. (6) The staff involved in the project are spread on two locations separated by 10,000km, seven time zones away from each other. To overcome these challenges, we applied two principles: "Bare Minimum" and "Gradual Descent". As a result, we successfully completed the project ahead of schedule at Gemini North Telescope. I will discuss how we managed the cultural and human aspects of the project through these concepts. The other management aspects will be presented by Gustavo Arriagada [2], the Project Manager of this project. For technical details, please see presentations from Andrew Serio [3] and Martin Cordova [4].
Sharma, Vishnu Dutt; Lees, Julia; Hoffman, Nicholas E.; Brailoiu, Eugen; Madesh, Muniswamy; Wunder, Stephanie L.; Ilies, Marc A.
2014-01-01
The study presents the effects of blending a cationic gemini surfactant into cationic lipid bilayers and its impact towards plasmid DNA compaction and delivery process. Using nanoDSC, dynamic light scattering, zeta potential and electrophoretic mobility measurements, together with transfection (2D- and 3D-) and viability assays, we identified the main physicochemical parameters of the lipid bilayers, liposomes and lipoplexes that are affected by the gemini surfactant addition. We also correlated the cationic bilayer composition with the dynamics of the DNA compaction process, and with transfection efficiency, cytotoxicity and internalization mechanism of the resultant nucleic acid complexes. We found that blending of gemini surfactant into the cationic bilayers fluidized the supramolecular assemblies, reduced the amount of positive charge required to fully compact the plasmid DNA and, in certain cases, changed the internalization mechanism of the lipoplexes. Transfection efficiency of select ternary lipoplexes derived from cationic gemini surfactants and lipids was several times superior to transfection efficiency of corresponding binary lipoplexes, also surpassing standard transfection systems. The overall impact of gemini surfactants into the formation and dynamic of cationic bilayers was found to depend heavily on the presence of co-lipids, their nature and amount present into lipoplexes. The study confirmed the possibility of combining the specific properties of pyridinium gemini surfactants and cationic lipids synergistically for obtaining efficient synthetic transfection systems with negligible cytotoxicity useful for therapeutic gene delivery. PMID:24377350
Multiple Exposure of Rendezvous Docking Simulator - Gemini Program
1964-02-07
Multiple exposure of Rendezvous Docking Simulator. Francis B. Smith, described the simulator as follows: The rendezvous and docking operation of the Gemini spacecraft with the Agena and of the Apollo Command Module with the Lunar Excursion Module have been the subject of simulator studies for several years. This figure illustrates the Gemini-Agena rendezvous docking simulator at Langley. The Gemini spacecraft was supported in a gimbal system by an overhead crane and gantry arrangement which provided 6 degrees of freedom - roll, pitch, yaw, and translation in any direction - all controllable by the astronaut in the spacecraft. Here again the controls fed into a computer which in turn provided an input to the servos driving the spacecraft so that it responded to control motions in a manner which accurately simulated the Gemini spacecraft. -- Published in Barton C. Hacker and James M. Grimwood, On the Shoulders of Titans: A History of Project Gemini, NASA SP-4203 Francis B. Smith, Simulators for Manned Space Research, Paper presented at the 1966 IEEE International convention, March 21-25, 1966.
NASA Astrophysics Data System (ADS)
Nord, Brian
2017-01-01
Strong gravitational lenses have potential as very powerful probes of dark energy and cosmic structure. However, efficiently finding lenses poses a significant challenge—especially in the era of large-scale cosmological surveys. I will present a new application of deep machine learning algorithms to find strong lenses, as well as the strong lens discovery program of the Dark Energy Survey (DES).Strong lenses provide unique information about the evolution of distant galaxies, the nature of dark energy, and the shapes of dark matter haloes. Current and future surveys, like DES and the Large Synoptic Survey Telescope, present an opportunity to find many thousands of strong lenses, far more than have ever been discovered. By and large, searches have heretofore relied on the time-consuming effort of human scanners. Deep machine learning frameworks, like convolutional neural nets, have revolutionized the task of image recognition, and have a natural place in the processing of astronomical images, including the search for strong lenses.Over five observing seasons, which started in August 2013, DES will carry out a wide-field survey of 5000 square degrees of the Southern Galactic Cap. DES has identified nearly 200 strong lensing candidates in the first two seasons of data. We have performed spectroscopic follow-up on a subsample of these candidates at Gemini South, confirming over a dozen new strong lenses. I will present this DES discovery program, including searches and spectroscopic follow-up of galaxy-scale, cluster-scale and time-delay lensing systems.I will focus, however, on a discussion of the successful search for strong lenses using deep learning methods. In particular, we show that convolutional neural nets present a new set of tools for efficiently finding lenses, and accelerating advancements in strong lensing science.
Vishvakarma, Vijay K; Kumari, Kamlesh; Patel, Rajan; Dixit, V S; Singh, Prashant; Mehrotra, Gopal K; Chandra, Ramesh; Chakrawarty, Anand Kumar
2015-05-15
Surfactants are used to prevent the irreversible aggregation of partially refolded proteins and they also assist in protein refolding. We have reported the design and screening of gemini surfactant to stabilize bovine serum albumin (BSA) with the help of computational tool (iGEMDOCK). A series of gemini surfactant has been designed based on bis-N-alkyl nicotinate dianion via varying the alkyl group and anion. On changing the alkyl group and anion of the surfactant, the value of Log P changes means polarity of surfactant can be tuned. Further, the virtual screening of the gemini surfactant has been carried out based on generic evolutionary method. Herein, thermodynamic data was studied to determine the potential of gemini surfactant as BSA stabilizer. Computational tools help to find out the efficient gemini surfactant to stabilize the BSA rather than to use the surfactant randomly and directionless for the stabilization. It can be confirmed through the experimental techniques. Previously, researcher synthesized one of the designed and used gemini surfactant to stabilize the BSA and their interactions were confirmed through various techniques and computational docking. But herein, the authors find the most competent gemini surfactant to stabilize BSA using computational tools on the basis of energy score. Different from the single chain surfactant, the gemini surfactants exhibit much stronger electrostatic and hydrophobic interactions with the protein and are thus effective at much lower concentrations. Based on the present study, it is expected that gemini surfactants may prove useful in the protein stabilization operations and may thus be effectively employed to circumvent the problem of misfolding and aggregation. Copyright © 2015 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Vishvakarma, Vijay K.; Kumari, Kamlesh; Patel, Rajan; Dixit, V. S.; Singh, Prashant; Mehrotra, Gopal K.; Chandra, Ramesh; Chakrawarty, Anand Kumar
2015-05-01
Surfactants are used to prevent the irreversible aggregation of partially refolded proteins and they also assist in protein refolding. We have reported the design and screening of gemini surfactant to stabilize bovine serum albumin (BSA) with the help of computational tool (iGEMDOCK). A series of gemini surfactant has been designed based on bis-N-alkyl nicotinate dianion via varying the alkyl group and anion. On changing the alkyl group and anion of the surfactant, the value of Log P changes means polarity of surfactant can be tuned. Further, the virtual screening of the gemini surfactant has been carried out based on generic evolutionary method. Herein, thermodynamic data was studied to determine the potential of gemini surfactant as BSA stabilizer. Computational tools help to find out the efficient gemini surfactant to stabilize the BSA rather than to use the surfactant randomly and directionless for the stabilization. It can be confirmed through the experimental techniques. Previously, researcher synthesized one of the designed and used gemini surfactant to stabilize the BSA and their interactions were confirmed through various techniques and computational docking. But herein, the authors find the most competent gemini surfactant to stabilize BSA using computational tools on the basis of energy score. Different from the single chain surfactant, the gemini surfactants exhibit much stronger electrostatic and hydrophobic interactions with the protein and are thus effective at much lower concentrations. Based on the present study, it is expected that gemini surfactants may prove useful in the protein stabilization operations and may thus be effectively employed to circumvent the problem of misfolding and aggregation.
Revealing the nebular properties and Wolf-Rayet population of IC10 with Gemini/GMOS
NASA Astrophysics Data System (ADS)
Tehrani, Katie; Crowther, Paul A.; Archer, I.
2017-12-01
We present a deep imaging and spectroscopic survey of the Local Group irregular galaxy IC10 using Gemini North and GMOS to unveil its global Wolf-Rayet (WR) population. We obtain a star formation rate (SFR) of 0.045 ± 0.023 M⊙ yr-1, for IC10 from the nebular H α luminosity, which is comparable to the Small Magellanic Cloud. We also present a revised nebular oxygen abundance of log(O/H) + 12 = 8.40 ± 0.04, comparable to the LMC. It has previously been suggested that for IC10 to follow the WR subtype-metallicity dependance seen in other Local Group galaxies, a large WN population awaits discovery. Our search revealed three new WN stars, and six candidates awaiting confirmation, providing little evidence to support this claim. The new global WR star total of 29 stars is consistent with the Large Magellanic Cloud population when scaled to the reduced SFR of IC10. For spectroscopically confirmed WR stars, the WC/WN ratio is lowered to 1.0; however, including all potential candidates, and assuming those unconfirmed to be WN stars, would reduce the ratio to ∼0.7. We attribute the high WC/WN ratio to the high star formation surface density of IC10 relative to the Magellanic Clouds, which enhances the frequency of high-mass stars capable of producing WC stars.
Zhao, Shan; Huang, Gordon; An, Chunjiang; Wei, Jia; Yao, Yao
2015-04-09
The enhancement of soil retention for phenanthrene (PHE) through the addition of a binary mixture of cationic gemini (12-2-12) and nonionic surfactants (C12E10) was investigated. The maximum apparent sorption coefficient Kd(*) reached 4247.8 mL/g through the addition of mixed 12-2-12 gemini and C12E10 surfactants, which was markedly higher than the summed individual results in the presence of individual 12-2-12 gemini (1148.6 mL/g) or C12E10 (210.0 mL/g) surfactant. However, the sorption of 12-2-12 gemini was inhibited by the increasing C12E10 dose; and a higher initial 12-2-12 gemini dose showed a higher "desorption" rate. The present study also addressed the sorption behavior of the single 12-2-12 gemini surfactant at the soil/aqueous interface. The sorption isotherm was divided into two steps to elucidate the sorption process; and the sorption schematics were proposed to elaborate the growth of surfactant aggregates corresponding to the various steps of the sorption isotherm. Finally, a two-step adsorption and partition model (TAPM) was developed to simulate the sorption process. Analysis of the equilibrium data indicated that the sorption isotherms of 12-2-12 gemini fitted the TAPM model better. Thermodynamic calculations confirmed that the 12-2-12 gemini sorption at the soil/aqueous interface was spontaneous and exothermic from 288 to 308K. Copyright © 2014 Elsevier B.V. All rights reserved.
Dicationic Alkylammonium Bromide Gemini Surfactants. Membrane Perturbation and Skin Irritation
Almeida, João A. S.; Faneca, Henrique; Carvalho, Rui A.; Marques, Eduardo F.; Pais, Alberto A. C. C.
2011-01-01
Dicationic alkylammonium bromide gemini surfactants represent a class of amphiphiles potentially effective as skin permeation enhancers. However, only a limited number of studies has been dedicated to the evaluation of the respective cytotoxicity, and none directed to skin irritation endpoints. Supported on a cell viability study, the cytotoxicity of gemini surfactants of variable tail and spacer length was assessed. For this purpose, keratinocyte cells from human skin (NCTC 2544 cell line), frequently used as a model for skin irritation, were employed. The impact of the different gemini surfactants on the permeability and morphology of model vesicles was additionally investigated by measuring the leakage of calcein fluorescent dye and analyzing the NMR spectra of 31P, respectively. Detail on the interaction of gemini molecules with model membranes was also provided by a systematic differential scanning calorimetry (DSC) and molecular dynamics (MD) simulation. An irreversible impact on the viability of the NCTC 2544 cell line was observed for gemini concentrations higher than 25 mM, while no cytotoxicity was found for any of the surfactants in a concentration range up to 10 mM. A higher cytotoxicity was also found for gemini surfactants presenting longer spacer and shorter tails. The same trend was obtained in the calorimetric and permeability studies, with the gemini of longest spacer promoting the highest degree of membrane destabilization. Additional structural and dynamical characterization of the various systems, obtained by 31P NMR and MD, provide some insight on the relationship between the architecture of gemini surfactants and the respective perturbation mechanism. PMID:22102870
Women Astronomers at Gemini: A Success Story
NASA Astrophysics Data System (ADS)
Rodgers, Bernadette; Jorgensen, I.; Barker, N.; Edwards, M.; Trancho, G.
2010-01-01
Gemini Observatory has been very successful at attracting, hiring and retaining female Scientists. We present data on the growth of the scientific staff since the start of the Observatory, and science fellow recruiting from 2006-2008. At Gemini 31% of the Science Staff holding PhDs are female compared with 13.9% within the United States. The Science Management is 75% female, as is 50% of the Gemini Directorate. This critical mass of female representation within the science staff and management appears to have had a positive effect on female recruitment and hiring. The science fellow recruitment during the past 3 years has attracted 21-38% female applicants and 57% of new hires during this period have been female scientists. Perhaps even more significant, the retention rate of female science staff at Gemini is 88%, compared to 64% for male science staff. There are likely many factors that contribute to this success, but the conclusion is that Gemini has earned a reputation in the scientific community as a place where female scientists are valued and can be successful.
Sharma, Vishnu Dutt; Ilies, Marc A
2014-01-01
Gemini surfactants (GS) are presently receiving substantial attention due to their special self-assembling properties and unique interfacial activity. This comprehensive review is focused on positively charged heterocyclic GS, presenting their major synthetic access routes and examining the impact of structural elements on physicochemical and aggregation properties of this class of amphiphiles. Interaction of geminis surfactants with cells and their biological properties as novel transfection agents are emphasized through a detailed structure-activity relationship analysis. Throughout the review we have also presented the properties of selected ammonium GS, simple surfactants and lipid congeners, in order to emphasize the advantages conferred by using heterocyclic polar heads in GS design. © 2012 Wiley Periodicals, Inc.
1966-07-18
S66-42738 (18 July 1966) --- Astronaut John W. Young, Gemini-10 command pilot, holds a pair of king-size pliers presented to him by the crew at Pad 19 for in-flight first-echelon maintenance of a spacecraft utility power cord Young earlier had difficulty in connecting. Gunther Wendt (right center background), Pad 19 leader, jokes with Young about the pliers. At right is Dr. Donald K. Slayton, MSC Director of Flight Crew Operations. At left is astronaut Michael Collins, Gemini-10 pilot. Photo credit: NASA
The Software Distribution for Gemini Observatory's Science Operations Group
NASA Astrophysics Data System (ADS)
Hoenig, M. D.; Clarke, M.; Pohlen, M.; Hirst, P.
2014-05-01
Gemini Observatory consists of two telescopes in different hemispheres. It also operates mostly on a queue observing model, meaning observations are performed by staff working shifts as opposed to PIs. For these two reasons alone, maintaining and distributing a diverse software suite is not a trivial matter. We present a way to make the appropriate tools available to staff at Gemini North and South, whether they are working on the summit or from our base facility offices in Hilo, Hawai'i and La Serena, Chile.
bHROS: A New High-Resolution Spectrograph Available on Gemini South
NASA Astrophysics Data System (ADS)
Margheim, S. J.; Gemini bHROS Team
2005-12-01
The Gemini bench-mounted High-Resolution Spectrograph (bHROS) is available for science programs beginning in 2006A. bHROS is the highest resolution (R=150,000) optical echelle spectrograph optimized for use on an 8-meter telescope. bHROS is fiber-fed via GMOS-S from the Gemini South focal plane and is available in both a dual-fiber Object/Sky mode and a single (larger) Object-only mode. Instrument characteristics and sample data taken during commissioning will be presented.
Long-term Efficacy of Vedolizumab for Crohn's Disease.
Vermeire, Severine; Loftus, Edward V; Colombel, Jean-Frédéric; Feagan, Brian G; Sandborn, William J; Sands, Bruce E; Danese, Silvio; D'Haens, Geert R; Kaser, Arthur; Panaccione, Remo; Rubin, David T; Shafran, Ira; McAuliffe, Megan; Kaviya, Arpeat; Sankoh, Serap; Mody, Reema; Abhyankar, Brihad; Smyth, Michael
2017-04-01
Vedolizumab is a gut-selective α4β7 integrin antagonist therapy for ulcerative colitis and Crohn's disease. The GEMINI long-term safety [LTS] trial is an ongoing open-label study investigating the safety of vedolizumab. We present interim exploratory analyses of efficacy in patients with Crohn's disease. Patients from the C13004, GEMINI 2 and GEMINI 3 studies and vedolizumab-naïve patients could enrol in GEMINI LTS and received vedolizumab every 4 weeks. Data were collected from May 22, 2009 to June 27, 2013. Outcomes of clinical response and remission, defined by the Harvey-Bradshaw Index, and health-related quality of life [HRQL] were assessed for up to 152 weeks of treatment in the efficacy population. Among patients with response at week 6 in GEMINI 2 who received vedolizumab continuously, 83% [n=100/120] and 89% [n=62/70] of patients with available data were in remission after 104 and 152 weeks, respectively. Increased dosing frequency from every 8 weeks [GEMINI 2] to every 4 weeks [GEMINI LTS] improved outcomes in patients who had withdrawn early from GEMINI 2, with 47% [n=27/57] experiencing clinical response and 32% [n=18/57] in remission at week 52 of GEMINI LTS [up from 39% and 4% before the dose increase]. Similar improvements were observed regardless of prior tumour necrosis factor [TNF] antagonist exposure. Long-term benefits of HRQL were also observed. The clinical benefits of vedolizumab continued with long-term treatment regardless of prior TNF antagonist exposure. Increased dosing frequency might improve outcomes in patients who lose response to conventional 8-weekly dosing. Copyright © 2016 European Crohn’s and Colitis Organisation (ECCO). Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com
The Gemini Science User Support Department: A community-centered approach to user support
NASA Astrophysics Data System (ADS)
Chené, André-Nicolas; Thomas-Osip, Joanna
2016-01-01
The Gemini Science User Support Department (SUSD) was formed a little more than a year ago to create a collaborative community of users and staff and to consolidate existing post-observing support throughout the observatory for more efficient use of resources as well as better visibility amongst our user community. This poster is an opportunity to exchange ideas about how Gemini can improve your experience while working with the Observatory and present details about new avenues of post-observing support coming soon. We encourage your feedback at any time.Shortly after its creation, the SUSD conducted a complete revision of the communication cycle between Gemini and its community of researchers. The cycle was then revisited from the perspective of an astronomer interested in using Gemini for their research. This exercise led to a series of proposed changes that are currently under development, and the implementation of a sub-selection is expected in 2016, including the following. (1) Email notifications: Gemini users will receive new forms of email communications that are more instructive and tailored to their program. The objective is to direct the users more efficiently toward the useful links and documentation all along the lifecycle of the program, from phaseII to after the data are completely reduced. (2) HelpDesk system: The HelpDesk will become more user-friendly and transparent. (3) Webpages: The organization of the Gemini webpages will be redesigned to optimize navigation; especially for anything regarding more critical periods likes phaseIs and phaseIIs. (4) Data Reduction User Forum: Following recommendations from Gemini users, new capabilities were added to the forum, like email notifications, and a voting system, in order to make it more practical. This forum's objective is to bring the Gemini community together to exchange their ideas, thoughts, questions and solutions about data reduction, a sort of Reddit, StackOverflow or Slashdot for Gemini data.
The Search for Wolf-Rayet Stars in IC10
NASA Astrophysics Data System (ADS)
Tehrani, Katie; Crowther, Paul; Archer, Isabelle
2017-11-01
We present a deep imaging and spectroscopic survey of the Local Group starburst galaxy IC10 using Gemini North/GMOS to unveil the global Wolf-Rayet population. It has previously been suggested that for IC10 to follow the WC/WN versus metallicity dependence seen in other Local Group galaxies, a large WN population must remain undiscovered. Our search revealed 3 new WN stars, and 5 candidates awaiting confirmation, providing little evidence to support this claim. We also compute an updated nebular derived metallicity of log(O/H)+12=8.40 +/- 0.04 for the galaxy using the direct method. Inspection of IC10 WR average line luminosities show these stars are more similar to their LMC, rather than SMC counterparts.
Summary analysis of the Gemini entry aerodynamics
NASA Technical Reports Server (NTRS)
Whitnah, A. M.; Howes, D. B.
1972-01-01
The aerodynamic data that were derived in 1967 from the analysis of flight-generated data for the Gemini entry module are presented. These data represent the aerodynamic characteristics exhibited by the vehicle during the entry portion of Gemini 2, 3, 5, 8, 10, 11, and 12 missions. For the Gemini, 5, 8, 10, 11, and 12 missions, the flight-generated lift-to-drag ratios and corresponding angles of attack are compared with the wind tunnel data. These comparisons show that the flight generated lift-to-drag ratios are consistently lower than were anticipated from the tunnel data. Numerous data uncertainties are cited that provide an insight into the problems that are related to an analysis of flight data developed from instrumentation systems, the primary functions of which are other than the evaluation of flight aerodynamic performance.
Tectonic map of the Arabian Peninsula
Brown, Glen F.
1972-01-01
This tectonic map of the Arabian peninsula, prepared for the Audi Arabian Ministry of Petroleum and Mineral Resource, is the first of a series of peninsular maps that attempt to show regional features. Much recent information resulting from detailed geologic mapping notably within the Arabian craton, from geophysical surveys, both airborne and oceanographic in adjacent seas, from deep exploratory drilling, and from photography from the Gemini and Apollo space programs, has been used in the tectonic evaluation.
Now Open Operations View All Observing databases offline May 30 Status of Gemini North eNewscast View Gemini Observatory Strategic Vision PDF Gemini North with open wind vents and observing slit at sunset . Gemini South with star-trails of the South Celestial Pole overhead. Gemini Science Meeting Open For
Design and analysis of the Gemini chain system in dual clutch transmission of automobile
NASA Astrophysics Data System (ADS)
Cheng, Yabing; Guo, Haitao; Fu, Zhenming; Wan, Nen; Li, Lei; Wang, Yang
2015-01-01
Chain drive system is widely used in the conditions of high-speed, overload, variable speed and load. Many studies are focused on the meshing theory and wear characteristics of chain drive system, but system design, analysis, and noise characteristics of the chain drive system are weak. System design and noise characteristic are studied for a new type Gemini chain of dual-clutch automatic transmission. Based on the meshing theory of silent chain, the design parameters of the Gemini chain system are calculated and the mathematical models and dynamic analysis models of the Gemini chain system are established. Dynamic characteristics of the Gemini chain system is simulated and the contact force of plate and pin, plate and sprockets, the chain tension forces, the transmission error and the stress of plates and pins are analyzed. According to the simulation results of the Gemini chain system, the noise experiment about system is carried out. The noise values are tested at different speed and load and spectral characteristics are analyzed. The results of simulation and experimental show that the contact forces of plate and pin, plate and sprockets are smaller than the allowable stress values, the chain tension force is less than ultimate tension and transmission error is limited in 1.2%. The noise values can meet the requirements of industrial design, and it is proved that the design and analysis method of the Gemini chain system is scientific and feasible. The design and test system is built from analysis to test of Gemini chain system. This research presented will provide a corresponding theoretical guidance for the design and dynamic characteristics and noise characteristics of chain drive system.
Gemini rendezvous docking simulator
1963-11-04
Multiple exposure of Gemini rendezvous docking simulator. Francis B. Smith wrote in his paper "Simulators for Manned Space Research," "The rendezvous and docking operation of the Gemini spacecraft with the Agena and of the Apollo Command Module with the Lunar Excursion Module have been the subject of simulator studies for several years. [This figure] illustrates the Gemini-Agena rendezvous docking simulator at Langley. The Gemini spacecraft was supported in a gimbal system by an overhead crane and gantry arrangement which provided 6 degrees of freedom - roll, pitch, yaw, and translation in any direction - all controllable by the astronaut in the spacecraft. Here again the controls fed into a computer which in turn provided an input to the servos driving the spacecraft so that it responded to control motions in a manner which accurately simulated the Gemini spacecraft." A.W. Vogeley further described the simulator in his paper "Discussion of Existing and Planned Simulators For Space Research," "Docking operations are considered to start when the pilot first can discern vehicle target size and aspect and terminate, of course, when soft contact is made. ... This facility enables simulation of the docking operation from a distance of 200 feet to actual contact with the target. A full-scale mock-up of the target vehicle is suspended near one end of the track. ... On [the Agena target] we have mounted the actual Agena docking mechanism and also various types of visual aids. We have been able to devise visual aids which have made it possible to accomplish nighttime docking with as much success as daytime docking." -- Published in Barton C. Hacker and James M. Grimwood, On the Shoulders of Titans: A History of Project Gemini, NASA SP-4203; Francis B. Smith, "Simulators for Manned Space Research," Paper presented at the 1966 IEEE International convention, March 21-25, 1966; A.W. Vogeley, "Discussion of Existing and Planned Simulators For Space Research," Paper presented at the Conference on the Role of Simulation in Space Technology, August 17-21, 1964.
NASA Astrophysics Data System (ADS)
Tripathy, Divya Bajpai; Mishra, Anuradha
Gemini surfactants are presently gaining attention due to their unusual self-assembling characteristics and incomparable interfacial activity. Current research work involves the cost-effective microwave (MW) synthesis of waste soybean oil-based gemini imidazolinium surfactants (GIS) having a carbonate linkage in its spacer moiety. Structural characterizations of the materials have been done using FT-IR, 1H-NMR and 13C-NMR. Using indigenous and natural material as base and MW as energy source for synthesizing the GIS with easily degradable chemical moiety make them to be labeled as green surfactants.
ULTRA-DEEP GEMINI NEAR-INFRARED OBSERVATIONS OF THE BULGE GLOBULAR CLUSTER NGC 6624
DOE Office of Scientific and Technical Information (OSTI.GOV)
Saracino, S.; Dalessandro, E.; Ferraro, F. R.
2016-11-20
We used ultra-deep J and K {sub s} images secured with the near-infrared (NIR) GSAOI camera assisted by the multi-conjugate adaptive optics system GeMS at the GEMINI South Telescope in Chile, to obtain a ( K {sub s} , J - K {sub s} ) color–magnitude diagram (CMD) for the bulge globular cluster NGC 6624. We obtained the deepest and most accurate NIR CMD from the ground for this cluster, by reaching K {sub s} ∼ 21.5, approximately 8 mag below the horizontal branch level. The entire extension of the Main Sequence (MS) is nicely sampled and at K {submore » s} ∼ 20 we detected the so-called MS “knee” in a purely NIR CMD. By taking advantage of the exquisite quality of the data, we estimated the absolute age of NGC 6624 ( t {sub age} = 12.0 ± 0.5 Gyr), which turns out to be in good agreement with previous studies in the literature. We also analyzed the luminosity and mass functions of MS stars down to M ∼ 0.45 M{sub ⊙}, finding evidence of a significant increase of low-mass stars at increasing distances from the cluster center. This is a clear signature of mass segregation, confirming that NGC 6624 is in an advanced stage of dynamical evolution.« less
NASA Technical Reports Server (NTRS)
1965-01-01
The insignia of the Gemini space program is a disc of dark blue as a background for a gold Zodiac Gemini symbol. A white star on each of the two vertical curves of the Gemini symbol represent the Gemini twins, Pollux and Castor.
A new approach for instrument software at Gemini
NASA Astrophysics Data System (ADS)
Gillies, Kim; Nunez, Arturo; Dunn, Jennifer
2008-07-01
Gemini Observatory is now developing its next generation of astronomical instruments, the Aspen instruments. These new instruments are sophisticated and costly requiring large distributed, collaborative teams. Instrument software groups often include experienced team members with existing mature code. Gemini has taken its experience from the previous generation of instruments and current hardware and software technology to create an approach for developing instrument software that takes advantage of the strengths of our instrument builders and our own operations needs. This paper describes this new software approach that couples a lightweight infrastructure and software library with aspects of modern agile software development. The Gemini Planet Imager instrument project, which is currently approaching its critical design review, is used to demonstrate aspects of this approach. New facilities under development will face similar issues in the future, and the approach presented here can be applied to other projects.
Thermodynamic investigation of the binding of dissymmetric pyrenyl-gemini surfactants to DNA.
Wettig, Shawn D; Deubry, Rubena; Akbar, Javed; Kaur, Tranum; Wang, Haitang; Sheinin, Tatiana; Joseph, Jamie W; Slavcev, Roderick A
2010-05-14
Gemini surfactants have demonstrated significant potential for use in constructing non-viral transfection vectors for the delivery of genes into cells to induce protein expression. Previously, two asymmetric gemini surfactants containing pyrenyl groups in one of the alkyl tails of the surfactants were synthesized as fluorescence probes for use in mechanistic studies of the transfection process. Here we present the results of a thermodynamic investigation of the binding interaction(s) between the pyrenyl-modified surfactants and DNA. The thermodynamics of the interactions have been examined using isothermal titration calorimetry, light scattering, zeta potential, and circular dichroism measurements. Distinct differences are observed between the interaction of 12-s-12 vs. the pyrene modified py-s-12 surfactants with DNA; an intercalated binding is found for the py-s-12 surfactants that disrupts the typical interactions observed between DNA and gemini surfactants.
Gemini Program Mission Report for Gemini-Titan 1 (GT-1)
NASA Technical Reports Server (NTRS)
1964-01-01
The Gemini-Titan 1 (GT-1) space vehicle was comprised of the Gemini spacecraft and the Gemini launch vehicle. The Gemini launch vehicle is a two-stage modified Titan II ICBM. The major modifications are the addition of a malfunction detection system and a secondary flight controls system. The Gemini spacecraft, designed to carry a crew of two men on earth orbital and rendezvous missions, was unmanned for the flight reported herein (GT-1). There were no complete Gemini flight systems on board; however, the C-band transponder and telemetry transmitters were Gemini flight subsystems. Dummy equipment, having a mass and moment of inertia equal to flight system equipment, was installed in the spacecraft. The Spacecraft was instrumented to obtain data on spacecraft heating, structural loading, vibration, sound pressure levels, and temperature and pressure during the launch phase.
The Stacked LYα Emission Profile from the Circum-Galactic Medium of z ˜ 2 Quasars
NASA Astrophysics Data System (ADS)
Arrigoni Battaia, Fabrizio; Hennawi, Joseph F.; Cantalupo, Sebastiano; Prochaska, J. Xavier
2016-09-01
In the context of the FLASHLIGHT survey, we obtained deep narrowband images of 15 z ˜ 2 quasars with the Gemini Multi-object Spectrograph on Gemini South in an effort to measure Lyα emission from circum- and intergalactic gas on scales of hundreds of kpc from the central quasar. We do not detect bright giant Lyα nebulae (SB ˜ 10-17 erg s-1 cm-2 arcsec-2 at distances >50 kpc) around any of our sources, although we routinely (≃47%) detect smaller-scale <50 kpc Lyα emission at this surface brightness level emerging from either the extended narrow emission line regions powered by the quasars or by star formation in their host galaxies. We stack our 15 deep images to study the average extended Lyα surface brightness profile around z ˜ 2 quasars, carefully PSF-subtracting the unresolved emission component and paying close attention to sources of systematic error. Our analysis, which achieves an unprecedented depth, reveals a surface brightness of SBLyα ˜ 10-19 erg s-1 cm-2 arcsec-2 at ˜200 kpc, with a 2.3σ detection of Lyα emission at SB {}{Lyα }=(5.5+/- 3.1)× {10}-20 erg s-1 cm-2 arcsec-2 within an annulus spanning 50 kpc < R < 500 kpc from the quasars. Assuming that this Lyα emission is powered by fluorescence from highly ionized gas illuminated by the bright central quasar, we deduce an average volume density of n H = 0.6 × 10-2 cm-3 on these large scales. Our results are in broad agreement with the densities suggested by cosmological hydrodynamical simulations of massive (M ≃ 1012.5 M ⊙) quasar hosts; however, they indicate that the typical quasars at these redshifts are surrounded by gas that is a factor of ˜100 times less dense than the (˜1 cm-3) gas responsible for the giant bright Lyα nebulae around quasars recently discovered by our group. Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), Ministério da Ciência, Tecnologia e Inovação (Brazil), and Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina).
Liu, Songbai; Sang, Ruocheng; Hong, Shan; Cai, Yujing; Wang, Hua
2013-07-09
A novel type of highly effective gemini alkyl glucosides has been rationally designed and synthesized. The gemini surfactants have been readily prepared by glycosylation of the gemini alkyl chains that are synthesized with regioselective ring-opening of ethylene glycol epoxides by the alkyl alcohols. The new gemini alkyl glucosides exhibit significantly better surface activity than the known results. Then rheological, DLS, and TEM studies have revealed the intriguing self-assembly behavior of the novel gemini surfactants. This study has proved the effectiveness of the design of gemini alkyl glucosides which is modular, extendable, and synthetically simple. The new gemini surfactants have great potential as nano carriers in drug and gene delivery.
VizieR Online Data Catalog: Brown dwarfs with spectral type later than T6 (Leggett+, 2017)
NASA Astrophysics Data System (ADS)
Leggett, S. K.; Tremblin, P.; Esplin, T. L.; Luhman, K. L.; Morley, C. V.
2018-01-01
We present the new GNIRS and FLAMINGOS-2 spectra and the new NIRI photometry in section 4 (see also table 1). We obtained a 0.95<=λ(um)<=2.5 spectrum using GNIRS at Gemini North on 2016 December 24 and 25 via program GN-2016B-Q-46 for WISEAJ041022.75+150247.9 with R~700. We also obtained near-infrared spectra for WISEJ071322.55-291751.9 and WISEAJ114156.67-332635.5 using FLAMINGOS-2 at Gemini South on 2017 February 3 and 7, via program GS-2017A-FT-2. The JH grism was used giving R~600. We obtained photometry for WISE J085510.83-071442.5 on Gemini North using NIRI at Y and CH4(short) via program GN-2016A-Q-50, and at M' via program GN-2016A-FT-10 between 2015 December and 2016 March. The M' data for a sample of T and Y dwarfs was obtained via program GN-2016B-Q-46 using NIRI on Gemini North. Finally, we obtained H data for the Y1 WISEA J064723.24-623235.4 using FLAMINGOS-2 on Gemini South, which were presented in Leggett+ (2013ApJ...763..130L). We also obtained new photometry from HST/WFC3, ESO VLT HAWK-I and Spitzer/IRAC and WISE archives; see section 5 and tables 2 and 3. (7 data files).
Remote Operations of Laser Guide Star Systems: Gemini Observatory.
NASA Astrophysics Data System (ADS)
Oram, Richard J.; Fesquet, Vincent; Wyman, Robert; D'Orgeville, Celine
2011-03-01
The Gemini North telescope, equipped with a 14W laser, has been providing Laser Guide Star Adaptive Optics (LGS AO) regular science queue observations for worldwide astronomers since February 2007. The new 55W laser system for MCAO was installed on the Gemini South telescope in May 2010. In this paper, we comment on how Gemini Observatory developed regular remote operation of the Laser Guide Star Facility and high-power solid-state laser as routine normal operations. Fully remote operation of the LGSF from the Hilo base facility HBF was initially trialed and then optimized and became the standard operating procedure (SOP) for LGS operation in December 2008. From an engineering perspective remote operation demands stable, well characterized and base-lined equipment sets. In the effort to produce consistent, stable and controlled laser parameters (power, wavelength and beam quality) we completed a failure mode effect analysis of the laser system and sub systems that initiated a campaign of hardware upgrades and procedural improvements to the routine maintenance operations. Finally, we provide an overview of normal operation procedures during LGS runs and present a snapshot of data accumulated over several years that describes the overall LGS AO observing efficiency at the Gemini North telescope.
Gemini-Titan (GT)-7 of GT-6 Space Photography - Outer Space
1965-12-04
S65-64040 (15 Dec. 1965) --- Nose-on view of the Gemini-6 spacecraft against the blackness of space as seen from Gemini-7 spacecraft. The two spacecraft were approximately 38 feet apart. Astronauts Walter M. Schirra and Thomas P. Stafford were onboard the Gemini-6 spacecraft. Astronauts Frank Borman and James A. Lovell Jr. were aboard the Gemini-7 spacecraft. A "Beat Army" sign can be seen in the Gemini-6 window. Photo credit: NASA
Deep g'r'i'z' GMOS Imaging of the Dwarf Irregular Galaxy Kar 50
NASA Astrophysics Data System (ADS)
Davidge, T. J.
2002-11-01
Images obtained with the Gemini Multi-Object Spectrograph (GMOS) are used to investigate the stellar content and distance of the dwarf irregular galaxy Kar 50. The brightest object is an H II region, and the bright stellar content is dominated by stars with g'-r'<0. The tips of the main sequence and the red giant branch (RGB) are tentatively identified near r'=24.9 and i'=25.5, respectively. The galaxy has a blue integrated color and no significant color gradient, and we conclude that Kar 50 has experienced a recent galaxy-wide episode of star formation. The distance estimated from the brightest blue stars indicates that Kar 50 is behind the M81 group, and this is consistent with the tentative RGB-tip brightness. Kar 50 has a remarkably flat central surface brightness profile, even at wavelengths approaching 1 μm, although there is no evidence of a bar. In the absence of another large star-forming episode, Kar 50 will evolve into a very low surface brightness galaxy. Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the Particle Physics and Astronomy Research Council (United Kingdom), the National Research Council of Canada (Canada), CONICYT (Chile), the Australian Research Council (Australia), CNPq (Brazil), and CONICET (Argentina).
GEMINI: a computationally-efficient search engine for large gene expression datasets.
DeFreitas, Timothy; Saddiki, Hachem; Flaherty, Patrick
2016-02-24
Low-cost DNA sequencing allows organizations to accumulate massive amounts of genomic data and use that data to answer a diverse range of research questions. Presently, users must search for relevant genomic data using a keyword, accession number of meta-data tag. However, in this search paradigm the form of the query - a text-based string - is mismatched with the form of the target - a genomic profile. To improve access to massive genomic data resources, we have developed a fast search engine, GEMINI, that uses a genomic profile as a query to search for similar genomic profiles. GEMINI implements a nearest-neighbor search algorithm using a vantage-point tree to store a database of n profiles and in certain circumstances achieves an [Formula: see text] expected query time in the limit. We tested GEMINI on breast and ovarian cancer gene expression data from The Cancer Genome Atlas project and show that it achieves a query time that scales as the logarithm of the number of records in practice on genomic data. In a database with 10(5) samples, GEMINI identifies the nearest neighbor in 0.05 sec compared to a brute force search time of 0.6 sec. GEMINI is a fast search engine that uses a query genomic profile to search for similar profiles in a very large genomic database. It enables users to identify similar profiles independent of sample label, data origin or other meta-data information.
Measurements of airglow on Maunakea at Gemini Observatory
NASA Astrophysics Data System (ADS)
Roth, Katherine C.; Smith, Adam; Stephens, Andrew; Smirnova, Olesja
2016-07-01
Gemini Observatory on Maunakea has been collecting optical and infrared science data for almost 15 years. We have begun a program to analyze imaging data from two of the original facility instruments, GMOS and NIRI, in order to measure sky brightness levels in multiple infrared and optical broad-band filters. The present work includes data from mid-2016 back through late-2008. We present measured background levels as a function of several operational quantities (e.g. moon phase, hours from twilight, season). We find that airglow is a significant contributor to background levels in several filters. Gemini is primarily a queue scheduled telescope, with observations being optimally executed in order to provide the most efficient use of telescope time. We find that while most parameters are well-understood, the atmospheric airglow remains challenging to predict. This makes it difficult to schedule observations which require dark skies in these filters, and we suggest improvements to ensure data quality.
Instrument Performance Monitoring at Gemini North
NASA Astrophysics Data System (ADS)
Emig, Kimberly; Pohlen, M.; Chene, A.
2014-01-01
An instrument performance monitoring (IPM) project at the Gemini North Observatory evaluates the delivered throughput and sensitivity of, among other instruments, the Near-Infrared Integral Field Spectrometer (NIFS), the Gemini Near-Infrared Spectrograph (GNIRS), and the Gemini Multi-Object Spectrograph (GMOS-N). Systematic observations of standard stars allow the quality of the instruments and mirror to be assessed periodically. An automated pipeline has been implemented to process and analyze data obtained with NIFS, GNIRS cross-dispersed (XD) and long slit (LS) modes, and GMOS (photometry and spectroscopy). We focus the discussion of this poster on NIFS and GNIRS. We present the spectroscopic throughput determined for ZJHK bands on NIFS, the XJHKLM band for GNIRS XD mode and the K band for GNIRS LS. Additionally, the sensitivity is available for the JHK bands in NIFS and GNIRS XD, and for the K band in GNIRS LS. We consider data taken as early as March 2011. Furthermore, the pipeline setup and the methods used to determine throughput and sensitivity are described.
ASTRONAUT GROUP - GT-6 AND GT-7 CREWS - WELCOME
1965-12-19
S65-66728 (19 Dec. 1965) --- This happy round of handshakes took place in the Manned Spacecraft Operations Building crew quarters, Merritt Island, as the Gemini-6 crew (left) welcomed the Gemini-7 crew back to the Kennedy Space Center. Left to right, are astronauts Walter M. Schirra Jr., Gemini-6 command pilot; Thomas P. Stafford, Gemini-6 pilot; Frank Borman, Gemini-7 command pilot; James A. Lovell Jr., Gemini-7 pilot; and Donald K. Slayton (partially hidden behind Lovell), assistant director for Flight Crew Operations, Manned Spacecraft Center, Houston. Photo credit: NASA
NASA Astrophysics Data System (ADS)
Cordova, Martin; Serio, Andrew; Meza, Francisco; Arriagada, Gustavo; Swett, Hector; Ball, Jesse; Collins, Paul; Masuda, Neal; Fuentes, Javier
2016-07-01
In 2014 Gemini Observatory started the base facility operations (BFO) project. The project's goal was to provide the ability to operate the two Gemini telescopes from their base facilities (respectively Hilo, HI at Gemini North, and La Serena, Chile at Gemini South). BFO was identified as a key project for Gemini's transition program, as it created an opportunity to reduce operational costs. In November 2015, the Gemini North telescope started operating from the base facility in Hilo, Hawaii. In order to provide the remote operator the tools to work from the base, many of the activities that were normally performed by the night staff at the summit were replaced with new systems and tools. This paper describes some of the key systems and tools implemented for environmental monitoring, and the design used in the implementation at the Gemini North telescope.
GEMINI RENDEZVOUS EVALUATION POD (REP) - ARTIST CONCEPT
1965-08-01
S65-28653 (August 1965) --- Rendezvous Evaluation Pod (REP) in orbit is approached by Gemini spacecraft as seen in this artist's concept using an actual photograph taken on the Gemini-4 mission. The REP is superimposed over a Gemini-4 Earth-sky picture of cloud formations over an ocean. The REP will be used by the crew of the Gemini-5 spacecraft to practice rendezvous techniques.
The Gemini NICI Planet-Finding Campaign: The Companion Detection Pipeline
NASA Astrophysics Data System (ADS)
Wahhaj, Zahed; Liu, Michael C.; Biller, Beth A.; Nielsen, Eric L.; Close, Laird M.; Hayward, Thomas L.; Hartung, Markus; Chun, Mark; Ftaclas, Christ; Toomey, Douglas W.
2013-12-01
We present high-contrast image processing techniques used by the Gemini NICI Planet-Finding Campaign to detect faint companions to bright stars. The Near-Infrared Coronographic Imager (NICI) is an adaptive optics instrument installed on the 8 m Gemini South telescope, capable of angular and spectral difference imaging and specifically designed to image exoplanets. The Campaign data pipeline achieves median contrasts of 12.6 mag at 0.''5 and 14.4 mag at 1'' separation, for a sample of 45 stars (V = 4.3-13.9 mag) from the early phase of the campaign. We also present a novel approach to calculating contrast curves for companion detection based on 95% completeness in the recovery of artificial companions injected into the raw data, while accounting for the false-positive rate. We use this technique to select the image processing algorithms that are more successful at recovering faint simulated point sources. We compare our pipeline to the performance of the Locally Optimized Combination of Images (LOCI) algorithm for NICI data and do not find significant improvement with LOCI. Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the Science and Technology Facilities Council (United Kingdom), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), Ministério da Ciência e Tecnologia (Brazil) and Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina).
Gemini 7 backup crew seen in white room during Gemini 7 simulation activity
1965-11-27
S65-61837 (27 Nov. 1965) --- The Gemini-7 backup crew seen in the White Room atop Pad 19 during Gemini-7 simulation flight activity. McDonnell Aircraft Corporation technicians assist in the exercise. Astronaut Edward H. White II (in foreground) is the Gemini-7 backup crew command pilot; and astronaut Michael Collins (right background) is the backup crew pilot. Photo credit: NASA
NASA Technical Reports Server (NTRS)
Thomas, Kenneth S.
2016-01-01
Kenneth Thomas will discuss the Intra-Extra Vehicular Activity Russian & Gemini spacesuits. While the United States and Russia adapted to existing launch- and reentry-type suits to allow the first human ventures into the vacuum of space, there were differences in execution and capabilities. Mr. Thomas will discuss the advantages and disadvantages of this approach compared to exclusively intravehicular or extra-vehicular suit systems.
Characterizing Dusty Debris Disks with the Gemini Planet Imager
NASA Astrophysics Data System (ADS)
Chen, Christine; Arriaga, Pauline; Bruzzone, Sebastian; Choquet, Elodie; Debes, John H.; Donaldson, Jessica; Draper, Zachary; Duchene, Gaspard; Esposito, Thomas; Fitzgerald, Michael P.; Golimowski, David A.; Hines, Dean C.; Hinkley, Sasha; Hughes, A. Meredith; Kalas, Paul; Kolokolova, Ludmilla; Lawler, Samantha; Matthews, Brenda C.; Mazoyer, Johan; Metchev, Stanimir A.; Millar-Blanchaer, Max; Moro-Martin, Amaya; Nesvold, Erika; Padgett, Deborah; Patience, Jenny; Perrin, Marshall D.; Pueyo, Laurent; Rantakyro, Fredrik; Rodigas, Timothy; Schneider, Glenn; Soummer, Remi; Song, Inseok; Stark, Chris; Weinberger, Alycia J.; Wilner, David J.
2017-01-01
We have been awarded 87 hours of Gemini Observatory time to obtain multi-wavelength observations of HST resolved debris disks using the Gemini Planet Imager. We have executed ~51 hours of telescope time during the 2015B-2016B semesters observing 12 nearby, young debris disks. We have been using the GPI Spec and Pol modes to better constrain the properties of the circumstellar dust, specifically, measuring the near-infrared total intensity and polarization fraction colors, and searching for solid-state spectral features of nearby beta Pic-like disks. We expect that our observations will allow us to break the degeneracy among the particle properties such as composition, size, porosity, and shape. We present some early results from our observations.
Wang, Haitang; Wettig, Shawn D
2011-01-14
Improvements in transfection efficiency are required in order to make the goal of cellular gene delivery by non-viral vectors realizable. Novel derivatives of gemini surfactants having dissymmetric tail groups have been designed specifically as a means to improve DNA transfection; the micelle and interfacial properties are reported herein. The effect of these substitutions on the aggregation properties of the gemini surfactants is discussed in the context of results for the m-3-m gemini series, previously reported in the literature. Phytanyl substitution results in lower cmc and higher micelle ionization. In addition, the phytanyl substituted gemini surfactants form vesicles at room temperature. Preliminary in vitro transfection assays showed the phytanyl substituted gemini surfactants to be more efficient transfection vectors as compared to symmetric gemini surfactants.
NASA Astrophysics Data System (ADS)
Migahed, M. A.; elgendy, Amr.; EL-Rabiei, M. M.; Nady, H.; Zaki, E. G.
2018-05-01
Two new sequences of Gemini di-quaternary ammonium salts were synthesized characterized by FTIR and 1HNMR spectroscopic techniques and evaluated as corrosion inhibitor for X-65 steel dissolution in deep oil wells formation water saturated with CO2. The anti-corrosion performance of these compounds was studied by different electrochemical techniques i.e. (potentiodynamic polarization and AC impedance methods), Surface morphology (SEM and EDX) analysis and quantum chemical calculations. Results showed that the synthesized compounds were of mixed-type inhibitors and the inhibition capability was influenced by the inhibitor dose and the spacer substitution in their structure as indicated by Tafel plots. Surface active parameters were determined from the surface tension profile. The synthesized compounds adsorbed via Langmuir adsorption model with physiochemical adsorption as inferred from the standard free energy (ΔG°ads) values. Surface morphology (SEM and EDX) data for inhibitor (II) shows the development of adsorbed film on steel specimen. Finally, the experimental results were supported by the quantum chemical calculations using DFT theory.
Exploring a Massive Starburst in the Epoch of Reionization
NASA Astrophysics Data System (ADS)
Marrone, Daniel; Aravena, M.; Chapman, S.; De Breuck, C.; Gonzalez, A.; Hezavehe, S.; Litke, K.; Ma, J.; Malkan, M.; Spilker, J.; Stalder, B.; Stark, D.; Strandet, M.; Tang, M.; Vieira, J.; Weiss, A.; Welikala, N.
2016-08-01
We request deep multi-band imaging of a unique dusty galaxy in the Epoch of Reionization (EoR), selected via its millimeter-wavelength dust emission in the 2500-square-degree South Pole Telescope survey. Spectroscopically confirmed to lie at z=6.900, this galaxy has a large dust mass and is likely one of the most rapidly star-forming objects in the EoR. Using Gemini-S, we have identified z-band emission from this object that could be UV continuum emission at z=6.9 or from a foreground lens. Interpretation of this object, and a complete understanding of its meaning for the census of star formation in the EoR, requires that we establish the presence or absence of gravitational lensing. The dust mass observed in this source is also unexpectedly large for its era, and measurements of the assembled stellar population, through the UV-continuum slope and restframe optical color, will help characterize the stellar mass and dust properties in this very early galaxy, the most spectacular galaxy yet discovered by the SPT.
Commissioning of the new GMOS-N Hamamatsu CCDs
NASA Astrophysics Data System (ADS)
Scharwaechter, Julia; Chiboucas, Kristin; Gimeno, German; Boucher, Luc; White, John; Tapia, Eduardo; Lundquist, Michael; Rippa, Mathew; Labrie, Kathleen; Murowinski, Richard; Lazo, Manuel; Miller, Jennifer
2017-06-01
We report on the commissioning of the new Hamamatsu fully-depleted CCDs for GMOS-N, installed in the instrument in February 2017. The Hamamatsu detectors replace the e2v deep depletion devices which had been in operation since 2011. The new GMOS-N detector array is expected to provide improved red sensitivity compared to the e2v devices at wavelengths longer than ~900 nm. The commissioning of the new detector array for GMOS-N marks the final step in upgrading the two GMOS instruments at Gemini North and South with Hamamatsu detectors.
GEMINI- INSIGNIA - SPACE PROGRAM - MSC
1965-08-30
S65-54354 (30 Aug. 1965) --- The insignia of the Gemini Space Program is a disc of dark blue as a background for a gold Zodiac Gemini symbol. A white star on each of the two vertical curves of the Gemini symbol represent the Gemini twins, Pollux and Castor. The NASA insignia design for Gemini flights is reserved for use by the astronauts and for other official use as the NASA Administrator may authorize. Public availability has been approved only in the form of illustrations by the various news media. When and if there is any change in this policy, which we do not anticipate, it will be publicly announced.
NASA Astrophysics Data System (ADS)
Guérou, Adrien; Emsellem, Eric; McDermid, Richard M.; Côté, Patrick; Ferrarese, Laura; Blakeslee, John P.; Durrell, Patrick R.; MacArthur, Lauren A.; Peng, Eric W.; Cuillandre, Jean-Charles; Gwyn, Stephen
2015-05-01
We present Gemini Multi Object Spectrograph integral-field unit (GMOS-IFU) data of eight compact, low-mass early-type galaxies (ETGs) in the Virgo cluster. We analyze their stellar kinematics and stellar population and present two-dimensional maps of these properties covering the central 5″ × 7″ region. We find a large variety of kinematics, from nonrotating to highly rotating objects, often associated with underlying disky isophotes revealed by deep images from the Next Generation Virgo Cluster Survey. In half of our objects, we find a centrally concentrated younger and more metal-rich stellar population. We analyze the specific stellar angular momentum through the λR parameter and find six fast rotators and two slow rotators, one having a thin counterrotating disk. We compare the local galaxy density and stellar populations of our objects with those of 39 more extended low-mass Virgo ETGs from the SMAKCED survey and 260 massive (M > 1010 {{M}⊙ }) ETGs from the ATLAS3D sample. The compact low-mass ETGs in our sample are located in high-density regions, often close to a massive galaxy, and have, on average, older and more metal-rich stellar populations than less compact low-mass galaxies. We find that the stellar population parameters follow lines of constant velocity dispersion in the mass-size plane, smoothly extending the comparable trends found for massive ETGs. Our study supports a scenario where low-mass compact ETGs have experienced long-lived interactions with their environment, including ram-pressure stripping and gravitational tidal forces, that may be responsible for their compact nature.
Self-assembled Gemini surfactant film-mediated dispersion stability.
Rabinovich, Y I; Kanicky, J R; Pandey, S; Oskarsson, H; Holmberg, K; Moudgil, B M; Shah, D O
2005-08-15
The force-distance curves of 12-2-12 and 12-4-12 Gemini quaternary ammonium bromide surfactants on mica and silica surfaces obtained by atomic force microscopy (AFM) were correlated with the structure of the adsorption layer. The critical micelle concentration was measured in the presence or absence of electrolyte. The electrolyte effect (the decrease of CMC) is significantly more pronounced for Gemini than for single-chain surfactants. The maximum compressive force, F(max), of the adsorbed surfactant aggregates was determined. On the mica surface in the presence of 0.1 M NaCl, the Gemini micelles and strong repulsive barrier appear at surfactant concentrations 0.02-0.05 mM, which is significantly lower than that for the single C(12)TAB (5-10 mM). This difference between single and Gemini surfactants can be explained by a stronger adsorption energy of Gemini surfactants. The low concentration of Gemini at which this surfactant forms the strong micellar layer on the solid/solution interface proves that Gemini aggregates (micelles) potentially act as dispersing agent in processes such as chemical mechanical polishing or collector in flotation. The AFM force-distance results obtained for the Gemini surfactants were used along with turbidity measurements to determine how adsorption of Gemini surfactants affects dispersion stability. It has been shown that Gemini (or two-chain) surfactants are more effective dispersing agents, and that in the presence of electrolyte, the silica dispersion stability at pH 4.0 can also be achieved at very low surfactant concentrations ( approximately 0.02 mM).
Estudio fotométrico de candidatos a cúmulos globulares en NGC 1316
NASA Astrophysics Data System (ADS)
Sesto, L. A.; Faifer, F. R.; Forte, J. C.
We present the first results obtained in the context of a photometric study of the globular cluster population associated with the early-type giant galaxy NGC 1316. We analyze here the first of a total of ten fields that form a deep mosaic, which was obtained using the Gemini Multi-Object Spectrograph camera. This field contains the nucleus of the galaxy. As a result of psf photometry, we construct color-magnitude and color-color diagrams, as well as spatial distribution and integrated color diagrams. The analysis shows that there is no clear evidence of bimodality in the studied region. However, we confirm the presence of a probable young subpopulation of clusters in this system. Finally, we present color maps of the galaxy, showing the presence of an interesting structure produced by interstellar dust which is surrounding the nucleus of NGC 1316. Our results indicate that no significant effect is observed due to dust on the objects in the studied region. FULL TEXT IN SPANISH
NASA Astrophysics Data System (ADS)
Galicher, R.; Marois, C.; Macintosh, B.; Zuckerman, B.; Barman, T.; Konopacky, Q.; Song, I.; Patience, J.; Lafrenière, D.; Doyon, R.; Nielsen, E. L.
2016-10-01
Context. Radial velocity and transit methods are effective for the study of short orbital period exoplanets but they hardly probe objects at large separations for which direct imaging can be used. Aims: We carried out the international deep planet survey of 292 young nearby stars to search for giant exoplanets and determine their frequency. Methods: We developed a pipeline for a uniform processing of all the data that we have recorded with NIRC2/Keck II, NIRI/Gemini North, NICI/Gemini South, and NACO/VLT for 14 yr. The pipeline first applies cosmetic corrections and then reduces the speckle intensity to enhance the contrast in the images. Results: The main result of the international deep planet survey is the discovery of the HR 8799 exoplanets. We also detected 59 visual multiple systems including 16 new binary stars and 2 new triple stellar systems, as well as 2279 point-like sources. We used Monte Carlo simulations and the Bayesian theorem to determine that 1.05+2.80-0.70% of stars harbor at least one giant planet between 0.5 and 14 MJ and between 20 and 300 AU. This result is obtained assuming uniform distributions of planet masses and semi-major axes. If we consider power law distributions as measured for close-in planets instead, the derived frequency is 2.30+5.95-1.55%, recalling the strong impact of assumptions on Monte Carlo output distributions. We also find no evidence that the derived frequency depends on the mass of the hosting star, whereas it does for close-in planets. Conclusions: The international deep planet survey provides a database of confirmed background sources that may be useful for other exoplanet direct imaging surveys. It also puts new constraints on the number of stars with at least one giant planet reducing by a factor of two the frequencies derived by almost all previous works. Tables 11-15 are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/594/A63
Manned Space Flight Experiments Symposium: Gemini Missions III and IV
NASA Technical Reports Server (NTRS)
1965-01-01
This is a compilation of papers on in-flight experiments presented at the first symposium of a series, Manned Space Flight Experiments Symposium, sponsored by the National Aeronautics and Space Administration. The results of experiments conducted during the Gemini Missions III and IV are covered. These symposiums are to be conducted for the scientific community at regular intervals on the results of experiments carried out in conjunction with manned space flights.
Deep-inelastic multinucleon transfer processes in the 16O+27Al reaction
NASA Astrophysics Data System (ADS)
Roy, B. J.; Sawant, Y.; Patwari, P.; Santra, S.; Pal, A.; Kundu, A.; Chattopadhyay, D.; Jha, V.; Pandit, S. K.; Parkar, V. V.; Ramachandran, K.; Mahata, K.; Nayak, B. K.; Saxena, A.; Kailas, S.; Nag, T. N.; Sahoo, R. N.; Singh, P. P.; Sekizawa, K.
2018-03-01
The reaction mechanism of deep-inelastic multinucleon transfer processes in the 16O+27Al reaction at an incident 16O energy (Elab=134 MeV) substantially above the Coulomb barrier has been studied both experimentally and theoretically. Elastic-scattering angular distribution, total kinetic energy loss spectra, and angular distributions for various transfer channels have been measured. The Q -value- and angle-integrated isotope production cross sections have been deduced. To obtain deeper insight into the underlying reaction mechanism, we have carried out a detailed analysis based on the time-dependent Hartree-Fock (TDHF) theory. A recently developed method, TDHF+GEMINI, has been applied to evaluate production cross sections for secondary products. From a comparison between the experimental and theoretical cross sections, we find that the theory qualitatively reproduces the experimental data. Significant effects of secondary light-particle emissions are demonstrated. Possible interplay among fusion-fission, deep-inelastic, multinucleon transfer, and particle evaporation processes is discussed.
The opto-mechanical design for GMOX: a next-generation instrument concept for Gemini
NASA Astrophysics Data System (ADS)
Smee, Stephen A.; Barkhouser, Robert; Robberto, Massimo; Ninkov, Zoran; Gennaro, Mario; Heckman, Timothy M.
2016-08-01
We present the opto-mechanical design of GMOX, the Gemini Multi-Object eXtra-wide-band spectrograph, a potential next-generation (Gen-4 #3) facility-class instrument for Gemini. GMOX is a wide-band, multi-object, spectrograph with spectral coverage spanning 350 nm to 2.4 um with a nominal resolving power of R 5000. Through the use of Digital Micromirror Device (DMD) technology, GMOX will be able to acquire spectra from hundreds of sources simultaneously, offering unparalleled flexibility in target selection. Utilizing this technology, GMOX can rapidly adapt individual slits to either seeing-limited or diffraction-limited conditions. The optical design splits the bandpass into three arms, blue, red, and near infrared, with the near-infrared arm being split into three channels covering the Y+J band, H band, and K band. A slit viewing camera in each arm provides imaging capability for target acquisition and fast-feedback for adaptive optics control with either ALTAIR (Gemini North) or GeMS (Gemini South). Mounted at the Cassegrain focus, GMOX is a large (1.3 m x 2.8 m x 2.0 m) complex instrument, with six dichroics, three DMDs (one per arm), five science cameras, and three acquisition cameras. Roughly half of these optics, including one DMD, operate at cryogenic temperature. To maximize stiffness and simplify assembly and alignment, the opto-mechanics are divided into three main sub-assemblies, including a near-infrared cryostat, each having sub-benches to facilitate ease of alignment and testing of the optics. In this paper we present the conceptual opto-mechanical design of GMOX, with an emphasis on the mounting strategy for the optics and the thermal design details related to the near-infrared cryostat.
