Development of the super high angular resolution principle for X-ray imaging

International Nuclear Information System (INIS)

Zhang Chen; Zhang Shuangnan

2011-01-01

Development of the Super High Angular Resolution Principle (SHARP) for coded-mask X-ray imaging is presented. We prove that SHARP can be considered as a generalized coded mask imaging method with a coding pattern comprised of diffraction-interference fringes in the mask pattern. The angular resolution of SHARP can be improved by detecting the fringes more precisely than the mask's element size, i.e. by using a detector with a pixel size smaller than the mask's element size. The proposed mission SHARP-X for solar X-ray observations is also briefly discussed. (research papers)

A hard x-ray spectrometer for high angular resolution observations of cosmic sources

International Nuclear Information System (INIS)

Hailey, C.J.; Ziock, K.P.; Harrison, F.; Kahn, S.M.; Liedahl, D.; Lubin, P.M.; Seiffert, M.

1988-01-01

LAXRIS (large area x-ray imaging spectrometer) is an experimental, balloon-borne, hard x-ray telescope that consists of a coaligned array of x-ray imaging spectrometer modules capable of obtaining high angular resolution (1--3 arcminutes) with moderate energy resolution in the 20- to 300-keV region. Each spectrometer module consists of a CsI(Na) crystal coupled to a position-sensitive phototube with a crossed-wire, resistive readout. Imaging is provided by a coded aperture mask with a 4-m focal length. The high angular resolution is coupled with rather large area (/approximately/800 cm 2 ) to provide good sensitivity. Results are presented on performance and overall design. Sensitivity estimates are derived from a Monte-Carlo code developed to model the LAXRIS response to background encountered at balloon altitudes. We discuss a variety of observations made feasible by high angular resolution. For instance, spatially resolving the nonthermal x-ray emission from clusters of galaxies is suggested as an ideal program for LAXRIS. 15 refs., 5 figs

A two-dimensional wide-angle proton spectrometer with improved angular resolution

International Nuclear Information System (INIS)

Yang, Su; Deng, Yanqing; Ge, Xulei; Fang, Yuan; Wei, Wenqing; Gao, Jian; Liu, Feng; Chen, Min; Liao, Guoqian; Li, Yutong; Zhao, Li; Ma, Yanyun

2017-01-01

We present an improvement design of a two-dimensional (2D) angular-resolved proton spectrometer for wide-angle measurement of proton beams from high-intensity laser-solid interactions. By using a 2D selective entrance pinhole array with different periods in orthogonal axes, the angular resolution along one dimension is improved by a factor of 6.7. This improvement provides the accessibility to detect the spatial fine structures of the proton energy spectrum.

A two-dimensional wide-angle proton spectrometer with improved angular resolution

Energy Technology Data Exchange (ETDEWEB)

Yang, Su [Key Laboratory for Laser Plasmas (Ministry of Education) and Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Collaborative Innovation Center of IFSA (CICIFSA), Shanghai Jiao Tong University, Shanghai 200240 (China); Deng, Yanqing [Key Laboratory for Laser Plasmas (Ministry of Education) and Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Collaborative Innovation Center of IFSA (CICIFSA), Shanghai Jiao Tong University, Shanghai 200240 (China); College of Science, National University of Defense Technology, Changsha 410073 (China); Ge, Xulei [Key Laboratory for Laser Plasmas (Ministry of Education) and Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Collaborative Innovation Center of IFSA (CICIFSA), Shanghai Jiao Tong University, Shanghai 200240 (China); State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433 (China); Fang, Yuan; Wei, Wenqing; Gao, Jian; Liu, Feng; Chen, Min [Key Laboratory for Laser Plasmas (Ministry of Education) and Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Collaborative Innovation Center of IFSA (CICIFSA), Shanghai Jiao Tong University, Shanghai 200240 (China); Liao, Guoqian; Li, Yutong [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Collaborative Innovation Center of IFSA (CICIFSA), Shanghai Jiao Tong University, Shanghai 200240 (China); Zhao, Li [State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433 (China); Ma, Yanyun [College of Science, National University of Defense Technology, Changsha 410073 (China); Collaborative Innovation Center of IFSA (CICIFSA), Shanghai Jiao Tong University, Shanghai 200240 (China); and others

2017-07-11

We present an improvement design of a two-dimensional (2D) angular-resolved proton spectrometer for wide-angle measurement of proton beams from high-intensity laser-solid interactions. By using a 2D selective entrance pinhole array with different periods in orthogonal axes, the angular resolution along one dimension is improved by a factor of 6.7. This improvement provides the accessibility to detect the spatial fine structures of the proton energy spectrum.

Ground-based gamma-ray astronomy with Cherenkov telescopes

International Nuclear Information System (INIS)

Hinton, Jim

2009-01-01

Very high-energy (>100 GeV) γ-ray astronomy is emerging as an important discipline in both high-energy astrophysics and astro-particle physics. This field is currently dominated by imaging atmospheric-Cherenkov telescopes (IACTs) and arrays of these telescopes. Such arrays have achieved the best angular resolution and energy flux sensitivity in the γ-ray domain and are still far from the fundamental limits of the technique. Here, I will summarize some key aspects of this technique and go on to review the current status of the major instruments and to highlight selected recent results.

γ-ray telescopes using conversions to e+e- pairs: event generators, angular resolution and polarimetry

Science.gov (United States)

Gros, P.; Bernard, D.

2017-02-01

We benchmark various available event generators in Geant4 and EGS5 in the light of ongoing projects for high angular-resolution pair-conversion telescopes at low energy. We compare the distributions of key kinematic variables extracted from the geometry of the three final state particles. We validate and use as reference an exact generator using the full 5D differential cross-section of the conversion process. We focus in particular on the effect of the unmeasured recoiling nucleus on the angular resolution. We show that for high resolution trackers, the choice of the generator affects the estimated resolution of the telescope. We also show that the current available generator are unable to describe accurately a linearly polarised photon source.

Compact and high-resolution optical orbital angular momentum sorter

Directory of Open Access Journals (Sweden)

Chenhao Wan

2017-03-01

Full Text Available A compact and high-resolution optical orbital angular momentum (OAM sorter is proposed and demonstrated. The sorter comprises a quadratic fan-out mapper and a dual-phase corrector positioned in the pupil plane and the Fourier plane, respectively. The optical system is greatly simplified compared to previous demonstrations of OAM sorting, and the performance in resolution and efficiency is maintained. A folded configuration is set up using a single reflective spatial light modulator (SLM to demonstrate the validity of the scheme. The two phase elements are implemented on the left and right halves of the SLM and connected by a right-angle prism. Experimental results demonstrate the high resolution of the compact OAM sorter, and the current limit in efficiency can be overcome by replacing with transmissive SLMs and removing the beam splitters. This novel scheme paves the way for the miniaturization and integration of high-resolution OAM sorters.

A 3D CZT high resolution detector for x- and gamma-ray astronomy

DEFF Research Database (Denmark)

Kuvvetli, Irfan; Budtz-Jørgensen, Carl; Zappettini, A.

2014-01-01

At DTU Space we have developed a high resolution three dimensional (3D) position sensitive CZT detector for high energy astronomy. The design of the 3D CZT detector is based on the CZT Drift Strip detector principle. The position determination perpendicular to the anode strips is performed using...

Understanding deformation with high angular resolution electron backscatter diffraction (HR-EBSD)

Science.gov (United States)

Britton, T. B.; Hickey, J. L. R.

2018-01-01

High angular resolution electron backscatter diffraction (HR-EBSD) affords an increase in angular resolution, as compared to ‘conventional’ Hough transform based EBSD, of two orders of magnitude, enabling measurements of relative misorientations of 1 x 10-4 rads (~ 0.006°) and changes in (deviatoric) lattice strain with a precision of 1 x 10-4. This is achieved through direct comparison of two or more diffraction patterns using sophisticated cross-correlation based image analysis routines. Image shifts between zone axes in the two-correlated diffraction pattern are measured with sub-pixel precision and this realises the ability to measure changes in interplanar angles and lattice orientation with a high degree of sensitivity. These shifts are linked to strains and lattice rotations through simple geometry. In this manuscript, we outline the basis of the technique and two case studies that highlight its potential to tackle real materials science challenges, such as deformation patterning in polycrystalline alloys.

Super-resolution and ultra-sensitivity of angular rotation measurement based on SU(1,1) interferometers using homodyne detection

Science.gov (United States)

Liu, Jun; Li, Shitao; Wei, Dong; Gao, Hong; Li, Fuli

2018-02-01

We theoretically explore the angular rotation measurement sensitivity of SU(1,1) interferometers with a coherent beam and a vacuum beam input by using orbital angular momentum (OAM). Compared with the OAM in an SU(2) interferometer, the SU(1,1) interferometer employing homodyne detection can further surpass the angular rotation shot noise limit \\tfrac{1}{2l\\sqrt{N}} and improve the resolution and sensitivity of angular rotation measurement. Two models are considered, one is that OAM is carried by a probe beam and the other one is a pump beam with the OAM. The sensitivity can be improved by higher OAM and nonlinear process with a large gain. The resolution can be enhanced in the case that the pump beam has OAM. Moreover, we present a brief discussion on the variation of resolution and sensitivity in the presence of photon loss.

Galactic Astronomy in the Ultraviolet

Science.gov (United States)

Rastorguev, A. S.; Sachkov, M. E.; Zabolotskikh, M. V.

2017-12-01

We propose a number of prospective observational programs for the ultraviolet space observatory WSO-UV, which seem to be of great importance to modern galactic astronomy. The programs include the search for binary Cepheids; the search and detailed photometric study and the analysis of radial distribution of UV-bright stars in globular clusters ("blue stragglers", blue horizontal-branch stars, RR Lyrae variables, white dwarfs, and stars with UV excesses); the investigation of stellar content and kinematics of young open clusters and associations; the study of spectral energy distribution in hot stars, including calculation of the extinction curves in the UV, optical and NIR; and accurate definition of the relations between the UV-colors and effective temperature. The high angular resolution of the observatory allows accurate astrometric measurements of stellar proper motions and their kinematic analysis.

Journal of Astrophysics and Astronomy | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Journal of Astrophysics and Astronomy. Samir Choudhuri. Articles written in Journal of Astrophysics and Astronomy. Volume 37 Issue 4 December 2016 pp 35 Review. Prospects of Measuring the Angular Power Spectrum of the Diffuse Galactic Synchrotron Emission with SKA1 Low · Sk. Saiyad Ali Somnath ...

Angular resolution in underground detectors and a status report of the Soudan II nucleon decay detector

International Nuclear Information System (INIS)

Ambats, I.; Ayres, D.; Barrett, W.

1987-01-01

This paper is a status report of the Soudan II honeycomb drift chamber project. It reports on the physics goals, present progress and future schedule of our experiment. It also includes a discussion of the angular resolution of cosmic ray muons which can be achieved in underground detectors, and in particular how to calibrate the resolution using the moon's shadow in cosmic rays. This last point has relevance in trying to understand the angular distributions in the reported observations of underground muons from Cygnus X-3. 12 refs., 9 figs

Q-ball imaging models: comparison between high and low angular resolution diffusion-weighted MRI protocols for investigation of brain white matter integrity

Energy Technology Data Exchange (ETDEWEB)

Caiazzo, Giuseppina; Trojsi, Francesca; Cirillo, Mario; Tedeschi, Gioacchino [MRI Research Center SUN-FISM-Neurological Institute for Diagnosis and Care ' ' Hermitage Capodimonte' ' , Naples (Italy); Second University of Naples, Department of Medical, Surgical, Neurological, Metabolic and Aging Sciences, Naples (Italy); Esposito, Fabrizio [University of Salerno, Department of Medicine and Surgery, Baronissi (Salerno) (Italy); Maastricht University, Department of Cognitive Neuroscience, Maastricht (Netherlands)

2016-02-15

Q-ball imaging (QBI) is one of the typical data models for quantifying white matter (WM) anisotropy in diffusion-weighted MRI (DwMRI) studies. Brain and spinal investigation by high angular resolution DwMRI (high angular resolution imaging (HARDI)) protocols exhibits higher angular resolution in diffusion imaging compared to low angular resolution models, although with longer acquisition times. We aimed to assess the difference between QBI-derived anisotropy values from high and low angular resolution DwMRI protocols and their potential advantages or shortcomings in neuroradiology. Brain DwMRI data sets were acquired in seven healthy volunteers using both HARDI (b = 3000 s/mm{sup 2}, 54 gradient directions) and low angular resolution (b = 1000 s/mm{sup 2}, 32 gradient directions) acquisition schemes. For both sequences, tract of interest tractography and generalized fractional anisotropy (GFA) measures were extracted by using QBI model and were compared between the two data sets. QBI tractography and voxel-wise analyses showed that some WM tracts, such as corpus callosum, inferior longitudinal, and uncinate fasciculi, were reconstructed as one-dominant-direction fiber bundles with both acquisition schemes. In these WM tracts, mean percent different difference in GFA between the two data sets was less than 5 %. Contrariwise, multidirectional fiber bundles, such as corticospinal tract and superior longitudinal fasciculus, were more accurately depicted by HARDI acquisition scheme. Our results suggest that the design of optimal DwMRI acquisition protocols for clinical investigation of WM anisotropy by QBI models should consider the specific brain target regions to be explored, inducing researchers to a trade-off choice between angular resolution and acquisition time. (orig.)

New developments of radio-astronomy in the sub-mmwave region

International Nuclear Information System (INIS)

Matthews, H.E.