Gemini Observatory base facility operations: systems engineering process and lessons learned
NASA Astrophysics Data System (ADS)
Serio, Andrew; Cordova, Martin; Arriagada, Gustavo; Adamson, Andy; Close, Madeline; Coulson, Dolores; Nitta, Atsuko; Nunez, Arturo
2016-08-01
Gemini North Observatory successfully began nighttime remote operations from the Hilo Base Facility control room in November 2015. The implementation of the Gemini North Base Facility Operations (BFO) products was a great learning experience for many of our employees, including the author of this paper, the BFO Systems Engineer. In this paper we focus on the tailored Systems Engineering processes used for the project, the various software tools used in project support, and finally discuss the lessons learned from the Gemini North implementation. This experience and the lessons learned will be used both to aid our implementation of the Gemini South BFO in 2016, and in future technical projects at Gemini Observatory.
NASA Remembers Gemini, Apollo Astronaut Dick Gordon
2017-11-07
Astronaut Dick Gordon, command module pilot on Apollo 12, the second lunar landing mission, died on Monday, November 6 at the age of 88. A native of Seattle, Washington and 1951 graduate of the University of Washington, Gordon became an astronaut in 1963 after a career as a naval aviator. He spent more than 316 hours in space on two missions. He was the pilot for the three-day Gemini 11 mission in 1966 and performed two spacewalks. At the time of the flight, Gemini 11 set the world altitude record of 850 miles. Gordon made a second flight in 1969 as command pilot on Apollo 12 with spacecraft commander, Pete Conrad and lunar module pilot, Alan Bean. Throughout the 31-hour lunar surface stay by Conrad and Bean, Gordon remained in orbit around the moon on the command module, "Yankee Clipper." In November 2005, NASA honored Gordon with an Ambassador of Exploration award. NASA presented these prestigious awards to the astronauts who took part in the nation's Mercury, Gemini and Apollo space programs from 1961 to 1972.
Gemini-Titan (GT)-9 Test - Training - KSC
1966-06-10
S66-33406 (10 May 1966) --- Astronaut Thomas P. Stafford (on left), command pilot, and Eugene A. Cernan, pilot, in Gemini-9 spacecraft in the white room at Pad 19 during a Gemini-9/Agena simultaneous launch demonstration. This test is a coordinated dountdown of the Atlas-Agena and the Gemini-Titan vehicles. Photo credit: NASA
PRESS CONFERENCE - GEMINI-TITAN (GT)-11 - MSC
1966-08-01
S66-39895 (1 Aug. 1966) --- Panel members of the Gemini-10 news conference held in the Building 1 auditorium were (from left) Dr. Robert C. Seamans Jr., NASA Deputy Administrator; astronaut John W. Young, Gemini-10 command pilot; astronaut Michael Collins, Gemini-10 pilot; and Dr. Robert R. Gilruth, MSC Director. Photo credit: NASA
Adsorption of dissymmetric cationic gemini surfactants at silica/water interface
NASA Astrophysics Data System (ADS)
Sun, Yuhai; Feng, Yujun; Dong, Hongwei; Chen, Zhi
2007-05-01
Adsorption of a series of cationic gemini surfactants 12-2- m ( m = 8, 12, 16) on the surface of silica was investigated. The critical micelle concentrations, cmcs, of cationic gemini surfactants in the initial solutions and in the supernatants were measured by conductometry and tensiometer. The changes in cmc values indicate that the ion exchanges take place between polar groups of gemini surfactants adsorbed and ions bound on the surface of silica. The adsorption isotherms of cationic gemini surfactants were obtained by a solution depletion method. Based on the driving force, the adsorption includes two steps, one of which is ion exchange, and the other is hydrophobic interaction. In each step, the tendency of surfactant molecules in the solution to form aggregates or to be adsorbed on the silica varies with their structures. The maximum adsorption amount of gemini surfactants on the silica, τmax, decreases as increasing in the length of one alkyl chain, m, from 8, 12 to 16. So the results show that the adsorption behaviors of gemini surfactants are closely related to the dissymmetry of gemini molecules.
Wei, Jia; Li, Jun; Huang, Guohe; Wang, Xiujie; Chen, Guanghui; Zhao, Baihang
2016-09-01
A new generation of surfactant, Gemini surfactants, have been synthesized and have attracted the attention of various industrial and academic research groups. This study focused on the use of symmetric and dissymmetric quaternary ammonium Gemini surfactants to immobilize naphthalene onto soil particles, and is used as an example of an innovative application to remove HOC in situ using the surfactant-enhanced sorption zone. The sorption capacity of modified soils by Gemini surfactant and natural soils was compared and the naphthalene sorption efficiency, in the absence and presence of Gemini surfactants with different alkyl chain lengths, was investigated in the soil-water system. The results have shown that the increased added Gemini surfactant formed admicelles at the interface of soil/water having superior capability to retard contaminant. Symmetric and dissymmetric Gemini surfactants have opposite effect on the aspect of removing of PAH attributing to their solubilization and sorption behavior in soil-water system. Compared with the natural soil, sorption of naphthalene by Gemini-modified soil is noticeably enhanced following the order of C12-2-16 < C12-2-12 < C12-2-8. However, the symmetric Gemini surfactant C12-2-12 is the optimized one for in situ barrier remediation, which is not only has relative high retention ability but also low dosage.
The Swift GRB Host Galaxy Legacy Survey
NASA Astrophysics Data System (ADS)
Perley, Daniel A.
2015-01-01
I introduce the Swift Host Galaxy Legacy Survey (SHOALS), a comprehensive multiwavelength program to characterize the demographics of the GRB host population across its entire redshift range. Using unbiased selection criteria we have designated a subset of 130 Swift gamma-ray bursts which are now being targeted with intensive observational follow-up. Deep Spitzer imaging of every field has already been obtained and analyzed, with major programs ongoing at Keck, GTC, and Gemini to obtain complementary optical/NIR photometry to enable full SED modeling and derivation of fundamental physical parameters such as mass, extinction, and star-formation rate. Using these data I will present an unbiased measurement of the GRB host-galaxy luminosity and mass functions and their evolution with redshift between z=0 and z=5, compare GRB hosts to other star-forming galaxy populations, and discuss implications for the nature of the GRB progenitor and the ability of GRBs to probe cosmic star-formation.
The first optical spectra of Wolf-Rayet stars in M101 revealed with Gemini/GMOS
NASA Astrophysics Data System (ADS)
Pledger, J. L.; Shara, M. M.; Wilde, M.; Crowther, P. A.; Long, K. S.; Zurek, D.; Moffat, A. F. J.
2018-01-01
Deep narrow-band Hubble Space Telescope (HST) imaging of the iconic spiral galaxy M101 has revealed over a thousand new Wolf-Rayet (WR) candidates. We report spectrographic confirmation of 10 He II-emission line sources hosting 15 WR stars. We find WR stars present at both sub- and super-solar metallicities with WC stars favouring more metal-rich regions compared to WN stars. We investigate the association of WR stars with H II regions using archival HST imaging and conclude that the majority of WR stars are in or associated with H II regions. Of the 10 emission lines sources, only one appears to be unassociated with a star-forming region. Our spectroscopic survey provides confidence that our narrow-band photometric candidates are in fact bona fide WR stars, which will allow us to characterize the progenitors of any core-collapse supernovae that erupt in the future in M101.
Confirmation of 5 SN in the Kepler/K2 C16 Field with Gemini
NASA Astrophysics Data System (ADS)
Margheim, S.; Tucker, B. E.; Garnavich, P. M.; Rest, A.; Narayan, G.; Smith, K. W.; Smartt, S.; Kasen, D.; Shaya, E.; Mushotzky, R.; Olling, R.; Villar, A.; Forster, F.; Zenteno, A.; James, D.; Smith, R. Chris
2018-01-01
We report new spectroscopic classifications by KEGS of supernova discovered by Pan-STARRS1 during a targeted search of the Kepler/K2 Campaign 16 field using the Gemini Multi-Object Spectrograph (GMOS) on both the Gemini North Observatory on Mauna Kea, and the Gemini South Observatory on Cerro Pachon.
GEMINI-TITAN (GT)-9 PREFLIGHT ACTIVITY - ASTRONAUT THOMAS P. STAFFORD - MISC. - KSC
1969-01-21
S66-32044 (17 May 1966) --- Astronauts Eugene A. Cernan (left), pilot, and Thomas P. Stafford, command pilot, discuss the postponed Gemini-9 mission just after egressing their spacecraft in the white room atop Pad 19. The Agena Target Vehicle failed to achieve orbit, causing a termination of the mission. The spaceflight (to be called Gemini-9A) has been rescheduled for May 31. A Gemini Augmented Target Docking Adapter will be used as the rendezvous and docking vehicle for the Gemini-9 spacecraft. Photo credit: NASA
PRELAUNCH ACTIVITY (GT-6) - ASTRONAUT THOMAS P. STAFFORD - MISC.
1965-12-15
S65-61806 (15 Dec. 1965) --- Astronaut Thomas P. Stafford, Gemini-6 prime crew pilot, is seen through spacecraft window as he awaits the remaining minutes of the Gemini-6 prelaunch countdown. A two-day mission in space was scheduled for astronauts Stafford and Walter M. Schirra Jr. (out of frame), command pilot. NASA successfully launched Gemini-6 from Pad 19 at 8:37 a.m. (EST) on Dec. 15, 1965. An attempt will be made to rendezvous Gemini-6 with Gemini-7. Photo credit: NASA or National Aeronautics and Space Administration
GEMINI-TITAN-8 - PRELAUNCH ACTIVITY
1966-03-16
S66-24439 (16 March 1966) --- The Gemini-8 prime crew, along with several fellow astronauts, have a hearty breakfast of steak and eggs on the morning of the Gemini-8 launch. Seated clockwise around the table, starting at lower left, are Donald K. Slayton, Manned Spaceflight Center (MSC) Assistant Director for Flight Crew Operations; astronaut Neil A. Armstrong, Gemini-8 command pilot; scientist-astronaut F. Curtis Michel; astronaut R. Walter Cunningham; astronaut Alan B. Shepard Jr. (face obscured), Chief, MSC Astronaut Office; astronaut David R. Scott, Gemini-8 pilot; and astronaut Roger B. Chaffee. Photo credit: NASA
VizieR Online Data Catalog: The Gemini Observation Log (CADC, 2001-)
NASA Astrophysics Data System (ADS)
Association of Universities For Research in Astronomy
2018-01-01
This database contains a log of the Gemini Telescope observations since 2001, managed by the Canadian Astronomical Data Center (CADC). The data are regularly updated (see the date of the last version at the end of this file). The Gemini Observatory consists of twin 8.1-meter diameter optical/infrared telescopes located on two of the best observing sites on the planet. From their locations on mountains in Hawai'i and Chile, Gemini Observatory's telescopes can collectively access the entire sky. Gemini is operated by a partnership of five countries including the United States, Canada, Brazil, Argentina and Chile. Any astronomer in these countries can apply for time on Gemini, which is allocated in proportion to each partner's financial stake. (1 data file).
Host Galaxies of Luminous Type 2 Quasars at z ~ 0.5
NASA Astrophysics Data System (ADS)
Liu, Xin; Zakamska, Nadia L.; Greene, Jenny E.; Strauss, Michael A.; Krolik, Julian H.; Heckman, Timothy M.
2009-09-01
We present deep Gemini GMOS optical spectroscopy of nine luminous quasars at redshifts z ~ 0.5, drawn from the Sloan Digital Sky Survey type 2 quasar sample. Our targets were selected to have high intrinsic luminosities (MV < -26 mag) as indicated by the [O III] λ5007 Å emission-line luminosity (L [O III]). Our sample has a median black hole mass of ~108.8 M sun inferred assuming the local M BH-σ* relation and a median Eddington ratio of ~0.7, using stellar velocity dispersions σ* measured from the G band. We estimate the contamination of the stellar continuum from scattered quasar light based on the strength of broad Hβ, and provide an empirical calibration of the contamination as a function of L [O III]; the scattered-light fraction is ~30% of L 5100 for objects with L [O III] = 109.5 L sun. Population synthesis indicates that young poststarburst populations (<0.1 Gyr) are prevalent in luminous type 2 quasars, in addition to a relatively old population (>1 Gyr) which dominates the stellar mass. Broad emission complexes around He II λ4686 Å with luminosities up to 108.3 L sun are unambiguously detected in three out of the nine targets, indicative of Wolf-Rayet (WR) populations. Population synthesis shows that ~5 Myr poststarburst populations contribute substantially to the luminosities (>50% of L 5100) of all three objects with WR detections. We find two objects with double cores and four with close companions. Our results may suggest that luminous type 2 quasars trace an early stage of galaxy interaction, perhaps responsible for both the quasar and the starburst activity. Based, in part, on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the Science and Technology Facilities Council (United Kingdom), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), Ministério da Ciência e Tecnologia (Brazil), and Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina).
Astronauts Grissom and Young in Gemini Mission Simulator
1964-05-22
S64-25295 (March 1964) --- Astronauts Virgil I. (Gus) Grissom (right) and John W. Young, prime crew for the first manned Gemini mission (GT-3), are shown inside a Gemini mission simulator at McDonnell Aircraft Corp., St. Louis, MO. The simulator will provide Gemini astronauts and ground crews with realistic mission simulation during intensive training prior to actual launch.
GEMINI-TITAN (GT)-12 - EXTRAVEHICULAR (EVA) - MICROMETEOROID PACKAGE - OUTER SPACE
1966-11-11
S66-63538 (11 Nov. 1966) --- Astronaut Edwin E. Aldrin Jr., pilot for the Gemini-12 spaceflight, removes micrometeoroid package for return to the spacecraft during extravehicular activity (EVA) on the first day of the four-day mission. Command pilot for the Gemini-12 mission, the last in the Gemini series, was astronaut James A. Lovell Jr. Photo credit: NASA
DOE Office of Scientific and Technical Information (OSTI.GOV)
Horch, Elliott P.; Howell, Steve B.; Everett, Mark E.
2012-12-01
We present the results of 71 speckle observations of binary and unresolved stars, most of which were observed with the DSSI speckle camera at the Gemini North Telescope in 2012 July. The main purpose of the run was to obtain diffraction-limited images of high-priority targets for the Kepler and CoRoT missions, but in addition, we observed a number of close binary stars where the resolution limit of Gemini was used to better determine orbital parameters and/or confirm results obtained at or below the diffraction limit of smaller telescopes. Five new binaries and one triple system were discovered, and first orbitsmore » are calculated for other two systems. Several systems are discussed in detail.« less
Gemini 10 prime crew during post flight press conference
NASA Technical Reports Server (NTRS)
1966-01-01
At podium during Gemini 10 press conference are (l-r) Dr. Robert C. Seamans, Astronauts John Young and Michael Collins and Dr. Robert R. Gilruth (39895); Wide angle view of the Manned Spacecraft Center (MSC) News Center during the Gemini 10 prime crew post flight press conference (38786); Astronaut Young draws diagram on chalk board of tethered extravehicular activity accomplished during Gemini 10 flight (39897).
NASA Astrophysics Data System (ADS)
Aganze, Christian; Burgasser, Adam J.; Martin, Eduardo; Konopacky, Quinn; Masters, Daniel C.
2016-06-01
The majority of ultracool dwarf stars and brown dwarfs currently known were identified in wide-field red optical and infrared surveys, enabling measures of the local, typically isolated, population in a relatively shallow (<100 pc radius) volume. Constraining the properties of the wider Galactic population (scale height, radial distribution, Population II sources), and close brown dwarf and exoplanet companions to nearby stars, requires specialized instrumentation, such as high-contrast, coronagraphic spectrometers (e.g., Gemini/GPI, VLT/Sphere, Project 1640); and deep spectral surveys (e.g., HST/WFC3 parallel fields, Euclid). We present a set of quantitative methodologies to identify and robustly characterize sources for these specific populations, based on templates and tools developed as part of the SpeX Prism Library Analysis Toolkit. In particular, we define and characterize specifically-tuned sets spectral indices that optimize selection of cool dwarfs and distinguish rare populations (subdwarfs, young planetary-mass objects) based on low-resolution, limited-wavelength-coverage spectral data; and present a template-matching classification method for these instruments. We apply these techniques to HST/WFC3 parallel fields data in the WISPS and HST-3D programs, where our spectral index set allows high completeness and low contamination for searches of late M, L and T dwarfs to distances out to ~3 kpc.The material presented here is based on work supported by the National Aeronautics and Space Administration under Grant No. NNX15AI75G.
Gemini Model in the 10- by 10-Foot Supersonic Wind Tunnel
1962-09-21
A researcher at the National Aeronautics and Space Administration (NASA) Lewis Research Center examines a small-scale model of the Gemini capsule in the 10- by 10-Foot Supersonic Wind Tunnel test section. Gemini was added to NASA’s manned space program after its predecessor, Mercury, and its antecedent, Apollo, were already established. Gemini was a transitional mission designed provide the astronauts with practice docking with other spacecraft and withstanding durations in space up to two weeks. The program was officially announced on December 7, 1961, but planning began in mid-1959. It was named Gemini after the zodiac twins because of the spacecraft’s two passenger capacity. The Gemini Program was the first program to start at the new Manned Spacecraft Center in Houston, now the Johnson Space Center. Unlike Mercury and Apollo, Lewis had very little involvement with the Gemini Program. This model was tested in the 10- by 10 tunnel for several weeks in September 1962. Lewis began managing the Agena second-stage rocket program shortly after this photograph was taken. Agenas were used to launch a variety of spacecraft and satellites in the 1960s. They were also used on several Gemini missions to provide targets for the astronauts to practice their rendezvous maneuvers. Gemini had two unmanned and ten manned flights in 1965 and 1966. These yielded the first spacewalks, long-duration space missions, first onboard computer, docking with a second spacecraft, and rendezvous maneuvers.
Computer vision applications for coronagraphic optical alignment and image processing.
Savransky, Dmitry; Thomas, Sandrine J; Poyneer, Lisa A; Macintosh, Bruce A
2013-05-10
Modern coronagraphic systems require very precise alignment between optical components and can benefit greatly from automated image processing. We discuss three techniques commonly employed in the fields of computer vision and image analysis as applied to the Gemini Planet Imager, a new facility instrument for the Gemini South Observatory. We describe how feature extraction and clustering methods can be used to aid in automated system alignment tasks, and also present a search algorithm for finding regular features in science images used for calibration and data processing. Along with discussions of each technique, we present our specific implementation and show results of each one in operation.
A Virtual Field Trip to the Gemini Observatory
NASA Astrophysics Data System (ADS)
Fisher, R. Scott; Michaud, P. D.
2010-01-01
Live from Gemini (LfG) is a virtual field trip using video conferencing technology to connect primary, secondary and post-secondary students with scientists and educators at the Gemini Observatory. As a pilot project, LfG is rapidly becoming one of the observatory's most often-requested educational programs for learners of all ages. The program aligns exceptionally well with national science (and technology) standards, as well as existing school curricula. This combination makes it easy for teachers to justify participation in the program, especially as the necessary video conferencing technology becomes ever more ubiquitous in classrooms and technology learning centers around the world. In developing and testing this pilot project, a programmatic approach and philosophy evolved that includes post-field-trip educational materials, multi-disciplinary subject matter (astronomy, geology, mathematics, meteorology, engineering and even language - the program is offered in Spanish from Gemini South in Chile), and the establishment of a personal connection and rapport with students. The presenters work to create a comfortable interaction despite the perceived technological barriers. The authors’ experiences with the LfG pilot project convince us that this model is viable for almost any astronomical observatory and should be considered by any dynamic, technology- and education-oriented facility.
The Transformation of Observatory Newsletters - A Gemini Perspective
NASA Astrophysics Data System (ADS)
Zhang, Xiaoyu
2015-08-01
Astronomical observatories publish newsletters to communicate the observatory’s new discoveries and activities with its user communities, funding agencies, and general public. Gemini Observatory started publishing the newsletter in March 1992. Over the years, it transformed from a no-frills black and white publication to a full-color magazine type newsletter with a special name “GeminiFocus”. Since 2012, the contents of GeminiFocus moved from print to digital with an additional print issue of the Year in Review. The newsletter transformation is in sync with the rapid development of the internet technologies. We discuss here the evolvement of Gemini newsletter and the lessons learned.
Gemini-IFU Spectroscopy of HH 111
NASA Astrophysics Data System (ADS)
Cerqueira, A. H.; Vasconcelos, M. J.; Raga, A. C.; Feitosa, J.; Plana, H.
2015-03-01
We present new optical observations of the Herbig-Haro (HH) 111 jet using the Gemini Multi Object Spectrograph in its Integral Field Unit mode. Eight fields of 5\\prime\\prime × 3\\buildrel{\\prime\\prime}\\over{.} 5 have been positioned along and across the HH 111 jet, covering the spatial region from knot E to L in HH 111 (namely, knots E, F, G, H, J, K, and L). We present images and velocity channel maps for the [O i] 6300+6360, Hα, [N ii] 6548+6583, and [S ii] 6716+6730 lines, as well as for the [S ii] 6716/6730 line ratio. We find that the HH 111 jet has an inner region with lower excitation and higher radial velocity, surrounded by a broader region of higher excitation and lower radial velocity. Also, we find higher electron densities at lower radial velocities. These results imply that the HH 111 jet has a fast, axial region with lower velocity shocks surrounded by a lower velocity sheath with higher velocity shocks. Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the Science and Technology Facilities Council (United Kingdom), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), Ministério da Ciência, Tecnologia e Inovação (Brazil), and Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina).
Splashdown - Gemini-Titan (GT-12) Spacecraft - Mission Close - Atlantic
1966-11-15
S66-59986 (15 Nov. 1966) --- The Gemini spaceflight program concludes as the Gemini-12 spacecraft, with astronaut James A. Lovell Jr., command pilot, and Edwin E. Aldrin Jr., pilot, aboard, nears touchdown in the Atlantic Ocean 2.5 nautical miles from the prime recovery ship, USS Wasp. Gemini-12 splashed down at 2:21 p.m. (EST), Nov. 11, 1966, to conclude the four-day mission in space. Photo credit: NASA
Gemini-Titan (GT)-8 - Lightweight Suit - MSC
1965-12-06
S65-60035 (6 Dec. 1965) --- The new light-weight spacesuit planned for possible use during the Gemini-7 mission is modeled by Fred R. Spross, Gemini Support Office, Crew Systems Division. The spacesuit weighs 16 pounds, including the aviator's crash helmet. The suit is designed so that it may be partially or completely removed during flight. It has two layers of material while the previously used Gemini spacesuit has four layers. Photo credit: NASA
1966-06-06
S66-37972 (3 June 1966) ?-- The Augmented Target Docking Adapter (ATDA) is photographed from the Gemini-9 spacecraft during one of three rendezvous occasions in space. The ATDA and Gemini-9 spacecraft are 35.5 feet apart in this view. Failure of the docking adapter protective cover on the ATDA to fully separate prevented the docking of the two spacecraft. The ATDA was described by the Gemini-9 crew members as an ?angry alligator.? Photo credit: NASA
Gemini surfactants mediate efficient mitochondrial gene delivery and expression.
Cardoso, Ana M; Morais, Catarina M; Cruz, A Rita; Cardoso, Ana L; Silva, Sandra G; do Vale, M Luísa; Marques, Eduardo F; Pedroso de Lima, Maria C; Jurado, Amália S
2015-03-02
Gene delivery targeting mitochondria has the potential to transform the therapeutic landscape of mitochondrial genetic diseases. Taking advantage of the nonuniversal genetic code used by mitochondria, a plasmid DNA construct able to be specifically expressed in these organelles was designed by including a codon, which codes for an amino acid only if read by the mitochondrial ribosomes. In the present work, gemini surfactants were shown to successfully deliver plasmid DNA to mitochondria. Gemini surfactant-based DNA complexes were taken up by cells through a variety of routes, including endocytic pathways, and showed propensity for inducing membrane destabilization under acidic conditions, thus facilitating cytoplasmic release of DNA. Furthermore, the complexes interacted extensively with lipid membrane models mimicking the composition of the mitochondrial membrane, which predicts a favored interaction of the complexes with mitochondria in the intracellular environment. This work unravels new possibilities for gene therapy toward mitochondrial diseases.
Tracing the assembly history of NGC 1395 through its Globular Cluster System
NASA Astrophysics Data System (ADS)
Escudero, Carlos G.; Faifer, Favio R.; Smith Castelli, Analía V.; Forte, Juan C.; Sesto, Leandro A.; González, Nélida M.; Scalia, María C.
2018-03-01
We used deep Gemini-South/GMOS g΄r΄i΄z΄ images to study the globular cluster (GC) system of the massive elliptical galaxy NGC 1395, located in the Eridanus supergroup. The photometric analysis of the GC candidates reveals a clear colour bimodality distribution, indicating the presence of `blue' and `red' GC subpopulations. While a negative radial colour gradient is detected in the projected spatial distribution of the red GCs, the blue GCs display a shallow colour gradient. The blue GCs also display a remarkable shallow and extended surface density profile, suggesting a significant accretion of low-mass satellites in the outer halo of the galaxy. In addition, the slope of the projected spatial distribution of the blue GCs in the outer regions of the galaxy, is similar to that of the X-ray halo emission. Integrating up to 165 kpc the profile of the projected spatial distribution of the GCs, we estimated a total GC population and specific frequency of 6000 ± 1100 and SN = 7.4 ± 1.4, respectively. Regarding NGC 1395 itself, the analysis of the deep Gemini/GMOS images shows a low surface brightness umbrella-like structure indicating, at least, one recent merger event. Through relations recently published in the literature, we obtained global parameters, such as Mstellar = 9.32 × 1011 M⊙ and Mh = 6.46 × 1013 M⊙. Using public spectroscopic data, we derive stellar population parameters of the central region of the galaxy by the full spectral fitting technique. We have found that this region seems to be dominated for an old stellar population, in contrast to findings of young stellar populations from the literature.
GORDON, RICHARD F., ASTRONAUT - MISC. - GEMINI-TITAN (GT)-XI - RECOVERY - FROGMEN - ATLANTIC
1966-09-15
S66-50759 (15 Sept. 1966) --- Astronaut Richard F. Gordon Jr., pilot of the Gemini-11 spaceflight, is hoisted from the water by a recovery helicopter from the prime recovery ship USS Guam. Gemini-11 splashed down in the western Atlantic recovery area at 9 a.m. (EST), Sept. 15, 1966, to conclude the three-day mission in space. Astronaut Charles Conrad Jr. (out of frame) is the Gemini-11 command pilot. Photo credit: NASA
Docking - Gemini-Titan (GT)-11 - Outer Space
1966-09-14
S66-54555 (14 Sept. 1966) --- The Gemini-11 spacecraft is docked to the Agena Target Vehicle in this photograph taken by astronaut Richard F. Gordon Jr., pilot, as he stood in the open hatch of the Gemini-11 spacecraft during his extravehicular activity (EVA). Note Agena's L-band antenna. Taken during Gemini-11's 29th revolution of Earth, using a modified 70mm Hasselblad camera, with Eastman Kodak, Ektachrome, MS (S.O. 368) color film. Photo credit: NASA
GEMINI-TITAN (GT)-9 - EARTH-SKY - AUGMENTED TARGET DOCKING ADAPTER (ATDA) - MSC
1966-06-06
S66-37923 (3 June 1966) --- The Augmented Target Docking Adapter (ATDA) as seen from the Gemini-9 spacecraft during one of their three rendezvous in space. The ATDA and Gemini-9 spacecraft are 66.5 feet apart. Failure of the docking adapter protective cover to fully separate on the ATDA prevented the docking of the two spacecraft. The ATDA was described by the Gemini-9 crew as an "angry alligator." Photo credit: NASA
1966-06-06
S66-37943 (3 June 1966) --- The Augmented Target Docking Adapter is photographed against the background of the blackness of space from the Gemini-9 spacecraft during one of their three rendezvous in space. The ATDA and Gemini-9 spacecraft are 71.5 feet apart. Failure of the docking adapter protective cover to fully separate on the ATDA prevented the docking of the two spacecraft. The ATDA was described by the Gemini-9 crew as an ?Angry Alligator.? Photo credit: NASA
PRESS CONFERENCE - PUBLIC AFFAIRS OFFICE (PAO) - GEMINI-TITAN (GT) IX-A
1966-06-17
S66-39446 (17 June 1966) --- Movie film of the Gemini-9A and Augmented Target Docking Adapter rendezvous was shown at the Gemini-9A press conference in the MSC auditorium. Astronauts Thomas P. Stafford (left) and Eugene A. Cernan discussed the Gemini-9A/ATDA rendezvous mission during the film. Pictured on the screen, shows a close-up of the ATDA, described by the astronauts as an "angry alligator." Photo credit: NASA
Photometric Calibration of the Gemini South Adaptive Optics Imager
NASA Astrophysics Data System (ADS)
Stevenson, Sarah Anne; Rodrigo Carrasco Damele, Eleazar; Thomas-Osip, Joanna
2017-01-01
The Gemini South Adaptive Optics Imager (GSAOI) is an instrument available on the Gemini South telescope at Cerro Pachon, Chile, utilizing the Gemini Multi-Conjugate Adaptive Optics System (GeMS). In order to allow users to easily perform photometry with this instrument and to monitor any changes in the instrument in the future, we seek to set up a process for performing photometric calibration with standard star observations taken across the time of the instrument’s operation. We construct a Python-based pipeline that includes IRAF wrappers for reduction and combines the AstroPy photutils package and original Python scripts with the IRAF apphot and photcal packages to carry out photometry and linear regression fitting. Using the pipeline, we examine standard star observations made with GSAOI on 68 nights between 2013 and 2015 in order to determine the nightly photometric zero points in the J, H, Kshort, and K bands. This work is based on observations obtained at the Gemini Observatory, processed using the Gemini IRAF and gemini_python packages, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the National Research Council (Canada), CONICYT (Chile), Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina), and Ministério da Ciência, Tecnologia e Inovação (Brazil).
Astronaut Virgil Grissom shown through window of open hatch on Gemini craft
NASA Technical Reports Server (NTRS)
1965-01-01
Astronaut Virgil I. Grissom, the command pilot of the Gemini-Titan 3 three orbit mission, is shown through the window of the open hatch on Gemini spacecraft in the white room on the mornining of the launch.
Observations Of The LCROSS Impact With NIFS On The Gemini North Telescope
NASA Astrophysics Data System (ADS)
Roth, Katherine; Stephens, A. W.; Trujillo, C. A.; McDermid, R. M.; Woodward, C. E.; Walls, B. D.; Coulson, D. M.; Matulonis, A. C.; Ball, J. G.; Wooden, D. H.
2010-01-01
The Lunar CRater Observation and Sensing Satellite (LCROSS) Centaur rocket impacted a permanently shadowed crater near the south pole of the Moon at 11:31 UTC 2009 October 09. Gemini, one of several telescopes in a coordinated network observing the impact, conducted observations using NIFS to obtain 3D K-band imaging spectroscopy to detect water ice in the ejected plume of material. The spectral slope of the NIFS data can constrain the grain size and height distribution as the plume evolves, measuring the total mass and the water ice concentration in the plume. These observations provided an engineering challenge for Gemini, including the need to track non-sidereal with constantly changing track rates and guide on small bright moon craters, in order to keep the impact site within the NIFS field-of-view. High quality images taken by GMOS-N, NIRI and the acquisition camera during engineering periods at specific lunar libration and illumination were also used by the LCROSS ground based observing team to supplement slit positioning and offset plans for other ground based observatories. LCROSS mission support and engineering has resulted in improved telescope functionality for non-sidereal targets, including the ability to upload and import target ephemerides directly into the TCS, starting in semester 2010B. In this poster we present the engineering results and observing improvements which will facilitate enhanced user capabilities of the Gemini telescopes arising from the intensive LCROSS support challenge. Gemini Observatory is operated by AURA, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the NSF (United States), the STFC (United Kingdom), the NRC (Canada), CONICYT (Chile), the ARC (Australia), Ministério da Ciência e Tecnologia (Brazil), and Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina). In part this research was supported by NASA through contracts to SWRI and NSF grant AST-0706980 to the U. Minnesota.
GEMINI: Integrative Exploration of Genetic Variation and Genome Annotations
Paila, Umadevi; Chapman, Brad A.; Kirchner, Rory; Quinlan, Aaron R.
2013-01-01
Modern DNA sequencing technologies enable geneticists to rapidly identify genetic variation among many human genomes. However, isolating the minority of variants underlying disease remains an important, yet formidable challenge for medical genetics. We have developed GEMINI (GEnome MINIng), a flexible software package for exploring all forms of human genetic variation. Unlike existing tools, GEMINI integrates genetic variation with a diverse and adaptable set of genome annotations (e.g., dbSNP, ENCODE, UCSC, ClinVar, KEGG) into a unified database to facilitate interpretation and data exploration. Whereas other methods provide an inflexible set of variant filters or prioritization methods, GEMINI allows researchers to compose complex queries based on sample genotypes, inheritance patterns, and both pre-installed and custom genome annotations. GEMINI also provides methods for ad hoc queries and data exploration, a simple programming interface for custom analyses that leverage the underlying database, and both command line and graphical tools for common analyses. We demonstrate GEMINI's utility for exploring variation in personal genomes and family based genetic studies, and illustrate its ability to scale to studies involving thousands of human samples. GEMINI is designed for reproducibility and flexibility and our goal is to provide researchers with a standard framework for medical genomics. PMID:23874191
View of the nose of the Gemini 9 spacecraft taken from hatch of spacecraft
NASA Technical Reports Server (NTRS)
1966-01-01
Astronaut Eugene A. Cernan, pilot of the Gemini 9-A space flight, took this picture of the nose of the Gemini 9 spacecraft while standing in hatch of spacecraft. Area of earth below is the Pacific Ocean.
Gemini 9 spacecraft during EVA as seen Astronaut Eugene Cernan
NASA Technical Reports Server (NTRS)
1966-01-01
Astronaut Eugene A. Cernan took this view of the Gemini 9 spacecraft and his umbilical cord (right) over California, Arizona, and Sonora, Mexico, during his extravehicular activity on the Gemini 9 mission. Taken during the 32nd revolution of the flight.
GEMINI-TITAN (GT)-10 (RECOVERY)- ASTRONAUT JOHN W. YOUNG - MISC. - ATLANTIC
1966-07-21
S66-42787 (21 July 1966) --- Twelve-year -old Billy Doyle of Virginia Beach, VA., shakes hands with astronaut Michael Collins, Gemini-10 pilot, aboard the recovery ship USS Guadalcanal. At right is John W. Young, command pilot of the Gemini-10 spaceflight. Billy represented 41 youngsters permitted aboard the Guadalcanal to witness the recovery with their Naval fathers or close relatives, marking the first time dependents have been permitted aboard a ship during a Gemini recovery operation. Photo credit: NASA
MISSION CONTROL CENTER (MCC) - GEMINI-TITAN (GT)-6 ACTIVITY - MSC
1965-12-12
S65-62062 (12 Dec. 1965) --- Discussing the scrubbing of the planned National Aeronautics and Space Administration?s Gemini-6 spaceflight are (from left) William C. Schneider (standing), deputy director, Gemini Program Office of Manned Spaceflight, NASA Headquarters, Washington, D.C.; Eugene F. Kranz (seated), white team flight director; Christopher C. Kraft Jr., red team flight director; and John D. Hodge, blue team flight director. The Gemini-6 mission has been rescheduled for Dec. 15, 1965. Photo credit: NASA or National Aeronautics and Space Administration
Gemini 6 prime crew in white room atop Pad 19 during Gemini 6 countdown
NASA Technical Reports Server (NTRS)
1965-01-01
NASA and McDonnell technicians assist the Gemini 6 prime crew into the spacecraft in the White Room atop Pad 19 during the Gemini 6 prelaunch countdown. Astronaut Walter M. Schirra Jr., command pilot, is on left; and Astronaut Thomas P. Stafford, is on the right. Between the two is a note attached to the capsule which reads 'Good Luck from 2nd Shift'. Liftoff was at 8:37 a.m., December 15, 1965.
1965-12-04
S65-59934 (4 Dec. 1965) --- Gemini-7 pilot James A. Lovell Jr. has a temperature check with an oral temperature probe attached to his spacesuit during a final preflight preparations for the Gemini-7 space mission. The National Aeronautics and Space Administration has planned a 14-day mission for the Gemini-7. The temperature probe allows doctors to monitor astronauts' body temperature at any time during the mission. Photo credit: NASA
Gemini 7 prime crew during suiting up procedures at Launch Complex 16
NASA Technical Reports Server (NTRS)
1965-01-01
Astronaut James A. Lovell Jr. (left), Gemini 7 prime crew pilot, talks with NASA space suit technician Clyde Teague during suiting up procedures at Launch Complex 16, Kennedy Space Center. Lovell wears the new lightweight space suit planned for use during the Gemini 7 mission (61756); Astronaut Frank Borman, comand pilot of the Gemini 7 space flight, undergoes suiting up operations in Launch Complex 16 during prelaunch countdown. Medical biosensors are attached to his scalp (61757).
Astronaut Eugene Cernan sits in Gemini boilerplate during water egress
1966-04-09
S66-29559 (9 April 1966) --- Astronaut Eugene A. Cernan, prime crew pilot of the National Aeronautics and Space Administration?s Gemini-9 spaceflight, sits in Gemini Boiler-plate during water egress training activity in the Gulf of Mexico. Photo credit: NASA
Singh, Jagbir; Michel, Deborah; Getson, Heather M; Chitanda, Jackson M; Verrall, Ronald E; Badea, Ildiko
2015-02-01
Recently, we synthesized amino acid- and peptide-substituted gemini surfactants, 'biolipids' that exhibited high transfection efficiency in vitro. In this study, we developed these plasmid DNA and gemini surfactant lipid particles for noninvasive administration in vaginal cavity. Novel formulations of these gene delivery systems were prepared with poloxamer 407 to induce in situ gelling of the formulation and diethylene glycol monoethyl ether to improve their penetration across mucosal tissue. Poloxamer at 16% w/v concentration in diethylene glycol monoethyl ether aqueous solution produced dispersions that gelled near body temperature and had a high yield value, preventing leakage of the formulation from the vaginal cavity. Intravaginal administration in rabbits showed that the glycyl-lysine-substituted gemini surfactant led to a higher gene expression compared with the parent unsubstituted gemini surfactant. This provides a proof-of-concept that amino acid substituted gemini surfactants can be used as noninvasive mucosal (vaginal) gene delivery systems to treat diseases associated with mucosal epithelia.
NASA Astrophysics Data System (ADS)
Wiktorowicz, Sloane J.; Millar-Blanchaer, Max; Perrin, Marshall D.; Graham, James R.; Fitzgerald, Michael P.; Maire, Jérôme; Ingraham, Patrick; Savransky, Dmitry; Macintosh, Bruce A.; Thomas, Sandrine J.; Chilcote, Jeffrey K.; Draper, Zachary H.; Song, Inseok; Cardwell, Andrew; Goodsell, Stephen J.; Hartung, Markus; Hibon, Pascale; Rantakyrö, Fredrik; Sadakuni, Naru
2014-07-01
We present on-sky polarimetric observations with the Gemini Planet Imager (GPI) obtained at straight Cassegrain focus on the Gemini South 8-m telescope. Observations of polarimetric calibrator stars, ranging from nearly un- polarized to strongly polarized, enable determination of the combined telescope and instrumental polarization. We find the conversion of Stokes I to linear and circular instrumental polarization in the instrument frame to be I --> (QIP, UIP, PIP, VIP) = (-0.037 +/- 0.010%, +0.4338 +/- 0.0075%, 0.4354 +/- 0.0075%, -6.64 +/- 0.56%). Such precise measurement of instrumental polarization enables ~0.1% absolute accuracy in measurements of linear polarization, which together with GPI's high contrast will allow GPI to explore scattered light from circumstellar disk in unprecedented detail, conduct observations of a range of other astronomical bodies, and potentially even study polarized thermal emission from young exoplanets. Observations of unpolarized standard stars also let us quantify how well GPI's differential polarimetry mode can suppress the stellar PSF halo. We show that GPI polarimetry achieves cancellation of unpolarized starlight by factors of 100-200, reaching the photon noise limit for sensitivity to circumstellar scattered light for all but the smallest separations at which the calibration for instrumental polarization currently sets the limit.
Garcia, M Teresa; Kaczerewska, Olga; Ribosa, Isabel; Brycki, Bogumił; Materna, Paulina; Drgas, Małgorzata
2016-07-01
Aerobic biodegradability and aquatic toxicity of five types of quaternary ammonium-based gemini surfactants have been examined. The effect of the spacer structure and the head group polarity on the ecological properties of a series of dimeric dodecyl ammonium surfactants has been investigated. Standard tests for ready biodegradability assessment (OECD 310) were conducted for C12 alkyl chain gemini surfactants containing oxygen, nitrogen or a benzene ring in the spacer linkage and/or a hydroxyethyl group attached to the nitrogen atom of the head groups. According to the results obtained, the gemini surfactants examined cannot be considered as readily biodegradable compounds. The negligible biotransformation of the gemini surfactants under the standard biodegradation test conditions was found to be due to their toxic effects on the microbial population responsible for aerobic biodegradation. Aquatic toxicity of gemini surfactants was evaluated against Daphnia magna. The acute toxicity values to Daphnia magna, IC50 at 48 h exposure, ranged from 0.6 to 1 mg/L. On the basis of these values, the gemini surfactants tested should be classified as toxic or very toxic to the aquatic environment. However, the dimeric quaternary ammonium-based surfactants examined result to be less toxic than their corresponding monomeric analogs. Nevertheless the aquatic toxicity of these gemini surfactants can be reduced by increasing the molecule hydrophilicity by adding a heteroatom to the spacer or a hydroxyethyl group to the polar head groups. Copyright © 2016 Elsevier Ltd. All rights reserved.
Detection Of DLA Candidate Galaxies Towards PKS 1756+237 And Q 0551-366 At z=1.67,1.96
NASA Astrophysics Data System (ADS)
Wong, Andre; Roth, K.
2007-12-01
We present the results of an adaptive optics imaging search for damped Lyman-α galaxies near the vicinity of quasars PKS 1756+237 and Q 0551-366. Prior spectral studies have detected damped Lyman-α or strong metal line absorption in the spectra of the two quasars corresponding to redshifts of z=1.67 and z=1.96, respectively. Both these systems are distinctive due to the confirmed detections of C I absorption, with molecular H also present in the spectra of the DLA towards Q 0551-366. Data was obtained in October 2001 and April 2002 using the University of Hawaii (IfA) Hokupa'a/QUIRC 36-element curvature AO system at Gemini North Observatory. The Hokupa'a AO system allowed users to guide on faint guide stars ( 17.5 mag), with a resulting resolution of 0.26” in the imaging data presented here. We have identified candidate DLA galaxies toward each of the quasars. The candidate for PKS 1756+237 is well separated from the quasar, while the Q 0551-366 candidate is only apparent after PSF subtraction. The Gemini Observatory is operated by the AURA, Inc. , under a cooperative agreement with the NSF on behalf of the Gemini partnership.
1966-02-08
S66-23592 (8 Feb. 1966) --- Astronaut Thomas P. Stafford, command pilot of the Gemini-9 prime crew, undergoes familiarization training with the Gemini-9 spacecraft at the McDonnell plant in St. Louis. Photo credit: NASA
1965-07-16
S65-28459 (16 July 1965) --- Astronaut Neil A. Armstrong, command pilot for the Gemini-5 backup crew, inside the Gemini Static Article 5 spacecraft prior to water egress training in the Gulf of Mexico. The training is part of the prelaunch schedule for prime and backup crew on the Gemini-5 mission.
Liftoff of Gemini-Titan 3 mission
1965-03-23
S65-14150 (23 March 1965) --- Launch view of the Gemini-Titan 3 mission. The GT-3 liftoff was at 9:24 a.m. (EST) on March 23, 1965. The Gemini-3 spacecraft "Molly Brown" carried astronauts Virgil I. Grissom, command pilot, and John W. Young, pilot, on three orbits of Earth.
Gemini surfactants from natural amino acids.
Pérez, Lourdes; Pinazo, Aurora; Pons, Ramon; Infante, Mrosa
2014-03-01
In this review, we report the most important contributions in the structure, synthesis, physicochemical (surface adsorption, aggregation and phase behaviour) and biological properties (toxicity, antimicrobial activity and biodegradation) of Gemini natural amino acid-based surfactants, and some potential applications, with an emphasis on the use of these surfactants as non-viral delivery system agents. Gemini surfactants derived from basic (Arg, Lys), neutral (Ser, Ala, Sar), acid (Asp) and sulphur containing amino acids (Cys) as polar head groups, and Geminis with amino acids/peptides in the spacer chain are reviewed. © 2013.
The Black Hole in the Most Massive Ultracompact Dwarf Galaxy M59-UCD3
NASA Astrophysics Data System (ADS)
Ahn, Christopher P.; Seth, Anil C.; Cappellari, Michele; Krajnović, Davor; Strader, Jay; Voggel, Karina T.; Walsh, Jonelle L.; Bahramian, Arash; Baumgardt, Holger; Brodie, Jean; Chilingarian, Igor; Chomiuk, Laura; den Brok, Mark; Frank, Matthias; Hilker, Michael; McDermid, Richard M.; Mieske, Steffen; Neumayer, Nadine; Nguyen, Dieu D.; Pechetti, Renuka; Romanowsky, Aaron J.; Spitler, Lee
2018-05-01
We examine the internal properties of the most massive ultracompact dwarf galaxy (UCD), M59-UCD3, by combining adaptive-optics-assisted near-IR integral field spectroscopy from Gemini/NIFS and Hubble Space Telescope (HST) imaging. We use the multiband HST imaging to create a mass model that suggests and accounts for the presence of multiple stellar populations and structural components. We combine these mass models with kinematics measurements from Gemini/NIFS to find a best-fit stellar mass-to-light ratio (M/L) and black hole (BH) mass using Jeans anisotropic models (JAMs), axisymmetric Schwarzschild models, and triaxial Schwarzschild models. The best-fit parameters in the JAM and axisymmetric Schwarzschild models have BHs between 2.5 and 5.9 million solar masses. The triaxial Schwarzschild models point toward a similar BH mass but show a minimum χ 2 at a BH mass of ∼0. Models with a BH in all three techniques provide better fits to the central V rms profiles, and thus we estimate the BH mass to be {4.2}-1.7+2.1× {10}6 M ⊙ (estimated 1σ uncertainties). We also present deep radio imaging of M59-UCD3 and two other UCDs in Virgo with dynamical BH mass measurements, and we compare these to X-ray measurements to check for consistency with the fundamental plane of BH accretion. We detect faint radio emission in M59cO but find only upper limits for M60-UCD1 and M59-UCD3 despite X-ray detections in both these sources. The BH mass and nuclear light profile of M59-UCD3 suggest that it is the tidally stripped remnant of a ∼109–1010 M ⊙ galaxy.
No evidence for Lyman α emission in spectroscopy of z > 7 candidate galaxies
NASA Astrophysics Data System (ADS)
Caruana, Joseph; Bunker, Andrew J.; Wilkins, Stephen M.; Stanway, Elizabeth R.; Lacy, Mark; Jarvis, Matt J.; Lorenzoni, Silvio; Hickey, Samantha
2012-12-01
We present Gemini/Gemini Near Infrared Spectrograph (GNIRS) spectroscopic observations of four z-band (z ≈ 7) dropout galaxies and Very Large Telescope (VLT)/XSHOOTER observations of one z-band dropout and three Y-band (z ≈ 8-9) dropout galaxies in the Hubble Ultra Deep Field, which were selected with Wide Field Camera 3 imaging on the Hubble Space Telescope. We find no evidence of Lyman α emission with a typical 5σ sensitivity of 5 × 10-18 erg cm-2 s-1, and use the upper limits on Lyman α flux and the broad-band magnitudes to constrain the rest-frame equivalent widths for this line emission. Accounting for incomplete spectral coverage, we survey 3.0 z-band dropouts and 2.9 Y-band dropouts to a Lyman α rest-frame equivalent width limit >120 Å (for an unresolved emission line); for an equivalent width limit of 50 Å the effective numbers of drop-outs surveyed fall to 1.2 z-band drop-outs and 1.5 Y-band drop-outs. A simple model where the fraction of high rest-frame equivalent width emitters follows the trend seen at z = 3-6.5 is inconsistent with our non-detections at z = 7-9 at the ≈1σ level for spectrally unresolved lines, which may indicate that a significant neutral H I fraction in the intergalactic medium suppresses the Lyman α line in z-drop and Y-drop galaxies at z > 7. Based on observations collected at the European Organization for Astronomical Research in the Southern Hemisphere, Chile, as part of programme 086.A-0968(B).
THE MULTIPHASE STRUCTURE AND POWER SOURCES OF GALACTIC WINDS IN MAJOR MERGERS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rupke, David S. N.; Veilleux, Sylvain, E-mail: drupke@gmail.com
2013-05-01
Massive, galaxy-scale outflows are known to be ubiquitous in major mergers of disk galaxies in the local universe. In this paper, we explore the multiphase structure and power sources of galactic winds in six ultraluminous infrared galaxies (ULIRGs) at z < 0.06 using deep integral field spectroscopy with the Gemini Multi-Object Spectrograph (GMOS) on Gemini North. We probe the neutral, ionized, and dusty gas phases using Na I D, strong emission lines ([O I], H{alpha}, and [N II]), and continuum colors, respectively. We separate outflow motions from those due to rotation and tidal perturbations, and find that all of themore » galaxies in our sample host high-velocity flows on kiloparsec scales. The properties of these outflows are consistent with multiphase (ionized, neutral, and dusty) collimated bipolar winds emerging along the minor axis of the nuclear disk to scales of 1-2 kpc. In two cases, these collimated winds take the form of bipolar superbubbles, identified by clear kinematic signatures. Less collimated (but still high-velocity) flows are also present on scales up to 5 kpc in most systems. The three galaxies in our sample with obscured QSOs host higher velocity outflows than those in the three galaxies with no evidence for an active galactic nucleus. The peak outflow velocity in each of the QSOs is in the range 1450-3350 km s{sup -1}, and the highest velocities (2000-3000 km s{sup -1}) are seen only in ionized gas. The outflow energy and momentum in the QSOs are difficult to produce from a starburst alone, but are consistent with the QSO contributing significantly to the driving of the flow. Finally, when all gas phases are accounted for, the outflows are massive enough to provide negative feedback to star formation.« less
StarNet: An application of deep learning in the analysis of stellar spectra
NASA Astrophysics Data System (ADS)
Kielty, Collin; Bialek, Spencer; Fabbro, Sebastien; Venn, Kim; O'Briain, Teaghan; Jahandar, Farbod; Monty, Stephanie
2018-06-01
In an era when spectroscopic surveys are capable of collecting spectra for hundreds of thousands of stars, fast and efficient analysis methods are required to maximize scientific impact. These surveys provide a homogeneous database of stellar spectra that are ideal for machine learning applications. In this poster, we present StarNet: a convolutional neural network model applied to the analysis of both SDSS-III APOGEE DR13 and synthetic stellar spectra. When trained on synthetic spectra alone, the calculated stellar parameters (temperature, surface gravity, and metallicity) are of excellent precision and accuracy for both APOGEE data and synthetic data, over a wide range of signal-to-noise ratios. While StarNet was developed using the APOGEE observed spectra and corresponding ASSeT synthetic grid, we suggest that this technique is applicable to other spectral resolutions, spectral surveys, and wavelength regimes. As a demonstration of this, we present a StarNet model trained on lower resolution, R=6000, IR synthetic spectra, describing the spectra delivered by Gemini/NIFS and the forthcoming Gemini/GIRMOS instrument (PI Sivanandam, UToronto). Preliminary results suggest that the stellar parameters determined from this low resolution StarNet model are comparable in precision to the high-resolution APOGEE results. The success of StarNet at lower resolution can be attributed to (1) a large training set of synthetic spectra (N ~200,000) with a priori stellar labels, and (2) the use of the entire spectrum in the solution rather than a few weighted windows, which are common methods in other spectral analysis tools (e.g. FERRE or The Cannon). Remaining challenges in our StarNet applications include rectification, continuum normalization, and wavelength coverage. Solutions to these problems could be used to guide decisions made in the development of future spectrographs, spectroscopic surveys, and data reduction pipelines, such as for the future MSE.
The T dwarf population in the UKIDSS LAS .
NASA Astrophysics Data System (ADS)
Cardoso, C. V.; Burningham, B.; Smith, L.; Smart, R.; Pinfield, D.; Magazzù, A.; Ghinassi, F.; Lattanzi, M.
We present the most recent results from the UKIDSS Large Area Survey (LAS) census and follow up of new T brown dwarfs in the local field. The new brown dwarf candidates are identified using optical and infrared survey photometry (UKIDSS and SDSS) and followed up with narrow band methane photometry (TNG) and spectroscopy (Gemini and Subaru) to confirm their brown dwarf nature. Employing this procedure we have discovered several dozens of new T brown dwarfs in the field. Using methane differential photometry as a proxy for spectral type for T brown dwarfs has proved to be a very efficient technique. This method can be useful in the future to reliably identify brown dwarfs in deep surveys that produce large samples of faint targets where spectroscopy is not feasible for all candidates. With this statistical robust sample of the mid and late T brown dwarf field population we were also able to address the discrepancies between the observed field space density and the expected values given the most accepted forms of the IMF of young clusters.
The Swift GRB Host Galaxy Legacy Survey
NASA Astrophysics Data System (ADS)
Perley, Daniel
2015-08-01
I will describe the Swift Host Galaxy Legacy Survey (SHOALS), a comprehensive multiwavelength program to characterize the demographics of the GRB host population and its redshift evolution from z=0 to z=7. Using unbiased selection criteria we have designated a subset of 119 Swift gamma-ray bursts which are now being targeted with intensive observational follow-up. Deep Spitzer imaging of every field has already been obtained and analyzed, with major programs ongoing at Keck, GTC, Gemini, VLT, and Magellan to obtain complementary optical/NIR photometry and spectroscopy to enable full SED modeling and derivation of fundamental physical parameters such as mass, extinction, and star-formation rate. Using these data I will present an unbiased measurement of the GRB host-galaxy luminosity and mass distributions and their evolution with redshift, compare GRB hosts to other star-forming galaxy populations, and discuss implications for the nature of the GRB progenitor and the ability of GRBs to serve as tools for measuring and studying cosmic star-formation in the distant universe.
GEMINI-8 - TRAINING - WATER EGRESS TRAINING - GULF
1966-01-15
S66-17288 (15 Jan. 1966) --- Astronauts Neil A. Armstrong (on left), command pilot, and David R. Scott, pilot of the Gemini-8 prime crew, use a boilerplate model of a Gemini spacecraft during water egress training in the Gulf of Mexico. Three Manned Spacecraft Center swimmers assist in the training exercise. Photo credit: NASA
Kumar, Vikash; Chatterjee, Amrita; Kumar, Nupur; Ganguly, Anasuya; Chakraborty, Indranil; Banerjee, Mainak
2014-10-09
Four new D-glucose derived m-s-m type gemini surfactants with variable spacer and tail length have been synthesized by a simple and efficient synthetic methodology utilizing the free C-3 hydroxy group of diisopropylidene glucose. The synthetic route to these gemini surfactants with a quaternary ammonium group as polar head group involves a sequence of simple reactions including alkylation, imine formation, quaternization of amine etc. The surface properties of the new geminis were evaluated by surface tension and conductivity measurements. These gemini surfactants showed low cytotoxicity by MTT assay on HeLa cell line. The DNA binding capabilities of these surfactants were determined by agarose gel electrophoresis, fluorescence titration, and DLS experiments. The preliminary studies by agarose gel electrophoresis indicated chain length dependent DNA binding abilities, further supported by ethidium bromide exclusion experiments. Two of the D-glucose derived gemini surfactants showed effective binding with pET-28a plasmid DNA (pDNA) at relatively low N/P ratio (i.e., cationic nitrogen/DNA phosphate molar ratio). Copyright © 2014 Elsevier Ltd. All rights reserved.
Food packages for Space Shuttle
NASA Technical Reports Server (NTRS)
Fohey, M. F.; Sauer, R. L.; Westover, J. B.; Rockafeller, E. F.
1978-01-01
The paper reviews food packaging techniques used in space flight missions and describes the system developed for the Space Shuttle. Attention is directed to bite-size food cubes used in Gemini, Gemini rehydratable food packages, Apollo spoon-bowl rehydratable packages, thermostabilized flex pouch for Apollo, tear-top commercial food cans used in Skylab, polyethylene beverage containers, Skylab rehydratable food package, Space Shuttle food package configuration, duck-bill septum rehydration device, and a drinking/dispensing nozzle for Space Shuttle liquids. Constraints and testing of packaging is considered, a comparison of food package materials is presented, and typical Shuttle foods and beverages are listed.
NASA Technical Reports Server (NTRS)
Llewellyn, J. A.
1967-01-01
The Launch Complex 37 lightning strike of July 27, 1967, was reviewed and compared to a similar incident on the Gemini Program. Available data indicate little likelihood of damaging currents having been present in SA-204 Launch Vehicle or the ground equipment during the July 27th incident. Based on the results of subsystem and system testing after the strike, anticipated results of future testing, the six months elapsed time between the strike-and launch, and the fact that much of the critical airborne electrical/electronic equipment has been removed since the strike for other reasons, no new actions are considered necessary at this time in the Gemini case, significant failures occurred in both airborne and ground circuits. Due to the resultant semi, condlictor uncertainty, and the relatively' short time prior to planned launch, all critical airborne components containing semiconduetors were replaced, and a sophisticated data comparison task was implemented.
NASA Technical Reports Server (NTRS)
Medved, D. B.
1971-01-01
The results of the reduction and analysis of data obtained from the S026 experiment from Gemini 10 and 11 flights are presented. The electron and ion sensors were continuously operative throughout both missions from shroud removal (about 6 minutes after Agena liftoff to power-down conditions one week later). Data on ion and electron currents, electron temperature, and vehicle potential were obtained at a sample rate of 32 times per second on positive ions for each of two ion sensors and once every 1.067 seconds for the electron sensor. Only the data reduction of the Gemini plasma wake measurements comprising roughly twenty minutes of data for six maneuvers programed for wake measurements are considered. The intermediate depletion zone, between 1 and 10 vehicle radii downstream from the object, is emphasized. The smallest characteristic radius of interest is 1.34 feet and the largest is 5 feet. This implies a separation span extending from approximately 1.5 feet at the closest approach to at least 50 feet into the far field.
Use of XML and Java for collaborative petroleum reservoir modeling on the Internet
NASA Astrophysics Data System (ADS)
Victorine, John; Watney, W. Lynn; Bhattacharya, Saibal
2005-11-01
The GEMINI (Geo-Engineering Modeling through INternet Informatics) is a public-domain, web-based freeware that is made up of an integrated suite of 14 Java-based software tools to accomplish on-line, real-time geologic and engineering reservoir modeling. GEMINI facilitates distant collaborations for small company and academic clients, negotiating analyses of both single and multiple wells. The system operates on a single server and an enterprise database. External data sets must be uploaded into this database. Feedback from GEMINI users provided the impetus to develop Stand Alone Web Start Applications of GEMINI modules that reside in and operate from the user's PC. In this version, the GEMINI modules run as applets, which may reside in local user PCs, on the server, or Java Web Start. In this enhanced version, XML-based data handling procedures are used to access data from remote and local databases and save results for later access and analyses. The XML data handling process also integrates different stand-alone GEMINI modules enabling the user(s) to access multiple databases. It provides flexibility to the user to customize analytical approach, database location, and level of collaboration. An example integrated field-study using GEMINI modules and Stand Alone Web Start Applications is provided to demonstrate the versatile applicability of this freeware for cost-effective reservoir modeling.
Use of XML and Java for collaborative petroleum reservoir modeling on the Internet
Victorine, J.; Watney, W.L.; Bhattacharya, S.
2005-01-01
The GEMINI (Geo-Engineering Modeling through INternet Informatics) is a public-domain, web-based freeware that is made up of an integrated suite of 14 Java-based software tools to accomplish on-line, real-time geologic and engineering reservoir modeling. GEMINI facilitates distant collaborations for small company and academic clients, negotiating analyses of both single and multiple wells. The system operates on a single server and an enterprise database. External data sets must be uploaded into this database. Feedback from GEMINI users provided the impetus to develop Stand Alone Web Start Applications of GEMINI modules that reside in and operate from the user's PC. In this version, the GEMINI modules run as applets, which may reside in local user PCs, on the server, or Java Web Start. In this enhanced version, XML-based data handling procedures are used to access data from remote and local databases and save results for later access and analyses. The XML data handling process also integrates different stand-alone GEMINI modules enabling the user(s) to access multiple databases. It provides flexibility to the user to customize analytical approach, database location, and level of collaboration. An example integrated field-study using GEMINI modules and Stand Alone Web Start Applications is provided to demonstrate the versatile applicability of this freeware for cost-effective reservoir modeling. ?? 2005 Elsevier Ltd. All rights reserved.
Fostering Student Awareness in Observatory STEM Careers
NASA Astrophysics Data System (ADS)
Keonaonaokalauae Acohido, Alexis Ann; Michaud, Peter D.; Gemini Public Information and Outreach Staff
2016-01-01
It takes more than scientists to run an observatory. Like most observatories, only about 20% of Gemini Observatory's staff is PhD. Scientists, but 100% of those scientists would not be able to do their jobs without the help of engineers, administrators, and other support staff that make things run smoothly. Gemini's Career Brochure was first published in 2014 to show that there are many different career paths available (especially in local host communities) at an astronomical observatory. Along with the printed career brochure, there are supplementary videos available on Gemini's website and Youtube pages that provide a more detailed and personal glimpse into the day-in-the-life of a wide assortment of Gemini employees. A weakness in most observatory's outreach programming point to the notion that students (and teachers) feel there is a disconnect between academics and where students would like to end up in their career future. This project is one of the ways Gemini addresses these concerns. During my 6-month internship at Gemini, I have updated the Career Brochure website conducted more in-depth interviews with Gemini staff to include as inserts with the brochure, and expanded the array of featured careers. The goal of my work is to provide readers with detailed and individualized employee career paths to show; 1) that there are many ways to establish a career in the STEM fields, and 2), that the STEM fields are vastly diverse.