1989-01-01

Astronomy at submillimeter wavelengths is a technically demanding discipline which is coming of age through the recent construction of several large ground-based facilities and continuing advances in receiver technology. The current status of the field is reviewed with attention being paid particularly to the potential contributions to astrophysics and to the major difficulties facing the observer at these wavelengths. The results of surveys for molecular transitions and examples of the uses of such lines in determining excitation and other parameters of circum- and interstellar material is discussed. Observations of continuum radiation, principally of cold dust, is also touched upon. Both line and continuum studies have great potential at these wavelengths in the study of protostellar objects, as well as in the late stages of stellar evolution. Prospects for the future development of sub-mm astronomy are bright; plans to overcome the limitations imposed by the atmosphere using satellite technology, and to increase angular resolution by the use of interferometry are reviewed

Angular difference feature extraction for urban scene classification using ZY-3 multi-angle high-resolution satellite imagery

Science.gov (United States)

Huang, Xin; Chen, Huijun; Gong, Jianya

2018-01-01

Spaceborne multi-angle images with a high-resolution are capable of simultaneously providing spatial details and three-dimensional (3D) information to support detailed and accurate classification of complex urban scenes. In recent years, satellite-derived digital surface models (DSMs) have been increasingly utilized to provide height information to complement spectral properties for urban classification. However, in such a way, the multi-angle information is not effectively exploited, which is mainly due to the errors and difficulties of the multi-view image matching and the inaccuracy of the generated DSM over complex and dense urban scenes. Therefore, it is still a challenging task to effectively exploit the available angular information from high-resolution multi-angle images. In this paper, we investigate the potential for classifying urban scenes based on local angular properties characterized from high-resolution ZY-3 multi-view images. Specifically, three categories of angular difference features (ADFs) are proposed to describe the angular information at three levels (i.e., pixel, feature, and label levels): (1) ADF-pixel: the angular information is directly extrapolated by pixel comparison between the multi-angle images; (2) ADF-feature: the angular differences are described in the feature domains by comparing the differences between the multi-angle spatial features (e.g., morphological attribute profiles (APs)). (3) ADF-label: label-level angular features are proposed based on a group of urban primitives (e.g., buildings and shadows), in order to describe the specific angular information related to the types of primitive classes. In addition, we utilize spatial-contextual information to refine the multi-level ADF features using superpixel segmentation, for the purpose of alleviating the effects of salt-and-pepper noise and representing the main angular characteristics within a local area. The experiments on ZY-3 multi-angle images confirm that the proposed

A primary scintillation gated high pressure position sensitive gas scintillation proportional counter (HPGSPC) for applications to x-ray astronomy

International Nuclear Information System (INIS)

Giarrusso, S.; Manzo, G.; Re, S.

1985-01-01

The authors describe a new instrument for x-ray astronomy. The instrument, based on a high pressure (5 atm.), xenon filled, position sensitive Gas Scintillation Proportional counter (HPGSPC) is expected to feature an energy resolution better than 4% at 60 keV, an angular resolution of approximately 20 arc-minutes over the full energy range (4 to 100 keV) and a field of view (FOV) of up to 30x30 degrees. A prototype flight unit of the gas cell on which the instrument is based is presently under technological development in the framework of the SAX project

Accurate Mass Measurements for Planetary Microlensing Events Using High Angular Resolution Observations

Directory of Open Access Journals (Sweden)

Jean-Philippe Beaulieu

2018-04-01

Full Text Available The microlensing technique is a unique method to hunt for cold planets over a range of mass and separation, orbiting all varieties of host stars in the disk of our galaxy. It provides precise mass-ratio and projected separations in units of the Einstein ring radius. In order to obtain the physical parameters (mass, distance, orbital separation of the system, it is necessary to combine the result of light curve modeling with lens mass-distance relations and/or perform a Bayesian analysis with a galactic model. A first mass-distance relation could be obtained from a constraint on the Einstein ring radius if the crossing time of the source over the caustic is measured. It could then be supplemented by secondary constraints such as parallax measurements, ideally by using coinciding ground and space-born observations. These are still subject to degeneracies, like the orbital motion of the lens. A third mass-distance relation can be obtained thanks to constraints on the lens luminosity using high angular resolution observations with 8 m class telescopes or the Hubble Space Telescope. The latter route, although quite inexpensive in telescope time is very effective. If we have to rely heavily on Bayesian analysis and limited constraints on mass-distance relations, the physical parameters are determined to 30–40% typically. In a handful of cases, ground-space parallax is a powerful route to get stronger constraint on masses. High angular resolution observations will be able to constrain the luminosity of the lenses in the majority of the cases, and in favorable circumstances it is possible to derive physical parameters to 10% or better. Moreover, these constraints will be obtained in most of the planets to be discovered by the Euclid and WFIRST satellites. We describe here the state-of-the-art approaches to measure lens masses and distances with an emphasis on high angular resolution observations. We will discuss the challenges, recent results and

The relationship between Class I and Class II methanol masers at high angular resolution

Science.gov (United States)

McCarthy, T. P.; Ellingsen, S. P.; Voronkov, M. A.; Cimò, G.

2018-06-01

We have used the Australia Telescope Compact Array (ATCA) to make the first high-resolution observations of a large sample of class I methanol masers in the 95-GHz (80-71A+) transition. The target sources consist of a statistically complete sample of 6.7-GHz class II methanol masers with an associated 95-GHz class I methanol maser, enabling a detailed study of the relationship between the two methanol maser classes at arcsecond angular resolution. These sources have been previously observed at high resolution in the 36- and 44-GHz transitions, allowing comparison between all three class I maser transitions. In total, 172 95-GHz maser components were detected across the 32 target sources. We find that at high resolution, when considering matched maser components, a 3:1 flux density ratio is observed between the 95- and 44-GHz components, consistent with a number of previous lower angular resolution studies. The 95-GHz maser components appear to be preferentially located closer to the driving sources and this may indicate that this transition is more strongly inverted nearby to background continuum sources. We do not observe an elevated association rate between 95-GHz maser emission and more evolved sources, as indicated by the presence of 12.2-GHz class II masers. We find that in the majority of cases where both class I and class II methanol emission is observed, some component of the class I emission is associated with a likely outflow candidate.

Improving the angular resolution of existing air shower arrays by adding a thin layer of lead

International Nuclear Information System (INIS)

Poirier, J.; Mikocki, S.

1987-01-01

Calculations show that placing a thin sheet of lead above conventional extensive air shower counters yields an additional signal which is earlier in time. This will improve the array's angular resolution. (orig.)

Method of separation of air showers initiated by γ-quanta and protons using Cherenkov light angular characteristics in combination and angular resolution estimate for an array of several optical telescopes

International Nuclear Information System (INIS)

Anokhina, A.M.; Galkin, V.I.; Ivanenko, I.P.; Roganova, T.M.

1990-01-01

Computer simulation of optical characteristics of air showers was carried out. On the basis of multidimensional analysis of Cherenkov light angular distribution possibility is considered to distinguish γ-showers from proton showers. Also an estimate for angular resolution is given for an array of five optical telescopes situated at Mt.Aragats. 7 refs.; 10 figs.; 11 tabs

The impact of clustering and angular resolution on far-infrared and millimeter continuum observations

Science.gov (United States)

Béthermin, Matthieu; Wu, Hao-Yi; Lagache, Guilaine; Davidzon, Iary; Ponthieu, Nicolas; Cousin, Morgane; Wang, Lingyu; Doré, Olivier; Daddi, Emanuele; Lapi, Andrea

2017-11-01

Follow-up observations at high-angular resolution of bright submillimeter galaxies selected from deep extragalactic surveys have shown that the single-dish sources are comprised of a blend of several galaxies. Consequently, number counts derived from low- and high-angular-resolution observations are in tension. This demonstrates the importance of resolution effects at these wavelengths and the need for realistic simulations to explore them. We built a new 2 deg2 simulation of the extragalactic sky from the far-infrared to the submillimeter. It is based on an updated version of the 2SFM (two star-formation modes) galaxy evolution model. Using global galaxy properties generated by this model, we used an abundance-matching technique to populate a dark-matter lightcone and thus simulate the clustering. We produced maps from this simulation and extracted the sources, and we show that the limited angular resolution of single-dish instruments has a strong impact on (sub)millimeter continuum observations. Taking into account these resolution effects, we are reproducing a large set of observables, as number counts and their evolution with redshift and cosmic infrared background power spectra. Our simulation consistently describes the number counts from single-dish telescopes and interferometers. In particular, at 350 and 500 μm, we find that the number counts measured by Herschel between 5 and 50 mJy are biased towards high values by a factor 2, and that the redshift distributions are biased towards low redshifts. We also show that the clustering has an important impact on the Herschel pixel histogram used to derive number counts from P(D) analysis. We find that the brightest galaxy in the beam of a 500 μm Herschel source contributes on average to only 60% of the Herschel flux density, but that this number will rise to 95% for future millimeter surveys on 30 m-class telescopes (e.g., NIKA2 at IRAM). Finally, we show that the large number density of red Herschel sources

Finsler geometry on higher order tensor fields and applications to high angular resolution diffusion imaging

NARCIS (Netherlands)

Astola, L.J.; Florack, L.M.J.

2010-01-01

We study 3D-multidirectional images, using Finsler geometry. The application considered here is in medical image analysis, specifically in High Angular Resolution Diffusion Imaging (HARDI) [24] of the brain. The goal is to reveal the architecture of the neural fibers in brain white matter. To the

Finsler geometry on higher order tensor fields and applications to high angular resolution diffusion imaging

NARCIS (Netherlands)

Astola, L.J.; Florack, L.M.J.

2011-01-01

We study 3D-multidirectional images, using Finsler geometry. The application considered here is in medical image analysis, specifically in High Angular Resolution Diffusion Imaging (HARDI) (Tuch et al. in Magn. Reson. Med. 48(6):1358–1372, 2004) of the brain. The goal is to reveal the architecture

Finsler geometry on higher order tensor fields and applications to high angular resolution diffusion imaging.

NARCIS (Netherlands)

Astola, L.; Florack, L.

2011-01-01

We study 3D-multidirectional images, using Finsler geometry. The application considered here is in medical image analysis, specifically in High Angular Resolution Diffusion Imaging (HARDI) (Tuch et al. in Magn. Reson. Med. 48(6):1358–1372, 2004) of the brain. The goal is to reveal the architecture

Evaluation of Medium Spatial Resolution BRDF-Adjustment Techniques Using Multi-Angular SPOT4 (Take5) Acquisitions

OpenAIRE

Claverie, Martin; Vermote, Eric; Franch, Belen; He, Tao; Hagolle, Olivier; Kadiri, Mohamed; Masek, Jeff

2015-01-01

High-resolution sensor Surface Reflectance (SR) data are affected by surface anisotropy but are difficult to adjust because of the low temporal frequency of the acquisitions and the low angular sampling. This paper evaluates five high spatial resolution Bidirectional Reflectance Distribution Function (BRDF) adjustment techniques. The evaluation is based on the noise level of the SR Time Series (TS) corrected to a normalized geometry (nadir view, 45° sun zenith angle) extracted from the multi-...

Innovation in Astronomy Education

Science.gov (United States)

Pasachoff, Jay M.; Ros, Rosa M.; Pasachoff, Naomi

2013-01-01

large astronomical data holdings; Poster abstracts; Part IV. Practical Issues Connected with the Implementation of the 2003 IAU Resolution: Introduction; 33. Stellar evolution for students of Moscow University; 34. Astronomy for everybody: An approach from the CASAO/NAUH view; 35. Toward a new program in astronomy education in secondary schools in Turkey; 36. Universe awareness for young children; 37. Education in Egypt and Egyptian responses to eclipses; 38. Astronomy in the cultural heritage of African societies; 39. Education at the Pierre Auger Observatory: the cinema as a tool in science education; 40. Freshman seminars: interdisciplinary engagements in astronomy; 41. Astronomy for teachers; Poster abstracts; Conclusion.

Angular-resolution and material-characterization measurements for a dual-particle imaging system with mixed-oxide fuel

Energy Technology Data Exchange (ETDEWEB)

Poitrasson-Rivière, Alexis, E-mail: alexispr@umich.edu [Department of Nuclear Engineering & Radiological Sciences, University of Michigan, Ann Arbor, MI 48109 (United States); Polack, J. Kyle; Hamel, Michael C.; Klemm, Dietrich D.; Ito, Kai; McSpaden, Alexander T.; Flaska, Marek; Clarke, Shaun D.; Pozzi, Sara A. [Department of Nuclear Engineering & Radiological Sciences, University of Michigan, Ann Arbor, MI 48109 (United States); Tomanin, Alice [Lainsa-Italia S.R.L., Via E. Fermi 2749, 21027 Ispra, VA (Italy); Peerani, Paolo [European Commission, Joint Research Centre, Institute for Transuranium Elements, 21027 Ispra, VA (Italy)

2015-10-11

A dual-particle imaging (DPI) system, capable of simultaneously imaging fast neutrons and gamma rays, has been operated in the presence of mixed-oxide (MOX) fuel to assess the system's angular resolution and material-characterization capabilities. The detection principle is based on the scattering physics of neutrons (elastic scattering) and gamma rays (Compton scattering) in organic and inorganic scintillators. The detection system is designed as a combination of a two-plane Compton camera and a neutron-scatter camera. The front plane consists of EJ-309 liquid scintillators and the back plane consists of interleaved EJ-309 and NaI(Tl) scintillators. MCNPX-PoliMi was used to optimize the geometry of the system and the resulting prototype was built and tested using a Cf-252 source as an SNM surrogate. A software package was developed to acquire and process data in real time. The software was used for a measurement campaign to assess the angular resolution of the imaging system with MOX samples. Measurements of two MOX canisters of similar isotopics and intensity were performed for 6 different canister separations (from 5° to 30°, corresponding to distances of 21 cm and 131 cm, respectively). The measurements yielded a minimum separation of 20° at 2.5 m (86-cm separation) required to see 2 separate hot spots. Additionally, the results displayed good agreement with MCNPX-PoliMi simulations. These results indicate an angular resolution between 15° and 20°, given the 5° step. Coupled with its large field of view, and its capability to differentiate between spontaneous fission and (α,n) sources, the DPI system shows its potential for nuclear-nonproliferation applications.