Gemini 3 prime crew egress throught command pilot's hatch during training
NASA Technical Reports Server (NTRS)
1965-01-01
Both members of the Gemini-Titan 3 prime crew egress through the left, or command pilot's hatch, into the Gulf of Mexico during specialized training in egress from the Gemini spacecraft. Astronaut Virgil I. Grissom, the command pilot, has already climbed into a raft, as Astronaut John W. Young, the pilot, egresses from the spacecraft.
Personnel - Gemini-Titan (GT)-10 - Mission Control Center (MCC) - MSC
1966-07-18
S66-43377 (18 July 1966) --- Standing at the flight director's console, viewing the Gemini-10 flight display in the Mission Control Center, are (left to right) William C. Schneider, Mission Director; Glynn Lunney, Prime Flight Director; Christopher C. Kraft Jr., MSC Director of Flight Operations; and Charles W. Mathews, Manager, Gemini Program Office. Photo credit: NASA
Mexico, Arizona and New Mexico as seen from the Gemini 12 spacecraft
NASA Technical Reports Server (NTRS)
1966-01-01
Northern portion of Sonora, Mexico; southeastern Arizona and southwestern New Mexico, as seen from the Gemini 12 spacecraft during its 30th revolution of the earth. Includes the Tucson, Phoenix, Mogollon Rim, and Painted Desert areas. A 100 ft. tether line connects the Agena Target Docking Vehicle with the Gemini 12 spacecraft.
GEMINI-TITAN (GT)-9A (SUITING-UP) - ASTRONAUT THOMAS P. STAFFORD - MISC. - CAPE
1966-06-03
S66-34060 (3 June 1966) --- Astronaut Thomas P. Stafford, Gemini-9A prime crew command pilot, adjusts a sleeve of his spacesuit during suiting up procedures at Launch Complex 16, Kennedy Space Center. The Gemini-9A liftoff was at 8:39 a.m. (EST), June 3, 1966. Photo credit: NASA
Nguyen, Nghi C; Vercher-Conejero, Jose L; Sattar, Abdus; Miller, Michael A; Maniawski, Piotr J; Jordan, David W; Muzic, Raymond F; Su, Kuan-Hao; O'Donnell, James K; Faulhaber, Peter F
2015-09-01
We report our initial clinical experience for image quality and diagnostic performance of a digital PET prototype scanner with time-of-flight (DigitalTF), compared with an analog PET scanner with time-of-flight (GeminiTF PET/CT). Twenty-one oncologic patients, mean age 58 y, first underwent clinical (18)F-FDG PET/CT on the GeminiTF. The scanner table was then withdrawn while the patient remained on the table, and the DigitalTF was inserted between the GeminiTF PET and CT scanner. The patients were scanned for a second time using the same PET field of view with CT from the GeminiTF for attenuation correction. Two interpreters reviewed the 2 sets of PET/CT images for overall image quality, lesion conspicuity, and sharpness. They counted the number of suggestive (18)F-FDG-avid lesions and provided the TNM staging for the 5 patients referred for initial staging. Standardized uptake values (SUVs) and SUV gradients as a measure of lesion sharpness were obtained. The DigitalTF showed better image quality than the GeminiTF. In a side-by-side comparison using a 5-point scale, lesion conspicuity (4.3 ± 0.6), lesion sharpness (4.3 ± 0.6), and diagnostic confidence (3.4 ± 0.7) were better with DigitalTF than with GeminiTF (P < 0.01). In 52 representative lesions, the lesion maximum SUV was 36% higher with DigitalTF than with GeminiTF, lesion-to-blood-pool SUV ratio was 59% higher, and SUV gradient was 51% higher, with good correlation between the 2 scanners. Lesions less than 1.5 cm showed a greater increase in SUV from GeminiTF to DigitalTF than those lesions 1.5 cm or greater. In 5 of 21 patients, DigitalTF showed an additional 8 suggestive lesions that were not seen using GeminiTF. In the 15 restaging patients, the true-negative rate was 100% and true-positive rate was 78% for both scanners. In the 5 patients for initial staging, DigitalTF led to upstaging in 2 patients and showed the same staging in the other 3 patients, compared with GeminiTF. DigitalTF provides better image quality, diagnostic confidence, and accuracy than GeminiTF. DigitalTF may be the most beneficial in detecting small tumor lesions and disease staging. © 2015 by the Society of Nuclear Medicine and Molecular Imaging, Inc.
Suzaku Observations of the Monogem Ring and the Origin of the Gemini Hα Ring
NASA Astrophysics Data System (ADS)
Knies, Jonathan R.; Sasaki, Manami; Plucinsky, Paul P.
2018-04-01
We present the analysis of Suzaku X-ray observations of the Galactic supernova remnant (SNR) 'Monogem Ring', a large structure observed in X-rays with an extent of ≈ 25°, located at an anti-centre position. One observation close to the shock also coincides with a large ring-like structure observed in Hα, which is called the 'Gemini Hα ring'. We investigate the origin of the ring-like structure and also possible interactions with the SNR. We show that the SNR is expanding in a region with a density gradient, which has an effect on the morphology of the SNR and the properties of the plasma. The X-ray spectra are fit well with a collisional ionisation equilibrium (CIE) model with a temperature of kT ≈ 0.3 keV. The spectra obtained at a position where the SNR coincides with the Gemini Hα ring are better described with non-equilibrium ionisation (NEI) with a temperature of kT ≈ 1.0 keV. Based on the spectral analysis results, we estimate an age of t ≈ 6.8 × 104 yr for a distance of ≈300 pc, using the Sedov-Taylor solution. We have identified several early-type stars in the Hipparcos catalogue at a distance of 200- 300pc, which have most likely formed the 'Gemini Hα ring' by their powerful stellar winds.
Cardoso, Ana M; Morais, Catarina M; Silva, Sandra G; Marques, Eduardo F; de Lima, Maria C Pedroso; Jurado, Maria Amália S
2014-10-20
Gemini surfactants have been successfully used as components of gene delivery systems. In the present work, a family of gemini surfactants, represented by the general structure [CmH2m+1(CH3)2N(+)(CH2)sN(+)(CH3)2CmH2m+1]2Br(-), or simply m-s-m, was used to prepare cationic gene carriers, aiming at their application in transfection studies. An extensive characterization of the gemini surfactant-based complexes, produced with and without the helper lipids cholesterol and DOPE, was carried out in order to correlate their physico-chemical properties with transfection efficiency. The most efficient complexes were those containing helper lipids, which, combining amphiphiles with propensity to form structures with different intrinsic curvatures, displayed a morphologically labile architecture, putatively implicated in the efficient DNA release upon complex interaction with membranes. While complexes lacking helper lipids were translocated directly across the lipid bilayer, complexes containing helper lipids were taken up by cells also by macropinocytosis. This study contributes to shed light on the relationship between important physico-chemical properties of surfactant-based DNA vectors and their efficiency to promote gene transfer, which may represent a step forward to the rational design of gene delivery systems. Copyright © 2014 Elsevier B.V. All rights reserved.
Sum, Chi Hong; Nafissi, Nafiseh; Slavcev, Roderick A.; Wettig, Shawn
2015-01-01
In combination with novel linear covalently closed (LCC) DNA minivectors, referred to as DNA ministrings, a gemini surfactant-based synthetic vector for gene delivery has been shown to exhibit enhanced delivery and bioavailability while offering a heightened safety profile. Due to topological differences from conventional circular covalently closed (CCC) plasmid DNA vectors, the linear topology of LCC DNA ministrings may present differences with regards to DNA interaction and the physicochemical properties influencing DNA-surfactant interactions in the formulation of lipoplexed particles. In this study, N,N-bis(dimethylhexadecyl)-α,ω-propanediammonium(16-3-16)gemini-based synthetic vectors, incorporating either CCC plasmid or LCC DNA ministrings, were characterized and compared with respect to particle size, zeta potential, DNA encapsulation, DNase sensitivity, and in vitro transgene delivery efficacy. Through comparative analysis, differences between CCC plasmid DNA and LCC DNA ministrings led to variations in the physical properties of the resulting lipoplexes after complexation with 16-3-16 gemini surfactants. Despite the size disparities between the plasmid DNA vectors (CCC) and DNA ministrings (LCC), differences in DNA topology resulted in the generation of lipoplexes of comparable particle sizes. The capacity for ministring (LCC) derived lipoplexes to undergo complete counterion release during lipoplex formation contributed to improved DNA encapsulation, protection from DNase degradation, and in vitro transgene delivery. PMID:26561857
Donkuru, McDonald; Michel, Deborah; Awad, Hanan; Katselis, George; El-Aneed, Anas
2016-05-13
Diquaternary gemini surfactants have successfully been used to form lipid-based nanoparticles that are able to compact, protect, and deliver genetic materials into cells. However, what happens to the gemini surfactants after they have released their therapeutic cargo is unknown. Such knowledge is critical to assess the quality, safety, and efficacy of gemini surfactant nanoparticles. We have developed a simple and rapid liquid chromatography electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) method for the quantitative determination of various structures of gemini surfactants in cells. Hydrophilic interaction liquid chromatography (HILIC) was employed allowing for a short simple isocratic run of only 4min. The lower limit of detection (LLOD) was 3ng/mL. The method was valid to 18 structures of gemini surfactants belonging to two different structural families. A full method validation was performed for two lead compounds according to USFDA guidelines. The HILIC-MS/MS method was compatible with the physicochemical properties of gemini surfactants that bear a permanent positive charge with both hydrophilic and hydrophobic elements within their molecular structure. In addition, an effective liquid-liquid extraction method (98% recovery) was employed surpassing previously used extraction methods. The analysis of nanoparticle-treated cells showed an initial rise in the analyte intracellular concentration followed by a maximum and a somewhat more gradual decrease of the intracellular concentration. The observed intracellular depletion of the gemini surfactants may be attributable to their bio-transformation into metabolites and exocytosis from the host cells. Obtained cellular data showed a pattern that grants additional investigations, evaluating metabolite formation and assessing the subcellular distribution of tested compounds. Copyright © 2016 Elsevier B.V. All rights reserved.
Gemini Program Mission Report: Gemini IV
NASA Technical Reports Server (NTRS)
1965-01-01
The second manned mission of the Gemini Program, Gemini IV, was launched from Complex 19 at Cape Kennedy, Florida, at 10:16 a.m. e.s.t. on June 3, 1965. The mission was successfully concluded on June 7, 1965, with the recovery of the spacecraft by the prime recovery ship, the aircraft carrier U.S.S. Wasp, at 27 deg 44' N. latitude, 74 deg 11' W. longitude at 2:28 p.m. e.s.t. This manned long-duration flight was accomplished 10 weeks after the three-orbit manned flight which qualified the Gemini spacecraft and systems for orbital flight. The spacecraft was manned by Astronaut James A. McDivitt, command pilot, and Astronaut Edward H. White II, pilot. The flight crew completed the 4-day mission in excellent physical condition, and demonstrated full control of the spacecraft and competent management of all aspects of the mission.
Direct Evidence for an Enhancement of Helium in Giant Stars in Omega Centauri
NASA Astrophysics Data System (ADS)
Dupree, A. K.; Strader, Jay; Smith, Graeme H.
2011-02-01
The double main sequence identified in the globular cluster Omega Centauri has been interpreted using isochrones to indicate a large variation in the abundance of helium. If true, a helium enhancement carries strong implications for the chemical and stellar evolutionary history of this cluster. However, only indirect measures currently support this conjecture. We report the discovery of a variation in the line strength of the near-infrared He I 10830 Å transition in 12 similar red giants in Omega Centauri observed with PHOENIX on Gemini-S. Abundances of these stars derived from Magellan/MIKE spectra taken at the Las Campanas Observatory show that the helium transition is not detected in the most metal-poor population ([Fe/H] < -1.8), yet is present in the majority of stars with [Fe/H] >= -1.8. These observations give the first direct evidence for an enhancement of helium in Omega Centauri. The appearance of helium appears better correlated with increased [Al/Fe] and [Na/Fe] abundances than as a function of [Fe/H], giving observational support to the presence of high-temperature H burning in a prior generation of stars. Data presented herein were obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the Science and Technology Facilities Council (United Kingdom), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), Ministério da Ciência e Tecnologia (Brazil), and Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina). This paper also includes spectra gathered with the 6.5 m Magellan Telescope/CLAY located at Las Campanas Observatory, Chile.
Stellar Variability at the Main-sequence Turnoff of the Intermediate-age LMC Cluster NGC 1846
NASA Astrophysics Data System (ADS)
Salinas, R.; Pajkos, M. A.; Vivas, A. K.; Strader, J.; Contreras Ramos, R.
2018-04-01
Intermediate-age (IA) star clusters in the Large Magellanic Cloud (LMC) present extended main-sequence turn-offs (MSTO) that have been attributed to either multiple stellar populations or an effect of stellar rotation. Recently it has been proposed that these extended main sequences can also be produced by ill-characterized stellar variability. Here we present Gemini-S/Gemini Multi-Object Spectrometer (GMOS) time series observations of the IA cluster NGC 1846. Using differential image analysis, we identified 73 new variable stars, with 55 of those being of the Delta Scuti type, that is, pulsating variables close the MSTO for the cluster age. Considering completeness and background contamination effects, we estimate the number of δ Sct belonging to the cluster between 40 and 60 members, although this number is based on the detection of a single δ Sct within the cluster half-light radius. This amount of variable stars at the MSTO level will not produce significant broadening of the MSTO, albeit higher-resolution imaging will be needed to rule out variable stars as a major contributor to the extended MSTO phenomenon. Though modest, this amount of δ Sct makes NGC 1846 the star cluster with the highest number of these variables ever discovered. Lastly, our results present a cautionary tale about the adequacy of shallow variability surveys in the LMC (like OGLE) to derive properties of its δ Sct population. Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the National Research Council (Canada), CONICYT (Chile), Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina), and Ministério da Ciência, Tecnologia e Inovação (Brazil).
GEMINI-TITAN (GT)-12 - EARTH SKY - NORTHERN SONORA, MEXICO - OUTER SPACE
1966-11-13
S66-62794 (13 Nov. 1966) --- Northern portion of Sonora, Mexico; southeastern Arizona and southwestern New Mexico, as seen from the Gemini-12 spacecraft during its 30th revolution of Earth. Includes the Tucson, Phoenix, Mogollon Rim, and Painted Desert areas. A 100-foot tether line connects the Agena Target Docking Vehicle with the Gemini-12 spacecraft. Photo credit: NASA.
(GT-6 PRIME CREW((PREFLIGHT ACTIVITY) - ASTRONAUT THOMAS P. STAFFORD - MISC.
1965-12-12
S65-59977 (15 Dec. 1965) --- Astronauts Thomas P. Stafford (foreground), Gemini-6 prime crew pilot; and Alan B. Shepard Jr., chief, Astronaut Office, Manned Spacecraft Center, look over a Gemini mission chart in the suiting trailer at Launch Complex 16 during the Gemini-6 prelaunch countdown at Cape Kennedy, Florida. Photo credit: NASA or National Aeronautics and Space Administration
PRESS CONFERENCE - GEMINI-TITAN (GT)-10 - MSC
1966-08-01
S66-39897 (1 Aug. 1966) --- Astronaut John W. Young, Gemini-10 command pilot, uses a chalk drawing on a blackboard to illustrate how astronaut Michael Collins, Gemini-10 pilot, looked when he inspected the Agena Target Docking Vehicle during his extravehicular activity. Young was discussing the mission before a gathering of news media representatives in the Building 1 auditorium. Photo credit: NASA
GEMINI-TITAN (GT)-8 - INSIGNIA - COLOR DESIGN - MSC
1966-03-01
S66-23978 (March 1966) --- Color design for the emblem of the Gemini-8 spaceflight. Roman numeral indicates the eighth flight in the Gemini series. Prime crewmen for the mission are astronauts Neil A. Armstrong, command pilot; and David R. Scott, pilot. The NASA insignia design for Gemini flights is reserved for use by the astronauts and for other official use as the NASA Administrator may authorize. Public availability has been approved only in the form of illustrations by the various news media. When and if there is any change in this policy, which we do not anticipate, it will be publicly announced. Photo credit: NASA
DOE Office of Scientific and Technical Information (OSTI.GOV)
Parsons, S. G.; Marsh, T. R.; Gaensicke, B. T.
Using Liverpool Telescope+RISE photometry we identify the 2.78 hr period binary star CSS 41177 as a detached eclipsing double white dwarf binary with a 21,100 K primary star and a 10,500 K secondary star. This makes CSS 41177 only the second known eclipsing double white dwarf binary after NLTT 11748. The 2 minute long primary eclipse is 40% deep and the secondary eclipse 10% deep. From Gemini+GMOS spectroscopy, we measure the radial velocities of both components of the binary from the H{alpha} absorption line cores. These measurements, combined with the light curve information, yield white dwarf masses of M{sub 1}more » = 0.283 {+-} 0.064 M{sub sun} and M{sub 2} = 0.274 {+-} 0.034 M{sub sun}, making them both helium core white dwarfs. As an eclipsing, double-lined spectroscopic binary, CSS 41177 is ideally suited to measuring precise, model-independent masses and radii. The two white dwarfs will merge in roughly 1.1 Gyr to form a single sdB star.« less
Production mechanism of new neutron-rich heavy nuclei in the 136Xe +198Pt reaction
NASA Astrophysics Data System (ADS)
Li, Cheng; Wen, Peiwei; Li, Jingjing; Zhang, Gen; Li, Bing; Xu, Xinxin; Liu, Zhong; Zhu, Shaofei; Zhang, Feng-Shou
2018-01-01
The multinucleon transfer reaction of 136Xe +198Pt at Elab = 7.98 MeV/nucleon is investigated by using the improved quantum molecular dynamics model. The quasielastic, deep-inelastic, and quasifission collision mechanisms are studied via analyzing the angular distributions of fragments and the energy dissipation processes during the collisions. The measured isotope production cross sections of projectile-like fragments are reasonably well reproduced by the calculation of the ImQMD model together with the GEMINI code. The isotope production cross sections for the target-like fragments and double differential cross sections of 199Pt, 203Pt, and 208Pt are calculated. It is shown that about 50 new neutron-rich heavy nuclei can be produced via deep-inelastic collision mechanism, where the production cross sections are from 10-3 to 10-6 mb. The corresponding emission angle and the kinetic energy for these new neutron-rich nuclei locate at 40∘-60∘ and 100-200 MeV, respectively.
The Subaru/XMM-Newton Deep Survey (SXDS). V. Optically Faint Variable Object Survey
NASA Astrophysics Data System (ADS)
Morokuma, Tomoki; Doi, Mamoru; Yasuda, Naoki; Akiyama, Masayuki; Sekiguchi, Kazuhiro; Furusawa, Hisanori; Ueda, Yoshihiro; Totani, Tomonori; Oda, Takeshi; Nagao, Tohru; Kashikawa, Nobunari; Murayama, Takashi; Ouchi, Masami; Watson, Mike G.; Richmond, Michael W.; Lidman, Christopher; Perlmutter, Saul; Spadafora, Anthony L.; Aldering, Greg; Wang, Lifan; Hook, Isobel M.; Knop, Rob A.
2008-03-01
We present our survey for optically faint variable objects using multiepoch (8-10 epochs over 2-4 years) i'-band imaging data obtained with Subaru Suprime-Cam over 0.918 deg2 in the Subaru/XMM-Newton Deep Field (SXDF). We found 1040 optically variable objects by image subtraction for all the combinations of images at different epochs. This is the first statistical sample of variable objects at depths achieved with 8-10 m class telescopes or the Hubble Space Telescope. The detection limit for variable components is i'vari ~ 25.5 mag. These variable objects were classified into variable stars, supernovae (SNe), and active galactic nuclei (AGNs), based on the optical morphologies, magnitudes, colors, and optical-mid-infrared colors of the host objects, spatial offsets of variable components from the host objects, and light curves. Detection completeness was examined by simulating light curves for periodic and irregular variability. We detected optical variability for 36% +/- 2% (51% +/- 3% for a bright sample with i' < 24.4 mag) of X-ray sources in the field. Number densities of variable objects as functions of time intervals Δ t and variable component magnitudes i'vari are obtained. Number densities of variable stars, SNe, and AGNs are 120, 489, and 579 objects deg-2, respectively. Bimodal distributions of variable stars in the color-magnitude diagrams indicate that the variable star sample consists of bright (V ~ 22 mag) blue variable stars of the halo population and faint (V ~ 23.5 mag) red variable stars of the disk population. There are a few candidates of RR Lyrae providing a possible number density of ~10-2 kpc-3 at a distance of >150 kpc from the Galactic center. Based in part on data collected at Subaru Telescope, which is operated by the National Astronomical Observatory of Japan. Based on observations (program GN-2002B-Q-30) obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (US), the Particle Physics and Astronomy Research Council (UK), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), CNPq (Brazil), and CONICET (Argentina).
DOE Office of Scientific and Technical Information (OSTI.GOV)
W. Lynn Watney; John H. Doveton
GEMINI (Geo-Engineering Modeling through Internet Informatics) is a public-domain web application focused on analysis and modeling of petroleum reservoirs and plays (http://www.kgs.ukans.edu/Gemini/index.html). GEMINI creates a virtual project by ''on-the-fly'' assembly and analysis of on-line data either from the Kansas Geological Survey or uploaded from the user. GEMINI's suite of geological and engineering web applications for reservoir analysis include: (1) petrofacies-based core and log modeling using an interactive relational rock catalog and log analysis modules; (2) a well profile module; (3) interactive cross sections to display ''marked'' wireline logs; (4) deterministic gridding and mapping of petrophysical data; (5) calculation and mappingmore » of layer volumetrics; (6) material balance calculations; (7) PVT calculator; (8) DST analyst, (9) automated hydrocarbon association navigator (KHAN) for database mining, and (10) tutorial and help functions. The Kansas Hydrocarbon Association Navigator (KHAN) utilizes petrophysical databases to estimate hydrocarbon pay or other constituent at a play- or field-scale. Databases analyzed and displayed include digital logs, core analysis and photos, DST, and production data. GEMINI accommodates distant collaborations using secure password protection and authorized access. Assembled data, analyses, charts, and maps can readily be moved to other applications. GEMINI's target audience includes small independents and consultants seeking to find, quantitatively characterize, and develop subtle and bypassed pays by leveraging the growing base of digital data resources. Participating companies involved in the testing and evaluation of GEMINI included Anadarko, BP, Conoco-Phillips, Lario, Mull, Murfin, and Pioneer Resources.« less
LIFTOFF - GEMINI-TITAN (GT)-9A - ATLAS/AGENA - CAPE
1966-05-17
S66-34610 (17 May 1966) --- An Agena Target Vehicle atop its Atlas Launch vehicle is launched from the Kennedy Space Center (KSC) Launch Complex 14 at 10:15 am., May 17, 1966. The Agena was intended as a rendezvous and docking vehicle for the Gemini-9 spacecraft. However, since the Agena failed to achieve orbit, the Gemini-9 mission was postponed. Photo credit: NASA
REVIEW GT-7 MISSION REQUIREMENTS (PRIME CREW)
1965-12-02
S65-56313 (2 Dec. 1965) --- Gemini-7 astronauts James Lovell Jr. (center) and Frank Borman (right) review mission requirements for their Gemini-7 flight. The two astronauts are scheduled for a 14-day mission. On the fifth day, they will attempt a rendezvous with the Gemini-6 spacecraft to be launched nine days later and piloted by astronaut Walter Schirra Jr. and Thomas Stafford. Photo credit: NASA
GEMINI-TITAN (GT)-12 - TRAINING (PRIOR) - MISSION SIMULATOR
1966-09-06
S66-45579 (6 Sept. 1966) --- Astronaut James A. Lovell Jr. (right), prime crew command pilot of the Gemini-12 spaceflight, talks with Burton M. Gifford (left) and Duane K. Mosel (center), both with the Simulation Branch, Flight Crew Support Division. Lovell was preparing to undergo flight training in the Gemini Mission Simulator in Building 5, Mission Simulation and Training Facility. Photo credit: NASA
Personnel discussing Gemini 11 space flight in Mission Control
1966-09-12
S66-52157 (12 Sept. 1966) --- Discussing the Gemini-11 spaceflight in the Mission Control Center are: (left to right) Christopher C. Kraft Jr., (wearing glasses), Director of Flight Operations; Charles W. Mathews (holding phone), Manager, Gemini Program Office; Dr. Donald K. Slayton (center, checked coat), Director of Flight Crew Operations; astronaut William A. Anders, and astronaut John W. Young. Photo credit: NASA
Synthesis and crystal structures of gold nanowires with Gemini surfactants as directing agents.
Xu, Feng; Hou, Hao; Gao, Zhinong
2014-12-15
The preparation of crystalline gold nanowires (NWs) by using gemini surfactants as directing agents through a three-step seed-mediated method is reported. Unlike the nanorods with relatively low aspect ratios (typically below 20) obtained by using cetyltrimethylammonium bromide as a directing agent, the NWs obtained in this investigation can reach up to 4.4 μm, and the largest aspect ratio is calculated to be 210. For this, each of seven different gemini surfactants are utilized as directing agents, and the length and/or aspect ratio of the NWs can be tuned by varying the hydrocarbon chain lengths of the gemini surfactants. Both single and twinned crystalline structures are elucidated by selected-area electron diffraction and high-resolution transmission electron microscopy studies. The use of gemini surfactants not only advances the synthesis of gold nanostructures, but improves the understanding of the growth mechanism for seed-mediated growth. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
GEMINI-TITAN (GT)-12 - EARTH SKY - AGENA ON TETHER - OUTER SPACE
1966-11-13
S66-63517 (13 Nov. 1966) --- The Gulf of California area as seen from the Gemini-12 spacecraft during its 30th revolution of Earth. Baja California Sur is the peninsula on the left. At lower left is the mainland of Mexico. A 100-foot tether line connects the Agena Target Docking Vehicle with the Gemini-12 spacecraft. View is looking south. Photo credit: NASA
GEMINI-TITAN (GT)-V - PILOT - SUITING-UP - CAPE
1965-08-19
S65-46374 (21 Aug. 1965) --- Astronaut Charles Conrad Jr., Gemini-5 pilot, is pictured during suiting up operations on the morning of the flight of Gemini-5. With him is Dr. Eugene Tubbs, a member of the medical team at Cape Kennedy. The mission was originally set for Aug. 19, 1965, but was scrubbed and reset for Aug. 21. Command pilot for the flight is astronaut L. Gordon Cooper Jr.
Gemini 9 configured extravehicular spacesuit assembly
1966-05-01
S66-31019 (May 1966) --- Test subject Fred Spross, Crew Systems Division, wears the Gemini-9 configured extravehicular spacesuit assembly. The legs are covered with Chromel R, which is a cloth woven from stainless steel fibers, used to protect the astronaut and suit from the hot exhaust thrust of the Astronaut Maneuvering Unit (AMU). Astronaut Eugene A. Cernan will wear this spacesuit during his Gemini-9A extravehicular activity (EVA). Photo credit: NASA
1965-12-15
S65-59961 (15 Dec. 1965) --- Astronaut Thomas P. Stafford, pilot, is pictured in the Gemini-6 spacecraft in the White Room atop Pad 19 prior to the closing of the hatches during the Gemini-6 prelaunch countdown. In the background (partially out of view) is astronaut Walter M. Schirra Jr., command pilot. Photo credit: NASA or National Aeronautics and Space Administration
ASTRONAUT SCOTT, DAVID R. - INTERIOR - WATER EGRESS TRAINING (GEMINI-TITAN [GT]-8 PRIME CREW) - MSC
1966-01-05
S66-15743 (5 Jan. 1966) --- Astronaut David R. Scott, pilot of the Gemini-8 prime crew, undergoes water egress training in a special tank in building 260A at the Manned Spacecraft Center (MSC), Houston, Texas. An MSC swimmer assists in the training exercise. A boilerplate model of a Gemini spacecraft floats in the water beside Scott. Photo credit: NASA
Air, telescope, and instrument temperature effects on the Gemini Planet Imager’s image quality
NASA Astrophysics Data System (ADS)
Tallis, Melisa; Bailey, Vanessa P.; Macintosh, Bruce; Hayward, Thomas L.; Chilcote, Jeffrey K.; Ruffio, Jean-Baptiste; Poyneer, Lisa A.; Savransky, Dmitry; Wang, Jason J.; GPIES Team
2018-01-01
We present results from an analysis of air, telescope, and instrument temperature effects on the Gemini Planet Imager’s (GPI) image quality. GPI is a near-infrared, adaptive optics-fed, high-contrast imaging instrument at the Gemini South telescope, designed to directly image and characterize exoplanets and circumstellar disks. One key metric for instrument performance is “contrast,” which quantifies the sensitivity of an image in terms of the flux ratio of the noise floor vs. the primary star. Very high contrast signifies that GPI could succeed at imaging a dim, close companion around the primary star. We examine relationships between multiple temperature sensors placed on the instrument and telescope vs. image contrast. These results show that there is a strong correlation between image contrast and the presence of temperature differentials between the instrument and the temperature outside the dome. We discuss potential causes such as strong induced dome seeing or optical misalignment due to thermal gradients. We then assess the impact of the current temperature control and ventilation strategy and discuss potential modifications.
Sharma, Vishnu D; Aifuwa, Eronmwon O; Heiney, Paul A; Ilies, Marc A
2013-09-01
Pyridinium gemini surfactants possess a soft charge, a high charge/mass ratio and a high molecular flexibility - all key parameters that recommend their use in synthetic gene delivery systems with in vitro and in vivo efficiency. In present study we generated a DNA delivery system through interfacial engineering of pyridinium gemini surfactants at the level of linker, hydrophobic chains and counterions. The self-assembling of the pyridinium amphiphiles and the physicochemical properties of the resultant supra-molecular assemblies were studied in bulk and in solution through a combination of techniques that included DSC, X-ray diffraction, polarized microscopy, CMC, dynamic light scattering and zeta potential measurements. We assessed the impact of different structural elements and formulation parameters of these pyridinium amphiphiles on their DNA compaction properties, transfection efficiency, cytotoxicity, in a complete structure-activity relationship study. This interfacial engineering process generated transfection systems with reduced cytotoxicity and high transfection efficiency in media containing elevated levels of serum that mimic the in vivo conditions. Copyright © 2013 Elsevier Ltd. All rights reserved.
Gemini 8.2-m primary mirror no. 1 polishing
NASA Astrophysics Data System (ADS)
Cayrel, Marc; Beraud, P.; Paseri, Jacques; Dromas, E.
1998-08-01
The 8-m class primary mirrors of the GEMINI Telescopes are thin ULE menisci actively supported. The two mirror blanks are produced by CORNING, the optical figuring, manufacturing and assembling of interfaces are done by REOSC. REOSC is as well in charge of the transportation of the mirror blanks from CORNING to REOSC, and of the shipment of the finished optics to Hawaii and to Chile. The mirror assembly requirements are summarized, the manufacturing and testing methods are addressed. REOSC had to design and manufacture a dedicated active supporting system, representative of the one used at the telescope level. Its design and performance are presented. The manufacturing steps undertaken at REOSC and the results achieved are then detailed: mirror blank surface generating and grinding, polishing, testing. The current status of the mirrors is finally presented.
Astronaut Gene Cernan poses in front of Gemini Mission Simulator
1966-08-09
S66-32698 (17 June 1966) --- Astronaut Eugene A. Cernan discusses his Gemini-9A extravehicular activity before a gathering of news media representatives in the MSC auditorium. In the background is an Astronaut Maneuvering Unit (AMU) mock-up mounted in a mock-up of a Gemini spacecraft adapter equipment section. Astronauts Cernan and Thomas P. Stafford completed their three-day mission in space on June 6, 1966. Photo credit: NASA
ASTRONAUT JAMES A. LOVELL, JR. - MEDICAL - PREFLIGHT (GEMINI-TITAN [GT]-7) - EYES EXAMINED - CAPE
1965-12-02
S65-66703 (18 Dec. 1965) --- Astronaut James A. Lovell Jr., pilot of the National Aeronautics and Space Administration's Gemini-7 spaceflight, undergoes an eye examination during a postflight medical checkup aboard the aircraft carrier USS Wasp. Gemini-7 splashed down in the western Atlantic recovery area at 9:05 a.m. (EST) Dec. 16, 1965, after a 14-day mission in space. Photo credit: NASA
The Gemini-South MCAO operational model: insights on a new era of telescope operation
NASA Astrophysics Data System (ADS)
Trancho, Gelys; Bec, Matthieu; Artigau, Etienne; d'Orgeville, Celine; Gratadour, Damien; Rigaut, Francois J.; Walls, Brian
2008-07-01
The Gemini Observatory is implementing a Multi-Conjugate Adaptive Optics (MCAO) system as a facility instrument for the Gemini South telescope (GeMS). The system will include 5 Laser Guide Stars, 3 Natural Guide Stars, and 3 deformable mirrors, optically conjugated at different altitudes, to achieve near-uniform atmospheric compensation over a one arc minute square field of view. This setup implies some level of operational complexity. In this paper we describe how GeMS will be integrated into the flow of Gemini operations, from the observing procedures necessary to execute the programs in the queue (telescope control software, observing tools, sequence executor) to the safety implementation needed such as spotters/ASCAM, space command and laser traffic control software.
VizieR Online Data Catalog: PTF obs. of a precursor to SNHunt 275 2015 May event (Ofek+, 2016)
NASA Astrophysics Data System (ADS)
Ofek, E. O.; Cenko, S. B.; Shaviv, N. J.; Duggan, G.; Strotjohann, N.-L.; Rubin, A.; Kulkarni, S. R.; Gal-Yam, A.; Sullivan, M.; Cao, Y.; Nugent, P. E.; Kasliwal, M. M.; Sollerman, J.; Fransson, C.; Filippenko, A. V.; Perley, D. A.; Yaron, O.; Laher, R.
2016-08-01
The Palomar Transient Factory (PTF and iPTF; Law et al. 2009PASP..121.1395L; Rau et al. 2009PASP..121.1334R), using the 48inch Oschin Schmidt telescope, observed the field of SNHunt 275 starting in 2009 March. On 2013 December 12, PTF detected a new source at the location of the event, and the transient was named PTF 13efv (see Figure 1). Three images obtained between 2014 January 23 and April 25 were used as a reference. The PTF R-band photometry is listed in Table1. Most of the optical spectra were obtained with the Low Resolution Imaging Spectrometer (LRIS) on the Keck I 10m telescope, although a few spectra were also taken with the DEep Imaging Multi-Object Spectrograph (DEIMOS) on the Keck II 10m telescope, the Kast spectrograph on the Shane 3m telescope at Lick Observatory, and the Gemini-North Multiobject Spectrograph (GMOS) on the 8m Gemini-N telescope. The first spectrum was obtained during the 2013 December outburst. We used the Swift/UVOT observations of SNHunt 275, since 2008, to construct the bolometric light curve of the transient. The log of Swift-XRT observations, along with the source and background X-ray counts in the individual observations, is given in Table 5. (3 data files).
Star Cluster Population in NGC7727
NASA Astrophysics Data System (ADS)
Trancho, G.; Miller, B. W.; Schweizer, F.; Whitmore, B.
2004-12-01
We present observations of the merger NGC7727 taken in the optical with HST and in the K-band with with Gemini South in excellent seeing. Comparing the optical data with Monte-Carlo simulations (Whitmore et al. 1997) suggests the presence of an intermediate-age population, but this is not conclusive due to the age/metallicity degeneracy in optical colours. Therefore, we have obtained images in Ks with FLAMINGOS-I on Gemini South since the V-I vs. V-Ks diagram is an excellent separator of age and metallicity. Comparing the data with Bruzual & Charlot (2001) models confirms the presence of an intermediate-age population (between 1-2 Gyr) and, surprisingly, a lack of old, metal-poor clusters.
GT-7 RECOVERY - BORMAN, FRANK - ASTRONAUT - MISC.
1965-12-18
S66-15463 (18 Dec. 1965) --- Astronaut Frank Borman, command pilot of the National Aeronautics and Space Administration's 14-day Gemini-7 spaceflight, is hoisted from the water by a recovery helicopter from the aircraft carrier USS Wasp. Gemini-7 splashed down in the western Atlantic recovery area at 9:05 a.m. (EST), Dec. 18, 1965, to conclude the record-breaking mission in space. Astronaut James A. Lovell Jr. is the Gemini-7 pilot. Photo credit: NASA
2012-02-17
Project Gemini: On Jan. 3, 1962, NASA announced the advanced Mercury Mark II project had been named "Gemini." After 12 missions – 2 uncrewed and 10 crewed – Project Gemini ended Nov. 15, 1966, following a nearly four-day, 59 orbit-flight. Its achievements included long-duration spaceflight, rendezvous and docking of two spacecraft in Earth orbit, extravehicular activity, and precision-controlled re-entry and landing of the spacecraft. Poster designed by Kennedy Space Center Graphics Department/Greg Lee. Credit: NASA
Requirements management for Gemini Observatory: a small organization with big development projects
NASA Astrophysics Data System (ADS)
Close, Madeline; Serio, Andrew; Cordova, Martin; Hardie, Kayla
2016-08-01
Gemini Observatory is an astronomical observatory operating two premier 8m-class telescopes, one in each hemisphere. As an operational facility, a majority of Gemini's resources are spent on operations however the observatory undertakes major development projects as well. Current projects include new facility science instruments, an operational paradigm shift to full remote operations, and new operations tools for planning, configuration and change control. Three years ago, Gemini determined that a specialized requirements management tool was needed. Over the next year, the Gemini Systems Engineering Group investigated several tools, selected one for a trial period and configured it for use. Configuration activities including definition of systems engineering processes, development of a requirements framework, and assignment of project roles to tool roles. Test projects were implemented in the tool. At the conclusion of the trial, the group determined that the Gemini could meet its requirements management needs without use of a specialized requirements management tool, and the group identified a number of lessons learned which are described in the last major section of this paper. These lessons learned include how to conduct an organizational needs analysis prior to pursuing a tool; caveats concerning tool criteria and the selection process; the prerequisites and sequence of activities necessary to achieve an optimum configuration of the tool; the need for adequate staff resources and staff training; and a special note regarding organizations in transition and archiving of requirements.
Novel gemini cationic lipids with carbamate groups for gene delivery
Zhao, Yi-Nan; Qureshi, Farooq; Zhang, Shu-Biao; Cui, Shao-Hui; Wang, Bing; Chen, Hui-Ying; Lv, Hong-Tao; Zhang, Shu-Fen; Huang, Leaf
2014-01-01
To obtain efficient non-viral vectors, a series of Gemini cationic lipids with carbamate linkers between headgroups and hydrophobic tails were synthesized. They have the hydrocarbon chains of 12, 14, 16 and 18 carbon atoms as tails, designated as G12, G14, G16 and G18, respectively. These Gemini cationic lipids were prepared into cationic liposomes for the study of the physicochemical properties and gene delivery. The DNA-bonding ability of these Gemini cationic liposomes was much better than their mono-head counterparts (designated as M12, M14, M16 and M18, respectively). In the same series of liposomes, bonding ability declined with an increase in tail length. They were tested for their gene-transferring capabilities in Hep-2 and A549 cells. They showed higher transfection efficiency than their mono-head counterparts and were comparable or superior in transfection efficiency and cytotoxicity to the commercial liposomes, DOTAP and Lipofectamine 2000. Our results convincingly demonstrate that the gene-transferring capabilities of these cationic lipids depended on hydrocarbon chain length. Gene transfection efficiency was maximal at a chain length of 14, as G14 can silence about 80 % of luciferase in A549 cells. Cell uptake results indicate that Gemini lipid delivery systems could be internalised by cells very efficiently. Thus, the Gemini cationic lipids could be used as synthetic non-viral gene delivery carriers for further study. PMID:25045521
The Optical Counterpart of M101 ULX-1
NASA Technical Reports Server (NTRS)
Kuntz, K. D.; Gruendi, Robert A.; Chu, You-Hua; Chen, C.-H. Rosie; Still, Martin; Mukai, Koji; Musuotzky, Richard F.
2004-01-01
We have identified the optical counterpart of the Ultra-Luminous X-ray source Ml0l ULX-1 (CX- OKM101 J140332.74+542102), by comparing HST ACS images with Chandra ACIS-S images. The optical counterpart has V= 23.75 and colours consistent with those for a mid-B supergiant. Archival WFPC2 observations show that the source brightness is constant to within approximately 0.1 mag. The physical association of this source with the ULX is confirmed by Gemini GMOS spectroscopic observations which show spatially unresolved He II lambda4686 and He I lambda5876 emission. These results suggest that M10l ULX-1 is a HMXB but deep spectroscopic monitoring observations are needed to determine the detailed properties of this system.
The Near-Earth Encounter of 2005 YU55: Thermal Infrared Observations from Gemini North
NASA Technical Reports Server (NTRS)
Lim, Lucy F.; Emery, Joshua P.; Moskovitz, Nicholas A.; Granvik, Mikael
2012-01-01
As part of a multi-observatory campaign to observe 2005 YU55 during its November 2011 encounter with the Earth, thermal infrared photometry and spectroscopy (7.9- 14 and 18-22 micron) were conducted using the Michelle instrument at Gemini North. Reduction of the 8.8 flm photometry and the spectroscopy from UT Nov-IO as well as of all the Gemini data from UT Nov-9 is in progress. Results will be discussed.
Radiation dosimetry for the Gemini program
NASA Technical Reports Server (NTRS)
Richmond, R. G.
1972-01-01
The principal source of radiation for low-earth-orbit, low inclination space flights is in the area of the South Atlantic magnetic anomaly. None of the Gemini dose measurements reported in the paper are of high enough intensity to be considered hazardous. There is a trend toward larger doses as missions are flown higher and longer. Extended orbital operations between 1400 and 4400 kilometers would encounter high interior radiation levels. Pronounced spacecraft geometry effects have been measured in manned spacecraft. Instrumentation for radiation measurements on Gemini spacecraft is described.
Spatial Distribution of Star Formation in High Redshift Galaxies
NASA Astrophysics Data System (ADS)
Cunnyngham, Ian; Takamiya, M.; Willmer, C.; Chun, M.; Young, M.
2011-01-01
Integral field unit spectroscopy taken of galaxies with redshifts between 0.6 and 0.8 utilizing Gemini Observatory’s GMOS instrument were used to investigate the spatial distribution of star-forming regions by measuring the Hβ and [OII]λ3727 emission line fluxes. These galaxies were selected based on the strength of Hβ and [OII]λ3727 as measured from slit LRIS/Keck spectra. The process of calibrating and reducing data into cubes -- possessing two spatial dimensions, and one for wavelength -- was automated via a custom batch script using the Gemini IRAF routines. Among these galaxies only the bluest sources clearly show [OII] in the IFU regardless of total galaxy luminosity. The brightest galaxies lack [OII] emission and it is posited that two different modes of star formation exist among this seemingly homogeneous group of z=0.7 star-forming galaxies. In order to increase the galaxy sample to include redshifts from 0.3 to 0.9, public Gemini IFU data are being sought. Python scripts were written to mine the Gemini Science Archive for candidate observations, cross-reference the target of these observations with information from the NASA Extragalactic Database, and then present the resultant database in sortable, searchable, cross-linked web-interface using Django to facilitate navigation. By increasing the sample, we expect to characterize these two different modes of star formation which could be high-redshift counterparts of the U/LIRGs and dwarf starburst galaxies like NGC 1569/NGC 4449. The authors acknowledge funds provided by the National Science Foundation (AST 0909240).
The optical design of GMOX: a next-generation instrument concept for Gemini
NASA Astrophysics Data System (ADS)
Barkhouser, Robert; Robberto, Massimo; Smee, Stephen A.; Ninkov, Zoran; Gennaro, Mario; Heckman, Timothy
2016-08-01
We present the optical design of GMOX, the Gemini Multi-Object eXtra-wide-band spectrograph. GMOX was selected as part of the Gemini Instrument Feasibility Study to develop capabilities and requirements for the next facility instrument (Gen4#3) for the observatory. We envision GMOX covering the entire optical/near-IR wavelength range accessible from the ground, from 3500 Å in the U band up to 2.4 μm in the K band, with nominal resolving power R≃5,000. To maximize efficiency, the bandpass is split into three spectrograph arms - blue, red, and near-infrared - with the near-infrared arm further split into three channels covering the Y+J, H, and K bands. At the heart of each arm is a Digital Micromirror Device (DMD) serving as a programmable slit array. This technology will enable GMOX to simultaneously acquire hundreds of spectra of faint sources in crowded fields with unparalleled spatial resolution, optimally adapting to both seeing-limited and diffraction limited conditions provided by ALTAIR and GeMS at Gemini North and South, respectively. Fed by GeMS at f/33, GMOX can synthesize slits as small as 40 mas (corresponding to a single HST/WFC3 CCD pixel) over its entire 85"x45" field of view. With either ALTAIR or the native telescope focal ratio of f/16, both the slit and field sizes double. In this paper we discuss the conceptual optical design of GMOX including, for each arm: the pre-slit optics, DMD slit array, off-axis Schmidt collimator, VPH grating, and refractive spectrograph and slit-viewing cameras.
Cationic gemini surfactant-assisted synthesis of hollow Au nanostructures by stepwise reductions.
Wang, Wentao; Han, Yuchun; Tian, Maozhang; Fan, Yaxun; Tang, Yongqiang; Gao, Mingyuan; Wang, Yilin
2013-06-26
A novel synthetic approach was developed for creating versatile hollow Au nanostructures by stepwise reductions of Au(III) upon the use of cationic gemini surfactant hexamethylene-1,6-bis(dodecyl dimethylammonium bromide) (C12C6C12Br2) as a template agent. It was observed that the Au(I) ions obtained from the reduction of Au(III) by ascorbic acid can assist the gemini surfactant to form vesicles, capsule-like, and tube-like aggregates that subsequently act as soft templates for hollow Au nanostructures upon further reduction of Au(I) to Au(0) by NaBH4. It was demonstrated that the combination of C12C6C12Br2 and Au(I) plays a key role in regulating the structure of the hollow precursors not only because C12C6C12Br2 has a stronger aggregation ability in comparison with its single chain counterpart but also because the electrostatic repulsion between head groups of C12C6C12Br2 is greatly weakened after Au(III) is converted to Au(I), which is in favor of the construction of vesicles, capsule-like, and tube-like aggregates. Compared with solid Au nanospheres, the resultant hollow nanostructures exhibit enhanced electrocatalytic activities in methanol oxidation, following the order of elongated nanocapsule > nanocapsule > nanosphere. Benefiting from balanced interactions between the gemini surfactant and Au(I), this soft-template method may present a facile and versatile approach for the controlled synthesis of Au nanostructures potentially useful for fuel cells and other Au nanodevices.
Characterizing 51 Eri b from 1 to 5 μm: A Partly Cloudy Exoplanet
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rajan, Abhijith; Rameau, Julien; Rosa, Robert J. De
Here, we present spectrophotometry spanning 1–5 μm of 51 Eridani b, a 2–10more » $${M}_{\\mathrm{Jup}}$$ planet discovered by the Gemini Planet Imager Exoplanet Survey. In this study, we present new K1 (1.90–2.19 μm) and K2 (2.10–2.40 μm) spectra taken with the Gemini Planet Imager as well as an updated L P (3.76 μm) and new M S (4.67 μm) photometry from the NIRC2 Narrow camera. The new data were combined with J (1.13–1.35 μm) and H (1.50–1.80 μm) spectra from the discovery epoch with the goal of better characterizing the planet properties. The 51 Eri b photometry is redder than field brown dwarfs as well as known young T-dwarfs with similar spectral type (between T4 and T8), and we propose that 51 Eri b might be in the process of undergoing the transition from L-type to T-type. We used two complementary atmosphere model grids including either deep iron/silicate clouds or sulfide/salt clouds in the photosphere, spanning a range of cloud properties, including fully cloudy, cloud-free, and patchy/intermediate-opacity clouds. The model fits suggest that 51 Eri b has an effective temperature ranging between 605 and 737 K, a solar metallicity, and a surface gravity of log(g) = 3.5–4.0 dex, and the atmosphere requires a patchy cloud atmosphere to model the spectral energy distribution (SED). From the model atmospheres, we infer a luminosity for the planet of –5.83 to –5.93 ($$\\mathrm{log}L/{L}_{\\odot }$$), leaving 51 Eri b in the unique position of being one of the only directly imaged planets consistent with having formed via a cold-start scenario. Comparisons of the planet SED against warm-start models indicate that the planet luminosity is best reproduced by a planet formed via core accretion with a core mass between 15 and 127 $${M}_{\\oplus }$$.« less
Characterizing 51 Eri b from 1 to 5 μm: A Partly Cloudy Exoplanet
Rajan, Abhijith; Rameau, Julien; Rosa, Robert J. De; ...
2017-06-16
Here, we present spectrophotometry spanning 1–5 μm of 51 Eridani b, a 2–10more » $${M}_{\\mathrm{Jup}}$$ planet discovered by the Gemini Planet Imager Exoplanet Survey. In this study, we present new K1 (1.90–2.19 μm) and K2 (2.10–2.40 μm) spectra taken with the Gemini Planet Imager as well as an updated L P (3.76 μm) and new M S (4.67 μm) photometry from the NIRC2 Narrow camera. The new data were combined with J (1.13–1.35 μm) and H (1.50–1.80 μm) spectra from the discovery epoch with the goal of better characterizing the planet properties. The 51 Eri b photometry is redder than field brown dwarfs as well as known young T-dwarfs with similar spectral type (between T4 and T8), and we propose that 51 Eri b might be in the process of undergoing the transition from L-type to T-type. We used two complementary atmosphere model grids including either deep iron/silicate clouds or sulfide/salt clouds in the photosphere, spanning a range of cloud properties, including fully cloudy, cloud-free, and patchy/intermediate-opacity clouds. The model fits suggest that 51 Eri b has an effective temperature ranging between 605 and 737 K, a solar metallicity, and a surface gravity of log(g) = 3.5–4.0 dex, and the atmosphere requires a patchy cloud atmosphere to model the spectral energy distribution (SED). From the model atmospheres, we infer a luminosity for the planet of –5.83 to –5.93 ($$\\mathrm{log}L/{L}_{\\odot }$$), leaving 51 Eri b in the unique position of being one of the only directly imaged planets consistent with having formed via a cold-start scenario. Comparisons of the planet SED against warm-start models indicate that the planet luminosity is best reproduced by a planet formed via core accretion with a core mass between 15 and 127 $${M}_{\\oplus }$$.« less
Constraining the Type Ia Supernova Progenitor: The Search for Hydrogen in Nebular Spectra
NASA Astrophysics Data System (ADS)
Leonard, Douglas C.
2007-12-01
Despite intense scrutiny, the progenitor system(s) that gives rise to Type Ia supernovae remains unknown. The favored theory invokes a carbon-oxygen white dwarf accreting hydrogen-rich material from a close companion until a thermonuclear runaway ensues that incinerates the white dwarf. However, simulations resulting from this single-degenerate, binary channel demand the presence of low-velocity Hα emission in spectra taken during the late nebular phase, since a portion of the companion's envelope becomes entrained in the ejecta. This hydrogen has never been detected, but has only rarely been sought. Here we present results from a campaign to obtain deep, nebular-phase spectroscopy of nearby Type Ia supernovae, and include multiepoch observations of two events: SN 2005am (slightly subluminous) and SN 2005cf (normally bright). No Hα emission is detected in the spectra of either object. An upper limit of 0.01 Msolar of solar abundance material in the ejecta is established from the models of Mattila et al., which, when coupled with the mass-stripping simulations of Marietta et al. and Meng et al., effectively rules out progenitor systems for these supernovae with secondaries close enough to the white dwarf to be experiencing Roche lobe overflow at the time of explosion. Alternative explanations for the absence of Hα emission, along with suggestions for future investigations necessary to confidently exclude them as possibilities, are critically evaluated. Some of the data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. Additional observations were obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the Particle Physics and Astronomy Research Council (United Kingdom), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), CNPq (Brazil), and CONICET (Argentina).
Gemini Capsule and Rendezvous Docking Simulator
1962-12-19
Practicing with a full-scale model of the Gemini Capsule in Langley's Rendezvous Docking Simulator. -- Caption and photograph published in Winds of Change, 75th Anniversary NASA publication, (page 89), by James Schultz.
1965-03-18
S65-20641 (1965) --- Astronauts John W. Young (left), pilot, and Virgil I. Grissom, command pilot, for the Gemini-Titan 3 flight, are shown leaving the launch pad after simulations in the Gemini-3 spacecraft.
The relationship between appetite and food preferences in British and Australian children.
Fildes, Alison; Mallan, Kimberley M; Cooke, Lucy; van Jaarsveld, Cornelia H M; Llewellyn, Clare H; Fisher, Abigail; Daniels, Lynne
2015-09-17
Appetitive traits and food preferences are key determinants of children's eating patterns but it is unclear how these behaviours relate to one another. This study explores relationships between appetitive traits and preferences for fruits and vegetables, and energy dense, nutrient poor (noncore) foods in two distinct samples of Australian and British preschool children. This study reports secondary analyses of data from families participating in the British GEMINI cohort study (n = 1044) and the control arm of the Australian NOURISH RCT (n = 167). Food preferences were assessed by parent-completed questionnaire when children were aged 3-4 years and grouped into three categories; vegetables, fruits and noncore foods. Appetitive traits; enjoyment of food, food responsiveness, satiety responsiveness, slowness in eating, and food fussiness were measured using the Children's Eating Behaviour Questionnaire when children were 16 months (GEMINI) or 3-4 years (NOURISH). Relationships between appetitive traits and food preferences were explored using adjusted linear regression analyses that controlled for demographic and anthropometric covariates. Vegetable liking was positively associated with enjoyment of food (GEMINI; β = 0.20 ± 0.03, p < 0.001, NOURISH; β = 0.43 ± 0.07, p < 0.001) and negatively related to satiety responsiveness (GEMINI; β = -0.19 ± 0.03, p < 0.001, NOURISH; β = -0.34 ± 0.08, p < 0.001), slowness in eating (GEMINI; β = -0.10 ± 0.03, p = 0.002, NOURISH; β = -0.30 ± 0.08, p < 0.001) and food fussiness (GEMINI; β = -0.30 ± 0.03, p < 0.001, NOURISH; β = -0.60 ± 0.06, p < 0.001). Fruit liking was positively associated with enjoyment of food (GEMINI; β = 0.18 ± 0.03, p < 0.001, NOURISH; β = 0.36 ± 0.08, p < 0.001), and negatively associated with satiety responsiveness (GEMINI; β = -0.13 ± 0.03, p < 0.001, NOURISH; β = -0.24 ± 0.08, p = 0.003), food fussiness (GEMINI; β = -0.26 ± 0.03, p < 0.001, NOURISH; β = -0.51 ± 0.07, p < 0.001) and slowness in eating (GEMINI only; β = -0.09 ± 0.03, p = 0.005). Food responsiveness was unrelated to liking for fruits or vegetables in either sample but was positively associated with noncore food preference (GEMINI; β = 0.10 ± 0.03, p = 0.001, NOURISH; β = 0.21 ± 0.08, p = 0.010). Appetitive traits linked with lower obesity risk were related to lower liking for fruits and vegetables, while food responsiveness, a trait linked with greater risk of overweight, was uniquely associated with higher liking for noncore foods.
Cool White Dwarfs Found in the UKIRT Infrared Deep Sky Survey
NASA Astrophysics Data System (ADS)
Leggett, S. K.; Lodieu, N.; Tremblay, P.-E.; Bergeron, P.; Nitta, A.
2011-07-01
We present the results of a search for cool white dwarfs in the United Kingdom InfraRed Telescope (UKIRT) Infrared Deep Sky Survey (UKIDSS) Large Area Survey (LAS). The UKIDSS LAS photometry was paired with the Sloan Digital Sky Survey to identify cool hydrogen-rich white dwarf candidates by their neutral optical colors and blue near-infrared colors, as well as faint reduced proper motion magnitudes. Optical spectroscopy was obtained at Gemini Observatory and showed the majority of the candidates to be newly identified cool degenerates, with a small number of G- to K-type (sub)dwarf contaminants. Our initial search of 280 deg2 of sky resulted in seven new white dwarfs with effective temperature T eff ≈ 6000 K. The current follow-up of 1400 deg2 of sky has produced 13 new white dwarfs. Model fits to the photometry show that seven of the newly identified white dwarfs have 4120 K <=T eff <= 4480 K, and cooling ages between 7.3 Gyr and 8.7 Gyr; they have 40 km s-1 <= v tan <= 85 km s-1 and are likely to be thick disk 10-11 Gyr-old objects. The other half of the sample has 4610 K <=T eff <= 5260 K, cooling ages between 4.3 Gyr and 6.9 Gyr, and 60 km s-1 <= v tan <= 100 km s-1. These are either thin disk remnants with unusually high velocities, or lower-mass remnants of thick disk or halo late-F or G stars.
Diagrams of Spacecraft Reaction Control System (RCS) Function
1964-01-13
S64-03506 (1964) --- Diagrams shows Gemini spacecraft functions of the thrusters in the Gemini spacecraft's re-entry control system. Thrusters may be fired in various combinations to cause yaw, roll and pitch.
A comparison of Gemini and ERTS imagery obtained over southern Morocco
NASA Technical Reports Server (NTRS)
Blodget, H. W.; Anderson, A. T.
1973-01-01
A mosaic constructed from three ERTS MSS band 5 images enlarged to 1:500,000 compares favorably with a similar scale geologic map of southern Morocco, and a near-similar scale Gemini 5 photo pair. A comparative plot of lineations and generalized geology on the three formats show that a significantly greater number of probable fractures are visible on the ERTS imagery than on the Gemini photography, and that both orbital formats show several times more lineaments than were previously mapped. A plot of mineral occurrences on the structural overlays indicates that definite structure-mineralization relationships exist; this finding is used to define underdeveloped areas which are prospective for mineralization. More detailed mapping is possible using MSS imagery than on Gemini 5 photographs, and in addition, the ERTS format is not restricted to limited coverage.
Differential speckle and wide-field imaging for the Gemini-North and WIYN telescopes
NASA Astrophysics Data System (ADS)
Scott, Nicholas J.; Howell, Steve B.; Horch, Elliott P.
2016-07-01
Two new instruments are currently being built for the Gemini-North and WIYN telescopes. They are based on the existing DSSI (Differential Speckle Survey Instrument), but the new dual-channel instruments will have both speckle and "wide-field" imaging capabilities. Nearly identical copies of the instrument will be installed as a public access permanent loan at the Gemini-N and WIYN telescopes. Many exoplanet targets will come from the NASA K2 and TESS missions. The faint limiting magnitude, for speckle observations, will remain around 16 to 17th magnitude depending on observing conditions, while wide-field, high speed imaging should be able to go to 21+. For Gemini, the instrument will be remotely operable from either the mid-level facility at Hale Pohaku or the remote operations base in Hilo.
A Gemini snapshot survey for double degenerates
NASA Astrophysics Data System (ADS)
Kilic, Mukremin; Brown, Warren R.; Gianninas, A.; Curd, Brandon; Bell, Keaton J.; Allende Prieto, Carlos
2017-11-01
We present the results from a Gemini snapshot radial-velocity survey of 44 low-mass white-dwarf candidates selected from the Sloan Digital Sky Survey (SDSS) spectroscopy. To find sub-hour orbital period binary systems, our time-series spectroscopy had cadences of 2-8 min over a period of 20-30 min. Through follow-up observations at Gemini and the MMT, we identify four double-degenerate binary systems with periods ranging from 53 min to 7 h. The shortest period system, SDSS J123549.88+154319.3, was recently identified as a sub-hour period detached binary by Breedt and collaborators. Here, we refine the orbital and physical parameters of this system. High-speed and time-domain survey photometry observations do not reveal eclipses or other photometric effects in any of our targets. We compare the period distribution of these four systems with the orbital period distribution of known double white dwarfs; the median period decreases from 0.64 to 0.24 d for M = 0.3-0.5 M⊙ to M < 0.3 M⊙ white dwarfs. However, we do not find a statistically significant correlation between the orbital period and white-dwarf mass.
2004-05-01
KENNEDY SPACE CENTER, FLA. -- Former astronaut Jim Lovell acknowledges the applause as he is introduced as a previous inductee into the U.S. Astronaut Hall of Fame. He and other Hall of Fame members were present for the induction of five new space program heroes into the U.S. Astronaut Hall of Fame: Richard O. Covey, commander of the Hubble Space Telescope repair mission; Norman E. Thagard, the first American to occupy Russia’s Mir space station; the late Francis R. "Dick" Scobee, commander of the ill-fated 1986 Challenger mission; Kathryn D. Sullivan, the first American woman to walk in space; and Frederick D. Gregory, the first African-American to command a space mission and the current NASA deputy administrator. Lovell piloted Gemini 7, commanded Gemini 12, orbited the Moon on Apollo 8 and commanded the aborted Apollo 13 moon flight. The induction ceremony was held at the Apollo/Saturn V Center at KSC. The U.S. Astronaut Hall of Fame opened in 1990 to provide a place where space travelers could be remembered for their participation and accomplishments in the U.S. space program. The five inductees join 52 previously honored astronauts from the ranks of the Gemini, Apollo, Skylab, Apollo-Soyuz, and Space Shuttle programs.