Investigation of angular and axial smoothing of PET data

International Nuclear Information System (INIS)

Daube-Witherspoon, M.E.; Carson, R.E.

1996-01-01

Radial filtering of emission and transmission data is routinely performed in PET during reconstruction in order to reduce image noise. Angular smoothing is not typically done, due to the introduction of a non-uniform resolution loss; axial filtering is also not usually performed on data acquired in 2D mode. The goal of this paper was to assess the effects of angular and axial smoothing on noise and resolution. Angular and axial smoothing was incorporated into the reconstruction process on the Scanditronix PC2048-15B brain PET scanner. In-plane spatial resolution and noise reduction were measured for different amounts of radial and angular smoothing. For radial positions away from the center of the scanner, noise reduction and degraded tangential resolution with no loss of radial resolution were seen. Near the center, no resolution loss was observed, but there was also no reduction in noise for angular filters up to a 7 degrees FWHM. These results can be understood by considering the combined effects of smoothing projections across rows (angles) and then summing (backprojecting). Thus, angular smoothing is not optimal due to its anisotropic noise reduction and resolution degradation properties. However, uniform noise reduction comparable to that seen with radial filtering can be achieved with axial smoothing of transmission data. The axial results suggest that combined radial and axial transmission smoothing could lead to improved noise characteristics with more isotropic resolution degradation

Measurement of the position resolution of the Gas Pixel Detector

International Nuclear Information System (INIS)

Soffitta, Paolo; Muleri, Fabio; Fabiani, Sergio; Costa, Enrico; Bellazzini, Ronaldo; Brez, Alessandro; Minuti, Massimo; Pinchera, Michele; Spandre, Gloria

2013-01-01

The Gas Pixel Detector was designed and built as a focal plane instrument for X-ray polarimetry of celestial sources, the last unexplored subtopics of X-ray astronomy. It promises to perform detailed and sensitive measurements resolving extended sources and detecting polarization in faint sources in crowded fields at the focus of telescopes of good angular resolution. Its polarimetric and spectral capability were already studied in earlier works. Here we investigate for the first time, with both laboratory measurements and Monte Carlo simulations, its imaging properties to confirm its unique capability to carry out imaging spectral-polarimetry in future X-ray missions.

A super-high angular resolution principle for coded-mask X-ray imaging beyond the diffraction limit of a single pinhole

International Nuclear Information System (INIS)

Zhang Chen; Zhang Shuangnan

2009-01-01

High angular resolution X-ray imaging is always useful in astrophysics and solar physics. In principle, it can be performed by using coded-mask imaging with a very long mask-detector distance. Previously, the diffraction-interference effect was thought to degrade coded-mask imaging performance dramatically at the low energy end with its very long mask-detector distance. The diffraction-interference effect is described with numerical calculations, and the diffraction-interference cross correlation reconstruction method (DICC) is developed in order to overcome the imaging performance degradation. Based on the DICC, a super-high angular resolution principle (SHARP) for coded-mask X-ray imaging is proposed. The feasibility of coded mask imaging beyond the diffraction limit of a single pinhole is demonstrated with simulations. With the specification that the mask element size is 50 x 50 μm 2 and the mask-detector distance is 50 m, the achieved angular resolution is 0.32 arcsec above about 10 keV and 0.36 arcsec at 1.24 keV (λ = 1 nm), where diffraction cannot be neglected. The on-axis source location accuracy is better than 0.02 arcsec. Potential applications for solar observations and wide-field X-ray monitors are also briefly discussed. (invited reviews)

Active x-ray optics for high resolution space telescopes

Science.gov (United States)

Doel, Peter; Atkins, Carolyn; Brooks, D.; Feldman, Charlotte; Willingale, Richard; Button, Tim; Rodriguez Sanmartin, Daniel; Meggs, Carl; James, Ady; Willis, Graham; Smith, Andy

2017-11-01

The Smart X-ray Optics (SXO) Basic Technology project started in April 2006 and will end in October 2010. The aim is to develop new technologies in the field of X-ray focusing, in particular the application of active and adaptive optics. While very major advances have been made in active/adaptive astronomical optics for visible light, little was previously achieved for X-ray optics where the technological challenges differ because of the much shorter wavelengths involved. The field of X-ray astronomy has been characterized by the development and launch of ever larger observatories with the culmination in the European Space Agency's XMM-Newton and NASA's Chandra missions which are currently operational. XMM-Newton uses a multi-nested structure to provide modest angular resolution ( 10 arcsec) but large effective area, while Chandra sacrifices effective area to achieve the optical stability necessary to provide sub-arc second resolution. Currently the European Space Agency (ESA) is engaged in studies of the next generation of X-ray space observatories, with the aim of producing telescopes with increased sensitivity and resolution. To achieve these aims several telescopes have been proposed, for example ESA and NASA's combined International X-ray Observatory (IXO), aimed at spectroscopy, and NASA's Generation-X. In the field of X-ray astronomy sub 0.2 arcsecond resolution with high efficiency would be very exciting. Such resolution is unlikely to be achieved by anything other than an active system. The benefits of a such a high resolution would be important for a range of astrophysics subjects, for example the potential angular resolution offered by active X-ray optics could provide unprecedented structural imaging detail of the Solar Wind bowshock interaction of comets, planets and similar objects and auroral phenomena throughout the Solar system using an observing platform in low Earth orbit. A major aim of the SXO project was to investigate the production of thin

Adaptive Optics, LLLFT Interferometry, Astronomy

National Research Council Canada - National Science Library

2002-01-01

We propose to build a three telescope Michelson optical interferometer equipped with wavefront compensation technology as a demonstration and test bed for high resolution Deep Space Surveillance (DSS) and Astronomy...