GeMS: Gemini Mcao System: current status and commissioning plans
NASA Astrophysics Data System (ADS)
Boccas, Maxime; Rigaut, François; Gratadour, Damien; d'Orgeville, Céline; Bec, Matthieu; Daruich, Felipe; Perez, Gabriel; Arriagada, Gustavo; Bombino, Stacy; Carter, Chris; Cavedoni, Chas; Collao, Fabian; Collins, Paul; Diaz, Pablo; Ebbers, Angelic; Galvez, Ramon; Gausachs, Gaston; Hardash, Steve; James, Eric; Karewicz, Stan; Lazo, Manuel; Maltes, Diego; Mouser, Ron; Rogers, Rolando; Rojas, Roberto; Sheehan, Michael; Trancho, Gelys; Vergara, Vicente; Vucina, Tomislav
2008-07-01
The Gemini Multi-Conjugate Adaptive Optics project was launched in April 1999 to become the Gemini South AO facility in Chile. The system includes 5 laser guide stars, 3 natural guide stars and 3 deformable mirrors optically conjugated at 0, 4.5 and 9km to achieve near-uniform atmospheric compensation over a 1 arc minute square field of view. Sub-contracted systems with vendors were started as early as October 2001 and were all delivered by July 2007, but for the 50W laser (due around September 2008). The in-house development began in January 2006, and is expected to be completed by the end of 2008 to continue with integration and testing (I&T) on the telescope. The on-sky commissioning phase is scheduled to start during the first half of 2009. In this general overview, we will first describe the status of each subsystem with their major requirements, risk areas and achieved performance. Next we will present our plan to complete the project by reviewing the remaining steps through I&T and commissioning on the telescope, both during day-time and at night-time. Finally, we will summarize some management activities like schedules, resources and conclude with some lessons learned.
Off-the-shelf Control of Data Analysis Software
NASA Astrophysics Data System (ADS)
Wampler, S.
The Gemini Project must provide convenient access to data analysis facilities to a wide user community. The international nature of this community makes the selection of data analysis software particularly interesting, with staunch advocates of systems such as ADAM and IRAF among the users. Additionally, the continuing trends towards increased use of networked systems and distributed processing impose additional complexity. To meet these needs, the Gemini Project is proposing the novel approach of using low-cost, off-the-shelf software to abstract out both the control and distribution of data analysis from the functionality of the data analysis software. For example, the orthogonal nature of control versus function means that users might select analysis routines from both ADAM and IRAF as appropriate, distributing these routines across a network of machines. It is the belief of the Gemini Project that this approach results in a system that is highly flexible, maintainable, and inexpensive to develop. The Khoros visualization system is presented as an example of control software that is currently available for providing the control and distribution within a data analysis system. The visual programming environment provided with Khoros is also discussed as a means to providing convenient access to this control.
VizieR Online Data Catalog: z~3-6 protoclusters in the CFHTLS deep fields (Toshikawa+, 2016)
NASA Astrophysics Data System (ADS)
Toshikawa, J.; Kashikawa, N.; Overzier, R.; Malkan, M. A.; Furusawa, H.; Ishikawa, S.; Onoue, M.; Ota, K.; Tanaka, M.; Niino, Y.; Uchiyama, H.
2018-03-01
We made use of publicly available data from the CFHTLS (T0007: Gwyn 2012AJ....143...38G; Hudelot et al. 2012, Cat. II/317), which was obtained with MegaCam mounted at the prime focus of the CFHT. The Deep Fields of the CFHTLS were used in this study, which consist of four independent fields of about 1 deg2 area each (~4 deg2 area in total) observed in the u*, g', r', i', and z' bands. We selected z~3-6 galaxy candidates using the Lyman-break technique (u-, g-, r-, and i-dropout galaxies). We carried out spectroscopic observations using Subaru/FOCAS (Kashikawa et al. 2002PASJ...54..819K), Keck II/DEIMOS (Faber et al. 2003SPIE.4841.1657F), and Gemini-N/GMOS (Hook et al. 2004PASP..116..425H). In these observations, eight protocluster candidates from z~3 to z~6 were observed in total (two at each redshift). All these observations were conducted with Multi-Object Spectroscopy (MOS) mode. (2 data files).
The Gemini Planet Imager: integration and status
NASA Astrophysics Data System (ADS)
Macintosh, Bruce A.; Anthony, Andre; Atwood, Jennifer; Barriga, Nicolas; Bauman, Brian; Caputa, Kris; Chilcote, Jeffery; Dillon, Daren; Doyon, René; Dunn, Jennifer; Gavel, Donald T.; Galvez, Ramon; Goodsell, Stephen J.; Graham, James R.; Hartung, Markus; Isaacs, Joshua; Kerley, Dan; Konopacky, Quinn; Labrie, Kathleen; Larkin, James E.; Maire, Jerome; Marois, Christian; Millar-Blanchaer, Max; Nunez, Arturo; Oppenheimer, Ben R.; Palmer, David W.; Pazder, John; Perrin, Marshall; Poyneer, Lisa A.; Quirez, Carlos; Rantakyro, Frederik; Reshtov, Vlad; Saddlemyer, Leslie; Sadakuni, Naru; Savransky, Dmitry; Sivaramakrishnan, Anand; Smith, Malcolm; Soummer, Remi; Thomas, Sandrine; Wallace, J. Kent; Weiss, Jason; Wiktorowicz, Sloane
2012-09-01
The Gemini Planet Imager is a next-generation instrument for the direct detection and characterization of young warm exoplanets, designed to be an order of magnitude more sensitive than existing facilities. It combines a 1700-actuator adaptive optics system, an apodized-pupil Lyot coronagraph, a precision interferometric infrared wavefront sensor, and a integral field spectrograph. All hardware and software subsystems are now complete and undergoing integration and test at UC Santa Cruz. We will present test results on each subsystem and the results of end-to-end testing. In laboratory testing, GPI has achieved a raw contrast (without post-processing) of 10-6 5σ at 0.4", and with multiwavelength speckle suppression, 2x10-7 at the same separation.
Megajoule Dense Plasma Focus Solid Target Experiments
NASA Astrophysics Data System (ADS)
Podpaly, Y. A.; Falabella, S.; Link, A.; Povilus, A.; Higginson, D. P.; Shaw, B. H.; Cooper, C. M.; Chapman, S.; Bennett, N.; Sipe, N.; Olson, R.; Schmidt, A. E.
2016-10-01
Dense plasma focus (DPF) devices are plasma sources that can produce significant neutron yields from beam into gas interactions. Yield increases, up to approximately a factor of five, have been observed previously on DPFs using solid targets, such as CD2 and D2O ice. In this work, we report on deuterium solid-target experiments at the Gemini DPF. A rotatable target holder and baffle arrangement were installed in the Gemini device which allowed four targets to be deployed sequentially without breaking vacuum. Solid targets of titanium deuteride were installed and systematically studied at a variety of fill pressures, bias voltages, and target positions. Target holder design, experimental results, and comparison to simulations will be presented. Prepared by LLNL under Contract DE-AC52-07NA27344.
Calibrations for a MCAO Imaging System
NASA Astrophysics Data System (ADS)
Hibon, Pascale; B. Neichel; V. Garrel; R. Carrasco
2017-09-01
"GeMS, the Gemini Multi conjugate adaptive optics System installed at the Gemini South telescope (Cerro Pachon, Chile) started to deliver science since the beginning of 2013. GeMS is using the Multi Conjugate AdaptiveOptics (MCAO) technique allowing to dramatically increase the corrected field of view (FOV) compared to classical Single Conjugated Adaptive Optics (SCAO) systems. It is the first sodium-based multi-Laser Guide Star (LGS) adaptive optics system. It has been designed to feed two science instruments: GSAOI, a 4k×4k NIR imager covering 85"×85" with 0.02" pixel scale, and Flamingos-2, a NIR multi-object spectrograph. We present here an overview of the calibrations necessary for reducing and analysing the science datasets obtained with GeMS+GSAOI."
Tehrani-Bagha, A R; Holmberg, K; van Ginkel, C G; Kean, M
2015-07-01
The paper describes synthesis and characterization of a new type of cationic gemini surfactant, which has dodecyl tails and a spacer that contains an ester bond. The nomenclature used to describe the structure is 12Q2OCO1Q12, with Q being a quaternary ammonium group and the numbers indicating the number of methylene or methyl groups. Due to the close proximity to the two quaternary ammonium groups, the ester bond is very stable on the acid side and very labile already at slightly alkaline conditions. The hydrolysis products are two single chain surfactants (i.e. 12Q2OH and 12Q1COOH) which are less surface active than the intact gemini surfactant. 12Q2OCO1Q12 was found to be readily biodegradable, i.e. it gave more than 60% biodegradation after 28 days. This is interesting because similar gemini surfactants but with ester bonds in the tails instead of the spacer, have previously been found not to be readily biodegradable. The gemini surfactant was found to be toxic to aquatic organisms (ErC50 value of 0.27 mg/l), although less toxic than the two hydrolysis products. Copyright © 2014 Elsevier Inc. All rights reserved.
1965-05-01
Food packages for use on the Gemini-Titan 4 (GT-4) flight. Packages include beef and gravy, peaches, strawberry cereal cubes and beef sandwiches. A water gun is used to reconstitute the dehydrated food. MSC, HOUSTON, TX CN
LEAVING PAD - ASTRONAUT JOHN W. YOUNG - TRAINING
1965-03-19
S65-20636 (1965) --- Astronauts John W. Young (left), pilot, and Virgil I. Grissom, command pilot, for the Gemini-Titan 3 flight, are shown leaving the launch pad after simulations in the Gemini-3 spacecraft.
Al-Dulaymi, Mays A; Chitanda, Jackson M; Mohammed-Saeid, Waleed; Araghi, Hessamaddin Younesi; Verrall, Ronald E; Grochulski, Pawel; Badea, Ildiko
2016-09-01
The aim of this work was to elucidate the structure-activity relationship of new peptide-modified gemini surfactant-based carriers. Glycyl-lysine modified gemini surfactants that differ in the length and degree of unsaturation of their alkyl tail were used to engineer DNA nano-assemblies. To probe the optimal nitrogen to phosphate (N/P) ratio in the presence of helper lipid, in vitro gene expression and cell toxicity measurements were carried out. Characterization of the nano-assemblies was accomplished by measuring the particle size and surface charge. Morphological characteristics and lipid organization were studied by small angle X-ray scattering technique. Lipid monolayers were studied using a Langmuir-Blodgett trough. The highest activity of glycyl-lysine modified gemini surfactants was observed with the 16-carbon tail compound at 2.5 N/P ratio, showing a 5- to 10-fold increase in the level of reporter protein compared to the 12 and 18:1 carbon tail compounds. This ratio is significantly lower compared to the previously studied gemini surfactants with alkyl or amino- spacers. In addition, the 16-carbon tail compound exhibited the highest cell viability (85%). This high efficiency is attributed to the lowest critical micelle concentration of the 16-tail gemini surfactant and a balanced packing of the nanoparticles by mixing a saturated and unsaturated lipid together. At the optimal N/P ratio, all nanoparticles exhibited an inverted hexagonal lipid assembly. The results show that the length and nature of the tail of the gemini surfactants play an important role in determining the transgene efficiency of the delivery system. We demonstrated here that the interplay between the headgroup and the nature of tail is specific to each series, thus in the process of rational design, the contribution of the latter should be assessed in the appropriate context.
GEMINI-6 - EARTH-SKY - CANARY ISLANDS - OUTER SPACE
1965-12-16
S65-63150 (16 Dec. 1965) --- Eddies in stratocumulus clouds over the Canary Islands as seen from the Gemini-6 spacecraft during its 14th revolution of Earth. Photo credit: NASA or National Aeronautics and Space Administration
Technicians prepare to close hatches on Gemini 12 spacecraft
NASA Technical Reports Server (NTRS)
1966-01-01
Technicians prepare to close the hatches of the Gemini 12 spacecraft in the White Room atop Pad 19 after insertion of Astronauts James A. Lovell Jr. (leading), command pilot, and Edwin E. Aldrin Jr., pilot.
Technicians close hatches on Gemini 11 spacecraft during countdown
NASA Technical Reports Server (NTRS)
1966-01-01
Technicians in the White Room atop Pad 19 prepare to close hatches on the Gemini 11 spacecraft during prelaunch countdown. Inside the spacecraft are Astronauts Charles Conrad Jr., command pilot, and Richard F. Gordon Jr., pilot.
Florida, Bahama Islands, Cuba as seen from Gemini 12 spacecraft
1966-11-13
S66-63418 (13 Nov. 1966) --- Florida (south half), Bahamas Islands (Andros-Grand Bahamas-Bimini), and Cuba, looking south as seen from Gemini-12 spacecraft on its 15th revolution of Earth. Photo credit: NASA
Food packages for use on the Gemini 4 flight
NASA Technical Reports Server (NTRS)
1965-01-01
Food packages for use on the Gemini 4 flight. Packages include beef and gravy, peaches, strawberry cereal cubes and beef sandwiches. Water gun is used to reconstitute dehydrated food. Scissors are used to open the packages.
Novel fluorinated gemini surfactants with γ-butyrolactone segments.
Kawase, Tokuzo; Okada, Kazuyuki; Oida, Tatsuo
2015-01-01
In this work, novel γ-butyrolactone-type monomeric and dimeric (gemini) surfactants with a semifluoroalkyl group [Rf- (CH2)3-; Rf = C4F9, C6F13, C8F17] as the hydrophobic group were successfully synthesized. Dimethyl malonate was dimerized or connected using Br(CH2)sBr (s = 0, 1, 2, 3) to give tetraesters, and they were bis-allylated. Radical addition of fluoroalkyl using Rf-I and an initiator, i.e., 2,2'-azobisisobutyronitrile for C4F9 or di-t-butyl peroxide for C6F13 and C8F17, was perform at high temperature, with prolonged heating, to obtain bis(semifluoroalkyl)-dilactone diesters. These dilactone diesters were hydrolyzed using KOH/EtOH followed by decarboxylation in AcOH to afford γ-butyrolactonetype gemini surfactants. Common 1 + 1 semifluoroalkyl lactone surfactants were synthesized using the same method. Their surfactant properties [critical micelle concentration (CMC), γCMC, pC20, ΓCMC, and AG] were investigated by measuring the surface tension of the γ-hydroxybutyrate form prepared in aqueous tetrabutylammonium hydroxide solution. As expected, the CMC values of the gemini surfactants were more than one order of magnitude smaller than those of the corresponding 1 + 1 surfactants. Other properties also showed the excellent ability of the gemini structure to reduce the surface tension. These surfactants were easily and quantitatively recovered by acidification. The monomeric surfactant was recovered in the γ-hydroxybutyric acid form, and the gemini surfactant as a mixture of γ-butyrolactone and γ-hydroxybutyric acid forms.
GEMINI-7 - EARTH-SKY VIEW - LIMB - OUTER SPACE
1965-12-07
S65-65257 (4-18 Dec. 1965) --- Sunrise and Earth's limb, as photographed by astronauts Frank Borman and James A. Lovell Jr. during their Earth-orbital 14-day mission in the Gemini-7 (GT-7) spacecraft. Photo credit: NASA
China, India, and Nepal as seen from Gemini 11
1966-09-14
S66-54839 (14 Sept. 1966) --- China, India, and Nepal, looking east, as seen from the Gemini-11 spacecraft during its 37th revolution of Earth. The Great Himalaya Mountain Range is clearly visible. Photo credit: NASA
GEMINI-TITAN (GT)-9 TEST - TRAINING - GULF OF MEXICO
1965-05-20
S65-22656 (14 April 1965) --- The Gemini-Titan 4 prime crew, astronauts Edward H. White II (left), pilot, and James A. McDivitt, command pilot, pictured aboard the NASA Motor Vessel Retriever in the Gulf of Mexico.
Dietician prepares Gemini 7 crew preflight breakfast
1965-12-04
S65-56311 (2 Dec. 1965) --- Kennedy Space Center food specialists prepare an Earth-bound meal for Gemini-7 astronauts. Astronauts' diet is strictly controlled before and during spaceflights to avoid interfering with planned medical experiments. Photo credit: NASA
Food packets for use on the Gemini 3 flight
NASA Technical Reports Server (NTRS)
1965-01-01
Food packets for use on the Gemini 3 flight including dehydrated beef pot roast, bacon and egg bites, toasted bread cubes, orange juice and a wet wipe. Water is being inserted into the pouch of dehydrated food.
Gemini Simulator and Neil Armstrong
1963-11-06
Astronaut Neil Armstrong (left) was one of 14 astronauts, 8 NASA test pilots, and 2 McDonnell test pilots who took part in simulator studies. Armstrong was the first astronaut to participate (November 6, 1963). A.W. Vogeley described the simulator in his paper "Discussion of Existing and Planned Simulators For Space Research," "Many of the astronauts have flown this simulator in support of the Gemini studies and they, without exception, appreciated the realism of the visual scene. The simulator has also been used in the development of pilot techniques to handle certain jet malfunctions in order that aborts could be avoided. In these situations large attitude changes are sometimes necessary and the false motion cues that were generated due to earth gravity were somewhat objectionable; however, the pilots were readily able to overlook these false motion cues in favor of the visual realism." Roy F. Brissenden, noted in his paper "Initial Operations with Langley's Rendezvous Docking Facility," "The basic Gemini control studies developed the necessary techniques and demonstrated the ability of human pilots to perform final space docking with the specified Gemini-Agena systems using only visual references. ... Results... showed that trained astronauts can effect the docking with direct acceleration control and even with jet malfunctions as long as good visual conditions exist.... Probably more important than data results was the early confidence that the astronauts themselves gained in their ability to perform the maneuver in the ultimate flight mission." Francis B. Smith, noted in his paper "Simulators for Manned Space Research," "Some major areas of interest in these flights were fuel requirements, docking accuracies, the development of visual aids to assist alignment of the vehicles, and investigation of alternate control techniques with partial failure modes. However, the familiarization and confidence developed by the astronaut through flying and safely docking the simulator during these tests was one of the major contributions. For example, it was found that fuel used in docking from 200 feet typically dropped from about 20 pounds to 7 pounds after an astronaut had made a few training flights." -- Published in Barton C. Hacker and James M. Grimwood, On the Shoulders of Titans: A History of Project Gemini, NASA SP-4203; A.W. Vogeley, "Discussion of Existing and Planned Simulators For Space Research," Paper presented at the Conference on the Role of Simulation in Space Technology, August 17-21, 1964; Roy F. Brissenden, "Initial Operations with Langley's Rendezvous Docking Facility," Langley Working Paper, LWP-21, 1964; Francis B. Smith, "Simulators for Manned Space Research," Paper presented at the 1966 IEEE International convention, March 21-25, 1966.
NASA Astrophysics Data System (ADS)
Irwin, Patrick G. J.; Teanby, Nicholas N.; Davis, Gary R.; Orton, Glenn; Fletcher, Leigh; Tice, Dane; Hurley, Jane
2010-05-01
In 2006, 2007 and 2008 observations of the near-infrared spectrum of Uranus were made with the UIST instrument of the UK Infrared Telescope, covering the period of Uranus' Northern Spring Equinox in 2008. A significant change in the visible appearance of Uranus occurred during this time with the southern polar zone at 45°S fading, while a corresponding zone at 45°N began to form. In addition, the visibility of the equatorial zone and darker mid-latitude belts increased. The observed spectra were fitted (Irwin et al., Icarus 203, 287 - 302, 2009), using the NEMESIS optimal estimation retrieval model to determine the variation in the latitudinal and vertical cloud structure during this time. However, since publication, a new set of methane absorption data has become available (Karkoschka and Tomasko, 2009, Icarus, submitted), which appears to be more reliable at the cold temperatures and high pressures of Uranus' deep atmosphere. We have fitted k-coefficients to these new methane absorption data and we find that although the inter-annual changes reported by Irwin et al. (2009) stand, the new k-data place the main cloud deck at lower pressures (2-3 bars) than derived previously in the H-band of ~ 3-4 bars and ~ 6 bars in the J-band. In addition, we find that using the new methane coefficients it is much easier to fit simultaneously the 1.6, 1.3 and 1.1 μm peaks. During the Uranus observations in 2007, corresponding observations were also made of Neptune's near-infrared spectrum, albeit with substantially poorer spatial resolution. The spectra were nevertheless sufficient to retrieve the gross variation in Neptune's latitudinal-vertical cloud structure and, like previous studies, we find the main cloud deck to exist at similar pressure levels to the main Uranus cloud deck, but with considerably thicker overlying stratospheric haze. The retrieved vertical-latitudinal cloud structure on Uranus and Neptune, observed with identical instrument setups, will be presented and discussed. Observations of both Uranus and Neptune were also made in 2009 with the SpeX instrument (0.8 to 2.4 μm) on the NASA Infrared Telescope Facility and also with the NIFS and NIRI instruments on the Gemini North telescope. The IRTF measurements were made with seeing conditions of approximately 0.5 arcsec, while the Gemini observations were made with Adaptive Optics and thus have considerably better spatial resolution. We intend to use the NIFS observations to study the limb-darkening curves from 1.45 to 1.75 μm, which should provide better constraints in the vertical cloud structure and we intend to use the IRTF measurements to extend our analysis to shorter wavelengths and also provide better radiometric calibration between the different reflectance peaks. These new observations will be presented and compared with the previous UKIRT observations.
U.S. Air Force Radiation in Space experiment for Gemini 6 flight
1965-12-10
S65-58941 (27 Aug. 1965) --- U.S. Air Force Weapons Laboratory D-8 (Radiation in Space) experiment for Gemini-6 spaceflight. Kennedy Space Center alternative photo number is 104-KSC-65C-5533. Photo credit: NASA
Gemini-Titan (GT)-4 Foods - Documentary Use
1965-01-07
S65-10971 (March 1965 ) --- Food packets for use on the Gemini-3 flight including dehydrated beef pot roast, bacon and egg bites, toasted bread cubes, orange juice and a wet wipe. Water is being inserted into the pouch of dehydrated food.
GEMINI-TITAN (GT)-4 - EARTH-SKY - OUTER SPACE
1965-06-03
S65-34776 (3-7 June 1965) --- This photograph shows the Nile Delta, Egypt, the Suez Canal, Israel, Jordan, Syria, Saudi Arabia, and Iraq as seen from the Gemini-Titan 4 (GT-4) spacecraft during its 12th revolution of Earth.
Gemini 11 prime crew during water egress training in Gulf of Mexico
NASA Technical Reports Server (NTRS)
1966-01-01
Gemini 11 prime crew, Astronauts Richard F. Gordon Jr. (left), pilot, and Charles Conrad Jr., command pilot, relax on deck of the NASA Motor Vessel Retriever after suiting up for water egress training in Gulf of Mexico.
Indonesian Islands as seen from Gemini 11 spacecraft
1966-09-14
S66-54692 (14 Sept. 1966) --- Indonesian Islands (partial cloud cover): Sumatra, Java, Bali, Borneo, and Sumbawa, as photographed from the Gemini-11 spacecraft during its 26th revolution of Earth, at an altitude of 570 nautical miles. Photo credit: NASA
Pazos, Gonzalo; Rivadulla, Marcos L; Pérez-García, Xenxo; Gandara, Zoila; Pérez, Manuel
2014-01-01
The Gemini analogs are the last significant contribution to the family of vitamin D derivatives in medicine, for the treatment of cancer. The first Gemini analog was characterized by two symmetric side chains at C-20. Following numerous modifications, the most active analog bears a C-23-triple bond, C-26, 27- hexafluoro substituents on one side chain and a terminal trideuteromethylhydroxy group on the other side chain. This progression was possible due to improvements in the synthetic methods for the preparation of these derivatives, which allowed for increasing molecular complexity and complete diastereoselective control at C-20 and the substituted sidechains.
1966-05-01
S66-33162 (May 1966) --- Test subject Fred Spross, Crew Systems Division, wears configured extravehicular spacesuit assembly and Extravehicular Life Support System chest pack. The spacesuit legs are covered with Chromel R, which is a cloth woven from stainless steel fibers, used to protect the suit and astronaut from the hot exhaust thrust of the Astronaut Maneuvering Unit backpack. The Gemini spacesuit, backpack and chest pack comprise the AMU, a system which is essentially a miniature manned spacecraft. Astronaut Eugene A. Cernan will wear the AMU during his Gemini-9A extravehicular activity (EVA). Photo credit: NASA
NASA Astrophysics Data System (ADS)
Pope, Crystal L.; Crenshaw, D. Michael; Fischer, Travis C.
2016-01-01
We present a preliminary analysis of the inflows and outflows in the narrow-line regions of nearby (z<0.1) AGN using observations from the Gemini-North telescope's Near-Infared Integral Field Spectrograph (NIFS). In addition to the standard reduction procedure for NIFS data cubes, these observations were treated for multiple sources of noise and artifacts from the adaptive optics observations and the NIFS instrument. This procedure included the following steps: correction of the differential atmospheric refraction, spatial resampling, low-pass Butterworth spatial filtering, removal of the "instrumental fingerprint", and the Richardson-Lucy deconvolution. We compare measurements from NIFS data cubes with and without the additional correction procedures to determine the effect of this data treatment on our scientific results.
Astronaut Frank Borman hoisted from water by recovery helicopter
NASA Technical Reports Server (NTRS)
1966-01-01
Astronaut Frank Borman, command pilot of the Gemini 7 space flight, is hoisted from the water by a recovery helicopter from the Aircraft Carrier U.S.S. Wasp. Below him, Navy divers sit in the life raft next to the Gemini spacecraft.
Gemini-Titan 3 spacecraft in water after flight
NASA Technical Reports Server (NTRS)
1965-01-01
The Gemini-Titan 3 spacecraft is shown in the water after the March 23rd four hour and 53 minute flight. Two helicopters from the recovery ship, the U.S.S. Intrepid, hover over the scene for the pickup of the astronauts.
GEMINI-TITAN (GT)-12 - EARTH SKY - AGENA RENDEZVOUS - OUTER SPACE
1966-11-11
S66-62755 (11 Nov. 1966) --- Excellent stereo and side view of the Agena Target Docking Vehicle as seen from the Gemini-12 spacecraft during rendezvous and docking mission in space. The two spacecraft are 50 feet apart. Photo credit: NASA
GEMINI-6 - EARTH-SKY - ETHIOPIA - OUTER SPACE
1965-12-16
S65-63162 (16 Dec. 1965) --- Central area of Ethiopia, south of Addis Ababa, showing Lakes Zwai, Langana, and Shala, as seen from the Gemini-6 spacecraft during its 14th revolution of Earth. Photo credit: NASA or National Aeronautics and Space Administration
GEMINI-TITAN (GT)-10 - EARTH - SKY
1966-07-01
S66-46054 (18 July 1966) --- Venezuela, British Guyana, Surinam and Trinidad, as seen from the Gemini-10 spacecraft. On the left is the mouth of the Orinoco River in Venezuela. Mouth of Essequibo River in British Guyana is in right center. Photo credit: NASA
Astronaut Gordon Cooper receives preflight medical exam for Gemini 5 flight
1965-08-17
S65-28710 (17 Aug. 1965) --- Astronaut L. Gordon Cooper Jr., command pilot for the Gemini-5 spaceflight, has his blood pressure checked by Dr. Charles A. Berry, chief, Center Medical Programs, Manned Spacecraft Center, during a preflight physical examination.
Astronaut Thomas Stafford during water egress training in Gulf of Mexico
NASA Technical Reports Server (NTRS)
1965-01-01
Astronaut Thomas P. Stafford, Gemini 6 prime crew pilot, climbs out of a boilerplate model of a Gemini spacecraft during water egress training in the Gulf of Mexico. A NASA swimmer in the water nearby assists in the exercise.
GEMINI-TITAN (GT)-9 TEST - ASTRONAUT EUGENE A. WHITE -- PERSONAL - CAPE
1964-06-03
S66-34051 (3 June 1966) --- Astronauts Thomas P. Stafford and Eugene A. Cernan arrive in the White Room atop Pad 19 at the Kennedy Space Center in preparation for the launch of the Gemini-9 spaceflight. Photo credit: NASA
GEMINI SPACECRAFT - ARTIST CONCEPT
1964-01-01
S64-22331 (1964) --- Artist concept illustrating the relative sizes of the one-man Mercury spacecraft, the two-man Gemini spacecraft, and the three-man Apollo spacecraft. Also shows line drawing of launch vehicles to show their relative size in relation to each other. Photo credit: NASA
GEMINI-TITAN (GT)-11 - PREFLIGHT PREP - CHECKOUT - CAPE
1966-07-21
S66-47635 (21 July 1966) --- McDonnell Aircraft Corporation personnel bolt the Gemini-11 spacecraft to a support ring for bore sighting in the Pyrotechnic Installation Building, Merritt Island, during checkout and preflight preparations at the Kennedy Space Center. Photo credit: NASA
Discovery of a wide planetary-mass companion to the young M3 star GU PSC
DOE Office of Scientific and Technical Information (OSTI.GOV)
Naud, Marie-Eve; Artigau, Étienne; Malo, Lison
2014-05-20
We present the discovery of a comoving planetary-mass companion ∼42'' (∼2000 AU) from a young M3 star, GU Psc, a likely member of the young AB Doradus Moving Group (ABDMG). The companion was first identified via its distinctively red i – z color (>3.5) through a survey made with Gemini-S/GMOS. Follow-up Canada-France-Hawaii Telescope/WIRCam near-infrared (NIR) imaging, Gemini-N/GNIRS NIR spectroscopy and Wide-field Infrared Survey Explorer photometry indicate a spectral type of T3.5 ± 1 and reveal signs of low gravity which we attribute to youth. Keck/Adaptive Optics NIR observations did not resolve the companion as a binary. A comparison with atmospheremore » models indicates T {sub eff} = 1000-1100 K and log g = 4.5-5.0. Based on evolution models, this temperature corresponds to a mass of 9-13 M {sub Jup} for the age of ABDMG (70-130 Myr). The relatively well-constrained age of this companion and its very large angular separation to its host star will allow its thorough characterization and will make it a valuable comparison for planetary-mass companions that will be uncovered by forthcoming planet-finder instruments such as Gemini Planet Imager and SPHERE 9.« less
Bergström, L Magnus; Tehrani-Bagha, Alireza; Nagy, Gergely
2015-04-28
Micelles formed by novel gemini esterquat surfactants have been investigated with small-angle neutron scattering (SANS). The growth behavior of the micelles is found to differ conspicuously depending on the length of the gemini surfactant spacer group. The gemini surfactant with a long spacer form rather small triaxial ellipsoidal tablet-shaped micelles that grow weakly with surfactant concentration in the entire range of measured concentrations. Geminis with a short spacer, on the other hand, form weakly growing oblates or tablets at low concentrations that start to grow much more strongly into polydisperse rodlike or wormlike micelles at higher concentrations. The latter behavior is consistent with the presence of a second CMC that marks the transition from the weakly to the strongly growing regime. It is found that the growth behavior in terms of aggregation number as a function of surfactant concentration always appear concave in weakly growing regimes, while switching to convex behavior in strongly growing regimes. As a result, we are able to determine the second CMC of the geminis with short spacer by means of suggesting a rather precise definition of it, located at the point of inflection of the growth curve that corresponds to the transition from concave to convex growth behavior. Our SANS results are rationalized by comparison with the recently developed general micelle model. In particular, this theory is able to explain and reproduce the characteristic appearances of the experimental growth curves, including the presence of a second CMC and the convex strongly growing regime beyond. By means of optimizing the agreement between predictions from the general micelle model and results from SANS experiments, we are able to determine the three bending elasticity constants spontaneous curvature, bending rigidity, and saddle-splay constant for each surfactant.
2009-07-16
A plaque presented to Harvey Allen in recognition of his outstanding solution of the reentry heating problem which has been indispensable to the design of the Mercury, Gemini, and Apollo spacecraft (Manned Spacecraft Center, November 14, 1968) Plaque contains samples of tested materials and models of spacecraft.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hollinger, Geoffrey
This document presents results from tests to demonstrate underwater mapping capabilities of an underwater vehicle in conditions typically found in marine renewable energy arrays. These tests were performed with a tethered Seabotix vLBV300 underwater vehicle. The vehicle is equipped with an inertial navigation system (INS) based on a Gladiator Landmark 40 IMU and Teledyne Explorer Doppler Velocity Log, as well as a Gemini 720i scanning sonar acquired from Tritech. The results presented include both indoor pool and offshore deployments. The indoor pool deployments were performed on October 7, 2016 and February 3, 2017 in Corvallis, OR. The offshore deployment wasmore » performed on April 20, 2016 off the coast of Newport, OR (44.678 degrees N, 124.109 degrees W). During the mission period, the sea state varied between 3 and 4, with an average significant wave height of 1.6 m. Data was recorded from both the INS and the sonar.« less
Young family together after the Gemini 3 mission
NASA Technical Reports Server (NTRS)
1965-01-01
Gemini-Titan 3 Astronaut John W. Young is shown with his wife and children after his return to Cape Kennedy, March 25, from the recovery ship, U.S.S. Intrepid. Shown (left to right) are Young's daughter, Sandra; his son, John; and his wife Barbara.
GEMINI-TITAN (GT)-3 - RECOVERY (HELICOPTER) - ATLANTIC
1965-03-23
S65-19229 (23 March 1965) --- The Gemini-Titan 3 spacecraft is shown in the water after the March 23rd four-hour and 53-minute flight. Two helicopters from the recovery ship, the USS Intrepid, hover over the scene for the pickup of the astronauts.
Egypt, Nile Valley, Gulf of Suez, Sinai as seen from Gemini 12 spacecraft
1966-11-13
S66-63477 (13 Nov. 1966) --- United Arab Republic (Egypt), the Nile Valley from Luxor to Cairo, El Payium, Gulf of Suez, Sinai as seen from Gemini-12 spacecraft on its 25th revolution of Earth. Photo credit: NASA
Geo-Engineering through Internet Informatics (GEMINI)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Doveton, John H.; Watney, W. Lynn
The program, for development and methodologies, was a 3-year interdisciplinary effort to develop an interactive, integrated Internet Website named GEMINI (Geo-Engineering Modeling through Internet Informatics) that would build real-time geo-engineering reservoir models for the Internet using the latest technology in Web applications.
NASA Astrophysics Data System (ADS)
Panda, Manorama; Fatma, Nazish; Kabir-ud-Din
2016-07-01
Three homologues of a novel biodegradable diester-linked cationic gemini surfactant series, CmH2m+1 (CH3)2N+(CH2COOCH2)2N+(CH3)2CmH2m+1.2Cl- (m-E2-m; m = 12, 14, 16), were used for investigation of the solubilization of polycyclic aromatic hydrocarbons (PAHs) such as naphthalene, anthracene and pyrene in single as well as binary surfactant solutions. Physicochemical parameters of the pure/mixed systems were derived by conductivity and surface tension measurements. Dissolution capacity of the equimolar binary surfactant solutions towards the PAHs was studied from the molar solubilization ratio (MSR), micelle-water partition coefficient (Km) and free energy of solubilization (ΔGs0) of the solubilizates. Influence of hydrophobic chain length of the dimeric surfactants on solubilization was characterized. Aqueous solubility of the PAHs was enhanced linearly with concentration of the surfactant in all the pure and mixed gemini-gemini surfactant systems.
Patil, Sachin Vasant; Patil, Sanyukta Arun; Pratap, Amit Prabhakar
2016-09-01
A series of diester containing zwitterionic gemini surfactants, N,N-dimethyl-N-alkyl-2-[[hydroxy (alkoxy) phosphinyl]oxy]-alkylammonium designated as C8(-)-S-Cn(+), S = 2 and 3, n = 12, 14 and 16, were synthesized and characterized by instrumental techniques namely FT-IR, (1)H NMR, (13)C NMR, (31)P NMR and Mass spectral studies. These new gemini surfactants further investigated for their various surfactant properties. The critical micelle concentration (cmc) and the effectiveness of surface tension reduction (Πcmc) were determined as a function of surfactant concentration by means of surface tension measurement. Micellization and viscosity properties were investigated by surface tension, electrical conductivity, dye micellization and rheology techniques. The findings of the aqueous surfactant system obtained were impacted by polarity, size and the nature of zwitterions as the surface. The thermodynamic and viscosity properties of these surfactants found to be based on the structures of gemini surfactants.
Shaban, Samy M; Abd-Elaal, Ali A
2017-07-01
Three novels amide Gemini cationic surfactants with various alkyl chains and their silver nanohybrid with silver nanoparticles were synthesized and a confirmation study for surfactant and their nanoparticles formation has been established using IR, 1 HNMR, TEM and UV-Vis spectroscopy. The surface-active properties of these surfactants and their nanoform were investigated through surface tension and electrical conductivity measurements and a comparative study has been established. The thermodynamic parameters of micellization and adsorption were assessed at temperatures range from 25 to 65°C. The effect of silver particles on the surface behavior of the synthesized surfactant has been discussed. The aggregation behavior of silver nanoparticles with these synthesized Gemini surfactants in water were investigated using dynamic light scattering and transmission electron microscopy. Furthermore, the antimicrobial activities of these synthesized amide Gemini surfactants and their nanostructure with silver against both Gram positive and Gram negative bacteria were also investigated. Copyright © 2017 Elsevier B.V. All rights reserved.
Asp-Gly based peptides confined at the surface of cationic gemini surfactant aggregates.
Brizard, Aurélie; Dolain, Christel; Huc, Ivan; Oda, Reiko
2006-04-11
Cationic gemini surfactants complexed with anionic oligoglycine-aspartate (called gemini peptides hereafter) were synthesized, and their aggregation behaviors were studied. The effects of the hydrophobic chain length (C10-C22) and the length of the oligoglycine (0-4) were investigated, and it was clearly shown by critical micellar concentration, Krafft temperature, and isothermal surface pressure measurements that the hydrophobic effect and interpeptidic interaction influence the aggregation behavior in a cooperative manner. Below their Krafft temperatures, some of them formed both hydro- and organogels with three-dimensional networks and the Fourier transform infrared measurements show the presence of interpeptidic hydrogen bonds.
Multiplying Mars Lander Opportunities with Marsdrop Microlanders
NASA Technical Reports Server (NTRS)
Staehle, Robert L.; Spangelo, Sara; Lane, Marc S.; Aaron, Kim M.; Bhartia, Rohit; Boland, Justin S.; Christensen, Lance E.; Forouhar, Siamak; de la Torre Juarez, Manuel; Trawny, Nikolas;
2015-01-01
From canyons to glaciers, from geology to astrobiology, the amount of exciting surface science awaiting us at Mars greatly outstrips available mission opportunities. Based on the thrice -flown Aerospace Corporation Earth Reentry Breakup Recorder (REBR), we present a method for accurate landing of small instrument payloads on Mars, utilizing excess cruise -stage mass on larger missions. One to a few such microlanders might add 1-5% to the cost of a primary mission with inconsequential risk. Using the REBR and JPL Deep Space 2 starting points for a passively stable entry vehicle provides a low mass and low ballistic coefficient, enabling subsonic d employment of a steerable parawing glider, capable of 10+ km of guided flight at a 3:1 glide ratio. Originally developed for the Gemini human space program, the parawing is attractive for a volume -limited microprobe, minimizing descent velocity, and providing sufficient remaining volume for a useful scientific payload. The ability to steer the parawing during descent opens unique opportunities, including terrain- relative navigation for landing within tens of meters of one of several specified targets within a given uncertainty ellipse. In addition to scientific value, some Mars human exploration Strategic Knowledge Gaps could be addressed with deployment of focused instruments at multiple locations.
Astronauts Grissom and Young prepare to preform flight simulations
1965-03-19
S65-21864 (19 March 1965) --- Astronauts Virgil I. Grissom (left), command pilot; and John W. Young, pilot, prepare to run Gemini-Titan 3 simulations in the Gemini mission simulator at Cape Kennedy, Florida. The NASA GT-3 flight was scheduled for March 23, 1965.
FROGMEN - GEMINI-TITAN (GT)-12 - ATLANTIC
1966-11-15
S66-59987 (15 Nov. 1966) --- A Navy frogman leaps from a recovery helicopter into the water to assist in the Gemini-12 recovery operations. Astronauts James A. Lovell Jr., command pilot, and Edwin E. Aldrin Jr., pilot, had just completed their four-day space mission. Photo credit: NASA
GEMINI-TITAN (GT)-4 - EARTH-SKY - OUTER SPACE
1965-06-01
S65-34670 (3-7 June 1965) --- Richat crater in northwest Africa taken from the Gemini-4 spacecraft. Photograph was taken with a modified 70mm Hasselblad camera, using Eastman color film, ASA 64, at a lens setting of 250th of a second at f/11.
GEMINI-TITAN (GT)-10 - EARTH - SKY - OUTER SPACE
1966-07-01
S66-45951 (18-21 July 1966) --- China, Fukien and Kwangtung provinces, Formosa Strait, Pescadores Island, Quemoy Island, as seen from the Gemini-10 spacecraft. Taken with a J.A. Maurer 70mm camera, using Eastman Kodak, Ektachrome, MS (S.O. 217) color film. Photo credit: NASA
GEMINI-TITAN (GT)-11 - EARTH SKY - OUTER SPACE
1966-09-14
S66-54643 (14 Sept. 1966) --- Western half of Australia, including the coastline from Perth to Port Darwin, looking west, as seen from the Gemini-11 spacecraft at a record-high apogee of 740 nautical miles during its 26th revolution of Earth. Photo credit: NASA
Gemini photographs of the world: A complete index
NASA Technical Reports Server (NTRS)
Giddings, L. E.
1977-01-01
The most authoritative catalogs of photographs of all Gemini missions are assembled. Included for all photographs are JSC (Johnson Space Center) identification number, percent cloud cover, geographical area in sight, and miscellaneous information. In addition, details are given on cameras, filters, films, and other technical details.
ASTRONAUT THOMAS P. STAFFORD - TRAINING (WATER EGRESS) (GT-6 PILOT)
1965-08-23
S65-43954 (23 Aug. 1965) --- Astronaut Thomas P. Stafford, Gemini-6 prime crew pilot, climbs out of a boilerplate model of a Gemini spacecraft during water egress training in the Gulf of Mexico. A NASA swimmer in the water nearby assists in the exercise.
GEMINI-TITAN (GT)-7 - PRELAUNCH ACTIVITY - COMMAND PILOT (LEAVES SUITING TRAILER) - CAPE
1965-12-04
S65-59932 (4 Dec. 1965) --- Prime crew for the Gemini-7 spaceflight astronauts James A. Lovell Jr. (front), pilot, and Frank Borman, command pilot, leave the suiting trailer at Launch Complex 16 during prelaunch countdown at Cape Kennedy, Florida. Photo credit: NASA
Action of Monomeric/Gemini Surfactants on Free Cells and Biofilm of Asaia lannensis.
Koziróg, Anna; Kręgiel, Dorota; Brycki, Bogumił
2017-11-22
We investigated the biological activity of surfactants based on quaternary ammonium compounds: gemini surfactant hexamethylene-1,6-bis-( N,N -dimethyl- N -dodecylammonium bromide) (C6), synthesized by the reaction of N,N -dimethyl- N- dodecylamine with 1,6-dibromohexane, and its monomeric analogue dodecyltrimethylammonium bromide (DTAB). The experiments were performed with bacteria Asaia lannensis , a common spoilage in the beverage industry. The minimal inhibitory concentration (MIC) values were determined using the tube standard two-fold dilution method. The growth and adhesive properties of bacterial cells were studied in different culture media, and the cell viability was evaluated using plate count method. Both of the surfactants were effective against the bacterial strain, but the MIC of gemini compound was significantly lower. Both C6 and DTAB exhibited anti-adhesive abilities. Treatment with surfactants at or below MIC value decreased the number of bacterial cells that were able to form biofilm, however, the gemini surfactant was more effective. The used surfactants were also found to be able to eradicate mature biofilms. After 4 h of treatment with C6 surfactant at concentration 10 MIC, the number of bacterial cells was reduced by 91.8%. The results of this study suggest that the antibacterial activity of the gemini compound could make it an effective microbiocide against the spoilage bacteria Asaia sp. in both planktonic and biofilm stages.
NASA Astrophysics Data System (ADS)
Tran, Debby; Konopacky, Quinn; GPIES Team
2018-01-01
The Gemini Planet Imager (GPI), housed on the 8-meter Gemini South telescope in Chile, is an instrument designed to detect Jupiter-like extrasolar planets by direct imaging. It relies on adaptive optics to correct the effects of atmospheric turbulence, along with an advanced coronagraph and calibration system. One of the scientific goals of GPI is to measure the orbital properties of the planets it discovers. Because these orbits have long periods, precise measurements of the relative position between the star and the planet (relative astrometry) are required. In this poster, I will present the astrometric calibration of GPI. We constrain the plate scale and orientation of the camera by observing different binary star systems with both GPI and another well-calibrated instrument, NIRC2, at the Keck telescope in Hawaii. We measure their separations with both instruments and use that information to calibrate the plate scale. By taking these calibration measurements over the course of three years, we have measured the plate scale to 0.05% and shown that it is stable across multiple epochs. One of the calibrators for GPI is Theta1 Orionis B, one of the star systems in the Trapezium Cluster in Orion. Using GPI and Keck measurements taken over the past several years combined with astrometry from the literature spanning two decades, we can place new constraints on the orbital properties of this massive multiple system. We will present the best fit orbital properties for these objects, including updated mass estimates for the components.
The Late-Time Evolution of SN 2002hh
NASA Astrophysics Data System (ADS)
Clayton, G. C.; Welch, D. L.
2005-12-01
We present new spectroscopic and photometric observations of the interesting Type II-P supernova, SN 2002hh, in NGC 6946. Gemini/GMOS-N has been used to acquire visible spectra and also g'r'i' photometry covering 5 epochs between August 2004 and October 2005, following the evolution of the supernova from 650 to 1050 d since its initial explosion. Supernova spectra obtained 3 years after outburst are rare. In addition, data have been obtained at several epochs in the JHK bands using the Steward 90" with the 256x256 imager and with Gemini/NIRI. Dust emission from SN 2002hh has been detected at mid-infrared wavelengths by SST/IRAC and confirmed by higher angular resolution Gemini/Michelle observations (Barlow et al. 2005, ApJ, 627, L113). There is a pre-existing optically thick dust shell having a mass of ˜0.1 Msun, suggesting a massive M supergiant or luminous blue variable precursor. However, the formation of new dust in the ejecta of SN 2002hh has not been ruled out. The IR emission from any such new dust would be swamped by the emission from the existing circumstellar dust. The new data, presented here, are being used to investigate the late-time evolution of SN 2002hh and whether new dust has been formed in its ejecta. In particular, we are looking for changes in the H-alpha emission line profiles and for variations in brightness due to changes in the extinction and emission due to dust. This study is partially supported by the Natural Sciences and Engineering Research Council of Canada (NSERC).
VizieR Online Data Catalog: Full spectroscopic data release of the SPT-GMOS (Bayliss+, 2016)
NASA Astrophysics Data System (ADS)
Bayliss, M. B.; Ruel, J.; Stubbs, C. W.; Allen, S. W.; Applegate, D. E.; Ashby, M. L. N.; Bautz, M.; Benson, B. A.; Bleem, L. E.; Bocquet, S.; Brodwin, M.; Capasso, R.; Carlstrom, J. E.; Chang, C. L.; Chiu, I.; Cho, H.-M.; Clocchiatti, A.; Crawford, T. M.; Crites, A. T.; de Haan, T.; Desai, S.; Dietrich, J. P.; Dobbs, M. A.; Doucouliagos, A. N.; Foley, R. J.; Forman, W. R.; Garmire, G. P.; George, E. M.; Gladders, M. D.; Gonzalez, A. H.; Gupta, N.; Halverson, N. W.; Hlavacek-Larrondo, J.; Hoekstra, H.; Holder, G. P.; Holzapfel, W. L.; Hou, Z.; Hrubes, J. D.; Huang, N.; Jones, C.; Keisler, R.; Knox, L.; Lee, A. T.; Leitch, E. M.; von der Linden, A.; Luong-van, D.; Mantz, A.; Marrone, D. P.; McDonald, M.; McMahon, J. J.; Meyer, S. S.; Mocanu, L. M.; Mohr, J. J.; Murray, S. S.; Padin, S.; Pryke, C.; Rapetti, D.; Reichardt, C. L.; Rest, A.; Ruhl, J. E.; Saliwanchik, B. R.; Saro, A.; Sayre, J. T.; Schaffer, K. K.; Schrabback, T.; Shirokoff, E.; Song, J.; Spieler, H. G.; Stalder, B.; Stanford, S. A.; Staniszewski, Z.; Stark, A. A.; Story, K. T.; Vanderlinde, K.; Vieira, J. D.; Vikhlinin, A.; Williamson, R.; Zenteno, A.
2016-11-01
The data presented in this paper follow the same observational design described by Ruel et al. (2014ApJ...792...45R). The final Gemini-S observing allocation for SPT-GMOS concluded at the end of the 2015B semester. Over the course of the entire survey we observed 121 individual spectroscopic masks targeting 62 SPT-SZ galaxy clusters (see table 1). All final data products from SPT-GMOS are publicly released via the Harvard Dataverse Network (http://dataverse.harvard.edu/dataverse/SPT_Clusters). The galaxy clusters observed in the SPT-GMOS are all drawn from the SPT-SZ survey, completed in 2011 November. The full SPT-SZ survey covered approximately 2500deg2 of the southern sky at 95, 150, and 220GHz with an angular resolution of ~1'. (4 data files).
Hand-Held Self-Maneuvering Unit to be used during EVA on Gemini 4
1965-06-02
Hand-Held Self-Maneuvering Unit to be used during extravehicular activity (EVA) on Gemini 4 flight. It is an integral unit that contains its own high pressure metering valves and nozzles required to produce controlled thrust. A camera is mounted on the front of the unit.
1965-12-02
S65-56315 (2 Dec. 1965) --- Dr. Charles A. Berry (left), chief of the Manned Spacecraft Center (MSC) Medical Programs, and astronauts James A. Lovell Jr. (center), Gemini-7 pilot, and Frank Borman, Gemini-7 command pilot, examine a series of chest x-rays taken during the preflight physical. Photo credit: NASA
1966-10-01
S66-09382 (1 Oct. 1966) --- Gemini-12 Experiment MSC-7 Bremsstrahlung Spectrometer-Spectrometer Analyzer processor installed in cabin. Objective of experiment is to determine the gamma and beta flux and energy spectra induced inside the spacecraft by exterior electrons. Photo credit: NASA
Astronaut David Scott practicing for Gemini 8 EVA
1966-02-01
S66-19284 (1 Feb. 1966) --- Astronaut David R. Scott practicing for Gemini-8 extravehicular activity (EVA) in building 4 of the Manned Spacecraft Center on the air bearing floor. He is wearing the Hand-Held Maneuvering Unit which he will use during the EVA. Photo credit: NASA
GEMINI-TITAN (GT)-11 - EARTH SKY - OUTER SPACE
1966-09-14
S66-54548 (12-15 Sept. 1966) --- This photograph, taken during one of the 44 orbits the Gemini-11 crew made around Earth, shows the Indian Ocean west of Australia looking northwest. The crew consisted of astronauts Charles Conrad Jr. and Richard F. Gordon Jr. Photo credit: NASA
2009-07-16
John W. 'Jack Boyd holds a plaque presented to Harvey Allen in recognition of his outstanding solution of the reentry heating problem which has been indispensable to the design of the Mercury, Gemini, and Apollo spacecraft (Manned Spacecraft Center, November 14, 1968) Plaque contains samples of tested materials and models of spacecraft.
Performance of the Gemini Planet Imager’s adaptive optics system
Poyneer, Lisa A.; Palmer, David W.; Macintosh, Bruce; ...
2016-01-07
The Gemini Planet Imager’s adaptive optics (AO) subsystem was designed specifically to facilitate high-contrast imaging. We give a definitive description of the system’s algorithms and technologies as built. Ultimately, the error budget indicates that for all targets and atmospheric conditions AO bandwidth error is the largest term.
1965-07-21
S65-39907 (21 July 1965) --- Prime crew for the Gemini-Titan 5 (GT-5) spaceflight, astronauts Charles Conrad Jr. (in water) and L. Gordon Cooper Jr. (in raft) practice survival techniques following successful egress from their Gemini Static Article 5 spacecraft in the Gulf of Mexico. Cooper is command pilot and Conrad is pilot for the GT-5 mission.
WILLIAMS, CLIFTON C. ASTRONAUT - MISSION CONTROL CENTER (MCC) - GEMINI-TITAN (GT)-3 - MSC
1965-03-23
S65-18063 (23 March 1965) --- Astronaut Clifton C. Williams is shown at console in the Mission Control Center (MCC) in Houston, Texas during the Gemini-Titan 3 flight. The GT-3 flight was monitored by the MCC in Houston, but was controlled by the MCC at Cape Kennedy.
ASTRONAUT JAMES A. LOVELL, JR. - RECOVERY - GEMINI-TITAN (GT)-12 - ON BOARD CARRIER - ATLANTIC
1966-11-15
S66-59997 (15 Nov. 1966) --- A happy Gemini-12 prime crew arrives aboard the aircraft carrier, USS Wasp. Astronauts James A. Lovell Jr. (left), command pilot, and Edwin E. Aldrin Jr., pilot, had just been picked up from the splashdown area by helicopter. Photo credit: NASA
GEMINI-TITAN (GT-10) - EARTH SKY - SAHARA - MAURITANIA - ALGERIA - MOROCCO - OUTER SPACE
1966-07-18
S66-46062 (18-21 July 1966) --- Area of the Spanish Sahara--Mauritania--Algeria--Morocco, looking north into Hamada Du Dra, as seen from the Gemini-10 spacecraft. Taken with a J.A. Maurer 70mm camera, using Eastman Kodak, Ektachrome, MS (S.O. 217) color film. Photo credit: NASA
Gemini 11 prime crew during water egress training in Gulf of Mexico
NASA Technical Reports Server (NTRS)
1966-01-01
Astronauts Charles Conrad Jr. (left) and Richard F. Gordon Jr. (right), prime crew for Gemini 11 space flight, practice water egress procedures in the Gulf of Mexico. Static Article 5 was used in the training exercise. A Manned Spaceflight Center (MSC) swimmer is in the water assisting in the training.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-03-26
... SMALL BUSINESS ADMINISTRATION [License No. 01/01-0410] Gemini Investors IV, L.P., Notice Seeking Exemption Under Section 312 of the Small Business Investment Act, Conflicts of Interest Notice is hereby..., Financings which Constitute Conflicts of Interest of the Small Business Administration (``SBA'') Rules and...
Gemini 8 prime and backup crews during press conference
1966-02-26
S66-24380 (26 Feb. 1966) --- Gemini-8 prime and backup crews during press conference. Left to right are astronauts David R. Scott, prime crew pilot; Neil A. Armstrong, prime crew command pilot; Charles Conrad Jr., backup crew command pilot; and Richard F. Gordon Jr., backup crew pilot. Photo credit: NASA
ASTRONAUT CERNAN, EUGENE A. - MISC. (WALK AWAY FROM PAD - GEMINI-TITAN (GT)-9 POSTPONED) - CAPE
1966-05-17
S66-34559 (17 May 1966) --- Astronauts Thomas P. Stafford (left), command pilot, and Eugene A. Cernan, pilot, walk away from Pad 19 after the Gemini-9 mission was postponed. Failure of the Agena Target Vehicle to achieve orbit caused the postponement of the mission. Photo credit: NASA
Implementing an Education and Outreach Program for the Gemini Observatory in Chile.
NASA Astrophysics Data System (ADS)
Garcia, M. A.
2006-08-01
Beginning in 2001, the Gemini Observatory began the development of an innovative and aggressive education and outreach program at its Southern Hemisphere site in northern Chile. A principal focus of this effort is centered on local education and outreach to communities surrounding the observatory and its base facility in La Serena Chile. Programs are now established with local schools using two portable StarLab planetaria, an internet-based teacher exchange called StarTeachers and multiple partnerships with local educational institutions. Other elements include a CD-ROM-based virtual tour that allows students, teachers and the public to experience the observatory's sites in Chile and Hawaii. This virtual environment allows interaction using a variety of immersive scenarios such as a simulated observation using real data from Gemini. Pilot projects like "Live from Gemini" are currently being developed which use internet videoconferencing technologies to bring the observatory's facilities into classrooms at universities and remote institutions. Lessons learned from the implementation of these and other programs will be introduced and the challenges of developing educational programming in a developing country will be shared.
On the Shoulders of Titans: A History of Project Gemini
NASA Technical Reports Server (NTRS)
Hacker, B. C.
1977-01-01
Gemini was the intermediate manned space flight program between America's first steps into space with Mercury and the manned lunar expeditions of Apollo. Because of its position between these two other efforts, Gemini is probably less remembered. Still, it more than had its place in man's progress into this new frontier. Gemini accomplishments were manyfold. They included many firsts: first astronaut-controlled maneuvering in space; first rendezvous in space of one spacecraft with another; first docking of one spacecraft with a propulsive stage and use of that stage to transfer man to high altitude; first traverse of man into the earth's radiation belts; first extended manned flights of a week or more in duration; first extended stays of man outside his spacecraft; first controlled reentry and precision landing; and many more. These achievements were significant in ways one cannot truly evaluate even today, but two things stand out: (1) it was the time when America caught up and surpassed the Soviet Union in manned space flight, and (2) these demonstrations of capability were an absolute prerequisite to the phenomenal Apollo accomplishments then yet to come.
NASA Remembers Astronaut John Young, Moonwalker and First Shuttle Commander
2018-01-06
Astronaut John Young, who walked on the Moon during Apollo 16 and commanded the first space shuttle mission, has passed away at the age of 87. After earning an engineering degree from Georgia Tech and flying planes for the Navy, Young began his impressive career at NASA in 1962, when he was selected from among hundreds of young pilots to join NASA's second astronaut class, known as the "New Nine." Young first flew in space on the first manned Gemini flight, Gemini 3 in March 1965. He later commanded the Gemini 10 mission in July 1966, served as command module pilot on Apollo 10 in 1969, and landed on the Moon as commander of Apollo 16 in April 1972. He went on to command the first Space Shuttle flight in 1981, and also commanded the STS-9 shuttle mission in 1983. He is the only person to go into space as part of the Gemini, Apollo and space shuttle programs and was the first to fly into space six times -- or seven times, when counting his liftoff from the Moon during Apollo 16.
NASA Astrophysics Data System (ADS)
Leggett, S. K.; Saumon, D.; Marley, M. S.; Lodders, K.; Canty, J.; Lucas, P.; Smart, R. L.; Tinney, C. G.; Homeier, D.; Allard, F.; Burningham, Ben; Day-Jones, A.; Fegley, B.; Ishii, Miki; Jones, H. R. A.; Marocco, F.; Pinfield, D. J.; Tamura, M.
2012-04-01
We present i and z photometry for 25 T dwarfs and 1 L dwarf. Combined with published photometry, the data show that the i - z, z - Y, and z - J colors of T dwarfs are very red, and continue to increase through to the late-type T dwarfs, with a hint of a saturation for the latest types with T eff ≈ 600 K. We present new 0.7-1.0 μm and 2.8-4.2 μm spectra for the very late type T dwarf UGPS J072227.51-054031.2, as well as improved astrometry for this dwarf. Examination of the spectral energy distribution using new and published data, with Saumon & Marley models, shows that the dwarf has T eff = 505 ± 10 K, a mass of 3-11 M Jupiter, and an age between 60 Myr and 1 Gyr. This young age is consistent with the thin disk kinematics of the dwarf. The mass range overlaps with that usually considered to be planetary, despite this being an unbound object discovered in the field near the Sun. This apparently young rapid rotator is also undergoing vigorous atmospheric mixing, as determined by the IRAC and WISE 4.5 μm photometry and the Saumon & Marley models. The optical spectrum for this 500 K object shows clearly detected lines of the neutral alkalis Cs and Rb, which are emitted from deep atmospheric layers with temperatures of 900-1200 K. Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the Science and Technology Facilities Council (United Kingdom), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), Ministério da Ciência e Tecnologia (Brazil), and Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina); also based on data collected at Subaru Telescope, which is operated by the National Astronomical Observatory of Japan; and also based on observations made at the UK Infrared Telescope, which operated by the Joint Astronomy Centre on behalf of the Science and Technology Facilities Council of the UK.
Experiment M-6: Bone Demineralization
NASA Technical Reports Server (NTRS)
Mack, Pauline B.; Vose, George; Vogt, Fred B.; LaChance, Paul A.
1966-01-01
Densitometric evaluations of serial radiographs of "normal" subjects have often shown rather frequent changes in bone mass within relatively short periods of time. For this reason it was decided to make two pre-flight and two post flight radiographs of the Gemini V backup crew. In comparing the changes observed preflight and post flight as the conventional os calcis scanning site between the two crews, it was found that no changes greater than 4 percent were evident in either member of the backup crew. In comparing the changes observed preflight and postflight as the conventional o calcis scanning site between the two crews, it was found that no changes greater than 4 percent were evident in either member of the backup crew. This is in contract to the 15.1 and 8.9 percent losses observed in the prime crew. It has long been known that the skeletal system experiences a general loss of mineral under immobilization or extended bed rest. However, in both Gemini IV and Gemini V studies, bone mass losses were greater in both the os calcis and phalanx than were shown by the TWU bed-rest subjects during the same period of time. Although the bone mass losses in the 8-day Gemini V flight were generally greater than in the 4-day Gemini IV flight, the information to date is still insufficient to conclude that the losses tend to progress linearly with time, or whether a form of physiological adaptation may occur in longer space flights.