Discrete time interval measurement system: fundamentals, resolution and errors in the measurement of angular vibrations

International Nuclear Information System (INIS)

Gómez de León, F C; Meroño Pérez, P A

2010-01-01

The traditional method for measuring the velocity and the angular vibration in the shaft of rotating machines using incremental encoders is based on counting the pulses at given time intervals. This method is generically called the time interval measurement system (TIMS). A variant of this method that we have developed in this work consists of measuring the corresponding time of each pulse from the encoder and sampling the signal by means of an A/D converter as if it were an analog signal, that is to say, in discrete time. For this reason, we have denominated this method as the discrete time interval measurement system (DTIMS). This measurement system provides a substantial improvement in the precision and frequency resolution compared with the traditional method of counting pulses. In addition, this method permits modification of the width of some pulses in order to obtain a mark-phase on every lap. This paper explains the theoretical fundamentals of the DTIMS and its application for measuring the angular vibrations of rotating machines. It also displays the required relationship between the sampling rate of the signal, the number of pulses of the encoder and the rotating velocity in order to obtain the required resolution and to delimit the methodological errors in the measurement

Recent Progress in Adjustable X-ray Optics for Astronomy

Science.gov (United States)

Reid, Paul B.; Allured, Ryan; Cotroneo, Vincenzo; McMuldroch, Stuart; Marquez, Vanessa; Schwartz, Daniel A.; Vikhlinin, Alexey; ODell, Stephen L.; Ramsey, Brian; Trolier-McKinstry, Susan;

Improving angular resolution with Scan-MUSIC algorithm for real complex targets using 35-GHz millimeter-wave radar

Science.gov (United States)

Ly, Canh

2004-08-01

Scan-MUSIC algorithm, developed by the U.S. Army Research Laboratory (ARL), improves angular resolution for target detection with the use of a single rotatable radar scanning the angular region of interest. This algorithm has been adapted and extended from the MUSIC algorithm that has been used for a linear sensor array. Previously, it was shown that the SMUSIC algorithm and a Millimeter Wave radar can be used to resolve two closely spaced point targets that exhibited constructive interference, but not for the targets that exhibited destructive interference. Therefore, there were some limitations of the algorithm for the point targets. In this paper, the SMUSIC algorithm is applied to a problem of resolving real complex scatterer-type targets, which is more useful and of greater practical interest, particular for the future Army radar system. The paper presents results of the angular resolution of the targets, an M60 tank and an M113 Armored Personnel Carrier (APC), that are within the mainlobe of a Κα-band radar antenna. In particular, we applied the algorithm to resolve centroids of the targets that were placed within the beamwidth of the antenna. The collected coherent data using the stepped-frequency radar were compute magnitudely for the SMUSIC calculation. Even though there were significantly different signal returns for different orientations and offsets of the two targets, we resolved those two target centroids when they were as close as about 1/3 of the antenna beamwidth.

Astronomy and Creationism.

Science.gov (United States)

Morrison, David

1982-01-01

Discusses the effects on astronomy courses/curriculum if equal time were given to the concept that the universe was created in its present form about ten thousand years ago. Includes the full text on a resolution concerning creationism passed by the Board of Directors of the Astronomical Society of the Pacific. (Author/JN)

Journal of Astrophysics and Astronomy | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Journal of Astrophysics and Astronomy. N. Kameswara Rao. Articles written in Journal of Astrophysics and Astronomy. Volume 26 Issue 2-3 June-September 2005 pp 331-338. High Resolution Stellar Spectroscopy with VBT Echelle Spectrometer · N. Kameswara Rao S. Sriram K. Jayakumar F. Gabriel.

The MIRAX x-ray astronomy transient mission

Science.gov (United States)

Braga, João; Mejía, Jorge

2006-06-01

The Monitor e Imageador de Raios-X (MIRAX) is a small (~250 kg) X-ray astronomy satellite mission designed to monitor the central Galactic plane for transient phenomena. With a field-of-view of ~1000 square degrees and an angular resolution of ~6 arcmin, MIRAX will provide an unprecedented discovery-space coverage to study X-ray variability in detail, from fast X-ray novae to long-term (~several months) variable phenomena. Chiefly among MIRAX science objectives is its capability of providing simultaneous complete temporal coverage of the evolution of a large number of accreting black holes, including a detailed characterization of the spectral state transitions in these systems. MIRAX's instruments will include a soft X-ray (2-18 keV) and two hard X-ray (10-200 keV) coded-aperture imagers, with sensitivities of ~5 and ~2.6 mCrab/day, respectively. The hard X-ray imagers will be built at the Instituto Nacional de Pesquisas Espaciais (INPE), Brazil, in close collaboration with the Center for Astrophysics & Space Sciences (CASS) of the University of California, San Diego (UCSD) and the Institut fur Astronomie und Astrophysik of the University of Tubingen (IAAT) in Germany; UCSD will provide the crossed-strip position-sensitive (0.5- mm spatial resolution) CdZnTe (CZT) hard X-ray detectors. The soft X-ray camera, provided by the Space Research Organization Netherlands (SRON), will be the spare flight unit of the Wide Field Cameras that flew on the Italian-Dutch satellite BeppoSAX. MIRAX is an approved mission of the Brazilian Space Agency (Agnecia Espacial Brasileira - AEB) and is scheduled to be launched in 2011 in a low-altitude (~550 km) circular equatorial orbit. In this paper we present recent developments in the mission planning and design, as well as Monte Carlo simulations performed on the GEANT-based package MGGPOD environment (Weidenspointner et al. 2004) and new algorithms for image digital processing. Simulated images of the central Galactic plane as it

Lightweight and High-Resolution Single Crystal Silicon Optics for X-ray Astronomy

Science.gov (United States)

Zhang, William W.; Biskach, Michael P.; Chan, Kai-Wing; Mazzarella, James R.; McClelland, Ryan S.; Riveros, Raul E.; Saha, Timo T.; Solly, Peter M.

2016-01-01

We describe an approach to building mirror assemblies for next generation X-ray telescopes. It incorporates knowledge and lessons learned from building existing telescopes, including Chandra, XMM-Newton, Suzaku, and NuSTAR, as well as from our direct experience of the last 15 years developing mirror technology for the Constellation-X and International X-ray Observatory mission concepts. This approach combines single crystal silicon and precision polishing, thus has the potential of achieving the highest possible angular resolution with the least possible mass. Moreover, it is simple, consisting of several technical elements that can be developed independently in parallel. Lastly, it is highly amenable to mass production, therefore enabling the making of telescopes of very large photon collecting areas.

Direct observation of strain in bulk subgrains and dislocation walls by high angular resolution three-dimensional X-ray diffraction

DEFF Research Database (Denmark)

Jakobsen, Bo; Lienert, U.; Almer, J.

2008-01-01

The X-ray diffraction (XRD) method "high angular resolution 3DXRD" is briefly introduced, and results are presented for a single bulk grain in a polycrystalline copper sample deformed in tension. It is found that the three-dimensional reciprocal-space intensity distribution of a 400 reflection...

Use of the maximum entropy method in X-ray astronomy

International Nuclear Information System (INIS)

Willingale, R.