Pietralik, Zuzanna; Kumita, Janet R; Dobson, Christopher M; Kozak, Maciej
2015-07-01
Very important to gene therapy is the delivery system of the nucleic acids (called a vector), which will enhance the efficiency of the transport of new DNA into cells whilst protecting against damage. A promising alternative to the currently used viral vectors are the systems based on amphiphilic compounds - lipoplexes. Among them, gemini surfactants, which consist of two hydrophobic chains and two cationic heads connected by a linker - spacer group, appear to be promising candidates. The subject of this study involves two gemini surfactants, alkoxy derivatives of bis-imidazolium quaternary salts, differing in the length of their spacer groups and how they interact with two types of salmon sperm DNA (low and high molecular weight (MW)) or plasmid DNA (pDNA). The mixtures of gemini surfactants with nucleic acids of differing p/n ratios (positive-to-negative charge ratio) were characterised by small angle X-ray scattering (SAXS) of synchrotron radiation, dynamic light scattering (DLS), circular dichroism (CD) spectroscopy, atomic force microscopy (AFM), transmission electron microscopy (TEM) and gel electrophoresis techniques. This analysis allows for the selection of the most suitable and promising candidates for non-viral vectors in gene therapy, determination of the conditions needed to form stable complexes, identification of conformational changes in the DNA molecules upon interactions with gemini surfactants and in some cases, determination of the structures formed in these lipoplexes. Copyright © 2015 Elsevier B.V. All rights reserved.
Determinations of the 12C/13C Ratio for the Secondary Stars of AE Aquarii, SS Cygni, and RU Pegasi
NASA Astrophysics Data System (ADS)
Harrison, Thomas E.; Marra, Rachel E.
2017-07-01
We present new moderate-resolution near-infrared spectroscopy of three CVs obtained using GNIRS on Gemini-North. These spectra covered three 13CO bandheads found in the K-band, allowing us to derive the isotopic abundance ratios for carbon. We find small 12C/13C ratios for all three donor stars. In addition, these three objects show carbon deficits, with AE Aqr being the most extreme ([C/Fe] = -1.4). This result confirms the conjecture that the donor stars in some long-period CVs have undergone considerable nuclear evolution prior to becoming semi-contact binaries. In addition to the results for carbon, we find that the abundance of sodium is enhanced in these three objects, and the secondary stars in both RU Peg and SS Cyg suffer magnesium deficits. Explaining such anomalies appears to require higher mass progenitors than commonly assumed for the donor stars of CVs. Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the National Research Council (Canada), CONICYT (Chile), Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina), and Ministério da Ciência, Tecnologia e Inovação (Brazil).
Adak, Sunita; Datta, Sougata; Bhattacharya, Santanu; Banerjee, Rintu
2015-11-01
An insight into the effects of new ionic liquid-type gemini imidazolium cationic surfactants on the structure and function of the lipases is of prime importance for their potential application. Changes in the activity, stability and structure of Rhizopus oryzae lipase in the presence of novel gemini surfactants, [C16-3-C16im]Br2 and [C16-12-C16im]Br2 were probed in the present study. Surfactant with shorter spacer length, [C16-3-C16im]Br2 was found to be better in improving the hydrolytic activity and thermal stability of the lipase. For both the surfactants, activation was concentration dependent. CD spectroscopy results showed a decrease in α-helix and an increase in β-sheet content in the presence of these surfactants. A higher structural change observed in presence of [C16-12-C16im]Br2 correlated with lower enzyme activity. Isothermal titration calorimetric studies showed the binding to be spontaneous in nature based on sequential two site binding model. The forces involved in binding were found to differ for the two surfactants proving that the spacer length is an important factor which governs the interaction. These surfactants could be used as promising components both in enzyme modification and media engineering for attaining the desired goals in biocatalytic reactions. Copyright © 2015 Elsevier B.V. All rights reserved.
A Dark Spot on a Massive White Dwarf
NASA Astrophysics Data System (ADS)
Kilic, Mukremin; Gianninas, Alexandros; Bell, Keaton J.; Curd, Brandon; Brown, Warren R.; Hermes, J. J.; Dufour, Patrick; Wisniewski, John P.; Winget, D. E.; Winget, K. I.
2015-12-01
We present the serendipitous discovery of eclipse-like events around the massive white dwarf SDSS J152934.98+292801.9 (hereafter J1529+2928). We selected J1529+2928 for time-series photometry based on its spectroscopic temperature and surface gravity, which place it near the ZZ Ceti instability strip. Instead of pulsations, we detect photometric dips from this white dwarf every 38 minutes. Follow-up optical spectroscopy observations with Gemini reveal no significant radial velocity variations, ruling out stellar and brown dwarf companions. A disintegrating planet around this white dwarf cannot explain the observed light curves in different filters. Given the short period, the source of the photometric dips must be a dark spot that comes into view every 38 minutes due to the rotation of the white dwarf. Our optical spectroscopy does not show any evidence of Zeeman splitting of the Balmer lines, limiting the magnetic field strength to B < 70 kG. Since up to 15% of white dwarfs display kG magnetic fields, such eclipse-like events should be common around white dwarfs. We discuss the potential implications of this discovery on transient surveys targeting white dwarfs, like the K2 mission and the Large Synoptic Survey Telescope. This work is based on observations obtained at the Gemini Observatory, McDonald Observatory, and the Apache Point Observatory 3.5-m telescope. The latter is owned and operated by the Astrophysical Research Consortium. Gemini Observatory is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), Ministério da Ciência, Tecnologia e Inovação (Brazil) and Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina).
The Black Hole Safari: Big Game Hunting in 30+ Massive Galaxies
NASA Astrophysics Data System (ADS)
McConnell, Nicholas J.; Ma, Chung-Pei; Janish, Ryan; Gebhardt, Karl; Lauer, Tod R.; Graham, James R.
2015-01-01
The current census of the most massive black holes in the local universe turns up an odd variety of galaxy hosts: central galaxies in rich clusters, second- or lower-ranked cluster members, and compact relics from the early universe. More extensive campaigns are required to explore the number density and environmental distribution of these monsters. Over the past three years we have collected a large set of stellar kinematic data with sufficient resolution to detect the gravitational signatures of supermassive black holes with MBH > 109 MSun. This Black Hole Safari targets enormous galaxies at the centers of nearby galaxy clusters, as well as their similarly luminous counterparts in weaker galaxy groups. To date we have observed more than 30 early-type galaxies with integral-field spectrographs on the Keck, Gemini North, and Gemini South telescopes. Here I present preliminary stellar kinematics from 10 objects.
Technicians prepare to close hatches on Gemini 11 spacecraft during countdown
NASA Technical Reports Server (NTRS)
1966-01-01
Technicians in the White Room atop Pad 19 prepare to close hatches on the Gemini 11 spacecraft during prelaunch countdown. Inside the spacecraft are Astronauts Charles Conrad Jr., command pilot, and Richard F. Gordon Jr., pilot. There is a humorous sign stating 'This is ABSOLUTELY your Last Chance' being held by one of the technicians.
MAGNETOMETER - TRI-AXIS SENSOR UNIT - GEMINI-TITAN (GT)-12 EXPERIMENT MSC-3 (M405) - MSC
1966-10-01
S66-09379 (1 Oct. 1966) --- Tri-Axis Magnetometer-Sensor Unit mounted on telescoping boom. Cable connects Sensor Unit with Electronics Unit mounted on retrograde beam in retrograde adapter section. Objective of experiment is to monitor the direction and amplitude of Earth's magnetic field (Gemini-12). Photo credit: NASA
ERIC Educational Resources Information Center
Anzovino, Mary E.; Greenberg, Andrew E.; Moore, John W.
2015-01-01
A laboratory experiment is described in which students synthesize a variety of cationic gemini surfactants and analyze their efficacy as fabric softeners. Students perform a simple organic synthesis reaction and two analytical tests (one qualitative and one quantitative), and use the class data to assess the synthesized products. The experiment…
Federal Register 2010, 2011, 2012, 2013, 2014
2013-07-05
... SECURITIES AND EXCHANGE COMMISSION [File No. 500-1] GDT Tek, Inc., Gemini Explorations, Inc., Genetic Vectors, Inc., and Global Gate Property Corp.; Order of Suspension of Trading July 2, 2013. It... Genetic Vectors, Inc. because it has not filed any periodic reports since the period ended September 30...
Gemini 6 crew during press conference
1965-04-06
S65-19406 (6 April 1965) --- Astronauts Thomas P. Stafford (left), pilot; and Walter M. Schirra Jr., command pilot, have been named as the prime crew for the Gemini-Titan 6 spaceflight. Schirra and Stafford served as the GT-3 backup crew. Their selection for the GT-6 flight was announced at an MSC news conference on April 6, 1965.
Central portion of Florida, Gulf of Mexico seen from Gemini 11
1966-09-14
S66-54565 (14 Sept. 1966) --- Central portion of Florida, Gulf of Mexico to Atlantic Ocean, Cape Kennedy is at left center of photo, as seen from the Gemini-11 spacecraft during its 29th revolution of Earth. Photo lacks detail due to low sun angle. Sunglint on lakes is visible. Photo credit: NASA
MISSION CONTROL CENTER (MCC) - GEMINI-TITAN (GT)-6 - SCRUBBED - MSC
1965-10-25
S65-44401 (1965) --- A group of National Aeronautics and Space Administration (NASA) and Manned Spacecraft Center (MSC) officials and personnel watch a Cape Kennedy press conference being telecast in the Mission Control Center (MCC) after the Gemini-6 mission was scrubbed due to the apparent failure of the Agena Target Vehicle to attain orbit.
GEMINI-TITAN-8 - TRAINING - WATER EGRESS
1966-01-15
S66-17253 (15 Jan. 1966) --- Astronauts Neil A. Armstrong (center), command pilot, and David R. Scott (right), pilot of the Gemini-8 prime crew, are suited up for water egress training aboard the NASA Motor Vessel Retriever in the Gulf of Mexico. At left is Dr. Kenneth N. Beers, M.D., Flight Medicine Branch, Center Medical Office. Photo credit: NASA
ASTRONAUT THOMAS P. STAFFORD - TRAINING (WATER EGRESS) (GEMINI-TITAN [GT]-6 PILOT)(HEAD SHOT) - GULF
1965-08-23
S65-43971 (23 Aug. 1965) --- Astronaut Thomas P. Stafford, Gemini-6 prime crew pilot, is pictured onboard the NASA Motor Vessel Retriever in the Gulf of Mexico during water egress training. Astronaut Walter M. Schirra Jr. (out of frame), prime crew command pilot, also took part in the training.
Agena Target Vehicle atop Atlas Launch vehicle launched from KSC
NASA Technical Reports Server (NTRS)
1966-01-01
An Agena Target Vehicle atop its Atlas Launch vehicle is launched from the Kennedy Space Center (KSC) Launch Complex 14 at 10:15 am.m., May 17, 1966. The Agena was intended as a rendezvous and docking vehicle for the Gemini 9 spacecraft. However, since the Agena failed to achieve orbit, the Gemini 9 mission was postponed.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Turri, P.; McConnachie, A. W.; Stetson, P. B.
2015-10-01
The Extremely Large Telescopes currently under construction have a collecting area that is an order of magnitude larger than the present largest optical telescopes. For seeing-limited observations the performance will scale as the collecting area, but with the successful use of adaptive optics (AO), for many applications it will scale as D{sup 4} (where D is the diameter of the primary mirror). Central to the success of the ELTs, therefore, is the successful use of multi-conjugate adaptive optics (MCAO) which applies a high degree of correction over a field of view larger than the few arcseconds that limits classical AOmore » systems. In this Letter, we report on the analysis of crowded field images taken on the central region of the galactic globular cluster NGC 1851 in the K{sub s} band using the Gemini Multi-conjugate Adaptive Optics System (GeMS) at the Gemini South Telescope, the only science-grade MCAO system in operation. We use this cluster as a benchmark to verify the ability to achieve precise near-infrared photometry by presenting the deepest K{sub s} photometry in crowded fields ever obtained from the ground. We construct a color–magnitude diagram in combination with the F606W band from the Hubble Space Telescope/Advanced Camera for Surveys. As well as detecting the “knee” in the lower main sequence at K{sub s} ≃ 20.5, we also detect the double subgiant branch of NGC 1851, which demonstrates the high photometric accuracy of GeMS in crowded fields.« less
Near-Infrared photometry of BOs and Centaurs in support of Spitzer Space Telescope data
NASA Astrophysics Data System (ADS)
Pinilla-Alonso, Noemi; Emery, Josh P.; Trilling, David; Mommert, Michael
2014-08-01
We propose to measure near-infrared broadband colors of Centaurs and Kuiper Belt objects (KBOs). The proposed ground-based observations will complement 3.6 and 4.5 microns photometry of these bodies obtained with the Infrared Array Camera (IRAC) on the Spitzer Space Telescope. Extending reflectances past 2.5 micron with Spitzer enables sensitive searches for absorptions in the 3 to 5 micron region, where relevant species (e.g., complex organics, H2O, CO2, CH4, hydrated silicates) have their fundamental absorption bands. In order to assess the presence of absorptions, however, the Spitzer photometry must be tied to shorter wavelength near-infrared reflectances. Recently, Wright et al. (2012) combined IRAC/Spitzer and NIR colors for a sample of cold KBOs and showed how powerful this technique is detecting the presence of volatiles. In semester 2011B we obtained Gemini NIR data for 12 KBOs (results were presented in the DPS Meeting 2012 and part is included in the Master Dissertation of D. Wright, under the supervision of J.P. Emery). In semester 2011B and 2013A we obtained Gemini NIR data for 12 and 7 KBOs respectively (part of these results were presented in the DPS Meeting 2012 and part is included in the Master Dissertation of D. Wright, under the supervision of J.P. Emery). But our sample is not yet completed and we need more time to complete our study and cover a larger number of targets from our sample of Spitzer data. Approximately 54 objects in our sample that lack NIR colors are visible from GEMINI South in 2014B semester, we propose here to observe 16 of these objects.
The complex jet- and bar-perturbed kinematics in NGC 3393 as revealed with ALMA and GEMINI-GMOS/IFU
NASA Astrophysics Data System (ADS)
Finlez, Carolina; Nagar, Neil M.; Storchi-Bergmann, Thaisa; Schnorr-Müller, Allan; Riffel, Rogemar A.; Lena, Davide; Mundell, C. G.; Elvis, Martin S.
2018-06-01
NGC 3393, a nearby Seyfert 2 galaxy with nuclear radio jets, large-scale and nuclear bars, and a posited secondary super massive black hole, provides an interesting laboratory to test the physics of inflows and outflows. Here we present and analyse the molecular gas (ALMA observations of CO J:2-1 emission over a field of view (FOV) of 45" × 45", at 0."56 (143 pc) spatial and 5 km/s spectral resolution), ionised gas and stars (GEMINI-GMOS/IFU; over a FOV of 4" × 5", at 0."62 (159 pc) spatial and 23 km/s spectral resolution) in NGC 3393. The ionised gas emission, detected over the complete GEMINI-GMOS FOV, has three identifiable kinematic components. A narrow (σ < 115 km/s) component present in the complete FOV, which is consistent with rotation in the galaxy disk. A broad (σ > 115 km/s) redshifted component, detected near the NE and SW radio lobes; which we interpret as a radio jet driven outflow. And a broad (σ > 115 km/s) blueshifted component that shows high velocities in a region perpendicular to the radio jet axis; we interpret this as an equatorial outflow. The CO J:2-1 emission is detected in spiral arms on 5" - 20" scales, and in two disturbed circumnuclear regions. The molecular kinematics in the spiral arms can be explained by rotation. The highly disturbed kinematics of the inner region can be explained by perturbations induced by the nuclear bar and interactions with the large scale bar. We find no evidence for, but cannot strongly rule out, the presence of the posited secondary black hole.
In This Decade, Mission to the Moon.
ERIC Educational Resources Information Center
National Aeronautics and Space Administration, Washington, DC.
The development and accomplishments of the National Aeronautics and Space Administration (NASA) from its inception in 1958 to the final preparations for the Apollo 11 mission in 1969 are traced in this brochure. A brief account of the successes of projects Mercury, Gemini, and Apollo is presented and many color photographs and drawings of the…
Operation and Service Manual for Computer System Test Console 52E270003. Volume I.
portion of the Inertial Guidance System in the Gemini Spacecraft during system and pre-launch testing. The TCCS is manufactured by the International ... Business Machines (IBM) Corporation of Rockville, Maryland for the McDonnell Company of St. Louis, Missouri. The report presents a description of the TCCS
Subaru And Gemini Observations Of SS 433: New Constraint On The Mass Of The Compact Object
NASA Astrophysics Data System (ADS)
Kubota, K.; Ueda, Y.; Fabrika, S.; Medvedev, A.; Barsukova, E. A.; Sholukhova, O.; Goranskij, V. P.
2010-02-01
We present results of optical spectroscopic observations of the mass donor star in SS 433 with Subaru and Gemini, with an aim to best constrain the mass of the compact object. Subaru/Faint Object Camera and Spectrograph observations were performed on four nights of 2007 October 6-8 and 10, covering the orbital phase of phi = 0.96 - 0.26. We first calculate the cross-correlation function (CCF) of these spectra with that of the reference star HD 9233 in the wavelength range of 4740-4840 Å. This region is selected to avoid "strong" absorption lines accompanied with contaminating emission components, which most probably originate from the surroundings of the donor star, such as the wind and gas stream. The same analysis is applied to archive data of Gemini/GMOS taken at phi = 0.84 - 0.30 by Hillwig & Gies. From the Subaru and Gemini CCF results, the amplitude of the radial velocity curve of the donor star is determined to be 58.3 ± 3.8 km s-1 with a systemic velocity of 59.2 ± 2.5 km s-1. Together with the radial velocity curve of the compact object, we derive the mass of the donor star and compact object to be M O = 12.4 ± 1.9 M sun and M X = 4.3 ± 0.6 M sun, respectively. We conclude, however, that these values should be taken as upper limits. From the analysis of the averaged absorption line profiles of strong lines (mostly ions) and weak lines (mostly neutrals) observed with Subaru, we find evidence for heating effects from the compact object. Using a simple model, we find that the true radial velocity amplitude of the donor star could be as low as 40 ± 5 km s-1 in order to produce the observed absorption-line profiles. Taking into account the heating of the donor star may lower the derived masses to M O = 10.4+2.3 -1.9 M sun and M X = 2.5+0.7 -0.6 M sun. Our final constraint, 1.9 M sun <=M X<= 4.9 M sun, indicates that the compact object in SS 433 is most likely a low mass black hole, although the possibility of a massive neutron star cannot be firmly excluded. Based on data collected at Subaru Telescope, which is operated by the National Astronomical Observatory of Japan. Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (USA), the Science and Technology Facilities Council (UK), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), Ministério da Ciência e Tecnologia (Brazil), and SECYT (Argentina).
Singh, Jagbir; Yang, Peng; Michel, Deborah; Verrall, Ronald E; Foldvari, Marianna; Badea, Ildiko
2011-05-01
Gene based therapy represents an important advance in the treatment of diseases that heretofore have had either no treatment or cure. To capitalize on the true potential of gene therapy, there is a need to develop better delivery systems that can protect these therapeutic biomolecules and deliver them safely to the target sites. Recently, we have designed and developed a series of novel amino acid-substituted gemini surfactants with the general chemical formula C(12)H(25) (CH(3))(2)N(+)-(CH(2))(3)-N(AA)-(CH(2))(3)-N(+) (CH(3))(2)-C(12)H(25) (AA= glycine, lysine, glycyl-lysine and, lysyl-lysine). These compounds were synthesized and tested in rabbit epithelial cells using a model plasmid and a helper lipid. Plasmid/gemini/lipid (P/G/L) nanoparticles formulated using these novel compounds achieved higher gene expression than the nanoparticles containing the parent unsubstituted compound. In this study, we evaluated the cytotoxicity of P/G/L nanoparticles and explored the relationship between transfection efficiency/toxicity and their physicochemical characteristics (such as size, binding properties, etc.). An overall low toxicity is observed for all complexes with no significant difference among substituted and unsubstituted compounds. An interesting result revealed by the dye exclusion assay suggests a more balanced protection of the DNA by the glycine and glycyl-lysine substituted compounds. Thus, the higher transfection efficiency is attributed to the greater biocompatibility and flexibility of the amino acid/peptide-substituted gemini surfactants and demonstrates the feasibility of using amino acid-substituted gemini surfactants as gene carriers for the treatment of diseases affecting epithelial tissue.
2004-04-15
The Titan II liftoff. The Titan II launch vehicle was used for carrying astronauts on the Gemini mission. The Gemini Program was an intermediate step between the Project Mercury and the Apollo Program. The major objectives were to subject are two men and supporting equipment to long duration flights, to effect rendezvous and docking with other orbiting vehicle, and to perfect methods of reentry, and landing the spacecraft.
1966-08-15
S66-51073 (15 Aug. 1966) --- Astronaut Edwin E. Aldrin Jr., prime crew pilot of the Gemini-12 spaceflight, undergoes evaluation procedures with the Astronaut Maneuvering Unit in the 30-foot altitude chamber at McDonnell. The suited Aldrin is wearing an AMU backpack and an Extravehicular Life Support System (ELSS) chest pack. Photo credit: NASA
Astronaut L. Gordon Cooper Jr. - Misc. - Gemini-Titan (GT)-5 - Suiting-Up - Prime Crew - Cape
1965-08-19
S65-46367 (19 Aug. 1965) --- Astronauts Charles Conrad Jr. (right) and L. Gordon Cooper Jr. are pictured during suiting up operations before Gemini-5 spaceflight. Editor's note: The scheduled Aug. 19 launch was postponed due to weather conditions and problems with loading cryogenic fuel for the fuel cell. The launch occurred on Aug. 21, 1965.
Gemini 4 prime crew with Official medical nurse for Astronaut crew members
NASA Technical Reports Server (NTRS)
1965-01-01
Gemini 4 prime crew, Astronauts Edward H. White II, (left), and James A. McDivitt (right) are shown with Lt. Dolores (Dee) O'Hare, US Air Force, Center Medical Office, Flight Medicine Branch, Manned Spaceflight Center (MSC). Lieutenant O'Hare has served during several space flights as Official medical nurse for the astronaut crew members on the missions.
Gemini 9 crew in spacecraft with technicians closing hatches
NASA Technical Reports Server (NTRS)
1966-01-01
Technicians prepare to close the hatches on the Gemini 9-A spacecraft in the White Room atop Pad 19 after insertion of Astronauts Thomas P. Stafford (left) and Eugene A. Cernan. Liftoff was at 8:39 a.m., June 3, 1966. Humorous sign from backup crew, James A. Lovell Jr. and Edwin E. Aldrin Jr., was taped to the spacecraft.
View of food packets for the Gemini 7 space flight
1965-12-10
S65-61653 (1 Dec. 1965) --- Complete food supply for the two-man crew of the National Aeronautics and Space Administration's Gemini-7 spaceflight as it appears prior to stowage in the spacecraft. The food packages are tied in sequence for 28-manned days or a complete supply for two men for a 14-day mission. Photo credit: NASA
Gemini 9-A astronauts talk to reporters at Ellington field at end of mission
NASA Technical Reports Server (NTRS)
1966-01-01
The Gemini 9-A prime crew, Astronauts Thomas Stafford (left), command pilot, and Eugene Cernan (right), pilot, express their feelings about being home to their families, Manned Spacecraft Center (MSC) Officials, newsmen and well-wishers gathered at Ellington Air Force Base to welcome the astronauts home. At right is George M. Low, MSC Deputy Director.
Three MSC officials hold discussion in Mission Control room during Gemini 11
1966-09-12
S66-52754 (12 Sept. 1966) --- Three key Manned Spacecraft Center (MSC) officials hold discussion in the Mission Control room during Gemini-11 activity. Left to right, are Donald K. Slayton, MSC Director of Flight Crew Operations; astronaut Alan B. Shepard Jr., Chief, MSC Astronaut Office; and George M. Low, MSC Deputy Director. Photo credit: NASA
GORDON, RICHARD F., ASTRONAUT - TRAINING - GEMINI-TITAN (GT)-11 - WATER EGRESS - GULF
1966-07-23
S66-44497 (23 July 1966) --- Astronauts Charles Conrad Jr. (left) and Richard F. Gordon Jr. (right), prime crew for the Gemini-11 spaceflight, practice water egress procedures in the Gulf of Mexico. Static Article 5 was used in the training exercise. A MSC swimmer is in the water assisting in the training. Photo credit: NASA
ERIC Educational Resources Information Center
Smith, Lee; van Jaarsveld, Cornelia H. M.; Llewellyn, Clare H.; Fildes, Alison; López Sánchez, Guillermo Felipe; Wardle, Jane; Fisher, Abigail
2017-01-01
Purpose: Variability in the timing of infant developmental milestones is poorly understood. We used a twin analysis to estimate genetic and environmental influences on motor development and activity levels in infancy. Method: Data were from the Gemini Study, a twin birth cohort of 2,402 families with twins born in the United Kingdom in 2007.…
16 febbraio 2004. 121 Hermione occulta la stella TYC 1905-00864-1 in Gemini
NASA Astrophysics Data System (ADS)
Corbisiero, Massimo
2005-04-01
On 16 February 2004, the asteroid 121 Hermione occulted the star TYC 1905-00864-1 in Gemini: new astrometric observations and duplicity of the asteroid lead the UAI Occultation Section to launch a call for observations throughout Italy. Interesting results have been obtained along with new dimensions of the asteroid derived from positive observations.
Hyperactivity and Dust Composition of Comet 103P/Hartley 2 During the EPOXI Encounter
NASA Astrophysics Data System (ADS)
Harker, David E.; Woodward, Charles E.; Kelley, Michael S. P.; Wooden, Diane H.
2018-05-01
Short-period comet 103P/Hartley 2 (103P) was the flyby target of the Deep Impact eXtended Investigation on 2010 November 4 UT. This comet has a small hyperactive nucleus, i.e., it has a high water production rate for its surface area. The underlying cause of the hyperactivity is unknown; the relative abundances of volatiles in the coma of 103P are not unusual. However, the dust properties of this comet have not been fully explored. We present four epochs of mid-infrared spectra and images of comet 103P observed from Gemini-South +T-ReCS on 2010 November 5, 7, 21 and December 13 UT, near and after the spacecraft encounter. Comet 103P exhibited a weak 10 μm emission feature ≃1.14 ± 0.01 above the underlying local 10 μm continuum. Thermal dust grain modeling of the spectra shows the grain composition (mineralogy) was dominated by amorphous carbon and amorphous pyroxene with evidence for Mg-rich crystalline olivine. The grain size has a peak grain radius range of a peak ∼ 0.5–0.9 μm. On average, the crystalline silicate mass fraction is ≃0.24, fairly typical of other short-period comets. In contrast, the silicate-to-carbon ratio of ≃0.48–0.64 is lower compared to other short-period comets, which indicates that the flux measured in the 10 μm region of 103P was dominated by amorphous carbon grains. We conclude that the hyperactivity in comet 103P is not revealing dust properties similar to the small grains seen with the Deep Impact experiment on comet 9P/Tempel 1 or from comet C/1995 O1 (Hale–Bopp).
DOE Office of Scientific and Technical Information (OSTI.GOV)
Currie, Thayne; Cloutier, Ryan; Jayawardhana, Ray
2014-11-10
We present new L' (3.8 μm) and Brα (4.05 μm) data and reprocessed archival L' data for the young, planet-hosting star HR 8799 obtained with Keck/NIRC2, VLT/NaCo, and Subaru/IRCS. We detect all four HR 8799 planets in each data set at a moderate to high signal-to-noise ratio (S/N ≳ 6-15). We fail to identify a fifth planet, 'HR 8799 f', at r < 15 AU at a 5σ confidence level: one suggestive, marginally significant residual at 0.''2 is most likely a point-spread function artifact. Assuming companion ages of 30 Myr and the Baraffe planet cooling models, we rule out anmore » HR 8799 f with a mass of 5 M{sub J} (7 M{sub J} ), 7 M{sub J} (10 M{sub J} ), or 12 M{sub J} (13 M{sub J} ) at r {sub proj} ∼ 12 AU, 9 AU, and 5 AU, respectively. All four HR 8799 planets have red early T dwarf-like L' – [4.05] colors, suggesting that their spectral energy distributions peak in between the L' and M' broadband filters. We find no statistically significant difference in HR 8799 cde's color. Atmosphere models assuming thick, patchy clouds appear to better match HR 8799 bcde's photometry than models assuming a uniform cloud layer. While non-equilibrium carbon chemistry is required to explain HR 8799 b and c's photometry/spectra, evidence for it from HR 8799 d and e's photometry is weaker. Future, deep-IR spectroscopy/spectrophotometry with the Gemini Planet Imager, SCExAO/CHARIS, and other facilities may clarify whether the planets are chemically similar or heterogeneous.« less
Post-maximum Near-infrared Spectra of SN 2014J: A Search for Interaction Signatures
NASA Astrophysics Data System (ADS)
Sand, D. J.; Hsiao, E. Y.; Banerjee, D. P. K.; Marion, G. H.; Diamond, T. R.; Joshi, V.; Parrent, J. T.; Phillips, M. M.; Stritzinger, M. D.; Venkataraman, V.
2016-05-01
We present near-infrared (NIR) spectroscopic and photometric observations of the nearby Type Ia SN 2014J. The 17 NIR spectra span epochs from +15.3 to +92.5 days after B-band maximum light, while the {{JHK}}s photometry include epochs from -10 to +71 days. These data are used to constrain the progenitor system of SN 2014J utilizing the Paβ line, following recent suggestions that this phase period and the NIR in particular are excellent for constraining the amount of swept-up hydrogen-rich material associated with a non-degenerate companion star. We find no evidence for Paβ emission lines in our post-maximum spectra, with a rough hydrogen mass limit of ≲ 0.1 M ⊙, which is consistent with previous limits in SN 2014J from late-time optical spectra of the Hα line. Nonetheless, the growing data set of high-quality NIR spectra holds the promise of very useful hydrogen constraints. Based on observations obtained at the Gemini Observatory under program GN-2014A-Q-8 (PI: Sand). Gemini is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the National Research Council (Canada), CONICYT (Chile), Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina), and Ministério da Ciência, Tecnologia e Inovação (Brazil).
Jani, Mehul; Mathee, Kalai; Azad, Rajeev K.
2016-01-01
Pseudomonas aeruginosa is an opportunistic pathogen implicated in a myriad of infections and a leading pathogen responsible for mortality in patients with cystic fibrosis (CF). Horizontal transfers of genes among the microorganisms living within CF patients have led to highly virulent and multi-drug resistant strains such as the Liverpool epidemic strain of P. aeruginosa, namely the LESB58 strain that has the propensity to acquire virulence and antibiotic resistance genes. Often these genes are acquired in large clusters, referred to as “genomic islands (GIs).” To decipher GIs and understand their contributions to the evolution of virulence and antibiotic resistance in P. aeruginosa LESB58, we utilized a recursive segmentation and clustering procedure, presented here as a genome-mining tool, “GEMINI.” GEMINI was validated on experimentally verified islands in the LESB58 strain before examining its potential to decipher novel islands. Of the 6062 genes in P. aeruginosa LESB58, 596 genes were identified to be resident on 20 GIs of which 12 have not been previously reported. Comparative genomics provided evidence in support of our novel predictions. Furthermore, GEMINI unraveled the mosaic structure of islands that are composed of segments of likely different evolutionary origins, and demonstrated its ability to identify potential strain biomarkers. These newly found islands likely have contributed to the hyper-virulence and multidrug resistance of the Liverpool epidemic strain of P. aeruginosa. PMID:27536294
Mantha, Sriteja; McDaniel, Jesse G; Perroni, Dominic V; Mahanthappa, Mahesh K; Yethiraj, Arun
2017-01-26
Gemini surfactants comprise two single-tailed surfactants connected by a linker at or near the hydrophilic headgroup. They display a variety of water-concentration-dependent lyotropic liquid crystal morphologies that are sensitive to surfactant molecular structure and the nature of the headgroups and counterions. Recently, an interesting dependence of the aqueous-phase behavior on the length of the linker has been discovered; odd-numbered linker length surfactants exhibit characteristically different phase diagrams than even-numbered linker surfactants. In this work, we investigate this "odd/even effect" using computer simulations, focusing on experimentally studied gemini dicarboxylates with Na + counterions, seven nonterminal carbon atoms in the tails, and either three, four, five, or six carbon atoms in the linker (denoted Na-73, Na-74, Na-75, and Na-76, respectively). We find that the relative electrostatic repulsion between headgroups in the different morphologies is correlated with the qualitative features of the experimental phase diagrams, predicting destabilization of hexagonal phases as the cylinders pack close together at low water content. Significant differences in the relative headgroup orientations of Na-74 and Na-76 compared to those of Na-73 and Na-75 surfactants lead to differences in linker-linker packing and long-range headgroup-headgroup electrostatic repulsion, which affects the delicate electrostatic balance between the hexagonal and gyroid phases. Much of the fundamental insight presented in this work is enabled by the ability to computationally construct and analyze metastable phases that are not observable in experiments.
[Fe II] emissions associated with the young interacting binary UY Aurigae
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pyo, Tae-Soo; Hayashi, Masahiko; Beck, Tracy L.
We present high-resolution 1.06-1.28 μm spectra toward the interacting binary UY Aur obtained with GEMINI/NIFS and the adaptive optics system Altair. We have detected [Fe II] λ1.257 μm and He I λ1.083 μm lines from both UY Aur A (the primary source) and UY Aur B (the secondary). In [Fe II] UY Aur A drives fast and widely opening outflows with an opening angle of ∼90° along a position angle of ∼40°, while UY Aur B is associated with a redshifted knot. The blueshifted and redshifted emissions show a complicated structure between the primary and secondary. The radial velocities ofmore » the [Fe II] emission features are similar for UY Aur A and B: ∼ –100 km s{sup –1} for the blueshifted emission and ∼ +130 km s{sup –1} for the redshifted component. The He I line profile observed toward UY Aur A comprises a central emission feature with deep absorptions at both blueshifted and redshifted velocities. These absorption features may be explained by stellar wind models. The He I line profile of UY Aur B shows only an emission feature.« less
GEMINI-TITAN (GT)-9 - EARTH-SKY VIEW - PERU - OUTER SPACE
1966-06-05
S66-38290 (5 June 1966) --- The north coastal area of Peru looking southeast across the Andes Mountains as seen from the National Aeronautics and Space Administration's Gemini-9A spacecraft. The body of water is the Pacific Ocean. The image was taken with a modified 70mm Hasselblad camera, using Eastman Kodak, Ektachrome MS (S.O. 217) color film. Photo credit: NASA
Space Food Package - Gemini-Titan (GT)-4 Flight - MSC
1965-05-01
Food packages of beef and gravy fully reconstituted and ready to eat. An astronaut would squeeze food through opening at right side of package. Water gun is used to reconstitute dehydrated food. Scissors are used to open packages. This is the type of space food which will be used on the Gemini-Titan 4 spaceflight. MSC, Houston, TX *S65-24895 thru S65-24899
Northwestern Mexico as seen from the Gemini 9-A spacecraft
NASA Technical Reports Server (NTRS)
1966-01-01
Northwestern Mexico as seen from the Gemini 9-A spacecraft during its 32nd revolution of the earth. Large peninsula is Baja California. Body of water at lower right is Pacific Ocean. Land mass at upper left is State of Sonora. Gulf of California separates Sonora from peninsula. Nose of spacecraft is at left and at right is open hatch of spacecraft.
Intra-Extra Vehicular Activity (IEVA) Russian and Gemini Spacesuits
NASA Technical Reports Server (NTRS)
Thomas, Kenneth S.
2016-01-01
Kenneth Thomas will discuss the Intra-Extra Vehicular Activity Russian and Gemini spacesuits. While the United States and Russia adapted to existing launch- and reentry-type suits to allow the first human ventures into the vacuum of space, there were differences in execution and capabilities. Mr. Thomas will discuss the advantages and disadvantages of this approach compared to exclusively intra-vehicular or extra-vehicular suit systems.
1966-05-09
S66-32629 (1966) --- Left to right are Dr. Charles A. Berry, MSC Medical Director; Dr. Donald K. (Deke) Slayton, Director of Flight Crew Operations; Eugene F. Kranz, Flight Director; Charles W. Mathews, Gemini Program Manager, Manned Spacecraft Center; William C. Schneider, Gemini Mission Manager, NASA Headquarters; General Leighton Davis; Dr. Robert R. Gilruth, MSC Director; and Dr. George E. Mueller, Associate Administrator for Manned Space Flight, NASA Headquarters.
Photograph of MSC-8 color patch outside spacecraft during docking
1966-07-18
S66-46025 (18 July 1966) --- Astronaut Michael Collins, Gemini-10 pilot, photographed this MSC-8 color patch outside the spacecraft during the Gemini-10/Agena docking mission. The experiment was for the purpose of showing what effect the environment of space will have upon the color photography taken in cislunar space and on the lunar surface during an Apollo mission. Photo credit: NASA
GEMINI-TITAN (GT)-9 - MOCKUP - ADAPTER EQUIPMENT SECTION - FUEL CELL - MSC
1966-03-01
S66-22686 (March 1966) --- Mock-up of the adapter equipment section to be used on the Gemini-9 spaceflight. This section provides volume and attach points for several system modules, including Orbit Attitude Maneuver System, Environmental Control System primary oxygen supply, batteries, coolant, and electrical and electric components. This section will also hold the Astronaut Maneuvering Unit (AMU) backpack (center). Photo credit: NASA
NASA Technical Reports Server (NTRS)
Charles, John B.
2017-01-01
Before Apollo fire, early Apollo missions were expected to continue pattern established in Gemini program of accommodating significant scientific and biological experimentation, including human biomedical studies, during flights. Apollo1 and Apollo2, both 2-week engineering test flights, were to carry almost as many biomedical studies as Gemini 7, a 2-week medical test mission.
GEMINI-TITAN (GT)-7 - PREFLIGHT PHYSICAL - ASTRONAUT FRANK BORMAN - CAPE
1965-12-02
S65-60603 (2 Dec. 1965) --- Astronaut Frank Borman, Gemini-7 command pilot, sits attentively as two scalp electrodes are attached to his head. The electrodes will allow doctors to record electrical activity of the astronaut's cerebral cortex during periods of weightlessness. The objectives of this in-flight experiment are to assess state of alertness, levels of consciousness, and depth of sleep. Photo credit: NASA
Linking Deep Astrometric Standards to the ICRF
NASA Astrophysics Data System (ADS)
Frey, S.; Platais, I.; Fey, A. L.
2007-07-01
The next-generation large aperature and large field-of-view telescopes will address fundamantal questions of astrophysica and cosmology such as the nature of dark matter and dark energy. For a variety of applications, the CCD mosaic detectors in the focal plane arrays require astronomic calibrationat the milli-arcsecond (mas) level. The existing optical reference frames are insufficient to support such calibrations. To address this problem, deep optical astronomic fields are being established near the Galactic plane. In order to achiev a 5-10-mas or better positional accuracyfor the Deepp Astrometric Standards (DAS), and to obtain bsolute stellar proper motions for the study of Galactic structure, it is crucial to link these fields to the International Celestial Reference Frame (ICRF). To this end, we selected 15 candidate compact extragalactic radio sources in the Gemini-Orion-Taurus (GOT) field. These sources were observed with the European VLBI Network (EVN) at 5 GHz in phase-reference mode. The bright compact calibrator source J0603+2159 and seven other sources were detected and imaged at the angular resolution of -1.5-8 mas. Relative astrometric positions were derived for these sources at a milli-arcsecond accuracy level. The detection of the optical counterparts of these extragalactic radio sources will allow us to establish a direct link to the ICRF locally in the GOT field.
Bai, Guangyue; Wu, Hui; Lou, Pengxiao; Wang, Yujie; Nichifor, Marieta; Zhuo, Kelei; Wang, Jianji; Bastos, Margarida
2017-01-04
Understanding the thermodynamics of formation of biocompatible aggregates is a key factor in the bottom up approach to the development of novel types of drug carriers and their structural tuning using small amphiphilic molecules. We chose an anionic amphiphilic and biocompatible polymer that consists of a dextran and grafted cholic acid pendants, randomly distributed along the dextran backbone, with a degree of substitution (DS) of 15 mol% (designated Dex-15CACOONa). The thermodynamics of interaction and phase behavior of mixtures of this polyelectrolyte and a cationic gemini surfactant hexanediyl-α,ω-bis(dodecyldimethylammonium bromide) (C 12 C 6 C 12 Br 2 ) or its monomer surfactant dodecyltrimethylammonium bromide (DTAB) in aqueous solution were characterized by isothermal titration calorimetry (ITC) and turbidity, together with cryogenic transmission electron microscopy (Cryo-TEM). The various critical concentrations and the enthalpy changes of the corresponding phase transitions for the oppositely charged system were obtained from the plots of the observed enthalpy change (ΔH obs ) and turbidity measurements as a function of gemini concentration. The morphologies of the aggregates in various phases were observed by Cryo-TEM. Altogether these results suggest the critical role of gemini as a dual linker. At the concentrations where the crosslink between the pendant aggregates happens, the free gemini concentration is proximately zero and the aggregate retains its negative charge. The analysis of various factors involved in the interaction allowed a rationalization of the driving forces for mixed aggregate formation, which will contribute to a subsequent rational design of drug delivery systems based on this polymer/surfactant system.
NASA Astrophysics Data System (ADS)
Chang, Wengui; Shen, Yuhua; Xie, Anjian; Liu, Xue
2010-04-01
Gemini surfactants, double sodium α-sulfonic polyethylene glycol laurate (abbreviated C 12-PEG-C 12), were prepared and applied as soft templates in the controlled synthesis of BaCrO 4 and PbCrO 4 micro/nanocrystals. The template effects were investigated by adjusting the length of the spacer, using PEG400 and PEG4000, of the Gemini surfactant. The results indicated that the size and morphology of BaCrO 4 and PbCrO 4 micro/nanocrystals varied with the change in spacer length of C 12-PEG-C 12, suggesting that the different lengths of the polyethylene glycol group spacers in the Gemini surfactants played a key role in determining the size and shape of the MCrO 4 micro/nanoparticles. The dynamic process of the formation of the novel morphology BaCrO 4 crystals showed that the morphology grew from a round-bar polyhedron, to regular polyhedron, to approximate octahedron to a uniform pistachio nut shape. The growth mechanism of the BaCrO 4 micro/nanocrystals was explained that C 12-PEG-C 12 had a greater interfacial adsorption and would effectively control the shape evolution during the crystal growth, while PbCrO 4 could be explained that the Gemini surfactants can undergo liquid-crystalline phase transitions with long channels providing a soft template effect and derived the nanorods formation. Room temperature fluorescence spectra were studied and these showed that the pistachio-shaped BaCrO 4 microcrystals and PbCrO 4 nanorods possess photoactive luminescence properties with emission peaks at 470 and 549 nm, respectively.
1966-09-09
This is the official NASA portrait of astronaut James Lovell. Captain Lovell was selected as an Astronaut by NASA in September 1962. He has since served as backup pilot for the Gemini 4 flight and backup Commander for the Gemini 9 flight, as well as backup Commander to Neil Armstrong for the Apollo 11 lunar landing mission. On December 4, 1965, he and Frank Borman were launched into space on the history making Gemini 7 mission. The flight lasted 330 hours and 35 minutes and included the first rendezvous of two manned maneuverable spacecraft. The Gemini 12 mission, commanded by Lovell with Pilot Edwin Aldrin, began on November 11, 1966 for a 4-day, 59-revolution flight that brought the Gemini program to a successful close. Lovell served as Command Module Pilot and Navigator on the epic six-day journey of Apollo 8, the first manned Saturn V liftoff responsible for allowing the first humans to leave the gravitational influence of Earth. He completed his fourth mission as Spacecraft Commander of the Apollo 13 flight, April 11-17, 1970, and became the first man to journey twice to the moon. The Apollo 13 mission was cut short due to a failure of the Service Module cryogenic oxygen system. Aborting the lunar course, Lovell and fellow crewmen, John L. Swigert and Fred W. Haise, working closely with Houston ground controllers, converted their lunar module, Aquarius, into an effective lifeboat that got them safely back to Earth. Captain Lovell held the record for time in space with a total of 715 hours and 5 minutes until surpassed by the Skylab flights. On March 1, 1973, Captain Lovell retired from the Navy and the Space Program.
Zakharova, Lucia Ya; Gabdrakhmanov, Dinar R; Ibragimova, Alsu R; Vasilieva, Elmira A; Nizameev, Irek R; Kadirov, Marsil K; Ermakova, Elena A; Gogoleva, Natalia E; Faizullin, Dzhigangir A; Pokrovsky, Andrey G; Korobeynikov, Vladislav A; Cheresiz, Sergey V; Zuev, Yuriy F
2016-04-01
Gemini surfactants with hexadecyl tails and hydroxyethylated head groups bridged with tetramethylene (G4), hexamethylene (G6) and dodecamethylene (G12) spacers were shown to self-assemble at the lower critical micelle concentration compared to their conventional m-s-m analogs. The lipoplex formation and the plasmid DNA transfer into different kinds of host cells were studied. In the case of eukaryotic cells, high transfection efficacy has been demonstrated for DNA-gemini complexes, which increased as follows: G6
Constraints on the architecture of the HD 95086 planetary system with the Gemini Planet Imager
Rameau, Julien; Nielsen, Eric L.; De Rosa, Robert J.; ...
2016-05-06
Here, we present astrometric monitoring of the young exoplanet HD 95086 b obtained with the Gemini Planet Imager between 2013 and 2016. A small but significant position angle change is detected at constant separation; the orbital motion is confirmed with literature measurements. Efficient Monte Carlo techniques place preliminary constraints on the orbital parameters of HD 95086 b. With 68% confidence, a semimajor axis ofmore » $${61.7}_{-8.4}^{+20.7}$$ au and an inclination of $$153° {0}_{-13.5}^{+9.7}$$ are favored, with eccentricity less than 0.21. Under the assumption of a coplanar planet–disk system, the periastron of HD 95086 b is beyond 51 au with 68% confidence. Therefore, HD 95086 b cannot carve the entire gap inferred from the measured infrared excess in the SED of HD 95086. We use our sensitivity to additional planets to discuss specific scenarios presented in the literature to explain the geometry of the debris belts. We suggest that either two planets on moderately eccentric orbits or three to four planets with inhomogeneous masses and orbital properties are possible. As a result, the sensitivity to additional planetary companions within the observations presented in this study can be used to help further constrain future dynamical simulations of the planet–disk system.« less
GEMINI-TITAN (GT)-11 - MISC. - EXPERIMENT D-16 - KNEE TETHER - MSC
1966-01-28
S66-00933 (28 Jan. 1966) --- Gemini-11 Experiment D-16 Knee Tether, sponsored by the Department of Defense and the United States Air Force. The astronaut tightens and loosens bolts in a prescribed pattern during his extravehicular activity, once with his body held to the spacecraft by a nine-inch tether looped around his knee and through the handrail, and once without the tether. Photo credit: NASA
GEMINI-TITAN (GT)-11 - EARTH SKY - OUTER SPACE
1966-09-14
S66-54706 (14 Sept. 1966) --- Western half of Australia, including the coastline from Perth to Port Darwin, looking west, as seen from the Gemini-11 spacecraft during its 26th revolution of Earth. Photograph was made while the spacecraft was at a record-high apogee of 740 nautical miles. Taken with a modified 70mm Hasselblad camera, using Eastman Kodak, Ektachrome, MS (S.O. 368) color film. Photo credit: NASA
Northwestern Mexico as seen from the Gemini 12 spacecraft
NASA Technical Reports Server (NTRS)
1966-01-01
Area of northwestern Mexico as seen from the Gemini 12 spacecraft during its 16th revolution of the earth. View is looking northwest. Body of water in foreground is Gulf of California. Pacific Ocean is in background. Peninsula in center of picture is Baja California. States of Sonora (upper right) and Sinaloa (lower center) of Mexican mainland is in right foreground. City of Guaymas, Sonora, is near center of picture.
PRELAUNCH - GEMINI-TITAN (GT)-12 - LEAVE TRAILER - CAPE
1966-11-11
S66-59916 (11 Nov. 1966) --- Prime crew for the Gemini-12 spaceflight, astronauts James A. Lovell Jr. (leading), command pilot, and Edwin E. Aldrin Jr., pilot, leave the suiting trailer at Launch Complex 16 during prelaunch countdown. Moments later they entered a transport van which carried them to Pad 19 and their waiting spacecraft. The liftoff was at 3:46 p.m. (EST), Nov. 11, 1966. Photo credit: NASA
Catanionic mixtures forming gemini-like amphiphiles.
Sakai, Hideki; Okabe, Yuji; Tsuchiya, Koji; Sakai, Kenichi; Abe, Masahiko
2011-01-01
The properties of aqueous mixtures of cationic species with alkyl dicarboxylic acid compounds have been studied. The cationic compounds used in this study were tertiary amine-type N-methyl-N-(2,3-dioxypropyl)hexadecylamine (C16amine) and quaternary ammonium-type N,N-dimethyl-N-(2,3-dioxypropyl)hexadecylammonium chloride (C16Q). The alkyl dicarboxylic acid compounds used were HOOC(CH(2))(10)COOH (C12H) and its sodium salt (C12Na). Three aqueous mixtures were examined in this study: (System I) C16amine + C12H, (System II) C16Q + C12Na, and (System III) C16Q + C12H. The solution pH was set at 12 for System III. The combination of (1)H-NMR and mass spectroscopy data has suggested that a stoichiometric complex is formed in the aqueous solutions at a mole fraction of C12H (or C12Na) = 0.33. Here, the C12H (or C12Na) molecule added to the system bridges two cationic molecules, like a spacer of gemini surfactants. In fact, the static surface tensiometry has demonstrated that the stoichiometric complex behaves as gemini-like amphiphiles in aqueous solutions. Our current study offers a possible way for easily preparing gemini surfactant systems.
Hawaii's Annual Journey through the Universe Program
NASA Astrophysics Data System (ADS)
Harvey, J.; Michaud, P.
2013-04-01
Hawaii's eighth annual Journey through the Universe, Gemini North's flagship local outreach program, engaged local as well as a host of visiting astronomy educators from across the country. Seventy-two educators enlightened over 8,000 students at 20 schools while visiting over 380 classrooms during “Journey Week” 2012. Gemini and the local observatories on Mauna Kea, the National Lunar Science Institute, the University of Hawai‘i at Hilo, ‘Imiloa Astronomy Education Center and Hawaii's Department of Education made this possible and are currently working to further extend the Journey program. The next phase of the nationally recognized educational outreach initiative, Journey 2.0, continues to include assessment and will explore the viability of funding for longitudinal studies on both students and teachers. New in 2012, we invited the public to join the astronomers, teacher and principals for a one-day STEM workshop which featured a keynote address: “Science—It's Not a Book of Knowledge… It's a Journey” led by Dr. Jeff Goldstein, Director of the National Center for Earth and Space Science Education and founder of the national Journey through the Universe program. The 2013 Journey program is scheduled for March 7-13, 2013. More information for this program can be found online at www.gemini.edu/journey.
Potential Interference from Wireless Water Tank Transmitters at Goldstone
NASA Astrophysics Data System (ADS)
Ho, C.
2008-02-01
The Deep Space Network (DSN) facility in the Goldstone, California, area is considering installation of a new type of wireless transmitter (M2400S) within the facility. The transmitters will be used to monitor the water levels in several water tanks. Then these water-level signals will be transmitted to the nearby DSN facilities using transmitters operating in the UHF band (900-MHz) or S-band (2.4-GHz). This study is to evaluate the interference effects from the transmitters in adjacent DSN receiving stations. First we perform a terrain profile analysis to identify if there is a line of sight between each transmitter and the nearby DSN stations. After taking into account terrain shielding using high-resolution data, total propagation losses are calculated along each path. Then we perform the link analysis for each site to identify if the interference power exceeds the protection threshold of DSN receiving stations. As a result, we find that, because there is no bandpass filter installed in the transmitter system, interference power from the new transmitter at S-band will greatly exceed the protection criteria of broadband radio astronomy services (RAS) at S-band, such as Deep Space Station (DSS) 12 and DSS 28, by about 50 dB. The interference may also cause problems on all deep-space research stations at S-band, such as the Mars, Apollo, Venus, and Gemini sites. Without a sharp bandpass filter to suppress the out-of-band emissions in the frequency bands that the DSN station and RAS use, the author recommends not installing this type of transmitter within the Goldstone DSN facility area.
NASA Astrophysics Data System (ADS)
Chilcote, Jeffrey Kaplan
This thesis is focused on the development and testing of a new instrument capable of finding and characterizing recently-formed Jupiter-sized planets orbiting other stars. To observe these planets, I present the design, construction and testing of the Gemini Planet Imager (GPI) Integral Field Spectrograph (IFS). GPI is a facility class instrument for the Gemini Observatory with the primary goal of directly detecting young Jovian planets. The GPI IFS utilizes an infrared transmissive lenslet array to sample a rectangular 2.7 x 2.7 arcsecond field of view and provide low-resolution spectra across five bands between 1 and 2.5 mum. The dispersing element can be replaced with a Wollaston prism to provide broadband polarimetry across the same five filter bands. The IFS construction was based at the University of California, Los Angeles in collaboration with the Universite de Montreal, Immervision and Lawrence Livermore National Laboratory. I will present performance results, from in-lab testing, of the Integral Field Spectrograph (IFS) for the Gemini Planet Imager (GPI). The IFS is a large, complex, cryogenic, optical system requiring several years of development and testing. I will present the design and integration of the mechanical and optical performance of the spectrograph optics. The IFS passed its pre-ship review in 2011 and was shipped to University of California, Santa Cruz for integration with the remaining sub-systems of GPI. The UCLA built GPI IFS was integrated with the rest of GPI and is delivering high quality spectral datacubes of GPI's coronagraphic field. Using the NIRC2 instrument located at the Keck Observatory, my collaborators and I observed the planetary companion to beta Pictoris in L' (3.5--4.1mum). Observations taken in the fall of 2009 and 2012 are used to find the location and inclination of the planet relative to the massive debris disk orbiting beta Pictoris. We find that the planet's orbit has a position angle on the sky of 211.9+/-0.4 degrees, making the planet misaligned by 2.9+/-0.5 degrees from the main disk, consistent with other observations that beta Pic b is misaligned with the main disk, and part of the misaligned inner disk. In 2009 & 2012 we find a projected orbital separation of 312.8 +/- 18.3 and 466.35 +/- 8.4 milliarcseconds consistent with an orbital period of ˜ 20 years, and a semi-major axis of ˜ 9 AU as found by Macintosh et al. (2014). During the first commissioning observations with the Gemini Planet Imager (GPI), my collaborators and I took the first H-band spectrum of the planetary companion to the nearby young star beta Pictoris. The spectrum has a resolving power of ˜ 45 and demonstrates the distinctive triangular shape of a cool substellar object with low surface gravity. Using atmospheric models, we find an effective temperature of 1650 +/- 50K and a surface gravity of log(g) = 4.0 +/- 0.25 (cgs units). These values agree well with predictions from planetary evolution models for a gas giant with mass between 10 and 12 MJup and age between 10 and 20 Myrs. The spectrum is very similar to a known low mass field brown dwarf but has more flux at the long wavelength end of the filters compared to models. Given the very high signal-to-noise of our spectrum this likely indicates additional physics such as patchy clouds that need to be included in the model.
The Gemini Planet Imager Exoplanet Survey
NASA Astrophysics Data System (ADS)
Nielsen, Eric L.; Macintosh, Bruce; Graham, James R.; Barman, Travis S.; Doyon, Rene; Fabrycky, Daniel; Fitzgerald, Michael P.; Kalas, Paul; Konopacky, Quinn M.; Marchis, Franck; Marley, Mark S.; Marois, Christian; Patience, Jenny; Perrin, Marshall D.; Oppenheimer, Rebecca; Song, Inseok; GPIES Team
2017-01-01
The Gemini Planet Imager Exoplanet Survey (GPIES) is one of the largest most sensitive direct imaging searches for exoplanets conducted to date, and having observed more than 300 stars the survey is halfway complete. We present highlights from the first half of the survey, including the discovery and characterization of the young exoplanet 51 Eri b and the brown dwarf HR 2562 B, new imaging of multiple disks, and resolving the young stellar binary V343 Nor for the first time. GPI has also provided new spectra and orbits of previous known planets and brown dwarfs and polarization measurements of a wide range of disks. Finally, we discuss the constraints placed by the first half of the GPIES campaign on the population of giant planets at orbital separations beyond that of Jupiter. Supported by NSF grants AST-0909188 and AST-1313718, AST-1411868, AST 141378, NNX11AF74G, and DGE-1232825, and by NASA grants NNX15AD95G/NEXSS and NNX11AD21G.
Internal kinematic and physical properties in a BCD galaxy: Haro 15 in detail
NASA Astrophysics Data System (ADS)
Firpo, V.; Bosch, G.; Hägele, G. F.; Díaz, A. I.; Morrell, N.
2011-11-01
We present a detailed study of the kinematic and physical properties of the ionized gas in multiple knots of the blue compact dwarf galaxy Haro 15. Using echelle and long slit spectroscopy data, obtained with different instruments at Las Campanas Observatory, we study the internal kinematic and physical conditions (electron density and temperature), ionic and total chemical abundances of several atoms, reddening and ionization structure. Applying direct and empirical methods for abundance determination, we perform a comparative analysis between these regions and in their different components. On the other hand, our echelle spectra show complex kinematics in several conspicuous knots within the galaxy. To perform an in-depth 2D spectroscopic study we complete this work with high spatial and spectral resolution spectroscopy using the Integral Field Unit mode on the Gemini Multi-Object Spectrograph instrument at the Gemini South telescope. With these data we are able to resolve the complex kinematical structure within star forming knots in Haro 15 galaxy.
VizieR Online Data Catalog: SPT-SZ survey galaxy clusters optical spectroscopy (Ruel+, 2014)
NASA Astrophysics Data System (ADS)
Ruel, J.; Bazin, G.; Bayliss, M.; Brodwin, M.; Foley, R. J.; Stalder, B.; Aird, K. A.; Armstrong, R.; Ashby, M. L. N.; Bautz, M.; Benson, B. A.; Bleem, L. E.; Bocquet, S.; Carlstrom, J. E.; Chang, C. L.; Chapman, S. C.; Cho, H. M.; Clocchiatti, A.; Crawford, T. M.; Crites, A. T.; de Haan, T.; Desai, S.; Dobbs, M. A.; Dudley, J. P.; Forman, W. R.; George, E. M.; Gladders, M. D.; Gonzalez, A. H.; Halverson, N. W.; Harrington, N. L.; High, F. W.; Holder, G. P.; Holzapfel, W. L.; Hrubes, J. D.; Jones, C.; Joy, M.; Keisler, R.; Knox, L.; Lee, A. T.; Leitch, E. M.; Liu, J.; Lueker, M.; Luong-van, D.; Mantz, A.; Marrone, D. P.; McDonald, M.; McMahon, J. J.; Mehl, J.; Meyer, S. S.; Mocanu, L.; Mohr, J. J.; Montroy, T. E.; Murray, S. S.; Natoli, T.; Nurgaliev, D.; Padin, S.; Plagge, T.; Pryke, C.; Reichardt, C. L.; Rest, A.; Ruhl, J. E.; Saliwanchik, B. R.; Saro, A.; Sayre, J. T.; Schaffer, K. K.; Shaw, L.; Shirokoff, E.; Song, J.; Suhada, R.; Spieler, H. G.; Stanford, S. A.; Staniszewski, Z.; Starsk, A. A.; Story, K.; Stubbs, C. W.; van Engelen, A.; Vanderlinde, K.; Vieira, J. D.; Vikhlinin, A.; Williamson, R.; Zahn, O.; Zenteno, A.
2017-04-01
Most of the galaxy clusters for which we report spectroscopic observations were published as SPT cluster detections (and new discoveries) in Vanderlinde et al. (2010ApJ...722.1180V), Williamson et al. (2011ApJ...738..139W), and Reichardt et al. (2013, J/ApJ/763/127); we refer the reader to those publications for details of the SPT observations. The spectroscopic observations presented in this work are the first of our ongoing follow-up program. The data were taken from 2008 to 2012 using the Gemini Multi Object Spectrograph (GMOS; Hook et al. 2004PASP..116..425H) on Gemini South, the Focal Reducer and low dispersion Spectrograph (FORS2; Appenzeller et al. 1998Msngr..94....1A) on VLT Antu, the Inamori Magellan Areal Camera and Spectrograph (IMACS; Dressler et al. 2006SPIE.6269E..0FD) on Magellan Baade, and the Low Dispersion Survey Spectrograph (LDSS339; Allington-Smith et al. 1994PASP..106..983A) on Magellan Clay. (2 data files).