1981-01-01

An algorithm used to apply the maximum entropy method in X-ray astronomy is described. It is easy to programme on a digital computer and fast enough to allow processing of two-dimensional images. The method gives good noise suppression without loss of instrumental resolution and has been successfully applied to several data analysis problems in X-ray astronomy. The restoration of a high-resolution image from the Einstein Observatory demonstrates the use of the algorithm. (author)

HIGH ANGULAR RESOLUTION OBSERVATIONS OF FOUR CANDIDATE BLAST HIGH-MASS STARLESS CORES

International Nuclear Information System (INIS)

Olmi, Luca; Poventud, Carlos M.; Araya, Esteban D.; Chapin, Edward L.; Gibb, Andrew; Hofner, Peter; Martin, Peter G.

2010-01-01

We discuss high angular resolution observations of ammonia toward four candidate high-mass starless cores (HMSCs). The cores were identified by the Balloon-borne Large Aperture Submillimeter Telescope (BLAST) during its 2005 survey of the Vulpecula region where 60 compact sources were detected simultaneously at 250, 350, and 500 μm. Four of these cores, with no IRAS-PSC or MSX counterparts, were mapped with the NRAO Very Large Array and observed with the Effelsberg 100 m telescope in the NH 3 (1,1) and (2,2) spectral lines. Our observations indicate that the four cores are cold (T k -1 . The four BLAST cores appear to be colder and more quiescent than other previously observed HMSC candidates, suggesting an earlier stage of evolution.

In vivo high angular resolution diffusion-weighted imaging of mouse brain at 16.4 Tesla.

Directory of Open Access Journals (Sweden)

Othman I Alomair

Full Text Available Magnetic Resonance Imaging (MRI of the rodent brain at ultra-high magnetic fields (> 9.4 Tesla offers a higher signal-to-noise ratio that can be exploited to reduce image acquisition time or provide higher spatial resolution. However, significant challenges are presented due to a combination of longer T1 and shorter T2/T2* relaxation times and increased sensitivity to magnetic susceptibility resulting in severe local-field inhomogeneity artefacts from air pockets and bone/brain interfaces. The Stejskal-Tanner spin echo diffusion-weighted imaging (DWI sequence is often used in high-field rodent brain MRI due to its immunity to these artefacts. To accurately determine diffusion-tensor or fibre-orientation distribution, high angular resolution diffusion imaging (HARDI with strong diffusion weighting (b >3000 s/mm2 and at least 30 diffusion-encoding directions are required. However, this results in long image acquisition times unsuitable for live animal imaging. In this study, we describe the optimization of HARDI acquisition parameters at 16.4T using a Stejskal-Tanner sequence with echo-planar imaging (EPI readout. EPI segmentation and partial Fourier encoding acceleration were applied to reduce the echo time (TE, thereby minimizing signal decay and distortion artefacts while maintaining a reasonably short acquisition time. The final HARDI acquisition protocol was achieved with the following parameters: 4 shot EPI, b = 3000 s/mm2, 64 diffusion-encoding directions, 125×150 μm2 in-plane resolution, 0.6 mm slice thickness, and 2h acquisition time. This protocol was used to image a cohort of adult C57BL/6 male mice, whereby the quality of the acquired data was assessed and diffusion tensor imaging (DTI derived parameters were measured. High-quality images with high spatial and angular resolution, low distortion and low variability in DTI-derived parameters were obtained, indicating that EPI-DWI is feasible at 16.4T to study animal models of white

SMA OBSERVATIONS OF CLASS 0 PROTOSTARS: A HIGH ANGULAR RESOLUTION SURVEY OF PROTOSTELLAR BINARY SYSTEMS

Energy Technology Data Exchange (ETDEWEB)

Chen Xuepeng [Purple Mountain Observatory, Chinese Academy of Sciences, 2 West Beijing Road, Nanjing 210008 (China); Arce, Hector G.; Dunham, Michael M. [Department of Astronomy, Yale University, Box 208101, New Haven, CT 06520-8101 (United States); Zhang Qizhou; Bourke, Tyler L. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Launhardt, Ralf; Henning, Thomas [Max Planck Institute for Astronomy, Koenigstuhl 17, D-69117 Heidelberg (Germany); Jorgensen, Jes K. [Niels Bohr Institute and Centre for Star and Planet Formation, Copenhagen University, Juliane Maries Vej 30, DK-2100 Copenhagen O (Denmark); Lee, Chin-Fei [Academia Sinica Institute of Astronomy and Astrophysics, P.O. Box 23-141, Taipei 106, Taiwan (China); Foster, Jonathan B. [Institute for Astrophysical Research, Boston University, Boston, MA 02215 (United States); Pineda, Jaime E., E-mail: xpchen@pmo.ac.cn, E-mail: xuepeng.chen@yale.edu [ESO, Karl Schwarzschild Str. 2, D-85748 Garching bei Munchen (Germany)

2013-05-10

We present high angular resolution 1.3 mm and 850 {mu}m dust continuum data obtained with the Submillimeter Array toward 33 Class 0 protostars in nearby clouds (distance < 500 pc), which represents so far the largest survey toward protostellar binary/multiple systems. The median angular resolution in the survey is 2.''5, while the median linear resolution is approximately 600 AU. Compact dust continuum emission is observed from all sources in the sample. Twenty-one sources in the sample show signatures of binarity/multiplicity, with separations ranging from 50 AU to 5000 AU. The numbers of singles, binaries, triples, and quadruples in the sample are 12, 14, 5, and 2, respectively. The derived multiplicity frequency (MF) and companion star fraction (CSF) for Class 0 protostars are 0.64 {+-} 0.08 and 0.91 {+-} 0.05, respectively, with no correction for completeness. The derived MF and CSF in this survey are approximately two times higher than the values found in the binary surveys toward Class I young stellar objects, and approximately three (for MF) and four (for CSF) times larger than the values found among main-sequence stars, with a similar range of separations. Furthermore, the observed fraction of high-order multiple systems to binary systems in Class 0 protostars (0.50 {+-} 0.09) is also larger than the fractions found in Class I young stellar objects (0.31 {+-} 0.07) and main-sequence stars ({<=}0.2). These results suggest that binary properties evolve as protostars evolve, as predicted by numerical simulations. The distribution of separations for Class 0 protostellar binary/multiple systems shows a general trend in which CSF increases with decreasing companion separation. We find that 67% {+-} 8% of the protobinary systems have circumstellar mass ratios below 0.5, implying that unequal-mass systems are preferred in the process of binary star formation. We suggest an empirical sequential fragmentation picture for binary star formation, based on this

Design and modeling of an additive manufactured thin shell for x-ray astronomy

Science.gov (United States)

Feldman, Charlotte; Atkins, Carolyn; Brooks, David; Watson, Stephen; Cochrane, William; Roulet, Melanie; Willingale, Richard; Doel, Peter

2017-09-01

Future X-ray astronomy missions require light-weight thin shells to provide large collecting areas within the weight limits of launch vehicles, whilst still delivering angular resolutions close to that of Chandra (0.5 arc seconds). Additive manufacturing (AM), also known as 3D printing, is a well-established technology with the ability to construct or `print' intricate support structures, which can be both integral and light-weight, and is therefore a candidate technique for producing shells for space-based X-ray telescopes. The work described here is a feasibility study into this technology for precision X-ray optics for astronomy and has been sponsored by the UK Space Agency's National Space Technology Programme. The goal of the project is to use a series of test samples to trial different materials and processes with the aim of developing a viable path for the production of an X-ray reflecting prototype for astronomical applications. The initial design of an AM prototype X-ray shell is presented with ray-trace modelling and analysis of the X-ray performance. The polishing process may cause print-through from the light-weight support structure on to the reflecting surface. Investigations in to the effect of the print-through on the X-ray performance of the shell are also presented.