NASA Technical Reports Server (NTRS)
Fischer, Travis C.; Machuca, C.; Diniz, M. R.; Crenshaw, D. M.; Kraemer, S. B.; Riffel, R. A.; Schmitt, H. R.; Baron, F.; Storchi-Bergmann, T.; Straughn, A. N.;
2016-01-01
We present near-infrared and optical emission-line and stellar kinematics of the Seyfert 2 galaxy Mrk 573 using the Near-Infrared Field Spectrograph (NIFS) at Gemini North and Dual Imaging Spectrograph at Apache Point Observatory, respectively. By obtaining full kinematic maps of the infrared ionized and molecular gas and stellar kinematics in approximately 700 x 2100 pc(exp 2) circumnuclear region of Mrk 573, we find that kinematics within the Narrow-Line Region are largely due to a combination of both rotation and in situ acceleration of material originating in the host disk. Combining these observations with large-scale, optical long-slit spectroscopy that traces ionized gas emission out to several kpcs, we find that rotation kinematics dominate the majority of the gas. We find that outflowing gas extends to distances less than 1 kpc, suggesting that outflows in Seyfert galaxies may not be powerful enough to evacuate their entire bulges.
Ways of achieving continuous service from computers
NASA Technical Reports Server (NTRS)
Quinn, M. J., Jr.
1974-01-01
This paper outlines the methods used in the real-time computer complex to keep computers operating. Methods include selectover, high-speed restart, and low-speed restart. The hardware and software needed to implement these methods is discussed as well as the system recovery facility, alternate device support, and timeout. In general, methods developed while supporting the Gemini, Apollo, and Skylab space missions are presented.
VizieR Online Data Catalog: Subarcsecond mid-infrared atlas of local AGN (Asmus+, 2014)
NASA Astrophysics Data System (ADS)
Asmus, D.; Hoenig, S. F.; Gandhi, P.; Smette, A.; Duschl, W. J.
2014-03-01
The Subarcsecond mid-infrared (MIR) atlas of local active galactic nuclei (AGN) is a collection of all available N- and Q-band images obtained at ground-based 8-meter class telescopes with public archives (Gemini/Michelle, Gemini/T-ReCS, Subaru/COMICS, and VLT/VISIR). It includes in total 895 images, of which 60% are perviously unpublished. These correspond to 253 local AGN with a median redshift of 0.016. The atlas contains the uniformly processed and calibrated images and nuclear photometry obtained through Gauss and PSF fitting for all objects and filters. This also includes measurements of the nuclear extensions. In addition, the classifications of extended emission (if present) and derived nuclear monochromatic 12 and 18 micron continuum fluxes are available. Finally, flux ratios with the circumnuclear MIR emission (measured by Spitzer) and total MIR emission of the galaxy (measured by IRAS) are presented. The observations have been taken in the mid-infrared (N-band, 7-13micron, and Q-band, 17-20micron) between 2003-12-02 and 2011-06-15 and cover the whole sky. The objects have redshifts between -0.0001 and 0.3571. (2 data files).
NASA Technical Reports Server (NTRS)
Muzzin, Adam; Wilson, Gillian; Yee, H.K.C.; Hoekstra, Henk; Gilbank, David; Surace, Jason; Lacy, Mark; Blindert, Kris; Majumdar, Subhabrata; Demarco, Ricardo;
2008-01-01
The Spitzer Adaptation of the Red-sequence Cluster Survey (SpARCS) is a deep z -band imaging survey covering the Spitzer SWIRE Legacy fields designed to create the first large homogeneously-selected sample of massive clusters at z > 1 using an infrared adaptation of the cluster red-sequence method. We present an overview of the northern component of the survey which has been observed with CFHT/MegaCam and covers 28.3 deg(sup 2). The southern component of the survey was observed with CTIO/MOSAICII, covers 13.6 deg(sup 2), and is summarized in a companion paper by Wilson et al. (2008). We also present spectroscopic confirmation of two rich cluster candidates at z approx. 1.2. Based on Nod-and- Shuffle spectroscopy from GMOS-N on Gemini there are 17 and 28 confirmed cluster members in SpARCS J163435+402151 and SpARCS J163852+403843 which have spectroscopic redshifts of 1.1798 and 1.1963, respectively. The clusters have velocity dispersions of 490 +/- 140 km/s and 650 +/- 160 km/s, respectively which imply masses (M(sub 200)) of (1.0 +/- 0.9) x 10(exp 14) Stellar Mass and (2.4 +/- 1.8) x 10(exp 14) Stellar Mass. Confirmation of these candidates as bonafide massive clusters demonstrates that two-filter imaging is an effective, yet observationally efficient, method for selecting clusters at z > 1.
1965-10-25
S65-57967 (25 Oct. 1965) --- View at Pad 14 during prelaunch operations for the Atlas/Agena. The Agena is mounted atop its Atlas launch vehicle. The Atlas/Agena liftoff was at 10 a.m. (EST) on Oct. 25, 1965. Intended as a rendezvous target vehicle in the Gemini-6 mission, the Agena failed to achieve orbit, and the Oct. 25 Gemini-6 launch was scrubbed. Photo credit: NASA or National Aeronautics and Space Administration
GEMINI-TITAN (GT)-10 (RECOVERY) - ASTRONAUT JOHN W. YOUNG - MISC. - ATLANTIC
1966-07-21
S66-42772 (21 July 1966) --- A U.S. Navy frogman assist the Gemini-10 crew following splashdown at 4:07 p.m. (EST), July 21, 1966, about four miles from the recovery ship, USS Guadalcanal. Astronaut John W. Young (climbing from spacecraft), command pilot, and Michael Collins (in spacecraft), pilot, were later hoisted from the water by a recovery helicopter and flown to the Guadalcanal. Photo credit: NASA
ISSION CONTROL CENTER (MCC) - GEMINI-TITAN (GT)-IV - MSC
1965-06-03
S65-30411 (9 June 1965) --- The families of Gemini 4 astronauts James A. McDivitt and Edward H. White II visited the Mission Control Center in Houston. In the foreground, left to right, are Mrs. Patricia McDivitt, daughter Bonnie White, Mrs. Patricia White, flight director Christopher C. Kraft Jr., and Edward White III. Each of the family members talked with the astronauts as they passed over the United States. Photo credit: NASA
1965-12-07
S65-63784 (7 Dec. 1965) --- Algeria, south of Celemb Bechar, as seen from the orbiting Gemini-7 spacecraft during its 42nd revolution of Earth. Note rain runoff on the desert floor. Astronaut Frank Borman and James A. Lovell Jr. were aboard the National Aeronautics and Space Administration?s Gemini-7 spacecraft. The photograph was taken with a modified 70mm Hasselblad camera, using Eastman Kodak, Ektachrome MS (S.O. 217) color film. Photo credit: NASA
Berry examines Lovell following a workout on exercise machine
1965-12-02
S65-60602 (2 Dec. 1965) --- Dr. Charles A. Berry checks astronaut James A. Lovell Jr., Gemini-7 prime crew pilot, following a workout on an exercise machine. Results will be compared with those obtained during spaceflight for evaluation. Lovell and astronaut Frank Borman (not pictured), command pilot, will pilot the Gemini-7 spacecraft on a planned 14-day mission. Dr. Berry is chief, MSC Center Medical Programs. Photo credit: NASA
Gemini Observatory Takes its Local Communities on an Expanding Journey
NASA Astrophysics Data System (ADS)
Harvey, Janice; Michaud, Peter
2012-08-01
Currently in its 7th year (2011) Hawaii's annual Journey through the Universe (JttU) program is a flagship Gemini Observatory public education/outreach initiative involving a broad cross-section of the local Hawai'i Island astronomical community, the public, educators, businesses, local government officials, and thousands of local students. This paper describes the program, its history, planning, implementation, as well as the program's objectives and philosophy. The success of this program is documented here, as measured by continuous and expanding engagement of educators, the community, and the public, along with formal evaluation feedback and selected informal verbal testimony. The program's success also serves as justification for the planned adaptation of a version of the program in Chile in 2011 (adapted for Chilean educational and cultural differences). Finally, lessons learned are shared which have refined the program for Gemini's host communities but can also apply to any institution wishing to initiate a similar program.
Gemini IV Mission Image - EVA over Texas coast
1965-06-03
View of Astronaut Edward H. White II, pilot for the Gemini-Titan 4 space flight, as he floats in zero gravity of space. The extravehicular activity was performed during the third revolution of the Gemini 4 spacecraft. White is attached to the spacecraft by a 25-ft. umbilical line and a 23-ft. tether line,both wrapped in gold tape to form one cord. In his right hand White carries a Hand-Held Self-Maneuvering Unit (HHSMU). The visor of his helmet is gold plated to protect him from the unfiltered rays of the sun. Photo was taken on June 3,1965. G.E.T. time was 4:45 / GMT time was 20:00. Original magazine number was GEM04-16-34642, taken with a Hasselblad camera and a 70mm lens. Film type was Kodak Ektachrome MS (S.O. -217). The original photo was a color negative. It's image number is S65-34642.
Astronaut Ed White - Gemini-4 Extravehicular Activity (EVA)
1965-01-01
S65-30432 (3 June 1965) --- Astronaut Edward H. White II, pilot of the Gemini IV four-day Earth-orbital mission, floats in the zero gravity of space outside the Gemini IV spacecraft. White wears a specially designed spacesuit; and the visor of the helmet is gold plated to protect him against the unfiltered rays of the sun. He wears an emergency oxygen pack, also. He is secured to the spacecraft by a 25-feet umbilical line and a 23-feet tether line, both wrapped in gold tape to form one cord. In his right hand is a Hand-Held Self-Maneuvering Unit (HHSMU) with which he controls his movements in space. Astronaut James A. McDivitt, command pilot of the mission, remained inside the spacecraft. EDITOR'S NOTE: Astronaut White died in the Apollo/Saturn 204 fire at Cape Kennedy on Jan. 27, 1967.
ASTRONAUT WHITE, EDWARD - GEMINI-TITAN (GT)-4 - EXTRAVEHICULAR ACTIVITY (EVA)
1965-01-01
S65-30433 (3 June 1965) --- Astronaut Edward H. White II, pilot of the Gemini IV four-day Earth-orbital mission, floats in the zero gravity of space outside the Gemini IV spacecraft. White wears a specially designed spacesuit; and the visor of the helmet is gold plated to protect him against the unfiltered rays of the sun. He wears an emergency oxygen pack, also. He is secured to the spacecraft by a 25-feet umbilical line and a 23-feet tether line, both wrapped in gold tape to form one cord. In his right hand is a Hand-Held Self-Maneuvering Unit (HHSMU) with which he controls his movements in space. Astronaut James A. McDivitt, command pilot of the mission, remained inside the spacecraft. Photo credit: NASA EDITOR'S NOTE: Astronaut White died in the Apollo/Saturn 204 fire at Cape Kennedy on Jan. 27, 1967.
Astronaut Edward White - Gemini IV Extravehicular Activity (EVA)
1965-01-01
S65-30429 (3 June 1965) --- Astronaut Edward H. White II, pilot of the Gemini IV four-day Earth-orbital mission, floats in the zero gravity of space outside the Gemini IV spacecraft. White wears a specially designed spacesuit; and the visor of the helmet is gold plated to protect him against the unfiltered rays of the sun. He wears an emergency oxygen pack, also. He is secured to the spacecraft by a 25-feet umbilical line and a 23-feet tether line, both wrapped in gold tape to form one cord. In his right hand is a Hand-Held Self-Maneuvering Unit (HHSMU) with which he controls his movements in space. Astronaut James A. McDivitt, command pilot of the mission, remained inside the spacecraft. Photo credit: NASA EDITOR'S NOTE: Astronaut White died in the Apollo/Saturn 204 fire at Cape Kennedy on Jan. 27, 1967.
VizieR Online Data Catalog: Virgo cluster ETGs: GC and galaxy diffuse light (Li+, 2015)
NASA Astrophysics Data System (ADS)
Li, B.; Peng, E. W.; Zhang, H.-X.; Blakeslee, J. P.; Cote, P.; Ferrarese, L.; Jordan, A.; Liu, C.; Mei, S.; Puzia, T. H.; Takamiya, M.; Trancho, G.; West, M. J.
2017-09-01
We selected four intermediate-luminosity ETGs from the ACS Virgo Cluster Survey (ACSVCS; Cote et al. 2004, J/ApJS/153/223), a homogeneous Hubble Space Telescope survey of 100 ETGs in the nearby Virgo cluster of galaxies using the Advanced Camera for Surveys (ACS; Ford et al. 1998SPIE.3356..234F). We observed these galaxies with the Gemini Multi-Object Spectrographs (GMOS, Hook et al. 2004PASP..116..425H), twin instruments on the Gemini North and Gemini South telescopes. Our target galaxies have sizes (Re~10-18") that fit well within the GMOS field of view (5.5 arcmin2), providing coverage out to 10-16Re. Each galaxy contained ~50 targetable GCs with V<23 mag. VCC 1231, VCC 1062, and VCC 2000 data were taken with GMOS-South, whereas data for VCC 685 was taken with GMOS-North. (3 data files).
NASA Astrophysics Data System (ADS)
Madrid, Juan P.; Lee-Waddell, Karen; Serra, Paolo; Koribalski, Bärbel S.; Schirmer, Mischa; Spekkens, Kristine; Wang, Jing
2018-02-01
Using the Gemini Multi Object Spectrograph (GMOS) we search for optical counterparts of two massive (∼109 M ⊙) neutral hydrogen clouds near the spiral galaxy IC 5270, located in the outskirts of the IC 1459 group. These two H I clouds were recently discovered using the Australian Square Kilometer Array Pathfinder (ASKAP). Two low surface brightness optical counterparts to one of these H I clouds are identified in the new Gemini data that reaches down to magnitudes of ∼27.5 mag in the g-band. The observed H I mass-to-light ratio derived with these new data, {M}{{H}{{I}}}/{L}g=242, is among the highest reported to date. We are also able to rule out that the two H I clouds are dwarf companions of IC 5270. Tidal interactions and ram pressure stripping are plausible explanations for the physical origin of these two clouds.
Reverse micellar extraction of bromelain from pineapple peel--Effect of surfactant structure.
Wan, Jing; Guo, Jingjing; Miao, Zhitong; Guo, Xia
2016-04-15
Pineapple peel is generally disposed or used as compost. This study was focused on extracting bromelain from pineapple peel by using reverse micelles. It was found that gemini surfactant C12-8-C12·2Br (octamethylene-α,ω-bis(dimethyldodecylammonium bromide)) showed distinctive advantage over its monomeric counterpart DTAB (dodecyl trimethyl ammonium bromide); under optimized condition, the bromelain extracted with C12-8-C12·2Br reverse micelle had an activity recovery of 163% and a purification fold of 3.3, while when using DTAB reverse micelle, the activity recovery was 95% and the purification fold was 1.7. Therefore, the spacer of gemini surfactant should play a positive role in bromelain extraction and may suggest the potential of gemini surfactant in protein separation since it has been so far rarely used in relative experiments or technologies. Copyright © 2015 Elsevier Ltd. All rights reserved.
Andrzejewska, W; Pietralik, Z; Skupin, M; Kozak, M
2016-10-01
Dicationic (gemini) surfactants are agents that can be used for the preparation of stable complexes of nucleic acids, particularly siRNA for therapeutic purposes. In this study, we demonstrated that bis-imidazolium gemini surfactants with variable lengths of dioxyalkyl linker groups (from dioxyethyl to dioxydodecyl) and dodecyl side chains are excellent for the complexation of siRNA. All of these compounds effectively complexed siRNA in a charge ratio range (p/n) of 1.5-10. The low resolution structure of siRNA oligomers was characterised by small angle scattering of synchrotron radiation (SR-SAXS) and ab initio modelling. The structures of the formed complexes were also analysed using SR-SAXS, circular dichroism studies and electrophoretic mobility tests. The most promising agents for complexation with siRNA were the surfactants that contained dioxyethyl and dioxyhexyl spacer groups. Copyright © 2016 Elsevier B.V. All rights reserved.
Spectroscopic Validation of Low-metallicity Stars from RAVE
NASA Astrophysics Data System (ADS)
Placco, Vinicius M.; Beers, Timothy C.; Santucci, Rafael M.; Chanamé, Julio; Sepúlveda, María Paz; Coronado, Johanna; Points, Sean D.; Kaleida, Catherine C.; Rossi, Silvia; Kordopatis, Georges; Lee, Young Sun; Matijevič, Gal; Frebel, Anna; Hansen, Terese T.; Holmbeck, Erika M.; Rasmussen, Kaitlin C.; Roederer, Ian U.; Sakari, Charli M.; Whitten, Devin D.
2018-06-01
We present results from a medium-resolution (R ∼ 2000) spectroscopic follow-up campaign of 1694 bright (V < 13.5), very metal-poor star candidates from the RAdial Velocity Experiment (RAVE). Initial selection of the low-metallicity targets was based on the stellar parameters published in RAVE Data Releases 4 and 5. Follow up was accomplished with the Gemini-N and Gemini-S, the ESO/NTT, the KPNO/Mayall, and the SOAR telescopes. The wavelength coverage for most of the observed spectra allows for the determination of carbon and α-element abundances, which are crucial for considering the nature and frequency of the carbon-enhanced metal-poor (CEMP) stars in this sample. We find that 88% of the observed stars have [{Fe}/{{H}}] ≤ ‑1.0, 61% have [{Fe}/{{H}}] ≤ ‑2.0, and 3% have [{Fe}/{{H}}] ≤ ‑3.0 (with four stars at [{Fe}/{{H}}] ≤ ‑3.5). There are 306 CEMP star candidates in this sample, and we identify 169 CEMP Group I, 131 CEMP Group II, and 6 CEMP Group III stars from the A(C) versus [Fe/H] diagram. Inspection of the [α /{{C}}] abundance ratios reveals that five of the CEMP Group II stars can be classified as “mono-enriched second-generation” stars. Gaia DR1 matches were found for 734 stars, and we show that transverse velocities can be used as a confirmatory selection criteria for low-metallicity candidates. Selected stars from our validated list are being followed-up with high-resolution spectroscopy to reveal their full chemical-abundance patterns for further studies.
NASA Astrophysics Data System (ADS)
Jørgensen, Inger; Chiboucas, Kristin; Hibon, Pascale; Nielsen, Louise D.; Takamiya, Marianne
2018-04-01
The Gemini/HST Galaxy Cluster Project (GCP) covers 14 z = 0.2–1.0 clusters with X-ray luminosity of {L}500≥slant {10}44 {erg} {{{s}}}-1 in the 0.1–2.4 keV band. In this paper, we provide homogeneously calibrated X-ray luminosities, masses, and radii, and we present the complete catalog of the ground-based photometry for the GCP clusters. The clusters were observed with either Gemini North or South in three or four of the optical passbands g‧, r‧, i‧, and z‧. The photometric catalog includes consistently calibrated total magnitudes, colors, and geometrical parameters. The photometry reaches ≈25 mag in the passband closest to the rest-frame B band. We summarize comparisons of our photometry with data from the Sloan Digital Sky Survey. We describe the sample selection for our spectroscopic observations, and establish the calibrations to obtain rest-frame magnitudes and colors. Finally, we derive the color–magnitude relations for the clusters, and briefly discuss these in the context of evolution with redshift. Consistent with our results based on spectroscopic data, the color–magnitude relations support passive evolution of the red sequence galaxies. The absence of change in the slope with redshift constrains the allowable age variation along the red sequence to <0.05 dex between the brightest cluster galaxies and those four magnitudes fainter. This paper serves as the main reference for the GCP cluster and galaxy selection, X-ray data, and ground-based photometry.
Mantha, Sriteja; McDaniel, Jesse G.; Perroni, Dominic V.; ...
2016-12-27
Gemini surfactants comprise two single-tailed surfactants connected by a linker at or near the hydrophilic headgroup. They display a variety of water concentration-dependent lyotropic liquid crystal (LLC) morphologies that are sensitive to surfactant molecular structure, and na- ture of the headgroups and counterions. Recently, an interesting dependence of the aqueous phase behavior on the length of the linker has been discovered; odd-numbered linker length surfactants exhibit characteristically different phase diagrams than even-numbered linker sur- factants. In this work, we investigate this “odd/even effect” using computer simulations, focusing on experimentally studied gemini dicarboxylates with Na + counterions, 7 non-terminal carbon atomsmore » in the tails, and either 3, 4, 5, or 6 carbon atoms in the linker (denoted Na-73, Na-74, Na-75, and Na-76 respectively). We find that the relative electrostatic repulsion be- tween headgroups in the different morphologies is correlated with qualitative features of the experimental phase diagrams, predicting destabilization of hexagonal phases as the cylinders pack close together at low water content. Significant differences in the relative headgroup ori- entations of Na-74 and Na-76 compared to Na-73 and Na-75 surfactants lead to differences in linker-linker packing, and long-range headgroup/headgroup electrostatic repulsion, which affects the delicate electrostatic balance between hexagonal and gyroid phases. Finally, much of the fundamental insight presented in this work is enabled by the ability to computationally construct and analyze metastable phases that are not observable in experiments.« less
First Magnetic Field Detection on a Class I Protostar
NASA Astrophysics Data System (ADS)
Johns-Krull, Christopher M.; Greene, Thomas P.; Doppmann, Greg W.; Covey, Kevin R.
2009-08-01
Strong stellar magnetic fields are believed to truncate the inner accretion disks around young stars, redirecting the accreting material to the high latitude regions of the stellar surface. In the past few years, observations of strong stellar fields on T Tauri stars with field strengths in general agreement with the predictions of magnetospheric accretion theory have bolstered this picture. Currently, nothing is known about the magnetic field properties of younger, more embedded Class I young stellar objects. It is believed that protostars accrete much of their final mass during the Class I phase, but the physics governing this process remains poorly understood. Here, we use high-resolution near-infrared spectra obtained with NIRSPEC on Keck and with Phoenix on Gemini South to measure the magnetic field properties of the Class I protostar WL 17. We find clear signatures of a strong stellar magnetic field. Analysis of this data suggests a surface average field strength of 2.9 ± 0.43 kG on WL 17. We present our field measurements and discuss how they fit with the general model of magnetospheric accretion in young stars. Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the Science and Technology Facilities Council (United Kingdom), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), Ministério da Ciência e Tecnologia (Brazil), and SECYT (Argentina). The Phoenix data were obtained under the program: GS-2006A-C-12.
Yoshimura, Tomokazu; Bong, Miri; Matsuoka, Keisuke; Honda, Chikako; Endo, Kazutoyo
2009-11-01
Three anionic homologues of a novel partially fluorinated carboxylate-type anionic gemini surfactant, N,N'-di(3-perfluoroalkyl-2-hydroxypropyl)-N,N'-diacetic acid ethylenediamine (2C(n)(F) edda, where n represents the number of carbon atoms in the fluorocarbon chain (4, 6, and 8)) were synthesized. In these present gemini surfactants, the relatively small carboxylic acid moieties form hydrophilic head groups. The surface properties or structures of the aggregates of these surfactants are strongly influenced by the nonflexible fluorocarbons and small head groups; this is because these surfactants have a closely packed molecular structure. The equilibrium surface tension properties of these surfactants were measured at 298.2K for various fluorocarbon chain lengths. The plot of the logarithm of the critical micelle concentration (cmc) against the fluorocarbon chain lengths for 2C(n)(F) edda (n=4, 6, and 8) showed a minimum for n=6. Furthermore, the lowest surface tension of 2C(6)(F) edda at the cmc was 16.4mNm(-1). Such unique behavior has not been observed even in the other fluorinated surfactants. Changes in the shapes and sizes of these surfactant aggregate with concentration were investigated by dynamic light scattering and transmission electron microscopy (TEM). The TEM micrographs showed that in an aqueous alkali solution, 2C(n)(F) edda mainly formed aggregates with stringlike (n=4), cagelike (n=6), and distorted bilayer structures (n=8). The morphological changes in the aggregates were affected by the molecular structure composed of nonflexible fluorocarbon chains and flexible hydrocarbon chains.
Interaction effects on galaxy pairs with Gemini/GMOS- III: stellar population synthesis
NASA Astrophysics Data System (ADS)
Krabbe, A. C.; Rosa, D. A.; Pastoriza, M. G.; Hägele, G. F.; Cardaci, M. V.; Dors, O. L., Jr.; Winge, C.
2017-05-01
We present an observational study of the impacts of interactions on the stellar population in a sample of galaxy pairs. Long-slit spectra in the wavelength range 3440-7300 Å obtained with the Gemini Multi-Object Spectrograph (GMOS) at Gemini South for 15 galaxies in nine close pairs were used. The spatial distributions of the stellar population contributions were obtained using the stellar population synthesis code starlight. Taking into account the different contributions to the emitted light, we found that most of the galaxies in our sample are dominated by young/intermediate stellar populations. This result differs from the one derived for isolated galaxies, where the old stellar population dominates the disc surface brightness. We interpreted such different behaviour as being due to the effect of gas inflows along the discs of interacting galaxies on the star formation over a time-scale of the order of about 2 Gyr. We also found that, in general, the secondary galaxy of a pair has a higher contribution from the young stellar population than the primary one. We compared the estimated values of stellar and nebular extinction derived from the synthesis method and the Hα/Hβ emission-line ratio, finding that nebular extinctions are systematically higher than stellar ones by about a factor of 2. We did not find any correlation between nebular and stellar metallicities. Neither did we find a correlation between stellar metallicities and ages, while a positive correlation between nebular metallicities and stellar ages was obtained, with older regions being the most metal-rich.
Shabtay, Ayelet; Sharabani, Hagar; Barvish, Zeev; Kafka, Michael; Amichay, Doron; Levy, Joseph; Sharoni, Yoav; Uskokovic, Milan R.; Studzinski, George P.; Danilenko, Michael
2008-01-01
Objective Differentiation therapy with the hormonal form of vitamin D, 1α,25-dihydroxyvitamin D3 (1,25D3), is a promising approach to treatment of acute myeloid leukemia (AML); however, 1,25D3 induces hypercalcemia at pharmacologically active doses. We investigated the in vitro and in vivoantileukemic efficacy of combined treatment with non-toxic doses of a low-calcemic 1,25D3 analogue, 1,25-dihydroxy-21(3-hydroxy-3-methyl-butyl)-19-nor-cholecalciferol (19-nor-Gemini; Ro27-5646), and rosemary plant agents in a mouse model of AML. Methods Proliferation and differentiation of WEHI-3B D– (WEHI) murine myelomonocytic leukemia cellsin vitro were determined by standard assays. Reactive oxygen species, glutathione and protein expression levels were measured by flow cytometry, enzymatic assay and Western blotting, respectively. Systemic AML was developed by intravenous injection of WEHI cells in syngeneic Balb/c mice. Results 19-nor-Gemini had a higher potency than its parent compounds, Gemini (Ro27-2310) and 1,25D3, in the induction of differentiation (EC50 = 0.059 ± 0.011, 0.275 ± 0.093 and 0.652 ± 0.085 nM, respectively) and growth arrest (IC50 = 0.072 ± 0.018, 0.165 ± 0.061 and 0.895 ± 0.144 nM, respectively) in WEHI cells in vitro, and lower in vivo toxicity. Combined treatment of leukemia-bearing mice with 19-nor-Gemini (injected intraperitoneally) and standardized rosemary extract (mixed with food) resulted in a synergistic increase in survival (from 42.2 ± 2.5 days in untreated mice to 66.5 ± 4.2 days, n = 3) and normalization of white blood cell and differential counts. This was consistent with strong cooperative antiproliferative and differentiation effects of low concentrations of 19-nor-Gemini or 1,25D3 combined with rosemary extract or its major polyphenolic component, carnosic acid, as well as with the antioxidant action of rosemary agents and vitamin D derivatives in WEHI cell cultures. Conclusion Combined effectiveness of 1,25D3 analogues and rosemary agents against mouse AML warrants further exploration of this therapeutic approach in translational models of human leukemia. PMID:18852491
Donkuru, McDonald; Chitanda, Jackson M; Verrall, Ronald E; El-Aneed, Anas
2014-04-15
This study aimed at evaluating the collision-induced dissociation tandem mass spectrometric (CID-MS/MS) fragmentation patterns of novel β-cyclodextrin-substituted- and bis-pyridinium gemini surfactants currently being explored as nanomaterial drug delivery agents. In the β-cyclodextrin-substituted gemini surfactants, a β-cyclodextrin ring is grafted onto an N,N-bis(dimethylalkyl)-α,ω-aminoalkane-diammonium moiety using variable succinyl linkers. In contrast, the bis-pyridinium gemini surfactants are based on a 1,1'-(1,1'-(ethane-1,2-diylbis(sulfanediyl))bis(alkane-2,1-diyl))dipyridinium template, defined by two symmetrical N-alkylpyridinium parts connected through a fixed ethane dithiol spacer. Detection of the precursor ion [M](2+) species of the synthesized compounds and the determination of mass accuracies were conducted using a QqTOF-MS instrument. A multi-stage tandem MS analysis of the detected [M](2+) species was conducted using the QqQ-LIT-MS instrument. Both instruments were equipped with an electrospray ionization (ESI) source. Abundant precursor ion [M](2+) species were detected for all compounds at sub-1 ppm mass accuracies. The β-cyclodextrin-substituted compounds, fragmented via two main pathways: Pathway 1: the loss of one head-tail region produces a [M-(N(Me)2-R)](2+) ion, from which sugar moieties (Glc) are sequentially cleaved; Pathway 2: both head-tail regions are lost to give [M-2(N(Me)2-R)](+), followed by consecutive loss of Glc units. Alternatively, the cleavage of the Glc units could also have occurred simultaneously. Nevertheless, the fragmentation evolved around the quaternary ammonium cations, with characteristic cleavage of Glc moieties. For the bis-pyridinium gemini compounds, they either lost neutral pyridine(s) to give doubly charged ions (Pathway A) or formed complementary pyridinium alongside other singly charged ions (Pathway B). Similar to β-cyclodextrin-substituted compounds, the fragmentation was centered on the pyridinium functional groups. The MS(n) analyses of these novel gemini surfactants, reported here for the first time, revealed diagnostic ions for each compound, with a universal fragmentation pattern for each compound series. The diagnostic ions will be employed within liquid chromatography (LC)/MS/MS methods for screening, identification, and quantification of these compounds within biological samples. Copyright © 2014 John Wiley & Sons, Ltd.
NASA Astrophysics Data System (ADS)
Fletcher, L. N.; Orton, G. S.; Mousis, O.; de Pater, I.; Hammel, H. B.; Golisch, W.; Edwards, M.; Yanamandra-Fisher, P. A.; Fisher, B.; Greene, Z.; Lai, S.; Otto, E.; Reshetnikov, N.; Sanchez-Lavega, A.; Simon-Miller, A. A.; Hueso, R.; Perez-Hoyos, S.
2009-12-01
We present analysis of thermal-infrared imaging and spectroscopy of the impact site near the south polar region of Jupiter (see Orton et al., AGU 2009). Enhanced thermal emission was first detected on July 20 2009 in 7-25 micron imaging from the MIRSI instrument on NASA’s IRTF. These observations, just two rotations after the impact, indicated the localised, high-temperature thermal signature of the ejecta field, coincident with the location of high-altitude particulate debris observed in the near-IR and visible. The impact feature was most visible in the 9-11 micron range, suggestive of enhanced emission from hydrocarbons and ammonia gas in the lower stratosphere. Subsequent thermal imaging of the impact region reveals the radiative cooling of the impact site and the changing morphology due to the redistribution of material by Jupiter’s zonal and meridional wind field. We acquired Gemini-N/Michelle imaging on July 22, Gemini-S/TReCS imaging on July 24 and August 5 and 9, and an extensive campaign of VLT/VISIR imaging on July 24, 26 and August 5, 10, 15, 16, at which point (4 weeks after the impact) the thermal signature could no longer be reliably distinguished, even with sub-arcsecond diffraction-limited angular resolution. Tropospheric and stratospheric temperatures and aerosol opacity are derived via optimal estimation retrievals (Fletcher et al. 2009, Icarus, 200, p154). Enhancement of hydrocarbons and gaseous ammonia are determined via iterative forward modelling, aided by spectral observations obtained with the slit aligned east-west through the impact feature from Gemini-S/TReCS (July 24) and VLT/VISIR (July 26, August 12-13). Low-resolution N-band (8-13 microns) Gemini-S/TReCS spectra confirm the enhanced emission over a broad range of wavelengths; Q-band (17-25 micron) spectra are used to study upper tropospheric temperatures in the aftermath of the collision and the rate of radiative cooling. VLT/VISIR spectra provide higher spectral resolutions in narrow wavelength ranges near 8.02, 10.49, 11.31, 11.60, 12.24 and 13.36 microns, sensitive to NH3, CH4 and hydrocarbon emission features. Iterative forward modelling of these spectra will be used to deduce the unique chemical composition and the three-dimensional thermal structure of the impact site, compared with the ‘unperturbed’ atmosphere at the same latitude. * Fletcher is supported by an appointment to the NASA Postdoctoral Program at the Jet Propulsion Laboratory/California Institute of Technology, administered by Oak Ridge Associated Universities through a contract with NASA. We wish to acknowledge the invaluable contributions of the support staff at IRTF, VLT and Gemini.
GEMINI-6 - EARTH-SKY VIEW - AUSTRALIA - OUTER SPACE
1965-12-16
S65-63136 (16 Dec. 1965) --- Shark Bay area on the western coast of Western Australia as seen from the Gemini-6 spacecraft during its 16th revolution of Earth. City of Carnarven, where NASA has a tracking station, is located near the bottom of picture in lower left corner, near mouth of stream. Indian Ocean is body of water at upper right. South is toward top of picture. Photo credit: NASA or National Aeronautics and Space Administration
Radiation measurements aboard the fourth Gemini flight.
Janni, J F; Schneider, M F
1967-01-01
Two special tissue-equivalent ionization chambers and 5 highly sensitive passive dosimetry packages were flown aboard the recent Gemini 4 flight for the purpose of obtaining precise values of instantaneous dose rate, accumulated dose. and shielding effectiveness. This experiment marked the first time that well-defined tissue dose and radiation survey measurements have been carried out in manned spaceflight operations. Since all measurements were accomplished under normal spacecraft environmental conditions, the biological dose resulted primarily from trapped inner Van Allen Belt radiation encountered by the spacecraft in the South Atlantic Anomaly. The experiment determined the particle type, ionizing and penetrating power, and variation with time and position within the Gemini spacecraft. Measured dose rates ranged from 100 mrad/hr for passes penetrating deeply into the South Atlantic Anomaly to less than 0.1 mrad/hr from lower latitude cosmic radiation. The accumulated tissue dose measured by the active ionization chambers, shielded by 0.4 gm/cm2 for the 4-day mission, was 82 mrad. Since the 5 passive dosimetry packages were each located in different positions within the spacecraft, the total mission surface dose measured by these detectors varied from 73 to 27 mrad, depending upon location and shielding. The particles within the spacecraft were recorded in nuclear emulsion, which established that over 90% of the tissue dose was attributable to penetrating protons. This experiment indicates that the radiation environment under shielded conditions at Gemini altitudes was not hazardous.
Structure-delivery relationships of lysine-based gemini surfactants and their lipoplexes.
Damen, Mark; Cristóbal-Lecina, Edgar; Sanmartí, Glòria Colom; van Dongen, Stijn F M; García Rodríguez, Cristina L; Dolbnya, Igor P; Nolte, Roeland J M; Feiters, Martin C
2014-08-21
The synthesis and properties of gemini surfactants of the type (R(1)(CO)-Lys(H)-NH)2(CH2)n are reported. For a spacer length of n = 6, the hydrophobic acyl tail was varied in length (R(1) = C8, C10, C12, C14, C16, and C18) and, for R(1) = C18, the degree of unsaturation. For R(1)(CO) = oleoyl (C18:1 Z) the spacer length (n = 2-8) and the stereochemistry of the lysine building block were varied; a 'half-gemini' derivative with a single oleoyl tail and head group was also prepared. The potential of the gemini surfactants to transfer polynucleotides across a cell membrane was investigated by transfection of HeLa cells with beta-galactosidase, both in the presence and absence of the helper lipid DOPE. Oleoyl was found to be by far the best hydrophobic tail for this biological activity, whereas the effect of the lysine stereochemistry was less pronounced. The effect of an optimum spacer length (n = 6) was observed only in the absence of helper lipid. The most active surfactant, i.e. the one with oleoyl chains and n = 6, formed liposomes with sizes in the range of 60-350 nm, and its lipoplex underwent a transition from a lamellar to a hexagonal morphology upon lowering the pH from 7 to 3.
Catalogue of satellite photography of the active volcanoes of the world
NASA Technical Reports Server (NTRS)
Heiken, G.
1976-01-01
A catalogue is presented of active volcanoes as viewed from Earth-orbiting satellites. The listing was prepared of photographs, which have been screened for quality, selected from the earth resources technology satellite (ERTS) and Skylab, Apollo and Gemini spacecraft. There is photography of nearly every active volcano in the world; the photographs are particularly useful for regional studies of volcanic fields.
VizieR Online Data Catalog: NIR spectroscopy of new L and T dwarf candidates (Kellogg+, 2017)
NASA Astrophysics Data System (ADS)
Kellogg, K.; Metchev, S.; Miles-Paez, P. A.; Tannock, M. E.
2018-02-01
We implemented a photometric search for peculiar L and T dwarfs using combined optical (SDSS), near-infrared (2MASS) and mid-infrared (WISE) fluxes. In Paper I (Kellogg et al. 2015AJ....150..182K), we reported a sample of 314 objects that passed all of our selection criteria and visual verification. After refining our visual verification, our total candidate L and T dwarf list was cut to 156 objects including 104 new candidates. We obtained near-infrared spectroscopic observations of the remaining 104 objects in our survey (66 peculiarly red, 13 candidate binary, and 25 general ultra-cool dwarf candidates) using the SpeX instrument on the NASA Infrared Telescope Facility (IRTF) and the Gemini Near-Infrared Spectrograph (GNIRS) instrument on the Gemini North telescope. We obtained the majority of our follow-up observations (91 of 104) with the SpeX spectrograph on the IRTF in prism mode (0.75-2.5μm; R~75-150), between 2014 October and 2016 April. The observing sequences and instrument settings were the same as those in Paper I (Kellogg et al. 2015AJ....150..182K). Table1 gives observation epochs and SpeX instrument settings for each science target. We followed-up the remaining 13 objects in our candidate list using the Gemini Near-Infrared Spectrograph (GNIRS) on Gemini North (0.9-2.5μm). We observed these objects in queue mode between 2015 October and 2017 May. We took the observations in cross-dispersed mode with the short-blue camera with 32l/mm grating and a 1.0''*7.0'' slit, resulting in a resolution of R~500. We used a standard A-B-B-A nodding sequence along the slit to record object and sky spectra. Individual exposure times were 120s per pointing. Table2 gives Gemini/GNIRS observation epochs for each science target. (4 data files).
Integrating the GalileoScope into Successful Outreach Programming
NASA Astrophysics Data System (ADS)
Michaud, Peter D.; Slater, S.; Goldstein, J.; Harvey, J.; Garcia, A.
2010-01-01
Since 2004, the Gemini Observatory’s week-long Journey Through the Universe (JTtU) program has successfully shared the excitement of scientific research with teachers, students and the public on Hawaii’s Big Island. Based on the national JTtU program started in 1999, the Hawai‘i version reaches an average of 7,000 students annually and each year features a different theme shared with a diverse set of learners. In 2010, the theme includes the integration of the GalileoScope-produced as a keystone project for the International Year of Astronomy. In preparation, a pilot teacher workshop (held in October 2009) introduced local island teachers to the GalileoScope and a 128-page educator’s activity resource book coordinated by the University of Wyoming. Response from this initial teacher’s workshop has been strong and evaluations plus follow-up actions by participating teachers illustrate that the integration of the GalileoScope has been successful based upon this diverse sample. Integrating GalileoScopes into Chilean schools in 2010 is also underway at Gemini South. This program will solicit informal proposals from educators who wish to use the telescopes in classrooms and a Spanish version of the teacher resource book is planned. The authors conclude that integration of the GalileoScope into an existing outreach program is an effective way to keep content fresh, relevant and engaging for both educators and students. This initiative is funded by Gemini Observatory outreach program. The Gemini Observatory is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (US), the Science and Technology Facilities Council (UK), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), Ministério da Ciência e Tecnologia (Brazil), and Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina)
Investigation of a sample of carbon-enhanced metal-poor stars observed with FORS and GMOS
NASA Astrophysics Data System (ADS)
Caffau, E.; Gallagher, A. J.; Bonifacio, P.; Spite, M.; Duffau, S.; Spite, F.; Monaco, L.; Sbordone, L.
2018-06-01
Aims: Carbon-enhanced metal-poor (CEMP) stars represent a sizeable fraction of all known metal-poor stars in the Galaxy. Their formation and composition remains a significant topic of investigation within the stellar astrophysics community. Methods: We analysed a sample of low-resolution spectra of 30 dwarf stars, obtained using the visual and near UV FOcal Reducer and low dispersion Spectrograph for the Very Large Telescope (FORS/VLT) of the European Southern Observatory (ESO) and the Gemini Multi-Object Spectrographs (GMOS) at the GEMINI telescope, to derive their metallicity and carbon abundance. Results: We derived C and Ca from all spectra, and Fe and Ba from the majority of the stars. Conclusions: We have extended the population statistics of CEMP stars and have confirmed that in general, stars with a high C abundance belonging to the high C band show a high Ba-content (CEMP-s or -r/s), while stars with a normal C abundance or that are C-rich, but belong to the low C band, are normal in Ba (CEMP-no). Based on observations made with ESO Telescopes at the La Silla Paranal Observatory under programme ID 099.D-0791.Based on observations obtained at the Gemini Observatory (processed using the Gemini IRAF package), which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the National Research Council (Canada), CONICYT (Chile), Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina), and Ministério da Ciência, Tecnologia e Inovação (Brazil).Tables 1 and 2 are also available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/614/A68
The Gemini 8-Meter Telescopes Project
NASA Astrophysics Data System (ADS)
Boroson, Todd A.
1995-05-01
The Gemini 8-Meter Telescopes Project is an international partnership to build and operate two 8-meter telescopes, one on Mauna Kea, Hawaii, and one on Cerro Pachon, Chile. The telescopes will be international facilities, open to the scientific communities of the six member countries, the United States (50%), the United Kingdom (25%), Canada (15%), Chile (5%), Argentina (2.5%), and Brazil (2.5%). The telescopes are designed to exploit the best atmospheric conditions at these excellent sites. Near diffraction limited performance will be delivered at 2.2 microns and longward, with minimal degradation of the best seeing conditions at shorter wavelengths. The telescopes and facilities are designed to achieve emissivity <4% (requirement) or <2% (goal) if silver coatings are used. The instrument complement is diverse, including near- and mid-IR imagers, and near-IR and optical spectrographs. Both telescopes are equipped with f/16 articulated secondaries, and a future upgrade path to a wide-field f/6 configuration is provided. The northern telescope also includes a natural-guide-star adaptive optics system. Up to five instruments can be mounted simultaneously on the Cassegrain instrument interface. Approximately 50% of the telescope time will be flexibly scheduled, allowing most efficient utilization of the times of best conditions and facilitating programs which are difficult to schedule, such as synoptic and target-of-opportunity. First light for the Mauna Kea telescope is expected in late 1998, and for the Cerro Pachon telescope in mid-2000. This talk will report on construction progress, the instrumental capabilities, and operations strategies being considered. The Gemini 8-meter Telescopes Project is managed by the Association of Universities for Research in Astronomy (AURA), Inc. under a cooperative agreement with the National Science Foundation which serves as executive agency for the Gemini partner countries. U.S. participation in the project is through the U.S. Gemini Program, a division of the National Optical Astronomy Observatories. NOAO is operated by AURA, Inc. under cooperative agreement with the National Science Foundation.
NASA Astrophysics Data System (ADS)
Schirmer, M.; Carrasco, E. R.; Pessev, P.; Garrel, V.; Winge, C.; Neichel, B.; Vidal, F.
2015-04-01
We have observed two of the six Frontier Fields galaxy clusters, MACS J0416.1-2403 and Abell 2744, using the Gemini Multi-Conjugate Adaptive Optics System (GeMS) and the Gemini South Adaptive Optics Imager (GSAOI). With 0.″ 08-0.″ 10 FWHM our data are nearly diffraction-limited over a 100\\prime\\prime × 100\\prime\\prime wide area. GeMS/GSAOI complements the Hubble Space Telescope (HST) redwards of 1.6 μm with twice the angular resolution. We reach a 5σ depth of {{K}s}˜ 25.6 mag (AB) for compact sources. In this paper, we describe the observations, data processing, and initial public data release. We provide fully calibrated, co-added images matching the native GSAOI pixel scale as well as the larger plate scales of the HST release, adding to the legacy value of the Frontier Fields. Our work demonstrates that even for fields at high galactic latitude where natural guide stars are rare, current multi-conjugated adaptive optics technology at 8 m telescopes has opened a new window on the distant universe. Observations of a third Frontier Field, Abell 370, are planned. Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the Science and Technology Facilities Council (United Kingdom), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), Ministério da Ciência, Tecnologia e Inovação (Brazil) and Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina). Based on observations made with ESO Telescopes at the La Silla and Paranal Observatories, Chile.
Spectroscopy of Giant Arcs Behind the Strongest Lenses in the Universe
NASA Astrophysics Data System (ADS)
Hennawi, Joseph F.; Gladders, Michael; Oguri, Masamune; Koester, Benjamin; Bayliss, Matt; Dahle, Hakon; Natarajan, Priya
2009-02-01
We have conducted a deep ((mu)_g ≲ 24) imaging survey using the WIYN 4-m telescope, the UH 88-inch telescope, and the 2.5m Nordic Optical Telescope (NOT) to search for giant arcs behind the richest clusters identified in the Gpc^3 volume of the SDSS. By imaging nearly 500 massive clusters, this ongoing survey has uncovered some of the most dramatic examples of gravitational lensing ever discovered, similar to `poster-children' like Abell 1689 and CL0024+1654. We propose to use GMOS on Gemini-North and the Blue Channel Spectrograph on the MMT to determine arc redshifts in these new lenses. When combined with our GMOS data from a similar program in 2008A, this proposal will result in a sample of 60 gravitationally lensed galaxies behind ~ 25 clusters. These arc redshifts pinpoint the mass of dark matter interior to the Einstein radius in the cluster core (R < 200 kpc; comoving). The larger scale (R ~ 1-5 Mpc) weak lensing shear has been measured for more than half of our targets from deep imaging at NOT, WIYN, Subaru, and using archival data from HST. GMOS arc redshifts combined with weak and strong lensing will allow us to measure the density profile of dark matter halos on scales 200 kpc < R < 5 Mpc for the statistical sample of lensing clusters, providing a powerful test of the (Lambda)CDM paradigm.
GEMINI-TITAN (GT)-11 - EARTH - SKY - DOCKING - OUTER SPACE
1966-07-18
S66-46144 (18 July 1966) --- The Gemini-10 spacecraft is successfully docked with the Agena Target Docking Vehicle 5005. The Agena display panel is clearly visible. After docking with the Agena, astronauts John W. Young, command pilot, and Michael Collins, pilot, fired the 16,000-pound thrust engine of Agena-10's primary propulsion system to boost the combined vehicles into an orbit with an apogee of 413 nautical miles to set a new altitude record for manned spaceflight. Photo credit: NASA
Optical Performance Of The Gemini Carbon Dioxide Laser Fusion System
NASA Astrophysics Data System (ADS)
Viswanathan, V. K.; Hayden, J. J.; Liberman, I.
1980-11-01
The performance of the Gemini two beam carbon dioxide laser fusion system was recently upgraded by installation of optical components with improved quality in the final amplifier. A theoretical analysis was conducted in conlunction with measurements of the new performance. The analysis and experimental procedures, and results obtained are reported and compared. Good agreement was found which was within the uncertainties of the analysis and the inaccuracies of the experiments. The focal spot Strehl ratio was between 0.24 and 0.3 for both beams.
Arabian Peninsula and northeast Africa as seen from Gemini 11 spacecraft
NASA Technical Reports Server (NTRS)
1966-01-01
Arabian Peninsula (on left) and northeast Africa (on right) as seen from the Gemini 11 spacecraft at an altitude of 340 nautical miles during its 27th revolution of the earth, looking southeast. Saudia Arabia, South Arabia, Yemen and Aden Protectorate are at left. At bottom right is Ethiopia. French Somaliland is in center on right shore. Somali is at upper right. Body of water at bottom is Red Sea. Gulf of Aden is in center; and at top left is Indian Ocean.
Mapping the Physical and Chemical Conditions of the Ring Nebula
NASA Astrophysics Data System (ADS)
Leal-Ferreira, Marcelo L.; Aleman, Isabel; Gaughan, Andrea; Ladjal, Djazia; Ueta, Toshiya; Kerber, Samuel; Conn, Blair; Gardiner, Rhiannon; Tielens, Alexander G. G. M.
2017-10-01
We observed the Planetary Nebula NGC 6720 with the Gemini Telescope and the Gemini Multi-Object Spectrographs. We obtained spatial maps of 36 emission-lines in the wavelength range between 3600 Å and 9400 Å. We derived maps of c(Hβ), electronic densities, electronic temperatures, ionic and elemental abundances, and Ionization Correction Factors (ICFs) in the source and investigated the mass-loss history of the progenitor. The elemental abundance results indicate the need for ICFs based on three-dimensional photoionization models.
Astronaut Thomas P. Stafford - Training - Parasail - Gemini-Titan (GT)-5 Pilot - Galveston Bay, TX
1965-08-23
S65-51948 (23 Aug. 1965) --- Astronaut Thomas P. Stafford, Gemini-6 prime crew pilot, stands ready to take part in parasail training in Galveston Bay, Texas. Wearing spacesuit, helmet and carrying water survival gear, he will be lifted into the air by a deployed parachute and guided over the Bay where he will drop into the water to test airdrop and water survival techniques. Photo credit: NASA or National Aeronautics and Space Administration
GEMINI-TITAN (GT-11) - EARTH SKY - OUTER SPACE
1966-09-14
S66-54677 (14 Sept. 1966) --- India and Ceylon as seen from the orbiting Gemini-11 spacecraft at an altitude of 410 nautical miles during its 26th revolution of Earth. The Indian Ocean is at bottom of picture; at left center is Arabian Sea; and at upper right is Bay of Bengal. The Maldives Islands are near nose of spacecraft. Taken with a modified 70mm Hasselblad camera, using Eastman Kodak, Ektachrome, MS. (S.O. 368) color film. Photo credit: NASA
Heroes and Legends Ribbon Cutting Ceremony
2016-11-11
Former CNN space correspondent John Zarrella, left, interviews Gemini and Apollo astronauts Jim Lovell, center and Tom Stafford during opening ceremonies for the Heroes and Legends attraction at the Kennedy Space Center Visitor Complex. The new facility includes the U.S. Astronaut Hall of Fame and looks back to the pioneering efforts of Mercury, Gemini and Apollo. It sets the stage by providing the background and context for space exploration and the legendary men and women who pioneered the nation's journey into space.
GT-6 PREFLIGHT ACTIVITY (LEAVE SUITING TRAILER) - ASTRONAUT WALTER M. SCHIRRA, JR. - SUIT
1965-12-15
S65-59974 (15 Dec. 1965) --- Astronauts Walter M. Schirra Jr. (leading), command pilot; and Thomas P. Stafford, pilot, leave the suiting trailer at Launch Complex 16 during the Gemini-6 prelaunch countdown at Cape Kennedy, Florida. They entered a special transport van which carried them to Pad 19 and their spacecraft. Gemini-6 lifted off at 8:37 a.m. (EST) on Dec. 15, 1965. Photo credit: NASA or National Aeronautics and Space Administration
NASA Technical Reports Server (NTRS)
Marmolejo, Jose; Ewert, Michael
2016-01-01
The Engineering Directorate at the NASA - Johnson Space Center is outfitting a 20-Foot diameter hypobaric chamber in Building 7 to support future deep-space Environmental Control & Life Support System (ECLSS) research as part of the Human Exploration System Test-bed for Integration and Advancement (HESTIA) Project. This human-rated chamber is the only NASA facility that has the unique experience, chamber geometry, infrastructure, and support systems capable of conducting this research. The chamber was used to support Gemini, Apollo, and SkyLab Missions. More recently, it was used to conduct 30-, 60-, and 90-day human ECLSS closed-loop testing in the 1990s to support the International Space Station and life support technology development. NASA studies show that both planetary surface and deep-space transit crew habitats will be 3-4 story cylindrical structures driven by human occupancy volumetric needs and launch vehicle constraints. The HESTIA facility offers a 3-story, 20-foot diameter habitat consistent with the studies' recommendations. HESTIA operations follow stringent processes by a certified test team that including human testing. Project management, analysis, design, acquisition, fabrication, assembly and certification of facility build-ups are available to support this research. HESTIA offers close proximity to key stakeholders including astronauts, Human Research Program (who direct space human research for the agency), Mission Operations, Safety & Mission Assurance, and Engineering Directorate. The HESTIA chamber can operate at reduced pressure and elevated oxygen environments including those proposed for deep-space exploration. Data acquisition, power, fluids and other facility resources are available to support a wide range of research. Recently completed HESTIA research consisted of unmanned testing of ECLSS technologies. Eventually, the HESTIA research will include humans for extended durations at reduced pressure and elevated oxygen to demonstrate very high reliability of critical ECLSS and other technologies.
Molecular Gas Content of an Extremely Star-forming Herschel Observed Lensed Dusty Galaxy at z=2.685
NASA Astrophysics Data System (ADS)
Nayyeri, Hooshang; Cooray, Asantha R.; H-ATLAS
2017-01-01
We present the results of combined deep near-infrared, far infrared and millimeter observations of an extremely star forming lensed dusty star-forming galaxy (DSFG) identified from the Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS). The high redshift DSFG is gravitationally lensed by a massive WISE identified cluster at z~1 (spectroscopically confirmed with Keck/DEIMOS and Gemini/GMOS) producing multiply lensed images and arcs observed in the optical. The DSFG is spectroscopically confirmed at z=2.685 from CO(1-0) observations by GBT and separately from CO(3-2) observations by CARMA. We use the combined spectroscopic and imaging observations to construct a detailed lens model of the background DSFG which allowed us to study the sources plane properties of the target. Multi-band data from Keck/NIRC2, HST/WFC3 and Herschel yields star formation rate and stellar mass well above the main sequence. Observations of the dust continuum by the Sub-millimeter Array yields an observed total ISM mass of 6.5E+11 M* which is responsible for the intense observed star formation rates. Comparing the measured SFR with molecular gas measurements from CO(1-0) observations reveals that this system has relatively short gas depletion time scale which is consistent with the starburst phase observed in high redshift sub-millimeter galaxies.
GRACES, the Gemini remote access CFHT ESPaDOnS spectrograph: initial design and testing
NASA Astrophysics Data System (ADS)
Tollestrup, Eric V.; Pazder, John; Barrick, Gregory; Martioli, Eder; Schiavon, Ricardo; Anthony, André; Halman, Mark; Veillet, Christian
2012-09-01
The Gemini Remote Access CFHT ESPaDOnS Spectrograph (GRACES) is an innovative instrumentation experiment that will demonstrate if ESPaDOnS, a bench-mounted high-resolution optical spectrograph at CFHT, can be fed by a 270-m long fiber from the Gemini-North telescope with low enough losses to remain competitive with conventional spectrographs on other 8 to 10-m telescopes. Detailed simulations have shown that GRACES should be more sensitive than the HIRES spectrograph at Keck Observatory at wavelengths longer than about 600-700 nm. This result is possible by using FPB-type of optical fibers made by Polymicro Technologies and by keeping the critical focal ratio degradation (FRD) losses to less than 10%. Laboratory tests on these FPB optical fibers are underway and show that for 36-m lengths that the FRD losses are as low as 0.8% with a repeatability of 1%. Tests are currently underway on 280-m lengths.
GEMINI-TITAN (GT)-9- TRAINING - AEROSPACE FLIGHT SIMULATOR - PILOT - TX
1966-03-01
S66-27990 (March 1966) --- Astronaut Eugene A. Cernan, pilot for the Gemini-9 spaceflight, works out procedures for his historic space excursion in a unique manned Aerospace Flight Simulator at LTV Corp. at Dallas, Texas. The LTV simulator is used frequently by NASA astronauts for a variety of space programs maneuvers to provide many of the sensations and visual scenes of actual spaceflight. Controlled through a complex of computers, the device makes it possible for the astronauts to work out procedures, solve problems and simulate missions in real time with great accuracy. The astronaut rides in a spacecraft-like gondola which moves in roll, pitch and yaw in response to his controls and accurate computer inputs. The simulator's usual spacecraft displays and canopy have been removed and AMU backpack complete with control electronics installed. The astronaut makes his simulated flight in an inflated pressure suit and with the NASA-developed Extravehicular Life Support system chest pack which will be used in the Gemini flight. Photo credit: NASA
El Proyecto Gémini: informe actualizado y técnica de observación
NASA Astrophysics Data System (ADS)
Sahade, J.; Lapasset, E.; Levato, H.
Se describirá la situación actual en lo que se refiere al desarrollo del Proyecto Gémini en cuanto a su estructura, faz constructiva y programación general. Se informará sobre los planes a desarrollar en el tiempo de verificación científica y puesta a punto del instrumental, a partir de la primera imagen que se obtenga con el telescopio Gemini Norte. Se presentará, además, el plan operativo para observar con los telescopios Gemini tal cual está concebido hasta la fecha, describiéndose el proceso desde el mismo momento en que un investigador decide presentar una propuesta para observar con uno de los telescopios, hasta el archivo y derechos de propiedad sobre los datos. Se decribe también el ``soft" denominado Observing Tool (OT) que es clave en la planificación científica de Gemini y que puede ser utilizado ``off-line" en cualquier PC con un entorno windows.
ASTRONAUT WHITE, EDWARD H. II - GEMINI-IV - EXTRAVEHICULAR ACTIVITY (EVA) - CREW TRAINING - MSC
2009-06-03
S65-30431 (3 June 1965) --- Astronaut Edward H. White II, pilot of the Gemini IV four-day Earth-orbital mission, floats in the zero gravity of space outside the Gemini IV spacecraft. Behind him is the brilliant blue Earth and its white cloud cover. White wears a specially designed spacesuit; and the visor of the helmet is gold plated to protect him against the unfiltered rays of the sun. He wears an emergency oxygen pack, also. He is secured to the spacecraft by a 25-feet umbilical line and a 23-feet tether line, both wrapped in gold tape to form one cord. In his left hand is a Hand-Held Self-Maneuvering Unit (HHSMU) with which he controls his movements in space. Astronaut James A. McDivitt, command pilot of the mission, remained inside the spacecraft. Photo credit: NASA EDITOR'S NOTE: Astronaut White died in the Apollo/Saturn 204 fire at Cape Kennedy on Jan. 27, 1967.
Small angle neutron scattering study of the gemini nonionic surfactant in heavy water solutions
NASA Astrophysics Data System (ADS)
Rajewska, A.
2012-03-01
The nonionic gemini surfactant α α'-[2,4,7,9-tetramethyl-5-decyne-4,7diyl]bis[ω hydroxyl-polyoxyethylene] (S-10) was investigated in heavy water solutions only for concentrations: 2.3%, 2.5%,3%, 3.4%, 4% and 5% at temperature 25°C with small angle neutron scattering (SANS) method. All of surfactants solutions were prepared using D2O (99.9% deuterated, Prikladnaia Chimia, St. Petersburg, Russia) as a solvent. The nonionic gemini surfactant S-10 was obtained from Air Products & Chemicals, Inc., and used without further purification. All SANS measurements were performed on V-4 SANS spectrometer at BENSC, Berlin (Germany). Neutrons were used in wavelength range of 0.02 - 4 nm-1. For the measurements quartz cells of were used during experiment. Up to 14 such cells were placed in a holder. Results from experiment was calculated and evaluated with PCG 2.0 program from Graz University (Austria). In the investigated solutions two axis ellipsoidal micelles was observed.
Experiment S001: Zodiacal Light Photography
NASA Technical Reports Server (NTRS)
Ney, E. P.; Huch, W. F.
1971-01-01
Observations made during the Gemini 5, 9, and 10 missions in the context of their relation to ground-based and balloon-based experiments on dim-light phenomena are reported. Zodiacal light is the visible manifestation of dust grains in orbit around the sun. The negatives that were exposed on the Gemini 9 mission were studied by the use of an isodensitracer to produce intensity isophotes. Data on the following factors were obtained: (1) intensity distribution of the zodiacal light, both morning and evening; (2) the height and intensity of the airglow at various geographic positions; and (3) intensity distribution of the Milky Way in the region of the sky near Cygnus. Also, a previously unreported phenomenon was discovered. This phenomenon appeared as an upward extension of the normal 90-kilometer airglow layer. The extension was in the form of wisps or plumes approximately 5 deg wide and extending upward approximately 5 deg. The results obtained from pictures exposed on the Gemini 10 mission were of qualitative or geometrical value only.
OCTOCAM: A Workhorse Instrument for the Gemini Telescopes During the Era of LSST
NASA Astrophysics Data System (ADS)
Roming, Peter; van der Horst, Alexander; OCTOCAM Team
2018-01-01
The decade of the 2020s are planned to be an era of large surveys and giant telescopes. A trademark of this era will be the large number of interesting objects observed daily by high-cadence surveys, such as the LSST. Because of the sheer numbers, only a very small fraction of these interesting objects will be observed with extremely large telescopes. The follow up workhorses during this era will be the 8-meter class telescopes and corresponding instruments that are prepared to pursue these interesting objects. One such workhorse instrument is OCTOCAM, a highly efficient instrument designed to probe the time domain window with simulatenous broad-wavelength coverage. OCTOCAM optimizes the use of Gemini for broadband imaging and spectroscopic single-target observations. The instrument is designed for high temporal resolution, broad spectral coverage, and moderate spectral resolution. OCTOCAM was selected as part of the Gemini instrumentation program in early 2017. Here we provide a description of the science cases to be addressed, overall instrument design, and current status.
Speckle Imaging at Gemini and the DCT
NASA Astrophysics Data System (ADS)
Horch, E. P.; Löbb, J.; Howell, S. B.; van Altena, W. F.; Henry, T. J.; van Belle, G. T.
2018-01-01
A program of speckle observations at Lowell Observatory's Discovery Channel Telescope (DCT) and the Gemini North and South Telescopes will be described. It has featured the Differential Speckle Survey Instrument (DSSI), built at Southern Connecticut State University in 2008. DSSI is a dual-port system that records speckle images in two colors simultaneously and produces diffraction limited images to V˜ 16.5 mag at Gemini and V˜ 14.5 mag at the DCT. Of the several science projects that are being pursued at these telescopes, three will be highlighted here. The first is high-resolution follow-up observations for Kepler and K2 exoplanet missions, the second is a study of metal-poor spectroscopic binaries in an attempt to resolve these systems and determine their visual orbits en route to making mass determinations, and the third is a systematic survey of nearby late-type dwarfs, where the multiplicity fraction will be directly measured and compared to that of G dwarfs. The current status of these projects is discussed and some representative results are given.
Identification of old tidal dwarfs near early-type galaxies from deep imaging and H I observations
NASA Astrophysics Data System (ADS)
Duc, Pierre-Alain; Paudel, Sanjaya; McDermid, Richard M.; Cuillandre, Jean-Charles; Serra, Paolo; Bournaud, Frédéric; Cappellari, Michele; Emsellem, Eric
2014-05-01
It has recently been proposed that the dwarf spheroidal galaxies located in the Local Group discs of satellites (DoSs) may be tidal dwarf galaxies (TDGs) born in a major merger at least 5 Gyr ago. Whether TDGs can live that long is still poorly constrained by observations. As part of deep optical and H I surveys with the Canada-France-Hawaii Telescope (CFHT) MegaCam camera and Westerbork Synthesis Radio Telescope made within the ATLAS3D project, and follow-up spectroscopic observations with the Gemini-North telescope, we have discovered old TDG candidates around several early-type galaxies. At least one of them has an oxygen abundance close to solar, as expected for a tidal origin. This confirmed pre-enriched object is located within the gigantic, but very low surface brightness, tidal tail that emanates from the elliptical galaxy, NGC 5557. An age of 4 Gyr estimated from its SED fitting makes it the oldest securely identified TDG ever found so far. We investigated the structural and gaseous properties of the TDG and of a companion located in the same collisional debris, and thus most likely of tidal origin as well. Despite several Gyr of evolution close to their parent galaxies, they kept a large gas reservoir. Their central surface brightness is low and their effective radius much larger than that of typical dwarf galaxies of the same mass. This possibly provides us with criteria to identify tidal objects which can be more easily checked than the traditional ones requiring deep spectroscopic observations. In view of the above, we discuss the survival time of TDGs and question the tidal origin of the DoSs.
Fuel Cell Research and Development for Future NASA Missions
NASA Technical Reports Server (NTRS)
Manzo, Michelle A.; Hoberecht, Mark; Loyselle, Patricia; Burke, Kenneth; Bents, David; Farmer, Serene; Kohout, Lisa
2006-01-01
NASA has been using fuel cell systems since the early days of space flight. Polymer Exchange Membrane Fuel cells provided the primary power for the Gemini and Apollo missions and more recently, alkaline fuel cells serve as the primary power source for the Space Shuttle. NASA's current investments in fuel cell technology support both Exploration and Aeronautics programs. This presentation provides an overview of NASA's fuel cell development programs.
PEERING INTO THE GIANT-PLANET-FORMING REGION OF THE TW HYDRAE DISK WITH THE GEMINI PLANET IMAGER
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rapson, Valerie A.; Kastner, Joel H.; Millar-Blanchaer, Maxwell A.
2015-12-20
We present Gemini Planet Imager (GPI) adaptive optics near-infrared images of the giant-planet-forming regions of the protoplanetary disk orbiting the nearby (D = 54 pc), pre-main-sequence (classical T Tauri) star TW Hydrae. The GPI images, which were obtained in coronagraphic/polarimetric mode, exploit starlight scattered off small dust grains to elucidate the surface density structure of the TW Hya disk from ∼80 AU to within ∼10 AU of the star at ∼1.5 AU resolution. The GPI polarized intensity images unambiguously confirm the presence of a gap in the radial surface brightness distribution of the inner disk. The gap is centered near ∼23 AU,more » with a width of ∼5 AU and a depth of ∼50%. In the context of recent simulations of giant-planet formation in gaseous, dusty disks orbiting pre-main-sequence stars, these results indicate that at least one young planet with a mass ∼0.2 M{sub J} could be present in the TW Hya disk at an orbital semimajor axis similar to that of Uranus. If this (proto)planet is actively accreting gas from the disk, it may be readily detectable by GPI or a similarly sensitive, high-resolution infrared imaging system.« less
SPT-GMOS: A GEMINI/GMOS-SOUTH SPECTROSCOPIC SURVEY OF GALAXY CLUSTERS IN THE SPT-SZ SURVEY
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bayliss, M. B.; Ruel, J.; Stubbs, C. W.
We present the results of SPT-GMOS, a spectroscopic survey with the Gemini Multi-Object Spectrograph (GMOS) on Gemini South. The targets of SPT-GMOS are galaxy clusters identified in the SPT-SZ survey, a millimeter-wave survey of 2500 deg{sup 2} of the southern sky using the South Pole Telescope (SPT). Multi-object spectroscopic observations of 62 SPT-selected galaxy clusters were performed between 2011 January and 2015 December, yielding spectra with radial velocity measurements for 2595 sources. We identify 2243 of these sources as galaxies, and 352 as stars. Of the galaxies, we identify 1579 as members of SPT-SZ galaxy clusters. The primary goal ofmore » these observations was to obtain spectra of cluster member galaxies to estimate cluster redshifts and velocity dispersions. We describe the full spectroscopic data set and resulting data products, including galaxy redshifts, cluster redshifts, and velocity dispersions, and measurements of several well-known spectral indices for each galaxy: the equivalent width, W , of [O ii] λλ 3727, 3729 and H- δ , and the 4000 Å break strength, D4000. We use the spectral indices to classify galaxies by spectral type (i.e., passive, post-starburst, star-forming), and we match the spectra against photometric catalogs to characterize spectroscopically observed cluster members as a function of brightness (relative to m {sup ⋆}). Finally, we report several new measurements of redshifts for ten bright, strongly lensed background galaxies in the cores of eight galaxy clusters. Combining the SPT-GMOS data set with previous spectroscopic follow-up of SPT-SZ galaxy clusters results in spectroscopic measurements for >100 clusters, or ∼20% of the full SPT-SZ sample.« less
SPT-GMOS: A Gemini/GMOS-South Spectroscopic survey of galaxy clusters in the SPT-SZ survey
Bayliss, M. B.; Ruel, J.; Stubbs, C. W.; ...
2016-11-01
Here, we present the results of SPT-GMOS, a spectroscopic survey with the Gemini Multi-Object Spectrograph (GMOS) on Gemini South. The targets of SPT-GMOS are galaxy clusters identified in the SPT-SZ survey, a millimeter-wave survey of 2500 deg 2 of the southern sky using the South Pole Telescope (SPT). Multi-object spectroscopic observations of 62 SPT-selected galaxy clusters were performed between 2011 January and 2015 December, yielding spectra with radial velocity measurements for 2595 sources. We identify 2243 of these sources as galaxies, and 352 as stars. Of the galaxies, we identify 1579 as members of SPT-SZ galaxy clusters. The primary goalmore » of these observations was to obtain spectra of cluster member galaxies to estimate cluster redshifts and velocity dispersions. We describe the full spectroscopic data set and resulting data products, including galaxy redshifts, cluster redshifts, and velocity dispersions, and measurements of several well-known spectral indices for each galaxy: the equivalent width, W, of [O II] λλ3727, 3729 and H-δ, and the 4000 Å break strength, D4000. We use the spectral indices to classify galaxies by spectral type (i.e., passive, post-starburst, star-forming), and we match the spectra against photometric catalogs to characterize spectroscopically observed cluster members as a function of brightness (relative to m*). Lastly, we report several new measurements of redshifts for ten bright, strongly lensed background galaxies in the cores of eight galaxy clusters. Combining the SPT-GMOS data set with previous spectroscopic follow-up of SPT-SZ galaxy clusters results in spectroscopic measurements for >100 clusters, or ~20% of the full SPT-SZ sample.« less
SPT-GMOS: A Gemini/GMOS-South Spectroscopic survey of galaxy clusters in the SPT-SZ survey
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bayliss, M. B.; Ruel, J.; Stubbs, C. W.
Here, we present the results of SPT-GMOS, a spectroscopic survey with the Gemini Multi-Object Spectrograph (GMOS) on Gemini South. The targets of SPT-GMOS are galaxy clusters identified in the SPT-SZ survey, a millimeter-wave survey of 2500 deg 2 of the southern sky using the South Pole Telescope (SPT). Multi-object spectroscopic observations of 62 SPT-selected galaxy clusters were performed between 2011 January and 2015 December, yielding spectra with radial velocity measurements for 2595 sources. We identify 2243 of these sources as galaxies, and 352 as stars. Of the galaxies, we identify 1579 as members of SPT-SZ galaxy clusters. The primary goalmore » of these observations was to obtain spectra of cluster member galaxies to estimate cluster redshifts and velocity dispersions. We describe the full spectroscopic data set and resulting data products, including galaxy redshifts, cluster redshifts, and velocity dispersions, and measurements of several well-known spectral indices for each galaxy: the equivalent width, W, of [O II] λλ3727, 3729 and H-δ, and the 4000 Å break strength, D4000. We use the spectral indices to classify galaxies by spectral type (i.e., passive, post-starburst, star-forming), and we match the spectra against photometric catalogs to characterize spectroscopically observed cluster members as a function of brightness (relative to m*). Lastly, we report several new measurements of redshifts for ten bright, strongly lensed background galaxies in the cores of eight galaxy clusters. Combining the SPT-GMOS data set with previous spectroscopic follow-up of SPT-SZ galaxy clusters results in spectroscopic measurements for >100 clusters, or ~20% of the full SPT-SZ sample.« less
The Three-Dimensional Structure of HH 32 from GMOS IFU Spectroscopy
NASA Astrophysics Data System (ADS)
Beck, Tracy L.; Riera, A.; Raga, A. C.; Aspin, C.
2004-01-01
We present new high-resolution spectroscopic observations of the Herbig-Haro object HH 32 from system verification observations made with the GMOS IFU at Gemini North Observatory. The three-dimensional spectral data cover a 8.7"×5.85" spatial field and 4820-7040 Å spectral region centered on the HH 32 A knot complex. We show the position-dependent line profiles and radial velocity channel maps of the Hα line, as well as line ratio velocity channel maps of [O III] λ5007/Hα, [O I] λ6300/Hα, [N II] λ6583/Hα, [S II] λλ(6716+6730)/Hα, and [S II] λ6716/λ6730. We find that the line emission and the line ratios vary significantly on spatial scales of ~1" and over velocities of ~50 km s-1. A ``3/2-dimensional'' bow shock model is qualitatively successful at reproducing the general features of the radial velocity channel maps, but it does not show the same complexity as the data, and it fails to reproduce the line ratios in our high spatial resolution maps. The observations of HH 32 A show two or three superposed bow shocks with separations of ~3", which we interpret as evidence of a line-of-sight superposition of two or three working surfaces located along the redshifted body of the HH 32 outflow. Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the National Science Foundation on behalf of the Gemini partnership: the NSF, the Particle Physics and Astronomy Research Council (United Kingdom), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), CNPq (Brazil), and CONICET (Argentina).
Lens Model and Time Delay Predictions for the Sextuply Lensed Quasar SDSS J2222+2745*
NASA Technical Reports Server (NTRS)
Sharon, Keren; Bayliss, Matthew B.; Dahle, Hakon; Florian, Michael K.; Gladders, Michael D.; Johnson, Traci L.; Paterno-Mahler, Rachel; Rigby, Jane R.; Whitaker, Katherine E.; Wuyts, Eva
2017-01-01
SDSS J2222+2745 is a galaxy cluster at z = 0.49, strongly lensing a quasar at z = 2.805 into six widely separated images. In recent Hubble Space Telescope imaging of the field, we identify additional multiply lensed galaxies and confirm the sixth quasar image that was identified by Dahle et al. We used the Gemini-North telescope to measure a spectroscopic redshift of z = 4.56 of one of the lensed galaxies. These data are used to refine the lens model of SDSS J2222+2745, compute the time delay and magnifications of the lensed quasar images, and reconstruct the source image of the quasar host and a lensed galaxy at z = 2.3. This galaxy also appears in absorption in our Gemini spectra of the lensed quasar, at a projected distance of 34 kpc. Our model is in agreement with the recent time delay measurements of Dahle et al., who found T(sub AB) = 47.7 +/- 6.0 days and T(sub AC) = 722 +/- 24 days. We use the observed time delays to further constrain the model, and find that the model-predicted time delays of the three faint images of the quasar are T(sub AD) = 502+/- 68 days, T( sub AE) = 611 +/- 75 days, and T(sub AF) = 415 +/- 72 days. We have initiated a follow-up campaign to measure these time delays with Gemini North. Finally, we present initial results from an X-ray monitoring program with Swift, indicating the presence of hard X-ray emission from the lensed quasar, as well as extended X-ray emission from the cluster itself, which is consistent with the lensing mass measurement and the cluster velocity dispersion.
LENS MODEL AND TIME DELAY PREDICTIONS FOR THE SEXTUPLY LENSED QUASAR SDSS J2222+2745
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sharon, Keren; Johnson, Traci L.; Paterno-Mahler, Rachel
2017-01-20
SDSS J2222+2745 is a galaxy cluster at z = 0.49, strongly lensing a quasar at z = 2.805 into six widely separated images. In recent Hubble Space Telescope imaging of the field, we identify additional multiply lensed galaxies and confirm the sixth quasar image that was identified by Dahle et al. We used the Gemini-North telescope to measure a spectroscopic redshift of z = 4.56 of one of the lensed galaxies. These data are used to refine the lens model of SDSS J2222+2745, compute the time delay and magnifications of the lensed quasar images, and reconstruct the source image ofmore » the quasar host and a lensed galaxy at z = 2.3. This galaxy also appears in absorption in our Gemini spectra of the lensed quasar, at a projected distance of 34 kpc. Our model is in agreement with the recent time delay measurements of Dahle et al., who found τ {sub AB} = 47.7 ± 6.0 days and τ {sub AC} = −722 ± 24 days. We use the observed time delays to further constrain the model, and find that the model-predicted time delays of the three faint images of the quasar are τ {sub AD} = 502 ± 68 days, τ {sub AE} = 611 ± 75 days, and τ {sub AF} = 415 ± 72 days. We have initiated a follow-up campaign to measure these time delays with Gemini North. Finally, we present initial results from an X-ray monitoring program with Swift , indicating the presence of hard X-ray emission from the lensed quasar, as well as extended X-ray emission from the cluster itself, which is consistent with the lensing mass measurement and the cluster velocity dispersion.« less
Gemini/GMOS Spectroscopy of Globular Clusters in the Merger Remnant Galaxy M85
NASA Astrophysics Data System (ADS)
Ko, Youkyung; Lee, Myung Gyoon; Park, Hong Soo; Sohn, Jubee; Lim, Sungsoon; Hwang, Narae
2018-06-01
M85 is a peculiar S0 galaxy in Virgo and a well-known merger remnant. We present the first spectroscopic study of globular clusters (GCs) in M85. We obtain spectra for 21 GC candidates and the nucleus of M85 using the Gemini Multi-Object Spectrograph on the Gemini North 8.1 m telescope. From their radial velocities, 20 of the GCs are found to be members of M85. We find a strong rotation signal of the M85 GC system with a rotation amplitude of 235 km s‑1. The rotation axis of the GC system has a position angle of about 161°, which is 51.°5 larger than that of the stellar light. The rotation-corrected radial velocity dispersion of the GC system is estimated to be {σ }{{r},{cor}}=160 km s‑1. The rotation parameter {{Ω }}{R}icor}/{σ }{{r},{cor}} of the GC system is derived to be {1.47}-0.48+1.05, which is one of the largest among known early-type galaxies. The ages and metallicities of the GCs, which show the same trend as the results based on Lick indices, are derived from full spectrum fitting (ULySS). About half of the GCs are an intermediate-age population whose mean age is ∼3.7 ± 1.9 Gyr, having a mean [Fe/H] value of ‑0.26. The other half are old and metal-poor. These results suggest that M85 experienced a wet merging event about 4 Gyr ago, forming a significant population of star clusters. The strong rotational feature of the GC system can be explained by an off-center major merging.
SPT-GMOS: A Gemini/GMOS-South Spectroscopic Survey of Galaxy Clusters in the SPT-SZ Survey
NASA Astrophysics Data System (ADS)
Bayliss, M. B.; Ruel, J.; Stubbs, C. W.; Allen, S. W.; Applegate, D. E.; Ashby, M. L. N.; Bautz, M.; Benson, B. A.; Bleem, L. E.; Bocquet, S.; Brodwin, M.; Capasso, R.; Carlstrom, J. E.; Chang, C. L.; Chiu, I.; Cho, H.-M.; Clocchiatti, A.; Crawford, T. M.; Crites, A. T.; de Haan, T.; Desai, S.; Dietrich, J. P.; Dobbs, M. A.; Doucouliagos, A. N.; Foley, R. J.; Forman, W. R.; Garmire, G. P.; George, E. M.; Gladders, M. D.; Gonzalez, A. H.; Gupta, N.; Halverson, N. W.; Hlavacek-Larrondo, J.; Hoekstra, H.; Holder, G. P.; Holzapfel, W. L.; Hou, Z.; Hrubes, J. D.; Huang, N.; Jones, C.; Keisler, R.; Knox, L.; Lee, A. T.; Leitch, E. M.; von der Linden, A.; Luong-Van, D.; Mantz, A.; Marrone, D. P.; McDonald, M.; McMahon, J. J.; Meyer, S. S.; Mocanu, L. M.; Mohr, J. J.; Murray, S. S.; Padin, S.; Pryke, C.; Rapetti, D.; Reichardt, C. L.; Rest, A.; Ruhl, J. E.; Saliwanchik, B. R.; Saro, A.; Sayre, J. T.; Schaffer, K. K.; Schrabback, T.; Shirokoff, E.; Song, J.; Spieler, H. G.; Stalder, B.; Stanford, S. A.; Staniszewski, Z.; Stark, A. A.; Story, K. T.; Vanderlinde, K.; Vieira, J. D.; Vikhlinin, A.; Williamson, R.; Zenteno, A.
2016-11-01
We present the results of SPT-GMOS, a spectroscopic survey with the Gemini Multi-Object Spectrograph (GMOS) on Gemini South. The targets of SPT-GMOS are galaxy clusters identified in the SPT-SZ survey, a millimeter-wave survey of 2500 deg2 of the southern sky using the South Pole Telescope (SPT). Multi-object spectroscopic observations of 62 SPT-selected galaxy clusters were performed between 2011 January and 2015 December, yielding spectra with radial velocity measurements for 2595 sources. We identify 2243 of these sources as galaxies, and 352 as stars. Of the galaxies, we identify 1579 as members of SPT-SZ galaxy clusters. The primary goal of these observations was to obtain spectra of cluster member galaxies to estimate cluster redshifts and velocity dispersions. We describe the full spectroscopic data set and resulting data products, including galaxy redshifts, cluster redshifts, and velocity dispersions, and measurements of several well-known spectral indices for each galaxy: the equivalent width, W, of [O II] λλ3727, 3729 and H-δ, and the 4000 Å break strength, D4000. We use the spectral indices to classify galaxies by spectral type (i.e., passive, post-starburst, star-forming), and we match the spectra against photometric catalogs to characterize spectroscopically observed cluster members as a function of brightness (relative to m⋆). Finally, we report several new measurements of redshifts for ten bright, strongly lensed background galaxies in the cores of eight galaxy clusters. Combining the SPT-GMOS data set with previous spectroscopic follow-up of SPT-SZ galaxy clusters results in spectroscopic measurements for >100 clusters, or ∼20% of the full SPT-SZ sample.
New objects with the B[e] phenomenon in the Large Magellanic Cloud
NASA Astrophysics Data System (ADS)
Levato, H.; Miroshnichenko, A. S.; Saffe, C.
2014-08-01
Aims: The study is aimed at discovering new objects with the B[e] phenomenon in the Large Magellanic Cloud. Methods: We report medium-resolution optical spectroscopic observations of two newly found (ARDB 54 and NOMAD 0181-0125572) and two previously known (Hen S-59 and Hen S-137) supergiants with the B[e] phenomenon in the Large Magellanic Cloud. The observations were obtained with the GMOS spectrograph at the southern Gemini telescope. Results: The optical spectra and the fundamental parameters of ARDB 54 and NOMAD 0181-0125572 are presented for the first time. We found that the Balmer line profiles of Hen S-59 and Hen S-137 were different from those observed in their spectra nearly 20 years ago. We suggest a higher effective temperature and luminosity for both objects. With the new fundamental parameters, the lowest luminosity for known supergiants with the B[e] phenomenon in the Magellanic Clouds is higher that previously thought (log L/L⊙ ~ 4.5 instead of 4.0). The object Hen S-59 may be a binary system based on its UV excess, variable B - V color-index and radial velocity of emission lines, and periodically variable I-band brightness. Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), Ministério da Ciência, Tecnologia e Inovacão (Brazil) and Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina).
Revisiting the Abundance Gradient in the Maser Host Galaxy NGC 4258
NASA Astrophysics Data System (ADS)
Bresolin, Fabio
2011-03-01
New spectroscopic observations of 36 H II regions in NGC 4258 obtained with the Gemini telescope are combined with existing data from the literature to measure the radial oxygen abundance gradient in this galaxy. The [O III]λ4363 auroral line was detected in four of the outermost targets (17-22 kpc from the galaxy center), allowing a determination of the electron temperature Te of the ionized gas. From the use of different calibrations of the R 23 abundance indicator, an oxygen abundance gradient of approximately -0.012 ± 0.002 dex kpc-1 is derived. Such a shallow gradient, combined with the difference in the distance moduli measured from the Cepheid period-luminosity relation by Macri et al. between two distinct fields in NGC 4258, would yield an unrealistically strong effect of metallicity on the Cepheid distances. This strengthens the suggestion that systematic biases might affect the Cepheid distance of the outer field. Evidence for a similar effect in the differential study of M33 by Scowcroft et al. is presented. A revision of the transformation between strong-line and Te -based abundances in Cepheid-host galaxies is discussed. In the Te abundance scale, the oxygen abundance of the inner field of NGC 4258 is found to be comparable with the LMC value. Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the Science and Technology Facilities Council (United Kingdom), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), Ministério da Ciência e Tecnologia (Brazil) and Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina).
The sudden appearance of CO emission in LHA 115-S 65
NASA Astrophysics Data System (ADS)
Oksala, M. E.; Kraus, M.; Arias, M. L.; Borges Fernandes, M.; Cidale, L.; Muratore, M. F.; Curé, M.
2012-10-01
Molecular emission has been detected in several Magellanic Cloud B[e] supergiants. In this Letter, we report on the detection of CO band head emission in the B[e] supergiant LHA 115-S 65, and present a K-band near-infrared spectrum obtained with the Spectrograph for INtegral Field Observation in the Near-Infrared (SINFONI; R= 4500) on the ESO VLT UT4 telescope. The observed molecular band head emission in S65 is quite surprising in the light of a previous non-detection by McGregor, Hyland & McGinn, as well as a high-resolution (R= 50 000) Gemini/Phoenix spectrum of this star taken nine months earlier showing no emission. Based on analysis of the optical spectrum by Kraus, Borges Fernandes & de Araújo, we suspect that the sudden appearance of molecular emission could be due to density build-up in an outflowing viscous disc, as seen for Be stars. This new discovery, combined with variability in two other similar evolved massive stars, indicates an evolutionary link between B[e] supergiants and luminous blue variables. Based on observations obtained with ESO telescopes at the La Silla Paranal Observatory under programme ID 088.D-044 and at the Gemini Observatory which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (USA), the Science and Technology Facilities Council (UK), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), Ministério da Ciência, Tecnologia e Inovação (Brazil) and Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina), under programme ID GS-2010B-Q-31.
Koziróg, Anna; Brycki, Bogumił
2015-01-01
Quaternary ammonium salts (QAS) belong to surfactant commonly used both, in the household and in different branches of industry, primarily in the process of cleaning and disinfection. They have several positive features inter alia effectively limiting the development of microorganisms on many surfaces. In the present work, two compounds were used as biocides: hexamethylene-1,6-bis-(N,N-dimethyl-N-dodecylammonium bromide) that belongs to the gemini surfactant (GS), and its single analogue - dodecyl(trimethyl)ammonium bromide (DTAB). Two fold dilution method was used to determine the minimum concentration of compounds (MIC) which inhibit the growth of bacteria: Staphylococcus aureus (ATCC 6538 and an environmental strain), Pseudomonas aeruginosa (ATCC 85327 and an environmental strain), and yeast Candida albicans (ATCC 11509 and an environmental strain). The viability of cells in liquid cultures with addition of these substances at ¼ MIC, ½ MIC and MIC concentrations were also determined. The obtained results show that DTAB inhibits the growth of bacteria at the concentration of 0.126-1.010 µM/ml, and gemini surfactant is active at 0.036-0.029 µM/ml. Therefore, GS is active at more than 17-70-fold lower concentrations than its monomeric analogue. Strains isolated from natural environment are less sensitive upon testing biocides than the references strains. Both compounds at the MIC value reduced the number of cells of all strains. The use of too low concentration of biocides can limit the growth of microorganisms, but often only for a short period of time in case of special environmental strains. Later on, they can adapt to adverse environmental conditions and begin to evolve defence mechanisms.
NASA Astrophysics Data System (ADS)
Aldrin, Buzz
2002-01-01
I got involved with spaceflight in a peculiar way. I graduated from West Point at a time when there was no Air Force Academy. I went in the Air Force at the time of the Korean War, and while there, I shot down a couple of MIGs. Years later, this led me to want to look at the extension of air travel into space. At MIT, I worked on intercepting other spacecraft. Based upon that education, I got into the space program, not by route of the test pilot school. I was involved in a more esoteric, egg-headed approach. I did help to train the people who were on the first rendezvous missions. I was slated initially on the backup crew for Gemini 10. That meant that I would skip two missions, and then I would fly on the prime crew with the next one. The only trouble was there was no Gemini 13. Because of a tragic aircraft accident that took the lives of the primary crew on Gemini 9, they had to make some crew adjustments. So Jim Lovell and I flew on Gemini 12. On that mission, I was able to take my SCUBA-diving expertise and training underwater for spacewalking and helped to teach some of the Navy people how to do spacewalks. Then, in the infinite wisdom of the Air Force, I was asked to command the test pilot school after I left NASA, even though I had never been through any test pilot training.
GEMINI-TITAN (GT)-3 - WEIGHTLESSNESS EXPERIMENT - AMES RESEARCH CENTER (ARC), CA
1965-03-01
S65-18762 (March 1965) --- Effects of the weightless environment on cell division, the basic growth process for living tissue, will be studied during the Gemini-Titan 3 flight scheduled for March 23, 1965. A spiny black sea urchin (upper left) is stimulated by mild electric shock or potassium chloride. As a result it sheds many thousands of eggs. When fertilized, these eggs become actively dividing cells very similar in basic processes to cells of other animals, including humans. These pictures show stages of cell division. At upper right is a single cell; at lower right cell divisions have produced many cells. Cell photos are magnified about 700 times, and all cells shown are too small to be seen by the naked eye. (Photos at upper right and lower left are of sea urchin eggs. Group of cells at lower right are from a sand dollar, which like the sea urchin, is an Echinoderm. Its eggs are virtually identical and are used interchangeably with those of the sea urchin in NASA Ames Center weightlessness experiments.) The Gemini experiment will involve cell division like that shown here. This will take place during several hours of weightlessness aboard the Gemini spacecraft. The experiment will be flown back to laboratories at Cape Kennedy after spacecraft recovery. It has been designed so that any abnormal cell division found by postflight analysis should suggest that the weightless environment has effects on individual cells. This might mean hazards for prolonged periods of manned spaceflight.
Design, Synthesis and Biological Activities of Novel Gemini 20S-Hydroxyvitamin D3 Analogs
LIN, ZONGTAO; MAREPALLY, SRINIVASA R.; KIM, TAE-KANG; JANJETOVIC, ZORICA; OAK, ALLEN SW.; POSTLETHWAITE, ARNOLD E.; MYERS, LINDA K.; TUCKEY, ROBERT C.; SLOMINSKI, ANDRZEJ T.; MILLER, DUANE D.; LI, WEI
2017-01-01
Vitamin D3 (D3) can be metabolized by cytochrome P450scc (CYP11A1) into 20S-hydroxyvitamin D3 (20D3) as a major metabolite. This bioactive metabolite has shown strong antiproliferative, antifibrotic, pro-differentiation and anti-inflammatory effects while being non-toxic (non-calcemic) at high concentrations. Since D3 analogs with two symmetric side chains (Gemini analogs) result in potent activation of the vitamin D receptor (VDR), we hypothesized that the chain length and composition of these types of analogs also containing a 20-hydroxyl group would affect their biological activities. In this study, we designed and synthesized a series of Gemini 20D3 analogs. Biological tests showed that some of these analogs are partial VDR activators and can significantly stimulate the expression of mRNA for VDR and VDR-regulated genes including CYP24A1 and transient receptor potential cation channel V6 (TRPV6). These analogs inhibited the proliferation of melanoma cells with potency comparable to that of 1α,25-dihydroxyvitamin D3. Moreover, these analogs reduced the level of interferon γ and up-regulated the expression of leukocyte associated immunoglobulin-like receptor 1 in splenocytes, indicating that they have potent anti-inflammatory activities. There are no clear correlations between the Gemini chain length and their VDR activation or biological activities, consistent with the high flexibility of the ligand-binding pocket of the VDR. PMID:26976974
Pietralik, Zuzanna; Kołodziejska, Żaneta; Weiss, Marek; Kozak, Maciej
2015-01-01
The success rate of gene therapy depends on the efficient transfection of genetic material into cells. The golden mean between harmlessness and high effectiveness can be provided by synthetic lipid-like molecules that are similar to the components of biological membranes. Cationic gemini surfactants are one such moiety and because of their favourable physicochemical properties (double positive electric charge, reduced toxicity, low values of critical micelle concentration), they show great potential as delivery system components for genetic material in gene therapy. The aim of this study was to investigate the process of the complexation of cationic gemini surfactants with nucleic acids: double-stranded DNA of different sizes (21 bp, ~185 bp, ~20 kbp) and siRNA (21 bp). The tested series of dicationic surfactants consists of bis-imidazolium quaternary salts with varying lengths of hydrophobic side chains (m = 5, 6, 7, 8, 9, 11, 12, 14, 16). On the basis of the data obtained by circular dichroism spectroscopy and electrophoresis, we concluded that the studied gemini surfactants with long side chains effectively bind nucleic acids at low concentrations, which leads to the formation of stable lipoplexes. Images obtained by atomic force microscopy also confirmed the formation of vesicular structures, i.e., complexes between DNA and surfactants. The cytotoxicity of selected surfactants was also tested on HeLa cells. The surfactant toxicity significantly depends on surfactant geometry (the length of hydrophobic chain).
Pietralik, Zuzanna; Kołodziejska, Żaneta; Weiss, Marek; Kozak, Maciej
2015-01-01
The success rate of gene therapy depends on the efficient transfection of genetic material into cells. The golden mean between harmlessness and high effectiveness can be provided by synthetic lipid-like molecules that are similar to the components of biological membranes. Cationic gemini surfactants are one such moiety and because of their favourable physicochemical properties (double positive electric charge, reduced toxicity, low values of critical micelle concentration), they show great potential as delivery system components for genetic material in gene therapy. The aim of this study was to investigate the process of the complexation of cationic gemini surfactants with nucleic acids: double-stranded DNA of different sizes (21 bp, ~185 bp, ~20 kbp) and siRNA (21 bp). The tested series of dicationic surfactants consists of bis-imidazolium quaternary salts with varying lengths of hydrophobic side chains (m = 5, 6, 7, 8, 9, 11, 12, 14, 16). On the basis of the data obtained by circular dichroism spectroscopy and electrophoresis, we concluded that the studied gemini surfactants with long side chains effectively bind nucleic acids at low concentrations, which leads to the formation of stable lipoplexes. Images obtained by atomic force microscopy also confirmed the formation of vesicular structures, i.e., complexes between DNA and surfactants. The cytotoxicity of selected surfactants was also tested on HeLa cells. The surfactant toxicity significantly depends on surfactant geometry (the length of hydrophobic chain). PMID:26641889
NASA Microclimate Cooling Challenges
NASA Technical Reports Server (NTRS)
Trevino, Luis A.
2004-01-01
The purpose of this outline form presentation is to present NASA's challenges in microclimate cooling as related to the spacesuit. An overview of spacesuit flight-rated personal cooling systems is presented, which includes a brief history of cooling systems from Gemini through Space Station missions. The roles of the liquid cooling garment, thermal environment extremes, the sublimator, multi-layer insulation, and helmet visor UV and solar coatings are reviewed. A second section is presented on advanced personal cooling systems studies, which include heat acquisition studies on cooling garments, heat rejection studies on water boiler & radiators, thermal storage studies, and insulation studies. Past and present research and development and challenges are summarized for the advanced studies.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fischer, Travis C.; Straughn, A. N.; Machuca, C.
2017-01-01
We present near-infrared and optical emission-line and stellar kinematics of the Seyfert 2 galaxy Mrk 573 using the Near-Infrared Field Spectrograph (NIFS) at Gemini North and Dual Imaging Spectrograph at Apache Point Observatory, respectively. By obtaining full kinematic maps of the infrared ionized and molecular gas and stellar kinematics in a ∼700 × 2100 pc{sup 2} circumnuclear region of Mrk 573, we find that kinematics within the Narrow-Line Region are largely due to a combination of both rotation and in situ acceleration of material originating in the host disk. Combining these observations with large-scale, optical long-slit spectroscopy that traces ionized gas emission out tomore » several kpcs, we find that rotation kinematics dominate the majority of the gas. We find that outflowing gas extends to distances less than 1 kpc, suggesting that outflows in Seyfert galaxies may not be powerful enough to evacuate their entire bulges.« less
THE PDS 66 CIRCUMSTELLAR DISK AS SEEN IN POLARIZED LIGHT WITH THE GEMINI PLANET IMAGER
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wolff, Schuyler G.; Greenbaum, Alexandra Z.; Perrin, Marshall
2016-02-10
We present H- and K-band imaging polarimetry for the PDS 66 circumstellar disk obtained during the commissioning of the Gemini Planet Imager (GPI). Polarization images reveal a clear detection of the disk in to the 0.″12 inner working angle (IWA) in the H band, almost three times closer to the star than the previous Hubble Space Telescope (HST) observations with NICMOS and STIS (0.″35 effective IWA). The centro-symmetric polarization vectors confirm that the bright inner disk detection is due to circumstellar scattered light. A more diffuse disk extends to a bright outer ring centered at 80 AU. We discuss several physicalmore » mechanisms capable of producing the observed ring + gap structure. GPI data confirm enhanced scattering on the east side of the disk that is inferred to be nearer to us. We also detect a lateral asymmetry in the south possibly due to shadowing from material within the IWA. This likely corresponds to a temporally variable azimuthal asymmetry observed in HST/STIS coronagraphic imaging.« less
First scattered-light image of the debris disk around HD 131835 with the Gemini Planet Imager
Hung, Li -Wei; Duchêne, Gaspard; Arriaga, Pauline; ...
2015-12-09
Here, we present the first scattered-light image of the debris disk around HD 131835 in the H band using the Gemini Planet Imager. HD 131835 is a ~15 Myr old A2IV star at a distance of ~120 pc in the Sco-Cen OB association. We detect the disk only in polarized light and place an upper limit on the peak total intensity. No point sources resembling exoplanets were identified. Compared to its mid-infrared thermal emission, in scattered light the disk shows similar orientation but different morphology. The scattered-light disk extends from ~75 to ~210 AU in the disk plane with roughlymore » flat surface density. Our Monte Carlo radiative transfer model can describe the observations with a model disk composed of a mixture of silicates and amorphous carbon. In addition to the obvious brightness asymmetry due to stronger forward scattering, we discover a weak brightness asymmetry along the major axis, with the northeast side being 1.3 times brighter than the southwest side at a 3σ level.« less
FIRST SCATTERED-LIGHT IMAGE OF THE DEBRIS DISK AROUND HD 131835 WITH THE GEMINI PLANET IMAGER
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hung, Li-Wei; Arriaga, Pauline; Fitzgerald, Michael P.
2015-12-10
We present the first scattered-light image of the debris disk around HD 131835 in the H band using the Gemini Planet Imager. HD 131835 is a ∼15 Myr old A2IV star at a distance of ∼120 pc in the Sco-Cen OB association. We detect the disk only in polarized light and place an upper limit on the peak total intensity. No point sources resembling exoplanets were identified. Compared to its mid-infrared thermal emission, in scattered light the disk shows similar orientation but different morphology. The scattered-light disk extends from ∼75 to ∼210 AU in the disk plane with roughly flatmore » surface density. Our Monte Carlo radiative transfer model can describe the observations with a model disk composed of a mixture of silicates and amorphous carbon. In addition to the obvious brightness asymmetry due to stronger forward scattering, we discover a weak brightness asymmetry along the major axis, with the northeast side being 1.3 times brighter than the southwest side at a 3σ level.« less
A study of the remarkable galaxy system AM 546-324 (the core of Abell S0546)
NASA Astrophysics Data System (ADS)
Faúndez-Abans, M.; Krabbe, A. C.; de Oliveira-Abans, M.; da Rocha-Poppe, P. C.; Rodrigues, I.; Fernandes-Martin, V. A.; Fernandes, I. F.
2012-07-01
Aims: We report first results of an investigation of the tidally disturbed galaxy system AM 546-324, whose two principal galaxies 2MFGC 04711 and AM 0546-324 (NED02) were previously classified as interacting doubles. This system was selected to study the interaction of ellipticals in a moderately dense environment. We provide spectral characteristics of the system and present an observational study of the interaction effects on the morphology, kinematics, and stellar population of these galaxies. Methods: The study is based on long-slit spectrophotometric data in the range of ~4500-8000 Å obtained with the Gemini Multi-Object Spetrograph at Gemini South (GMOS-S). We have used the stellar population synthesis code STARLIGHT to investigate the star formation history of these galaxies. The Gemini/GMOS-S direct r-G0303 broad band pointing image was used to enhance and study fine morphological structures. The main absorption lines in the spectra were used to determine the radial velocity. Results: Along the whole long-slit signal, the spectra of the Shadowy galaxy (discovered by us), 2MFGC 04711, and AM 0546-324 (NED02) resemble that of an early-type galaxy. We estimated redshifts of z = 0.0696, z = 0.0693 and z = 0.0718, corresponding to heliocentric velocities of 20 141 km s-1, 20 057 km s-1, and 20 754 km s-1 for the Shadowy galaxy, 2MFGC 04711 and AM 0546-324 (NED02), respectively. The central regions of 2MFGC 04711 and AM 0546-324 (NED02) are completely dominated by an old stellar population of 2 × 109 < t ≤ 13 × 109 yr and do not show any spatial variation in the contribution of the stellar-population components. Conclusions: The observed rotation profile distribution of 2MFGC 04711 and AM 0546-324 (NED02) can be adequately interpreted as an ongoing stage of interaction with the Shadowy galaxy as the center of the local gravitational potential-well of the system. The three galaxies are all early-type. The extended and smooth distribution of the material in the Shadowy galaxy is a good laboratory to study direct observational signatures of tidal friction in action. Based on observations made at the Gemini Observatory, under the identification number GS-2010B-Q-7.
Microscopic description of production cross sections including deexcitation effects
NASA Astrophysics Data System (ADS)
Sekizawa, Kazuyuki
2017-07-01
Background: At the forefront of the nuclear science, production of new neutron-rich isotopes is continuously pursued at accelerator laboratories all over the world. To explore the currently unknown territories in the nuclear chart far away from the stability, reliable theoretical predictions are inevitable. Purpose: To provide a reliable prediction of production cross sections taking into account secondary deexcitation processes, both particle evaporation and fission, a new method called TDHF+GEMINI is proposed, which combines the microscopic time-dependent Hartree-Fock (TDHF) theory with a sophisticated statistical compound-nucleus deexcitation model, GEMINI++. Methods: Low-energy heavy ion reactions are described based on three-dimensional Skyrme-TDHF calculations. Using the particle-number projection method, production probabilities, total angular momenta, and excitation energies of primary reaction products are extracted from the TDHF wave function after collision. Production cross sections for secondary reaction products are evaluated employing GEMINI++. Results are compared with available experimental data and widely used grazing calculations. Results: The method is applied to describe cross sections for multinucleon transfer processes in 40Ca+124Sn (Ec .m .≃128.54 MeV ), 48Ca+124Sn (Ec .m .≃125.44 MeV ), 40Ca+208Pb (Ec .m .≃208.84 MeV ), 58Ni+208Pb (Ec .m .≃256.79 MeV ), 64Ni+238U (Ec .m .≃307.35 MeV ), and 136Xe+198Pt (Ec .m .≃644.98 MeV ) reactions at energies close to the Coulomb barrier. It is shown that the inclusion of secondary deexcitation processes, which are dominated by neutron evaporation in the present systems, substantially improves agreement with the experimental data. The magnitude of the evaporation effects is very similar to the one observed in grazing calculations. TDHF+GEMINI provides better description of the absolute value of the cross sections for channels involving transfer of more than one proton, compared to the grazing results. However, there remain discrepancies between the measurements and the calculated cross sections, indicating a limit of the theoretical framework that works with a single mean-field potential. Possible causes of the discrepancies are discussed. Conclusions: To perfectly reproduce experimental cross sections for multinucleon transfer processes, one should go beyond the standard self-consistent mean-field description. Nevertheless, the proposed method will provide valuable information to optimize production mechanisms of new neutron-rich nuclei through its microscopic, nonempirical predictions.
Post-Coronagraph Wavefront Sensor for Gemini Planet Imager
NASA Technical Reports Server (NTRS)
Wallace, J. Kent; Burruss, Rick; Pueyo, Laurent; Soummer, Remi; Shelton, Chris; Bartos, Randall; Fregoso, Felipe; Nemati, Bijan; Best, Paul; Angione, John
2009-01-01
The calibration wavefront system for the Gemini Planet Imager (GPI) will measure the complex wavefront at the apodized pupil and provide slow phase errors to the AO system to mitigate against image plane speckles that would cause a loss in contrast. This talk describes both the low-order and high-order sensors in the calibration wavefront sensor and how the information is combined to form the wavefront estimate before the coronagraph. We will show laboratory results from our calibration testbed that demonstrate the subsystem performance at levels commensurate with those required on the final instrument.
GEMINI-TITAN (GT)-10 - EARTH SKY - RENDEZVOUS - OUTER SPACE
1966-07-18
S66-46122 (18 July 1966) --- Agena Target Docking Vehicle 5005 is photographed from the Gemini-Titan 10 (GT-10) spacecraft during rendezvous in space. The two spacecraft are about 38 feet apart. After docking with the Agena, astronauts John W. Young, command pilot, and Michael Collins, pilot, fired the 16,000 pound thrust engine of Agena X's primary propulsion system to boost the combined vehicles into an orbit with an apogee of 413 nautical miles to set a new altitude record for manned spaceflight. Photo credit: NASA
2006-11-14
Spectroscopic Data- Observations Longslit spectra of SNLS SN candidates were taken at the Gemini telescopes with the Gemini Multi-Object Spectrograph [ GMOS ...typical i’ magnitudes ranged from 21.8 to 24.5), and required exposure times of 1 to 2 hours over two to four exposures. The GMOS R400 grating (400 lines...extra 360 seconds. The extra overhead time is often minimised by choosing a small nod distance, or by employing the Electronic N&S mode. The GMOS
GEMINI-TITAN (GT)-3 - EARTH- SKY VIEW
1965-03-23
S65-18740 (23 March 1965) --- Astronaut John W. Young took this picture during the second orbit of the Gemini-Titan 3 three-orbit mission as the spacecraft "Molly Brown" passed over Northern Mexico at an altitude of 90 miles. The light-brown circular area at the lower right is the Sonoran Desert. The lower portion of the picture is Mexico, and the upper part is California. Young used a hand-held modified 70mm Hasselblad camera with color film. The lens setting was 250th of a second at f/11.
Mississippi River delta as seen from the Gemini 9-A spacecraft
NASA Technical Reports Server (NTRS)
1966-01-01
The Mississippi River delta, and Gulf coasts of Louisiana, Mississippi, Alabama and Florida as seen from the Gemini 9-A spacecraft during its first revolution of the earth. Florida peninsula is seen at upper right corner of picture. lake Pontchartrain is at lower left. new orleans is located between the lake and the U-shaped bend in the river. Large bay at top left center is Mobile Bay. Apalachicola, Florida, is the point of land at top center of picture. Note alluvial deposit at mouths of Mississippi.
Organizational transformation to improve operational efficiency at Gemini South
NASA Astrophysics Data System (ADS)
van der Hoeven, M.; Maltes, Diego; Rogers, Rolando
2016-07-01
In this paper we will describe how the Gemini South Engineering team has been reorganized from different functional units into a cross-disciplinary team while executing a transition plan that imposes several staff reductions, driven by budget reductions. Several factors are of critical importance to the success of any change in organization. Budgetary processes, staff diversity, leadership style, skill sets and planning are all important factors to take into account to achieve a successful outcome. We will analyze the organizational alignment by using some proven management models and concepts.
GEMINI-TITAN (GT)-4 - EARTH-SKY VIEW
1965-06-01
S65-34661 (3-7 June 1965) --- Among the photographs of Earth's terrain taken from the Gemini-4 spacecraft during its orbital mission was this view of the southeastern tip of the Arabian Peninsula with the Gulf of Oman at upper right. Seif dunes (sand) at lower left. This picture was taken with a modified 70mm Hasselblad camera, using Eastman color film, ASA 64 at a setting of 250th of a second at f/11. Dr. Paul Lowman Jr., NASA geologist, was in charge of the Synoptic Terrain Photography.
VizieR Online Data Catalog: Imaging and spectroscopy in Lynx W (Jorgensen+, 2014)
NASA Astrophysics Data System (ADS)
Jorgensen, I.; Chiboucas, K.; Toft, S.; Bergmann, M.; Zirm, A.; Schiavon, R. P.; Grutzbauch, R.
2017-01-01
Ground-based imaging of RX J0848.6+4453 was obtained primarily to show the performance gain provided by replacing the original E2V charge-coupled devices (E2V CCDs) in Gemini Multi-Object Spectrograph on Gemini North (GMOS-N) with E2V Deep Depletion CCDs (E2V DD CCDs). This replacement was done in 2011 October. Imaging of RX J0848.6+4453 was obtained with the original E2V CCDs in 2011 October (UT 2011 Oct 1 to 2011 Oct 2; Program ID: GN-2011B-DD-3) and repeated with the E2V DD CCDs in 2011 November. The imaging was done in the z' filter. For the observations with the original E2V CCDs the total exposure time was 60 minutes (obtained as 12 five-minute exposures) and the co-added image had an image quality of FWHM=0.52'' measured from point sources in the field. For the E2V DD CCDs a total exposure time of 55 minutes was obtained and the resulting image quality was FWHM=0.51''. Imaging of RX J0848.6+4453 was also obtained with Hubble Space Telescope /Advanced Camera for Surveys (HST/ACS using the filters F775W and F850LP) under the program ID 9919. The spectroscopic observations were obtained in multi-object spectroscopic (MOS) mode with GMOS-N (UT 2011 Nov 24 to 2012 Jan 4, Program ID: GN-2011B-DD-5; UT 2013 Mar 9 to 2013 May 18, Program ID: GN-2013A-Q-65). Table10 lists the photometric parameters for the spectroscopic sample as derived from the HST/ACS observations in F850LP and F775W. Tables 11 and 12 list the results from the template fitting and the derived line strengths, respectively. (3 data files).
NASA Astrophysics Data System (ADS)
Lederer, S. M.; Osip, D. J.; Thomas-Osip, J. E.; DeBuizer, J. M.; Mondragon, L. A.; Schweiger, D. L.; Viehweg, J.; SB Collaboration
2005-08-01
An extensive observing campaign to monitor Comet 9P/Tempel 1 will be conducted from 20 June to 19 July, 2005 at Las Campanas Observatory, Chile. These observations will precede and follow the impact of the Deep Impact projectile, which is likely to create a crater on the nucleus that will act as a fresh active area on the surface of the comet. Discreet nucleus active areas, believed to be the source of coma gas and dust jets, will likely result in changing morphology in the coma. We present the initial results of the wide-field narrowband visible imaging of the comet. Data will be taken with the 2.5m DuPont telescope from 27 June - 9 July, following the comet from 4 rotations prior to impact, to 4 rotations after impact using the narrowband Hale-Bopp filters, including CN, C2, and two continuum filters. These data will allow an accurate determination of the rotation state of the embedded nucleus immediately preceding the impact event as well as a measure of any changes to the rotation state due to the impact. In addition, modeling of these data will provide the total dust and gas production rates from the unaltered nucleus compared to the enhanced dust and gas emission from the newly created active region and freely sublimating pieces of mantle material ejected into the coma by the impactor. We will monitor temporal changes (on hours and days time-scales) in the morphology of both the gas and refractory components. We will use coma morphology studies to estimate the dust and gas outflow velocities and infer the presence of discreet nucleus source regions (pre- and post-impact). Of particular interest is the study of the gas-to-dust ratio and the ratio of the minor carbon species emitted from the newly created active region relative to the pre-impact coma environment.
A SYSTEMATIC SURVEY OF PROTOCLUSTERS AT z ∼ 3–6 IN THE CFHTLS DEEP FIELDS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Toshikawa, Jun; Kashikawa, Nobunari; Furusawa, Hisanori
2016-08-01
We present the discovery of three protoclusters at z ∼ 3–4 with spectroscopic confirmation in the Canada–France–Hawaii Telescope Legacy Survey Deep Fields. In these fields, we investigate the large-scale projected sky distribution of z ∼ 3–6 Lyman-break galaxies and identify 21 protocluster candidates from regions that are overdense at more than 4 σ overdensity significance. Based on cosmological simulations, it is expected that more than 76% of these candidates will evolve into a galaxy cluster of at least a halo mass of 10{sup 14} M {sub ⊙} at z = 0. We perform follow-up spectroscopy for eight of the candidatesmore » using Subaru/FOCAS, Keck II/DEIMOS, and Gemini-N/GMOS. In total we target 462 dropout candidates and obtain 138 spectroscopic redshifts. We confirm three real protoclusters at z = 3–4 with more than five members spectroscopically identified and find one to be an incidental overdense region by mere chance alignment. The other four candidate regions at z ∼ 5–6 require more spectroscopic follow-up in order to be conclusive. A z = 3.67 protocluster, which has 11 spectroscopically confirmed members, shows a remarkable core-like structure composed of a central small region (<0.5 physical Mpc) and an outskirts region (∼1.0 physical Mpc). The Ly α equivalent widths of members of the protocluster are significantly smaller than those of field galaxies at the same redshift, while there is no difference in the UV luminosity distributions. These results imply that some environmental effects start operating as early as at z ∼ 4 along with the growth of the protocluster structure. This study provides an important benchmark for our analysis of protoclusters in the upcoming Subaru/HSC imaging survey and its spectroscopic follow-up with the Subaru/PFS that will detect thousands of protoclusters up to z ∼ 6.« less
A Systematic Survey of Protoclusters at z ~ 3-6 in the CFHTLS Deep Fields
NASA Astrophysics Data System (ADS)
Toshikawa, Jun; Kashikawa, Nobunari; Overzier, Roderik; Malkan, Matthew A.; Furusawa, Hisanori; Ishikawa, Shogo; Onoue, Masafusa; Ota, Kazuaki; Tanaka, Masayuki; Niino, Yuu; Uchiyama, Hisakazu
2016-08-01
We present the discovery of three protoclusters at z ˜ 3-4 with spectroscopic confirmation in the Canada-France-Hawaii Telescope Legacy Survey Deep Fields. In these fields, we investigate the large-scale projected sky distribution of z ˜ 3-6 Lyman-break galaxies and identify 21 protocluster candidates from regions that are overdense at more than 4σ overdensity significance. Based on cosmological simulations, it is expected that more than 76% of these candidates will evolve into a galaxy cluster of at least a halo mass of 1014 M ⊙ at z = 0. We perform follow-up spectroscopy for eight of the candidates using Subaru/FOCAS, Keck II/DEIMOS, and Gemini-N/GMOS. In total we target 462 dropout candidates and obtain 138 spectroscopic redshifts. We confirm three real protoclusters at z = 3-4 with more than five members spectroscopically identified and find one to be an incidental overdense region by mere chance alignment. The other four candidate regions at z ˜ 5-6 require more spectroscopic follow-up in order to be conclusive. A z = 3.67 protocluster, which has 11 spectroscopically confirmed members, shows a remarkable core-like structure composed of a central small region (<0.5 physical Mpc) and an outskirts region (˜1.0 physical Mpc). The Lyα equivalent widths of members of the protocluster are significantly smaller than those of field galaxies at the same redshift, while there is no difference in the UV luminosity distributions. These results imply that some environmental effects start operating as early as at z ˜ 4 along with the growth of the protocluster structure. This study provides an important benchmark for our analysis of protoclusters in the upcoming Subaru/HSC imaging survey and its spectroscopic follow-up with the Subaru/PFS that will detect thousands of protoclusters up to z ˜ 6.
Cost analysis of water recovery systems
NASA Technical Reports Server (NTRS)
Yakut, M. M.
1972-01-01
Cost and performance data from Gemini, Skylab, and other aerospace and biotechnology programs were analyzed to identify major cost elements required to establish cost estimating relationships for advanced life support subsystems for long range planning in support of earth orbital programs. Cost analysis are presented for five leading water reclamation systems; (1) RITE waste management-water system;(2) reverse osmosis system;(3) multifiltration system;(4) vapor compression system; and(5) closed air evaporation system with electrolytic pretreatment.
SN 1987A after 18 Years: Mid-Infrared Gemini and Spitzer Observations of the Remnant
NASA Astrophysics Data System (ADS)
Bouchet, Patrice; Dwek, Eli; Danziger, John; Arendt, Richard G.; De Buizer, I. James M.; Park, Sangwook; Suntzeff, Nicholas B.; Kirshner, Robert P.; Challis, Peter
2006-10-01
Using the Gemini South 8 m telescope, we obtained high-resolution 11.7 and 18.3 μm mid-IR images of SN 1987A on day 6526 since the explosion. All the emission arises from the equatorial ring. Nearly contemporaneous spectra obtained at 5-38 μm with the Spitzer Space Telescope show that this is thermal emission from silicate dust that condensed out in the red giant wind of the progenitor star. The dust temperature is 166+18-12 K, and the emitting dust mass is 2.6+2.0-1.4×10-6 Msolar. Comparison of the Gemini 11.7 μm image with Chandra X-ray images, HST UV-optical images, and ATCA radio synchrotron images shows generally good correlation across all wavelengths. If the dust resides in the diffuse X-ray-emitting gas then it is collisionally heated. The IR emission can then be used to derive the plasma temperature and density, which were found to be in good agreement with those inferred from the X-rays. Alternatively, the dust could reside in the dense UV-optical knots and be heated by the radiative shocks that are propagating through the knots. In either case the dust-to-gas mass ratio in the CSM around the supernova is significantly lower than that in the general interstellar medium of the LMC, suggesting either a low condensation efficiency in the wind of the progenitor star or the efficient destruction of the dust by the SN blast wave. Overall, we are witnessing the interaction of the SN blast wave with its surrounding medium, creating an environment that is rapidly evolving at all wavelengths. Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy (AURA), Inc., under cooperative agreement with the National Science Foundation (NSF) on behalf of the Gemini partnership: the NSF (United States), the Particle Physics and Astronomy research Council (United Kingdom), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), CNPq (Brazil), and CONICET (Argentina).
Vesicles from pH-regulated reversible gemini amino-acid surfactants as nanocapsules for delivery.
Lv, Jing; Qiao, Weihong; Li, Zongshi
2016-10-01
Reversible transition from micelles to vesicles by regulating pH were realized by gemini amino-acid surfactants N,N'-dialkyl-N,N'-diacetate ethylenediamine. Measurement results of ζ-potential at different pH and DLS at varying solvents revealed that the protonation between H(+) and double NCH2COO(-) groups (generating NH(+)CH2COO(-)), expressed as pKa1 and pKa2, is the key driving force to control the aggregation behaviors of gemini surfactant molecule. Effect of pH on the bilayer structure was studied in detail by using steady-state fluorescence spectroscopy of hydrophobic pyrene and Coumarin 153 (C153) respectively and fluorescence resonance energy transfer (FRET) from C153 to Rhodamine 6G (R6G). Various pH-regulated and pH-reversible self-assemblies were obtained in one surfactant system. Vitamin D3 was encapsulated in vesicle bilayers to form nano-VD3-capsules as VD3 supplement agent for health care products. By using the electrostatic attraction between Ca(2+) and double -COO(-) groups, nano-VD3-capsules with Ca(2+) coated outermost layers were prepared as a formulation for VD3 and calcium co-supplement agent. DLS and TEM were performed to check stability and morphology of the nano-capsules. It is concluded that the pH-regulated gemini amino-acid surfactants can be used to construct colloidal systems for delivering hydrophobic drugs or nutritions without lipids at human physiological pH level. Copyright © 2016 Elsevier B.V. All rights reserved.
Circumnuclear star formation in Mrk 42 mapped with Gemini Near-infrared Integral Field Spectrograph
NASA Astrophysics Data System (ADS)
Hennig, Moiré G.; Riffel, Rogemar A.; Dors, O. L.; Riffel, Rogerio; Storchi-Bergmann, Thaisa; Colina, Luis
2018-06-01
We present Gemini Near-infrared Integral Field Spectrograph (NIFS) observations of the inner 1.5 × 1.5 kpc2 of the narrow-line Seyfert 1 galaxy Mrk 42 at a spatial resolution of 60 pc and spectral resolution of 40 km s^{-1}. The emission-line flux and equivalent width maps clearly show a ring of circumnuclear star formation regions surrounding the nucleus with radius of ˜500 pc. The spectra of some of these regions show molecular absorption features which are probably of CN, TiO, or VO, indicating the presence of massive evolved stars in the thermally pulsing asymptotic giant branch phase. The gas kinematics of the ring is dominated by rotation in the plane of the galaxy, following the large-scale disc geometry, while at the nucleus an additional outflowing component is detected blueshifted by 300-500 km s^{-1}, relative to the systemic velocity of the galaxy. Based on the equivalent width of Br γ we find pieces of evidence of gradients in the age of H II regions along the ring of Mrk 42, favouring the pearls on a string scenario of star formation. The broad component of Pa β emission line presents a Full Width at Half Maximum of ˜1480 km s^{-1}, implying in a mass of ˜2.5 × 106 M⊙ for the central supermassive black hole. Based on emission-line ratios we conclude that besides the active galactic nucleus, Mrk 42 presents nuclear Starburst activity.
He, Wei; Zhang, Yi; Li, Jiehua; Gao, Yunlong; Luo, Feng; Tan, Hong; Wang, Kunjie; Fu, Qiang
2016-08-26
Contact-active antibacterial surfaces play a vital role in preventing bacterial contamination of artificial surfaces. In the past, numerous researches have been focused on antibacterial surfaces comprising of antifouling upper-layer and antibacterial sub-layer. In this work, we demonstrate a reversed surface structure which integrate antibacterial upper-layer and antifouling sub-layer. These surfaces are prepared by simply casting gemini quaternary ammonium salt waterborne polyurethanes (GWPU) and their blends. Due to the high interfacial energy of gemini quaternary ammonium salt (GQAS), chain segments containing GQAS can accumulate at polymer/air interface to form an antibacterial upper-layer spontaneously during the film formation. Meanwhile, the soft segments composed of polyethylene glycol (PEG) formed the antifouling sub-layer. Our findings indicate that the combination of antibacterial upper-layer and antifouling sub-layer endow these surfaces strong, long-lasting antifouling and contact-active antibacterial properties, with a more than 99.99% killing efficiency against both gram-positive and gram-negative bacteria attached to them.
Space-Proven Medical Monitor: The Total Patient-Care Package
NASA Technical Reports Server (NTRS)
2006-01-01
The primary objective of the Gemini Program was to develop techniques that would allow for advanced, long-duration space travel, a prerequisite of the ensuing Apollo Program that would put man safely on the Moon before the end of the decade. In order to carry out this objective, NASA worked with a variety of innovative companies to develop propulsion systems, onboard computers, and docking capabilities that were critical to the health of Gemini spacecraft, as well as life-support systems and physiological-monitoring devices that were critical to the health of Gemini astronauts. One of these companies was Spacelabs Medical, Inc., the pioneer of what is commonly known today as medical telemetry. Spacelabs Medical helped NASA better understand man s reaction to space through a series of bioinstrumentation devices that, for the first time ever, were capable of monitoring orbiting astronauts physical conditions in real time, from Earth. The company went on to further expand its knowledge of monitoring and maintaining health in space, and then brought it down to Earth, to dramatically change the course of patient monitoring in the field of health care.
Pan, Zhicheng; Fang, Danxuan; Song, Yuanqing; Song, Nijia; Ding, Mingming; Li, Jiehua; Luo, Feng; Li, Jianshu; Tan, Hong; Fu, Qiang
2018-06-06
Cationic gemini quaternary ammonium (GQA) has been used as a cell internalization promoter to improve the permeability of the cell membrane and enhance the cellular uptake. However, the effect of the alkyl chain length on the cellular properties of nanocarriers has not been elucidated yet. In this study, we developed a series of polyurethane micelles containing GQAs with various alkyl chain lengths. The alteration of the gemini alkyl chain length was found to change the distribution of GQA surfactants in the micellar structure and affect the surface charge exposure, stability, and the protein absorption properties of nanocarriers. Moreover, we also clarified the role of the alkyl chain length in tumor cell internalization and macrophage uptake of polyurethane micelles. This work provides a new understanding on the effect of the GQA alkyl chain length on the physicochemical and biological properties of nanomedicines, and offers guidance on the rational design of effective drug delivery systems where the issue of functional group exposure at the micellar surface should be considered.
He, Wei; Zhang, Yi; Li, Jiehua; Gao, Yunlong; Luo, Feng; Tan, Hong; Wang, Kunjie; Fu, Qiang
2016-01-01
Contact-active antibacterial surfaces play a vital role in preventing bacterial contamination of artificial surfaces. In the past, numerous researches have been focused on antibacterial surfaces comprising of antifouling upper-layer and antibacterial sub-layer. In this work, we demonstrate a reversed surface structure which integrate antibacterial upper-layer and antifouling sub-layer. These surfaces are prepared by simply casting gemini quaternary ammonium salt waterborne polyurethanes (GWPU) and their blends. Due to the high interfacial energy of gemini quaternary ammonium salt (GQAS), chain segments containing GQAS can accumulate at polymer/air interface to form an antibacterial upper-layer spontaneously during the film formation. Meanwhile, the soft segments composed of polyethylene glycol (PEG) formed the antifouling sub-layer. Our findings indicate that the combination of antibacterial upper-layer and antifouling sub-layer endow these surfaces strong, long-lasting antifouling and contact-active antibacterial properties, with a more than 99.99% killing efficiency against both gram-positive and gram-negative bacteria attached to them. PMID:27561546
NASA Astrophysics Data System (ADS)
Howell, D. A.; Sullivan, M.; Perrett, K.; Bronder, T. J.; Hook, I. M.; Astier, P.; Aubourg, E.; Balam, D.; Basa, S.; Carlberg, R. G.; Fabbro, S.; Fouchez, D.; Guy, J.; Lafoux, H.; Neill, J. D.; Pain, R.; Palanque-Delabrouille, N.; Pritchet, C. J.; Regnault, N.; Rich, J.; Taillet, R.; Knop, R.; McMahon, R. G.; Perlmutter, S.; Walton, N. A.
2005-12-01
We present new techniques for improving the efficiency of supernova (SN) classification at high redshift using 64 candidates observed at Gemini North and South during the first year of the Supernova Legacy Survey (SNLS). The SNLS is an ongoing 5 year project with the goal of measuring the equation of state of dark energy by discovering and following over 700 high-redshift SNe Ia using data from the Canada-France-Hawaii Telescope Legacy Survey. We achieve an improvement in the SN Ia spectroscopic confirmation rate: at Gemini 71% of candidates are now confirmed as SNe Ia, compared to 54% using the methods of previous surveys. This is despite the comparatively high redshift of this sample, in which the median SN Ia redshift is z=0.81 (0.155<=z<=1.01). These improvements were realized because we use the unprecedented color coverage and light curve sampling of the SNLS to predict whether a candidate is a SN Ia and to estimate its redshift, before obtaining a spectrum, using a new technique called the ``SN photo-z.'' In addition, we have improved techniques for galaxy subtraction and SN template χ2 fitting, allowing us to identify candidates even when they are only 15% as bright as the host galaxy. The largest impediment to SN identification is found to be host galaxy contamination of the spectrum-when the SN was at least as bright as the underlying host galaxy the target was identified more than 90% of the time. However, even SNe in bright host galaxies can be easily identified in good seeing conditions. When the image quality was better than 0.55", the candidate was identified 88% of the time. Over the 5 year course of the survey, using the selection techniques presented here, we will be able to add ~170 more confirmed SNe Ia than would be possible using previous methods. APC, 11 Place Marcelin Berthelot, 75231 Paris Cedex 05, France. DSM/DAPNIA, CEA/Saclay, 91191 Gif-sur-Yvette Cedex, France.
A Luminous Lyα-emitting Galaxy at Redshift z = 6.535: Discovery and Spectroscopic Confirmation
NASA Astrophysics Data System (ADS)
Rhoads, James E.; Xu, Chun; Dawson, Steve; Dey, Arjun; Malhotra, Sangeeta; Wang, JunXian; Jannuzi, Buell T.; Spinrad, Hyron; Stern, Daniel
2004-08-01
We present a redshift z=6.535 galaxy discovered by its Lyα emission in a 9180 Å narrowband image from the Large Area Lyman Alpha survey. The Lyα line luminosity (1.1×1043 ergs s-1) is among the largest known for star-forming galaxies at z~6.5. The line shows the distinct asymmetry that is characteristic of high-redshift Lyα. The 2 σ lower bound on the observer-frame equivalent width is greater than 530 Å. This is hard to reconcile with a neutral intergalactic medium (IGM) unless the Lyα line is intrinsically strong and is emitted from its host galaxy with an intrinsic Doppler shift of several hundred km s-1. If the IGM is ionized, it corresponds to a rest-frame equivalent width greater than 40 Å after correcting for Lyα forest absorption. We also present a complete spectroscopic follow-up of the remaining candidates with line flux greater than 2×10-17 ergs cm-2 s-1 in our 1200 arcmin2 narrowband image. These include another galaxy with a strong emission line at 9136 Å and no detected continuum flux, which, however, is most likely an [O III] λ5007 source at z=0.824, on the basis of a weak detection of the [O III] λ4959 line. The data presented in this paper were obtained at the Kitt Peak National Observatory, the Gemini Observatory, and the W. M. Keck Observatory. Kitt Peak National Observatory, National Optical Astronomy Observatory, is operated by the Association of Universities for Research in Astronomy, Inc. (AURA), under cooperative agreement with the National Science Foundation (NSF). The Gemini Observatory is operated by AURA under a cooperative agreement with the NSF on behalf of the Gemini partnership: the NSF (United States), the Particle Physics and Astronomy Research Council (United Kingdom), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council, CNPq (Brazil), and CONICET (Argentina). The W. M. Keck Observatory is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Keck Observatory was made possible by the generous financial support of the W. M. Keck Foundation.
GEMINI-TITAN (GT)-3 - EARTH-SKY VIEWS - CA
1965-03-23
S65-18741 (23 March 1965) --- Astronaut John W. Young took this picture during the Gemini-Titan 3 three-orbit mission as the spacecraft "Molly Brown" passed over Northern Mexico. The large light-brown area is the Sonoran Desert. The Colorado River runs from upper right to lower left. The lower portion of the picture is Mexico, the upper left is California, and the upper right is Arizona. The altitude of the spacecraft was 90 miles. Young used a hand-held modified 70mm Hasselblad camera with color film. The lens setting was 250th of a second at f/11.
Spacecraft cryogenic gas storage systems
NASA Technical Reports Server (NTRS)
Rysavy, G.
1971-01-01
Cryogenic gas storage systems were developed for the liquid storage of oxygen, hydrogen, nitrogen, and helium. Cryogenic storage is attractive because of the high liquid density and low storage pressure of cryogens. This situation results in smaller container sizes, reduced container-strength levels, and lower tankage weights. The Gemini and Apollo spacecraft used cryogenic gas storage systems as standard spacecraft equipment. In addition to the Gemini and Apollo cryogenic gas storage systems, other systems were developed and tested in the course of advancing the state of the art. All of the cryogenic storage systems used, developed, and tested to date for manned-spacecraft applications are described.
Orienete Province, eastern end of Cuba as seen from Gemini 7 spacecraft
1965-12-05
S65-63826 (5 Dec. 1965) --- Oriente Province, eastern end of Cuba, as seen from the National Aeronautics and Space Administration's Gemini-7 spacecraft during its 14th revolution of Earth. Guantanamo Bay is in the center of the picture on the southern coast of Cuba. Santiago de Cuba is located about one inch from the bottom edge of the picture, or about three inches westward down the coast from Guantanamo. This photograph was taken with a modified 70mm Hasselblad camera, using Eastman Kodak, Ektachrome MS (S.O. 217) color film. Photo credit: NASA
TRAINING - GEMINI-TITAN (GT)-5 - TX
1965-06-18
S65-35563 (18 June 1965) --- Astronauts L. Gordon Cooper Jr. (left), command pilot; and Charles Conrad Jr., pilot, the prime crew of the Gemini-5 spaceflight, prepare their cameras while aboard a C-130 aircraft flying near Laredo, Texas. The two astronauts are taking part in a series of visual acuity experiments to aid them in learning to identify known terrestrial features under controlled conditions. Knowledge gained from these experiments will have later application for space pilots identifying terrestrial features from space. Dr. John Billingham, chief, Environmental Physiology Branch, Crew Systems Division, is in charge of the Visual Acuity Experiments.
2016-11-07
Inside the Heroes and Legends attraction at the Kennedy Space Center Visitor Complex guests watch a video presentation depicting the International Space Station in Earth orbit. In addition to displays honoring the Americans currently enshrined in the U. S. Astronaut Hall of Fame, the new facility looks back to the pioneering efforts of Mercury, Gemini and Apollo. It sets the stage by providing the background and context for space exploration and the legendary men and women who pioneered the nation's journey into space.
Central structures of Seyfert galaxy NGC 1672
NASA Astrophysics Data System (ADS)
Firpo, V.; Díaz, R.; Dottori, H.; Aguero, M. P.; Bosch, G.; Hagele, G.; Cardaci, M.; Dors, O.
2017-10-01
We present the velocity field of the inner 4"(350 pc) of NGC1672, observed with Gemini GMOS/IFU with a spatial sampling of 0.2", spatial resolution of 0.4", and spectral resolution 6000. We determine an upper limit for the mass of the SMBH in the LINER core using the ionized gas radial velocity field, and we confirmed that the active galactic nucleus is located off-center respect to the circumnuclear disk rotation symmetry center.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Horch, Elliott P.; Van Altena, William F.; Demarque, Pierre
2015-05-15
In an effort to better understand the details of the stellar structure and evolution of metal-poor stars, the Gemini North telescope was used on two occasions to take speckle imaging data of a sample of known spectroscopic binary stars and other nearby stars in order to search for and resolve close companions. The observations were obtained using the Differential Speckle Survey Instrument, which takes data in two filters simultaneously. The results presented here are of 90 observations of 23 systems in which one or more companions was detected, and six stars where no companion was detected to the limit ofmore » the camera capabilities at Gemini. In the case of the binary and multiple stars, these results are then further analyzed to make first orbit determinations in five cases, and orbit refinements in four other cases. The mass information is derived, and since the systems span a range in metallicity, a study is presented that compares our results with the expected trend in total mass as derived from the most recent Yale isochrones as a function of metal abundance. These data suggest that metal-poor main-sequence stars are less massive at a given color than their solar-metallicity analogues in a manner consistent with that predicted from the theory.« less
The Near-Earth Encounter of Asteroid 308635 (2005 YU55): Thermal IR Observations
NASA Technical Reports Server (NTRS)
Lim, Lucy F.; Emery, J. P.; Moskovitz, N. A.; Busch, N. W.; Yang, B.; Granvik, M.
2012-01-01
The near-Earth approach (0.00217 AU, or 0.845 lunar distances) of the C-type asteroid 308635 (2005 YU55) in November 2011 presented a rare opportunity for detailed observations of a low-albedo NEA in this size range. As part of a multi-telescope campaign to measure visible and infrared spectra and photometry, we obtained mid-infrared (approx. 8 to 22 micron) photometry and spectroscopy of 2005 YU55 using Michelle on the Gemini North telescope on UT November 9 and 10,2011. An extensive radar campaign together with optical light-curves established the rotation state of YU55. In addition, the radar imaging resulted in a shape model for the asteroid, detection of numerous boulders on its surface, and a preliminary estimate of its equatorial diameter at 380 +/- 20 m. In a preliminary analysis, applying the radar and lightcurve-derived parameters to a rough-surface thermophysical model fit to the Gemini/Michelle thermal emission photometry results in a thermal inertia range of approximately 500 to 1500 J/sq m/0.5s/K, with the low-thermal-inertia solution corresponding to the small end of the radar size range and vice versa. Updates to these results will be presented and modeling of the thermal contribution to the measured near-infrared spectra from Palomar/Triplespec and IRTF/SpeX will also be discussed.
Alejo, T; Merchán, M D; Velázquez, M M
2014-08-26
We used quartz crystal microbalance with dissipation to study the mechanical properties, the kinetics of adsorption, and the amount of CdSe quantum dots (QDs) adsorbed onto a SiO2 sensor, referred as bare sensor, onto the sensor modified with a film of the polymer poly(maleic anhydride-alt-1-octadecene), PMAO, or with a film of the Gemini surfactant ethyl-bis(dimethyl octadecyl ammonium bromide), abbreviated as 18-2-18. Results showed that when the sensor is coated with polymer or surfactant molecules, the coverage increases compared with that obtained for the bare sensor. On the other hand, rheological properties and kinetics of adsorption of QDs are driven by QD nanoparticles. Thus, the QD films present elastic behavior, and the elasticity values are independent of the molecule used as coating and similar to the elasticity value obtained for QDs films on the bare sensor. The QD adsorption is a two-step mechanism in which the fastest process is attributed to the QD adsorption onto the solid substrate and the slowest one is ascribed to rearrangement movements of the nanoparticles adsorbed at the surface.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nielsen, Eric L.; De Rosa, Robert J.; Wang, Jason
Here, we present new spatially resolved astrometry and photometry from the Gemini Planet Imager of the inner binary of the young multiple star system V343 Normae, which is a member of the β Pictoris (β Pic) moving group. V343 Normae comprises a K0 and mid-M star in a ~4.5 year orbit (AaAb) and a wide 10'' M5 companion (B). By combining these data with archival astrometry and radial velocities we fit the orbit and measure individual masses for both components ofmore » $${M}_{\\mathrm{Aa}}=1.10\\pm 0.10\\,{M}_{\\odot }$$ and $${M}_{\\mathrm{Ab}}=0.290\\pm 0.018\\,{M}_{\\odot }$$. Comparing to theoretical isochrones, we find good agreement for the measured masses and JHK band magnitudes of the two components consistent with the age of the β Pic moving group. We derive a model-dependent age for the β Pic moving group of 26 ± 3 Myr by combining our results for V343 Normae with literature measurements for GJ 3305, which is another group member with resolved binary components and dynamical masses.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kim, Minjin; Ho, Luis C.; Im, Myungshin
2017-08-01
The Seyfert 2 galaxy NGC 5252 contains a recently identified ultra-luminous X-ray (ULX) source that has been suggested to be a possible candidate off-nuclear low-mass active galactic nucleus. We present follow-up optical integral-field unit observations obtained using Gemini Multi-Object Spectrographs on the Gemini-North telescope. In addition to confirming that the ionized gas in the vicinity of the ULX is kinematically associated with NGC 5252, the new observations reveal ordered motions consistent with rotation around the ULX. The close coincidence of the excitation source of the line-emitting gas with the position of the ULX further suggests that ULX itself is directlymore » responsible for the ionization of the gas. The spatially resolved measurements of [N ii] λ 6584/H α surrounding the ULX indicate a low gas-phase metallicity, consistent with those of other known low-mass active galaxies but not that of its more massive host galaxy. These findings strengthen the proposition that the ULX is not a background source but rather that it is the nucleus of a small, low-mass galaxy accreted by NGC 5252.« less
Nielsen, Eric L.; De Rosa, Robert J.; Wang, Jason; ...
2016-11-22
Here, we present new spatially resolved astrometry and photometry from the Gemini Planet Imager of the inner binary of the young multiple star system V343 Normae, which is a member of the β Pictoris (β Pic) moving group. V343 Normae comprises a K0 and mid-M star in a ~4.5 year orbit (AaAb) and a wide 10'' M5 companion (B). By combining these data with archival astrometry and radial velocities we fit the orbit and measure individual masses for both components ofmore » $${M}_{\\mathrm{Aa}}=1.10\\pm 0.10\\,{M}_{\\odot }$$ and $${M}_{\\mathrm{Ab}}=0.290\\pm 0.018\\,{M}_{\\odot }$$. Comparing to theoretical isochrones, we find good agreement for the measured masses and JHK band magnitudes of the two components consistent with the age of the β Pic moving group. We derive a model-dependent age for the β Pic moving group of 26 ± 3 Myr by combining our results for V343 Normae with literature measurements for GJ 3305, which is another group member with resolved binary components and dynamical masses.« less
NASA Technical Reports Server (NTRS)
Scott, Nic J.; Howell, Steve; Horch, Elliott
2016-01-01
Speckle imaging allows telescopes to achieve di raction limited imaging performance. The technique requires cameras capable of reading out frames at a very fast rate, e ectively `freezing out' atmospheric seeing. The resulting speckles can be correlated and images reconstructed that are at the di raction limit of the telescope. These new instruments are based on the successful performance and design of the Di erential Speckle Survey Instrument (DSSI) [2, 1]. The instruments are being built for the Gemini-N and WIYN telescopes and will be made available to the community via the peer review proposal process. We envision their primary use to be validation and characterization of exoplanet targets from the NASA K2 and TESS missions and RV discovered exoplanets. Such targets will provide excellent follow-up candidates for both the WIYN and Gemini telescopes [3]. Examples of DSSI data are shown in the gures below. We expect similar data quality in speckle imaging mode with the new instruments. Additionally, both cameras will have a wide- eld mode and standard SDSS lters. They will be highly versatile instruments and it is that likely many other science programs will request time on the cameras. The limiting magnitude for speckle observations, will remain around 13-14th at WIYN and 16-17th at Gemini, while wide- eld, normal CCD imaging operation should be able to go to much fainter, providing usual CCD imaging and photometric capabilities. The instruments will also have high utility as scoring cameras for telescope engineering purposes, or other applications where high time resolution is needed. Instrument support will be provided, including a software pipeline that takes raw speckle data to fully reconstructed images.
Hokupa'a-Gemini Discovery of Two Ultracool Companions to the Young Star HD 130948
NASA Astrophysics Data System (ADS)
Potter, D.; Martín, E. L.; Cushing, M. C.; Baudoz, P.; Brandner, W.; Guyon, O.; Neuhäuser, R.
2002-03-01
We report the discovery of two faint ultracool companions to the nearby (d~17.9 pc) young G2 V star HD 130948 (HR 5534, HIP 72567) using the Hokupa'a adaptive optics (AO) instrument mounted on the Gemini North 8 m telescope. Both objects have the same common proper motion as the primary star as seen over a 7 month baseline and have near-IR photometric colors that are consistent with an early L classification. Near-IR spectra taken with the NIRSPEC AO instrument on the Keck II telescope reveal K I lines, FeH, and H2O band heads. Based on these spectra, we determine that both objects have a spectral type of dL2 with an uncertainty of two spectral subclasses. The position of the new companions on the H-R diagram in comparison with theoretical models is consistent with the young age of the primary star (<0.8 Gyr) estimated on the basis of X-ray activity, lithium abundance, and fast rotation. HD 130948B and C likely constitute a pair of young contracting brown dwarfs with an orbital period of about 10 yr and will yield dynamical masses for L dwarfs in the near future. Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (US), the Particle Physics and Astronomy Research Council (UK), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), CNPq (Brazil), and CONICET (Argentina).
Long-term Efficacy of Vedolizumab for Ulcerative Colitis.
Loftus, Edward V; Colombel, Jean-Frédéric; Feagan, Brian G; Vermeire, Severine; Sandborn, William J; Sands, Bruce E; Danese, Silvio; D'Haens, Geert R; Kaser, Arthur; Panaccione, Remo; Rubin, David T; Shafran, Ira; McAuliffe, Megan; Kaviya, Arpeat; Sankoh, Serap; Mody, Reema; Abhyankar, Brihad; Smyth, Michael
2017-04-01
The GEMINI long-term safety [LTS] study is a continuing phase 3 trial investigating the safety and efficacy of vedolizumab, an α4β7 integrin antagonist for ulcerative colitis [UC] and Crohn's disease. We provide an interim analysis of efficacy in patients with UC. Patients from the C13004 and GEMINI 1 studies and a cohort of vedolizumab-naïve patients received open-label vedolizumab every 4 weeks. Interim data were collected from May 22, 2009 to June 27, 2013. Clinical response and remission, evaluated using partial Mayo scores, and health-related quality of life [HRQL] were assessed for up to 152 weeks of cumulative treatment in the efficacy population. As of June 27, 2013, 63% of the efficacy population [n = 532/845] were continuing treatment. Among patients who responded to vedolizumab induction and had data available, 88% [n = 120/136] were in remission after 104 weeks of exposure (96% [n = 70/73] after 152 weeks). Among patients who withdrew from every-8-week vedolizumab maintenance in GEMINI 1 [n = 32] before week 52, increased dosing to every 4 weeks in GEMINI LTS resulted in response and remission rates of 41% and 28%, respectively, after 52 weeks, an increase from 19% and 6%, respectively, from before the dose increase. Similar benefits were demonstrated regardless of prior tumour necrosis factor-antagonist exposure. Durable benefits on HRQL were also observed. Patients with UC experienced clinical and HRQL improvements with continued vedolizumab treatment. Increased dosing frequency to every 4 weeks was beneficial in patients who had loss of response to 8-weekly dosing. Copyright © 2016 European Crohn’s and Colitis Organisation (ECCO). Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com
Unveiling Uranus' Clouds: New Observations From Gemini-North NIFS And NIRI
NASA Astrophysics Data System (ADS)
Irwin, Patrick G. J.; Teanby, N. A.; Davis, G. R.; Fletcher, L. N.; Orton, G.; Tice, D.
2010-10-01
Observations of Uranus were made in September 2009 with the Gemini-North telescope in Hawaii, using both the NIFS and NIRI instruments. Adaptive optics were used to achieve a spatial resolution of approximately 0.1 arcsec. NIRI images were recorded with three spectral filters to constrain the overall appearance of the planet: J, H-continuum and CH4(long), and long slit spectra (1.49 to 1.79 microns) were obtained with the slit aligned on Uranus’ central meridian. In addition, the NIFS instrument was used to acquire spectra from other points on the planet, stepping the NIFS 3 x 3 arcsec field of view across Uranus’ disc. These observations were combined to yield complete images of Uranus at 2040 wavelengths between 1.476 and 1.803 microns with a spectral resolution of 5000. The observed spectra along Uranus central meridian were analyzed with the NEMESIS retrieval tool and used to infer the vertical/latitudinal variation in cloud optical depth. We find that the 2009 Gemini data perfectly complement our observations/conclusions from UKIRT/UIST observations made in 2006-2008 and show that the north polar zone at 45N has continued to steadily brighten while that at 45S has continued to fade. The improved spatial resolution of the Gemini observations compared with the non-AO UKIRT/UIST data remove many of the earlier ambiguities inherent in the previous analysis. Overall, Uranus appeared to be less convectively active in 2009 than in the previous 3 years, which suggests that now the equinox (which occurred in 2007) is over the atmosphere is settling back into the quiescent state seen by Voyager 2 in 1986. However, one discrete cloud was captured in the NIFS observations and was estimated to lie at a pressure level of 300-400 mbar.
NASA Astrophysics Data System (ADS)
Schirmer, Mischa; Garrel, Vincent; Sivo, Gaetano; Marin, Eduardo; Carrasco, Eleazar R.
2017-11-01
Multi-conjugated adaptive optics (MCAO) yield nearly diffraction-limited images at 2 μm wavelengths. Currently, Gemini Multi-Conjugate Adaptive Optics System (GeMS)/Gemini South Adaptive Optics Imager (GSAOI) at Gemini South is the only MCAO facility instrument at an 8-m telescope. Using real data, and for the first time, we investigate the gain in depth and signal-to-noise ratios (S/N) when MCAO is employed for Ks-band observations of distant galaxies. Our analysis is based on the Frontier Fields cluster MACS J0416.1-2403, observed with GeMS/GSAOI (near diffraction-limited) and compared against Very Large Telescope/HAWK-I (natural seeing) data. Using galaxy number counts, we show that the substantially increased thermal background and lower optical throughput of the MCAO unit are fully compensated for by the wavefront correction because the galaxy images can be measured in smaller apertures with less sky noise. We also performed a direct comparison of the S/N of sources detected in both data sets. For objects with intrinsic angular sizes corresponding to half the HAWK-I image seeing, the gain in S/N is 40 per cent. Even smaller objects experience a boost in S/N by up to a factor of 2.5 despite our suboptimal natural guide star configuration. The depth of the near diffraction limited images is more difficult to quantify than that of seeing limited images, due to a strong dependence on the intrinsic source profiles. Our results emphasize the importance of cooled MCAO systems for Ks-band observations with future, extremely large telescopes.
Al-Dulaymi, M; El-Aneed, A
2017-06-01
Diquaternary ammonium gemini surfactants have emerged as effective gene delivery vectors. A novel series of 11 peptide-modified compounds was synthesized, showing promising results in delivering genetic materials. The purpose of this work is to elucidate the tandem mass spectrometric (MS/MS) dissociation behavior of these novel molecules establishing a generalized MS/MS fingerprint. Exact mass measurements were achieved using a hybrid quadrupole orthogonal time-of-flight mass spectrometer, and a multi-stage MS/MS analysis was conducted using a triple quadrupole-linear ion trap mass spectrometer. Both instruments were operated in the positive ionization mode and are equipped with electrospray ionization. Abundant triply charged [M+H] 3+ species were observed in the single-stage analysis of all the evaluated compounds with mass accuracies of less than 8 ppm in mass error. MS/MS analysis showed that the evaluated gemini surfactants exhibited peptide-related dissociation characteristics because of the presence of amino acids within the compounds' spacer region. In particular, diagnostic product ions were originated from the neutral loss of ammonia from the amino acids' side chain resulting in the formation of pipecolic acid at the N-terminus part of the gemini surfactants. In addition, a charge-directed amide bond cleavage was initiated by the amino acids' side chain producing a protonated α-amino-ε-caprolactam ion and its complimentary C-terminus ion that contains quaternary amines. MS/MS and MS 3 analysis revealed common fragmentation behavior among all tested compounds, resulting in the production of a universal MS/MS fragmentation pathway. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.
NASA Technical Reports Server (NTRS)
Maisel, J. E.
1984-01-01
A historical overview of electrical power systems used in the U.S. manned spacecraft and some of the U.S. unmanned spacecraft is presented in this investigation. A time frame of approximately 25 years, the period for 1959 to 1984, is covered in this report. Results indicate that the nominal bus voltage was 28 volts dc in most spacecraft and all other voltage levels were derived from this voltage through such techniques as voltage inversion or rectification, or a combination. Most spacecraft used solar arrays for the main source of power except for those spacecraft that had a relatively short flight duration, or deep spaceprobes that were designed for very long flight duration. Fuel cells were used on Gemini, Apollo, and Space Shuttle (short duration flights) while radioisotope thermoelectric generators were employed on the Pioneer, Jupiter/Saturn, Viking Lander, and Voyager spacecraft (long duration flights). The main dc bus voltage was unregulated on the manned spacecraft with voltage regulation provided at the user loads. A combination of regulated, semiregulated, and unregulated buses were used on the unmanned spacecraft depending on the type of load. For example, scientific instruments were usually connected to regulated buses while fans, relays, etc. were energized from an unregulated bus. Different forms of voltage regulation, such as shunt, buck/boot, and pulse-width modulated regulators, were used. This report includes a comprehensive bibliography on spacecraft electrical power systems for the space programs investigated.
Isospin diffusion in binary collisions of 32S+Ca,4840 and 32S+48Ti at 17.7 MeV/nucleon
NASA Astrophysics Data System (ADS)
Piantelli, S.; Valdré, S.; Barlini, S.; Casini, G.; Colonna, M.; Baiocco, G.; Bini, M.; Bruno, M.; Camaiani, A.; Carboni, S.; Cicerchia, M.; Cinausero, M.; D'Agostino, M.; Degerlier, M.; Fabris, D.; Gelli, N.; Gramegna, F.; Gruyer, D.; Kravchuk, V. L.; Mabiala, J.; Marchi, T.; Morelli, L.; Olmi, A.; Ottanelli, P.; Pasquali, G.; Pastore, G.
2017-09-01
The systems 32S+Ca,4840 and 32S+48Ti at 17.7 MeV/nucleon were investigated with the setup general array for fragment identification and for emitted light particles in dissipative collisions (GARFIELD) plus ring counter (RCo) at Laboratori Nazionali di Legnaro (LNL) of Istituto Nazionale di Fisica Nucleare (INFN). Fusion evaporation (FE), fusion fission (FF), and deep inelastic (DIC) events were identified, also through the comparison with the prediction of a transport model (stochastic mean field, SMF), coupled to GEMINI++ as an afterburner. This work mainly deals with the study of isospin transport phenomena in DIC events. In particular, the isospin diffusion is highlighted by comparing the average isotopic content of the quasiprojectile (QP) remnants observed when the target is the N =Z nucleus 40Ca and when it is the neutron-rich 48Ca. Also, the d /p and t /p ratios for particles forward emitted with respect to the QP were found to increase with increasing N /Z of the target.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Woodley, Kristin A.; Harris, William E.; Puzia, Thomas H.
2010-01-10
We present new integrated light spectroscopy of globular clusters (GCs) in NGC 5128, a nearby giant elliptical galaxy less than 4 Mpc away, in order to measure radial velocities and derive ages, metallicities, and alpha-element abundance ratios. Using the Gemini South 8 meter telescope with the instrument Gemini Multi-Object Spectrograph, we obtained spectroscopy in the range of approx3400-5700 A for 72 GCs with a signal-to-noise ratio greater than 30 A{sup -1}; and we have also discovered 35 new GCs within NGC 5128 from our radial velocity measurements. We measured and compared the Lick indices from Hdelta{sub A} through Fe5406 withmore » the single stellar population models of Thomas et al. in order to derive age, metallicity, and [alpha/Fe] values. We also measure Lick indices for 41 Milky Way GCs from Puzia et al. and Schiavon et al. with the same methodology for direct comparison. Our results show that 68% of the NGC 5128 GCs have old ages (>8 Gyr), 14% have intermediate ages (5-8 Gyr), and 18% have young ages (<5 Gyr). However, when we look at the metallicity of the GCs as a function of age, we find 92% of metal-poor GCs and 56% of metal-rich GCs in NGC 5128 have ages >8 Gyr, indicating that the majority of both metallicity subpopulations of GCs formed earlier, with a significant population of young and metal-rich GCs forming later. Our metallicity distribution function generated directly from spectroscopic Lick indices is clearly bimodal, as is the color distribution of the same set of GCs. Thus, the metallicity bimodality is real and not an artifact of the color to metallicity conversion. However, the metallicity distribution function obtained from comparison with the single stellar population models is consistent with a unimodal, bimodal, or multimodal shape. The [alpha/Fe] values are supersolar with a mean value of 0.14 +- 0.04, indicating a fast formation timescale. However, the GCs in NGC 5128 are not as [alpha/Fe] enhanced as the Milky Way GCs also examined in this study. Our measured indices also indicate that the GCs in NGC 5128 may have a slight overabundance in nitrogen and a wider range of calcium strength compared to the Milky Way GCs. Our results support a rapid, early formation of the GC system in NGC 5128, with subsequent major accretion and/or GC and star-forming events in more recent times.« less
NASA Astrophysics Data System (ADS)
Telles, Eduardo; Thuan, Trinh X.; Izotov, Yuri I.; Carrasco, Eleazar R.
2014-01-01
Aims: We present an integral field spectroscopic study with the Gemini Multi-Object Spectrograph (GMOS) of the unusual blue compact dwarf (BCD) galaxy Mrk 996. Methods: We show through velocity and dispersion maps, emission-line intensity and ratio maps, and by a new technique of electron density limit imaging that the ionization properties of different regions in Mrk 996 are correlated with their kinematic properties. Results: From the maps, we can spatially distinguish a very dense high-ionization zone with broad lines in the nuclear region, and a less dense low-ionization zone with narrow lines in the circumnuclear region. Four kinematically distinct systems of lines are identified in the integrated spectrum of Mrk 996, suggesting stellar wind outflows from a population of Wolf-Rayet (WR) stars in the nuclear region, superposed on an underlying rotation pattern. From the intensities of the blue and red bumps, we derive a population of ~473 late nitrogen (WNL) stars and ~98 early carbon (WCE) stars in the nucleus of Mrk 996, resulting in a high N(WR)/N(O+WR) of 0.19. We derive, for the outer narrow-line region, an oxygen abundance 12 + log (O/H) = 7.94 ± 0.30 (~0.2 Z⊙) by using the direct Te method derived from the detected narrow [O iii]λ4363 line. The nucleus of Mrk 996 is, however, nitrogen-enhanced by a factor of ~20, in agreement with previous CLOUDY modeling. This nitrogen enhancement is probably due to nitrogen-enriched WR ejecta, but also to enhanced nitrogen line emission in a high-density environment. Although we have made use here of two new methods - principal component analysis (PCA) tomography and a method for mapping low- and high-density clouds - to analyze our data, new methodology is needed to further exploit the wealth of information provided by integral field spectroscopy. Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the Science and Technology Facilities Council (United Kingdom), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), Ministério da Ciência e Tecnologia (Brazil), and SECYT (Argentina).Reduced and calibrated data cubes are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/561/A64
Towards feasible and effective predictive wavefront control for adaptive optics
DOE Office of Scientific and Technical Information (OSTI.GOV)
Poyneer, L A; Veran, J
We have recently proposed Predictive Fourier Control, a computationally efficient and adaptive algorithm for predictive wavefront control that assumes frozen flow turbulence. We summarize refinements to the state-space model that allow operation with arbitrary computational delays and reduce the computational cost of solving for new control. We present initial atmospheric characterization using observations with Gemini North's Altair AO system. These observations, taken over 1 year, indicate that frozen flow is exists, contains substantial power, and is strongly detected 94% of the time.
Heroes and Legends Ribbon Cutting Ceremony
2016-11-11
Members of the Merritt Island High School Army Reserve Officers' Training Corps (ROTC) present the colors during the grand opening of the Heroes and Legends attraction at the Kennedy Space Center Visitor Complex. The new facility includes the U.S. Astronaut Hall of Fame and looks back to the pioneering efforts of Mercury, Gemini and Apollo. It sets the stage by providing the background and context for space exploration and the legendary men and women who pioneered the nation's journey into space.
The Challenges of Developing a Food System for a Mars Mission
NASA Technical Reports Server (NTRS)
Perchonok, Michele
2008-01-01
This viewgraph presents a review of the development of food systems for the use during a Mars Mission. It review some of the food delivery systems developed for all of the NASA space programs from Mercury, Gemini, and Apollo, to the Space Shuttle, International Space Station. The goals and objectives of the program are to: provide an adequate food system and develop a safe food system, that is nutritious and acceptable to astronauts, and to provide a food system that efficiently balances vehicle resources.
Deep Broad-Band Infrared Nulling Using A Single-Mode Fiber Beam Combiner and Baseline Rotation
NASA Technical Reports Server (NTRS)
Mennesson, Bertrand; Haguenauer, P.; Serabyn, E.; Liewer, K.
2006-01-01
The basic advantage of single-mode fibers for deep nulling applications resides in their spatial filtering ability, and has now long been known. However, and as suggested more recently, a single-mode fiber can also be used for direct coherent recombination of spatially separated beams, i.e. in a 'multi-axial' nulling scheme. After the first successful demonstration of deep (<2e-6) visible LASER nulls using this technique (Haguenauer & Serabyn, Applied Optics 2006), we decided to work on an infrared extension for ground based astronomical observations, e.g. using two or more off-axis sub-apertures of a large ground based telescope. In preparation for such a system, we built and tested a laboratory infrared fiber nuller working in a wavelength regime where atmospheric turbulence can be efficiently corrected, over a pass band (approx.1.5 to 1.8 micron) broad enough to provide reasonable sensitivity. In addition, since no snapshot images are readily accessible with a (single) fiber nuller, we also tested baseline rotation as an approach to detect off-axis companions while keeping a central null. This modulation technique is identical to the baseline rotation envisioned for the TPF-I space mission. Within this context, we report here on early laboratory results showing deep stable broad-band dual polarization infrared nulls <5e-4 (currently limited by detector noise), and visible LASER nulls better than 3e-4 over a 360 degree rotation of the baseline. While further work will take place in the laboratory to achieve deeper stable broad-band nulls and test off-axis sources detection through rotation, the emphasis will be put on bringing such a system to a telescope as soon as possible. Detection capability at the 500:1 contrast ratio in the K band (2.2 microns) seem readily accessible within 50-100 mas of the optical axis, even with a first generation system mounted on a >5m AO equipped telescope such as the Palomar Hale 200 inch, the Keck, Subaru or Gemini telescopes.
NASA Technical Reports Server (NTRS)
Wooden, Diane H.; Harker, David E.; Woodward, Charles E.
2006-01-01
When the Deep Impact Mission hit Jupiter Family comet 9P/Tempel 1, an ejecta crater was formed and an pocket of volatile gases and ices from 10-30 m below the surface was exposed (A Hearn et aI. 2005). This resulted in a gas geyser that persisted for a few hours (Sugita et al, 2005). The gas geyser pushed dust grains into the coma (Sugita et a1. 2005), as well as ice grains (Schulz et al. 2006). The smaller of the dust grains were submicron in radii (0-25.3 micron), and were primarily composed of highly refractory minerals including amorphous (non-graphitic) carbon, and silicate minerals including amorphous (disordered) olivine (Fe,Mg)2SiO4 and pyroxene (Fe,Mg)SiO3 and crystalline Mg-rich olivine. The smaller grains moved faster, as expected from the size-dependent velocity law produced by gas-drag on grains. The mineralogy evolved with time: progressively larger grains persisted in the near nuclear region, having been imparted with slower velocities, and the mineralogies of these larger grains appeared simpler and without crystals. The smaller 0.2-0.3 micron grains reached the coma in about 1.5 hours (1 arc sec = 740 km), were more diverse in mineralogy than the larger grains and contained crystals, and appeared to travel through the coma together. No smaller grains appeared at larger coma distances later (with slower velocities), implying that if grain fragmentation occurred, it happened within the gas acceleration zone. These results of the high spatial resolution spectroscopy (GEMINI+Michelle: Harker et 4. 2005, 2006; Subaru+COMICS: Sugita et al. 2005) revealed that the grains released from the interior were different from the nominally active areas of this comet by their: (a) crystalline content, (b) smaller size, (c) more diverse mineralogy. The temporal changes in the spectra, recorded by GEMIM+Michelle every 7 minutes, indicated that the dust mineralogy is inhomogeneous and, unexpectedly, the portion of the size distribution dominated by smaller grains has a more diverse mineralogy. The lower spatial resolution, high sensitivity Spitzer IRS data reveal resonances of refractory minerals (those seen by GEMINI+Michelle plus ortho-pyroxene)) as well resonances that can be attributed to phillosilicates (layer lattice silicates such as Montmorillonite) (Lisse et al. 2006). Pre- and post-impact, micron to submicron grains were deciphered to be present in the coma by the modeling the high spatial resolution images to account for nucleus plus inner coma fluxes (Wooden et al. 2005, 2006; Harker et al. 2005, 2006a). Note also that crystalline silicates were released from the interior of 73P-B/SW-3 as it disintegrated (Harker et al. 2006b). From the Deep Impact and the disintegration of 73P-B, we are led to ask the questians: Why is the mineralogy of the dust released from a volatile-rich pocket beneath the surface different from the dust that is released from the nominally active areas? Could the most volatile pockets be exhausted quickly? Why would crystalline silicates be associated with more volatile materials? Perhaps the structure of the comet is so inhomogeneous, e.g., the layered pile mode2 of the nucleus (Belton et al. 2006), that a reservoir of crystalline silicate and submicron grains just happens to not be released by the nominally active areas of comet 9P? Perhaps comets lose matter through their mantles from below their surfaces, thus preserving ancient topographic structures and radiation damaged silicates and carbon? We will discuss and ponder different scenarios. We will discuss future directions for coordinated observations of JF comets.
GEMINI-TITAN (GT)-10 - MISC. - INFLIGHT (MILKY WAY) - OUTER SPACE
1966-08-01
S66-45314 (19 July 1966) --- Ultraviolet spectra of stars in the region of the Southern Cross. These objective-grating spectra were obtained by astronauts John W. Young and Michael Collins during Gemini-10 stand-up EVA on July 19, 1966, with a 70mm Maurer camera and its f/3.3 focal length lens. The spectra extends from 2,200 angstroms to about 4,000 angstroms. The spacecraft was docked to the horizon-stabilized Agena-10; thus giving an apparent field of rotation resulting from the four-degree-per-minute orbital motion during the 20-second exposure time. Photo credit: NASA
GEMINI-TITAN (GT)-10 - MISC. - INFLIGHT (MILKY WAY) - OUTER SPACE
1966-08-01
S66-45328 (19 July 1966) --- Ultraviolet spectra of stars in the Carina-Vela region of the southern Milky Way. These objective-grating spectra were obtained by astronauts John W. Young and Michael Collins during Gemini-10 stand-up EVA on July 19, 1966, with a 70mm Maurer camera and its f/3.3 focal length lens. The spectra extends from 2,200 angstroms to about 4,000 angstroms. The spacecraft was docked to the horizon-stabilized Agena-10; thus giving an apparent field of rotation resulting from the four-degree-per-minute orbital motion during the 20-second exposure time. Photo credit: NASA
Sharing the skies: the Gemini Observatory international time allocation process
NASA Astrophysics Data System (ADS)
Margheim, Steven J.
2016-07-01
Gemini Observatory serves a diverse community of four partner countries (United States, Canada, Brazil, and Argentina), two hosts (Chile and University of Hawaii), and limited-term partnerships (currently Australia and the Republic of Korea). Observing time is available via multiple opportunities including Large and Long Pro- grams, Fast-turnaround programs, and regular semester queue programs. The slate of programs for observation each semester must be created by merging programs from these multiple, conflicting sources. This paper de- scribes the time allocation process used to schedule the overall science program for the semester, with emphasis on the International Time Allocation Committee and the software applications used.
GEMINI-TITAN (GT)-11 - HIGH APOGEE - EARTH SKY
1966-09-14
S66-54530 --- Libyan Desert area of Sudan, foreground, and the United Arab Republic (Egypt), at lower left, as seen from the orbiting Gemini-11 spacecraft at an altitude of 300 nautical miles during its 27th revolution of Earth. In view is the Nile River from Biba in Egypt to Khartoum in the Sudan. The Red Sea is in the background. At upper left is the Arabian Peninsula. At top right is Ethiopia. Note L-band antenna of the Agena Target Vehicle. Taken with a modified 70mm Hasselblad camera, using Eastman Kodak, Ektachrome, MS (S.O. 368) color film. Photo credit: NASA
GEMINI-9 - EARTH SKY - NORTHWESTERN MEXICO, BAJA CALIFORNIA
1966-06-05
S66-38070 (5 June 1966) --- Northwestern Mexico as seen from the Gemini-9A spacecraft during its 32nd revolution of Earth. The large penisula is Baja California. The body of water at lower right is the Pacific Ocean. The land mass at upper left is the State of Sonora. The Gulf of California separates Sonora from the peninsula. The nose of the spacecraft is at left; and at right is the open hatch of the spacecraft. Astronaut Eugene A. Cernan, pilot, took this picture with his modified 70mm Hasselblad EVA camera, using Eastman Kodak, Ektachrome, MS (S.O. 217) color film. Photo credit: NASA
NASA Astrophysics Data System (ADS)
Hirst, Paul; Cardenes, Ricardo
2016-08-01
We have developed and deployed a new data archive for the Gemini Observatory. Focused on simplicity and ease of use, the archive provides a number of powerful and novel features including automatic association of calibration data with the science data, and the ability to bookmark searches. A simple but powerful API allows programmatic search and download of data. The archive is hosted on Amazon Web Services, which provides us excellent internet connectivity and significant cost savings in both operations and development over more traditional deployment options. The code is written in python, utilizing a PostgreSQL database and Apache web server.
1965-12-18
S65-61830 (18 Dec. 1965) --- Astronauts James A. Lovell Jr. (left), Gemini-7 pilot, and Frank Borman, command pilot, are shown just after they arrived aboard the aircraft carrier USS Wasp. Greeting the astronauts are Donald Stullken (at Lovell's right), Recovery Operations Branch, Landing and Recovery Division, Dr. Howard Minners (standing beside Borman), Flight Medicine Branch, Center Medical Office, Manned Spacecraft Center, and Bennett James (standing behind Borman), a NASA Public Affairs Officer. The National Aeronautics and Space Administration's Gemini-7 spacecraft splashed down in the western Atlantic recovery area at 9:05 a.m. (EST), Dec. 18, 1965, to conclude a record-breaking 14-day mission in space. Photo credit: NASA
NASA Technical Reports Server (NTRS)
Charles, John B.
2013-01-01
An attempt to clarify some vague memories of underwater studies of astronaut capabilities in space led Dr. John Charles to become acquainted with Sam Mattingly, one of the pioneers in the field, and to greater insights into Mattingly's work simulating Gemini EVAs in the mid-1960s. Charles recounted major accomplishments by Environmental Research Associates (ERA), Mattingly's company for contracting with NASA Langley on several early studies. ERA's work was considered within the context of contemporary efforts to simulate weightlessness and the widespread development of neutral buoyancy facilities after ERA's successful demonstration for Gemini 12.
Bioassay of body fluids, experiment M005
NASA Technical Reports Server (NTRS)
Dietlein, L. F.; Harris, E. S.
1971-01-01
Preflight and postflight urine and plasma samples from the Gemini 7 and Gemini 9 crewmembers were analyzed. Electrolyte and water retention observed immediately postflight was consistent with the assumption that the Gauer-Henry atrial reflex was responsive to a change from the weightless to the unit-gravity environment. Immediately postflight, plasma 17-hydroxycorticosteroid concentrations were increased and plasma uric acid concentration was decreased. The increased excretion of 17-hydroxycorticosteroids immediately postflight probably was caused by the stress of entry. The postflight increase of plasma protein, and the slightly smaller increase of plasma electrolytes postflight, was consistent with an inflight water and electrolyte loss that resulted in postflight retention of water and electrolytes.
Tumbling and spaceflight: the Gemini VIII experience.
Mohler, S R; Nicogossian, A E; McCormack, P D; Mohler, S R
1990-01-01
A malfunctioning orbital flight attitude thruster during the flight of Gemini VIII led to acceleration forces on astronauts Neil Armstrong (commander) and David Scott (pilot) that created the potential for derogation of oculo-vestibular and eye-hand coordination effects. The spacecraft attained an axial tumbling rotation of 50 rpm and would have exceeded this had not the commander accurately diagnosed the problem and taken immediate corrective action. By the time counter-measure controls were applied, both astronauts were experiencing vertigo and the physiological effects of the tumbling acceleration. Data from the recorders reveal that one astronaut experienced -Gy of 0.92 G-units, and the other +Gy of 0.92 for approximately 46 s. Both received a -Gz of 0.89 G-units from the waist up with a +Gz of 0.05 from the waist down. A substantial increase of time and/or an increase in rpm would ultimately have produced incapacitation of both astronauts. NASA corrected the Gemini thruster problem by changing the ignition system wiring. Future space-craft undertaking long-term missions could be equipped with unambiguous thruster fault displays and could have computer-controlled automatic cutoffs to control excessive thruster burns.
GEMINI SPECTROSCOPY OF ULTRACOMPACT DWARFS IN THE FOSSIL GROUP NGC 1132
DOE Office of Scientific and Technical Information (OSTI.GOV)
Madrid, Juan P.; Donzelli, Carlos J.
2013-06-20
A spectroscopic follow-up of ultracompact dwarf (UCD) candidates in the fossil group NGC 1132 is undertaken with the Gemini Multi Object Spectrograph. These new Gemini spectra prove the presence of six UCDs in the fossil group NGC 1132 at a distance of D {approx} 100 Mpc and a recessional velocity of v{sub r} = 6935 {+-} 11 km s{sup -1}. The brightest and largest member of the UCD population is an M32 analog with a size of 77.1 pc and a magnitude of M{sub V} = -14.8 mag with the characteristics in between those of the brightest UCDs and compactmore » elliptical galaxies. The ensemble of UCDs have an average radial velocity of (v{sub r} ) = 6966 {+-} 208 km s{sup -1} and a velocity dispersion of {sigma}{sub v} = 169 {+-} 18 km s{sup -1} similar to the one of poor galaxy groups. This work shows that UCDs can be used as test particles to determine the dynamical properties of galaxy groups. The presence of UCDs in the fossil group environment is confirmed and thus the fact that UCDs can form across diverse evolutionary conditions.« less
NASA Astrophysics Data System (ADS)
Geng, Xiang F.; Hu, Xing Q.; Xia, Ji J.; Jia, Xue C.
2013-04-01
A series of novel di-hydroxyl-sulfate-betaine-type zwitterionic gemini surfactants of 1,2-bis[N-ethyl-N-(2-hydroxyl-3-sulfopropyl)-alkylammonium] alkyl betaines (DBAs-n, where s and n represent the spacer length of 2, 4 and 6 and the hydrocarbon chain length of 8, 12, 14, 16 and 18, respectively) were synthesized by reacting alkylamine with sodium 3-chloro-2-hydroxypropanesulfonate (the alternative sulphonated agent), followed by the reactions with а,ω-dibromoalkyl and then ethyl bromide. Their adsorption and aggregation properties were investigated by means of equilibrium surface tension, dynamic light-scattering (DLS) and transmission electron microscopy (TEM). DBAs-n gemini surfactants showed excellent surface activities and packed tightly at the interface. For example, the minimum CMC value for DBAs-n series was of the order of 10-5 M and the surface tension of water can be decreased as low as 22.2 mN/m. It was also found that the aggregates of DBAs-n solutions were significantly dependent on their hydrocarbon chain lengths. The aggregates changed from vesicles to entangled fiber-like micelles as the chain length increased from dodecyl to tetradecyl.
Bhat, Waseem Feeroze; Bhat, Imtiyaz Ahmad; Bhat, Sheraz Ahmad; Bano, Bilqees
2016-12-01
Many protein misfolding diseases in mammalian system are characterised by the accumulation of protein aggregates in amyloid fibrillar forms. Several therapeutic approaches include reduction in the production of the amyloidogenic form of proteins, increase in the clearance rate of misfolded or aggregated proteins, and direct inhibition of the self-assembly process have been explained. One of the possible remedial treatments for such disorders may be to identify molecules which are capable of either preventing formation of fibrils or disintegrating the formed fibrils. In this work, we have studied the effect of conventional surfactants; sodium dodecylsulphate (SDS), cetyl trimethylammonium bromide (CTAB) and dicationic gemini (16-4-16) surfactant on the disintegration of the goat brain cystatin (GBC) fibrils above their critical micelle concentrations (CMC) using ThT fluorescence, CD, TEM, Congo red and turbidity approaches. The results obtained are significant and showing the best disintegrating potency on GBC fibrils with gemini surfactant. The outcome from this work will aid in the development and/or design of potential inhibitory agents against amyloid deposits associated with amyloid diseases. Copyright © 2016 Elsevier B.V. All rights reserved.
GEMINI/GeMS Observations Unveil the Structure of the Heavily Obscured Globular Cluster Liller 1.
NASA Astrophysics Data System (ADS)
Saracino, S.; Dalessandro, E.; Ferraro, F. R.; Lanzoni, B.; Geisler, D.; Mauro, F.; Villanova, S.; Moni Bidin, C.; Miocchi, P.; Massari, D.
2015-06-01
By exploiting the exceptional high-resolution capabilities of the near-IR camera GSAOI combined with the Gemini Multi-Conjugate Adaptive System at the GEMINI South Telescope, we investigated the structural and physical properties of the heavily obscured globular cluster Liller 1 in the Galactic bulge. We have obtained the deepest and most accurate color-magnitude diagram published so far for this cluster, reaching {{K}s}˜ 19 (below the main-sequence turnoff level). We used these data to redetermine the center of gravity of the system, finding that it is located about 2.″2 southeast from the literature value. We also built new star density and surface brightness profiles for the cluster and rederived its main structural and physical parameters (scale radii, concentration parameter, central mass density, total mass). We find that Liller 1 is significantly less concentrated (concentration parameter c=1.74) and less extended (tidal radius {{r}t}=298\\prime\\prime and core radius {{r}c}=5\\buildrel{\\prime\\prime}\\over{.} 39) than previously thought. By using these newly determined structural parameters, we estimated the mass of Liller 1 to be {{M}tot}=2.3+0.3-0.1× {{10}6} {{M}⊙ } ({{M}tot}=1.5+0.2-0.1× {{10}6} {{M}⊙ } for a Kroupa initial mass function), which is comparable to that of the most massive clusters in the Galaxy (ω Centari and Terzan 5). Also, Liller 1 has the second-highest collision rate (after Terzan 5) among all star clusters in the Galaxy, thus confirming that it is an ideal environment for the formation of collisional objects (such as millisecond pulsars). Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), Ministério da Ciência, Tecnologia e Inovação (Brazil), and Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina). Based on observations gathered with the ESO-VISTA telescope (program ID 179.B-2002).
Validation of a Monte Carlo simulation of the Philips Allegro/GEMINI PET systems using GATE
NASA Astrophysics Data System (ADS)
Lamare, F.; Turzo, A.; Bizais, Y.; Cheze LeRest, C.; Visvikis, D.
2006-02-01
A newly developed simulation toolkit, GATE (Geant4 Application for Tomographic Emission), was used to develop a Monte Carlo simulation of a fully three-dimensional (3D) clinical PET scanner. The Philips Allegro/GEMINI PET systems were simulated in order to (a) allow a detailed study of the parameters affecting the system's performance under various imaging conditions, (b) study the optimization and quantitative accuracy of emission acquisition protocols for dynamic and static imaging, and (c) further validate the potential of GATE for the simulation of clinical PET systems. A model of the detection system and its geometry was developed. The accuracy of the developed detection model was tested through the comparison of simulated and measured results obtained with the Allegro/GEMINI systems for a number of NEMA NU2-2001 performance protocols including spatial resolution, sensitivity and scatter fraction. In addition, an approximate model of the system's dead time at the level of detected single events and coincidences was developed in an attempt to simulate the count rate related performance characteristics of the scanner. The developed dead-time model was assessed under different imaging conditions using the count rate loss and noise equivalent count rates performance protocols of standard and modified NEMA NU2-2001 (whole body imaging conditions) and NEMA NU2-1994 (brain imaging conditions) comparing simulated with experimental measurements obtained with the Allegro/GEMINI PET systems. Finally, a reconstructed image quality protocol was used to assess the overall performance of the developed model. An agreement of <3% was obtained in scatter fraction, with a difference between 4% and 10% in the true and random coincidence count rates respectively, throughout a range of activity concentrations and under various imaging conditions, resulting in <8% differences between simulated and measured noise equivalent count rates performance. Finally, the image quality validation study revealed a good agreement in signal-to-noise ratio and contrast recovery coefficients for a number of different volume spheres and two different (clinical level based) tumour-to-background ratios. In conclusion, these results support the accurate modelling of the Philips Allegro/GEMINI PET systems using GATE in combination with a dead-time model for the signal flow description, which leads to an agreement of <10% in coincidence count rates under different imaging conditions and clinically relevant activity concentration levels.
Improving signal-to-noise in the direct imaging of exoplanets and circumstellar disks with MLOCI
NASA Astrophysics Data System (ADS)
Wahhaj, Zahed; Cieza, Lucas A.; Mawet, Dimitri; Yang, Bin; Canovas, Hector; de Boer, Jozua; Casassus, Simon; Ménard, François; Schreiber, Matthias R.; Liu, Michael C.; Biller, Beth A.; Nielsen, Eric L.; Hayward, Thomas L.
2015-09-01
We present a new algorithm designed to improve the signal-to-noise ratio (S/N) of point and extended source detections around bright stars in direct imaging data.One of our innovations is that we insert simulated point sources into the science images, which we then try to recover with maximum S/N. This improves the S/N of real point sources elsewhere in the field. The algorithm, based on the locally optimized combination of images (LOCI) method, is called Matched LOCI or MLOCI. We show with Gemini Planet Imager (GPI) data on HD 135344 B and Near-Infrared Coronagraphic Imager (NICI) data on several stars that the new algorithm can improve the S/N of point source detections by 30-400% over past methods. We also find no increase in false detections rates. No prior knowledge of candidate companion locations is required to use MLOCI. On the other hand, while non-blind applications may yield linear combinations of science images that seem to increase the S/N of true sources by a factor >2, they can also yield false detections at high rates. This is a potential pitfall when trying to confirm marginal detections or to redetect point sources found in previous epochs. These findings are relevant to any method where the coefficients of the linear combination are considered tunable, e.g., LOCI and principal component analysis (PCA). Thus we recommend that false detection rates be analyzed when using these techniques. Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (USA), the Science and Technology Facilities Council (UK), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), Ministério da Ciência e Tecnologia (Brazil) and Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina).
NASA Astrophysics Data System (ADS)
Salinas, R.; Alabi, A.; Richtler, T.; Lane, R. R.
2015-05-01
As tracers of star formation, galaxy assembly, and mass distribution, globular clusters have provided important clues to our understanding of early-type galaxies. But their study has been mostly constrained to galaxy groups and clusters where early-type galaxies dominate, leaving the properties of the globular cluster systems (GCSs) of isolated ellipticals as a mostly uncharted territory. We present Gemini-South/GMOS g'i' observations of five isolated elliptical galaxies: NGC 3962, NGC 2865, IC 4889, NGC 2271, and NGC 4240. Photometry of their GCSs reveals clear color bimodality in three of them, but remains inconclusive for the other two. All the studied GCSs are rather poor with a mean specific frequency SN ~ 1.5, independently of the parent galaxy luminosity. Considering information from previous work as well, it is clear that bimodality and especially the presence of a significant, even dominant, population of blue clusters occurs at even the most isolated systems, which casts doubts on a possible accreted origin of metal-poor clusters, as suggested by some models. Additionally, we discuss the possible existence of ultra-compact dwarfs around the isolated elliptical NGC 3962. Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the Science and Technology Facilities Council (United Kingdom), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), Ministério da Ciência, Tecnologia e Inovação (Brazil) and Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina).Globular cluster photometry is available in electronic form at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/577/A59Appendices are available in electronic form at http://www.aanda.org
Management aspects of Gemini's base facility operations project
NASA Astrophysics Data System (ADS)
Arriagada, Gustavo; Nitta, Atsuko; Adamson, A. J.; Nunez, Arturo; Serio, Andrew; Cordova, Martin
2016-08-01
Gemini's Base Facilities Operations (BFO) Project provided the capabilities to perform routine nighttime operations without anyone on the summit. The expected benefits were to achieve money savings and to become an enabler of the future development of remote operations. The project was executed using a tailored version of Prince2 project management methodology. It was schedule driven and managing it demanded flexibility and creativity to produce what was needed, taking into consideration all the constraints present at the time: Time available to implement BFO at Gemini North (GN), two years. The project had to be done in a matrix resources environment. There were only three resources assigned exclusively to BFO. The implementation of new capabilities had to be done without disrupting operations. And we needed to succeed, introducing the new operational model that implied Telescope and instrumentation Operators (Science Operations Specialists - SOS) relying on technology to assess summit conditions. To meet schedule we created a large number of concurrent smaller projects called Work Packages (WP). To be reassured that we would successfully implement BFO, we initially spent a good portion of time and effort, collecting and learning about user's needs. This was done through close interaction with SOSs, Observers, Engineers and Technicians. Once we had a clear understanding of the requirements, we took the approach of implementing the "bare minimum" necessary technology that would meet them and that would be maintainable in the long term. Another key element was the introduction of the "gradual descent" concept. In this, we increasingly provided tools to the SOSs and Observers to prevent them from going outside the control room during nighttime operations, giving them the opportunity of familiarizing themselves with the new tools over a time span of several months. Also, by using these tools at an early stage, Engineers and Technicians had more time for debugging, problem fixing and systems usage and servicing training as well.