TeachAstronomy.com - Digitizing Astronomy Resources

Science.gov (United States)

Hardegree-Ullman, Kevin; Impey, C. D.; Austin, C.; Patikkal, A.; Paul, M.; Ganesan, N.

2013-06-01

Teach Astronomy—a new, free online resource—can be used as a teaching tool in non-science major introductory college level astronomy courses, and as a reference guide for casual learners and hobbyists. Digital content available on Teach Astronomy includes: a comprehensive introductory astronomy textbook by Chris Impey, Wikipedia astronomy articles, images from Astronomy Picture of the Day archives and (new) AstroPix database, two to three minute topical video clips by Chris Impey, podcasts from 365 Days of Astronomy archives, and an RSS feed of astronomy news from Science Daily. Teach Astronomy features an original technology called the Wikimap to cluster, display, and navigate site search results. Development of Teach Astronomy was motivated by steep increases in textbook prices, the rapid adoption of digital resources by students and the public, and the modern capabilities of digital technology. This past spring semester Teach Astronomy was used as content supplement to lectures in a massive, open, online course (MOOC) taught by Chris Impey. Usage of Teach Astronomy has been steadily growing since its initial release in August of 2012. The site has users in all corners of the country and is being used as a primary teaching tool in at least four states.

Angularly-resolved elastic scatter from single particles collected over a large solid angle and with high resolution

International Nuclear Information System (INIS)

Aptowicz, Kevin B; Chang, Richard K

2005-01-01

Elastic light scattering from a single non-spherical particle of various morphologies has been measured simultaneously with a large angular range (90 deg. < θ < 165 deg. and 0 deg. < φ < 360 deg.) and with high angular resolution (1024 pixels in θ and 512 pixels in φ). Because the single-shot laser pulse is short (pulse duration of 70 ns), the tumbling and flowing particle can be treated as frozen in space. The large angle two-dimensional angular optical scattering (hereafter referred to as LA TAOS) intensity pattern, I(θ,φ), has been measured for a variety of particle morphology, such as the following: (1) single polystyrene latex (PSL) sphere; (2) cluster of PSL spheres; (3) single Bacillus subtilis (BG) spore; (4) cluster of BG spores; (5) dried aggregates of bio-aerosols as well as background clutter aerosols. All these measurements were made using the second harmonic of a Nd:YAG laser (0.532 μm). Islands structures in the LA TAOS patterns seem to be the prominent feature. Efforts are being made to extract metrics from these islands and compare them to theoretical results based on the T-matrix method

High resolution gamma-ray spectroscopy and the fascinating angular momentum realm of the atomic nucleus

International Nuclear Information System (INIS)

Riley, M A; Simpson, J; Paul, E S

2016-01-01

In 1974 Aage Bohr and Ben Mottelson predicted the different ‘phases’ that may be expected in deformed nuclei as a function of increasing angular momentum and excitation energy all the way up to the fission limit. While admitting their picture was highly conjectural they confidently stated ‘...with the ingenious experimental approaches that are being developed, we may look forward with excitement to the detailed spectroscopic studies that will illuminate the behaviour of the spinning quantised nucleus’ . High resolution gamma-ray spectroscopy has indeed been a major tool in studying the structure of atomic nuclei and has witnessed numerous significant advances over the last four decades. This article will select highlights from investigations at the Niels Bohr Institute, Denmark, and Daresbury Laboratory, UK, in the late 1970s and early 1980s, some of which have continued at other national laboratories in Europe and the USA to the present day. These studies illustrate the remarkable diversity of phenomena and symmetries exhibited by nuclei in the angular momentum–excitation energy plane that continue to surprise and fascinate scientists. (invited comment)

High resolution gamma-ray spectroscopy and the fascinating angular momentum realm of the atomic nucleus

Science.gov (United States)

Riley, M. A.; Simpson, J.; Paul, E. S.

2016-12-01

In 1974 Aage Bohr and Ben Mottelson predicted the different ‘phases’ that may be expected in deformed nuclei as a function of increasing angular momentum and excitation energy all the way up to the fission limit. While admitting their picture was highly conjectural they confidently stated ‘...with the ingenious experimental approaches that are being developed, we may look forward with excitement to the detailed spectroscopic studies that will illuminate the behaviour of the spinning quantised nucleus’. High resolution gamma-ray spectroscopy has indeed been a major tool in studying the structure of atomic nuclei and has witnessed numerous significant advances over the last four decades. This article will select highlights from investigations at the Niels Bohr Institute, Denmark, and Daresbury Laboratory, UK, in the late 1970s and early 1980s, some of which have continued at other national laboratories in Europe and the USA to the present day. These studies illustrate the remarkable diversity of phenomena and symmetries exhibited by nuclei in the angular momentum-excitation energy plane that continue to surprise and fascinate scientists.

Lucky Imaging in Astronomy

Science.gov (United States)

Brandner, Wolfgang; Hormuth, Felix

Lucky Imaging improves the angular resolution of astronomical observations hampered by atmospheric turbulence ("seeing"). Unlike adaptive optics, Lucky Imaging is a passive observing technique with individual integration times comparable to the atmospheric coherence time. Thanks to the advent of essentially noise free "Electron multiplying CCD" detectors, Lucky Imaging saw a renewed interest in the past decade. It is now routinely used at a number of 2-5-m class telescopes, such as ESO's NTT. We review the history of Lucky Imaging, present the technical implementation, describe the data analysis philosophy, and show some recent results obtained with this technique. We also discuss the advantages and limitations of Lucky Imaging compared to other passive and active high angular resolution observing techniques.

A hybrid concept (segmented plus monolithic fused silica shells) for a high-throughput and high-angular resolution x-ray mission (Lynx/X-Ray Surveyor like)

Science.gov (United States)

Basso, Stefano; Civitani, Marta; Pareschi, Giovanni; Parodi, Giancarlo

2017-09-01

Lynx is a large area and high angular resolution X-ray mission being studied by NASA to be presented to the next Decadal Survey for the implementation in the next decade. It aims to realize an X-ray telescope with the effective area similar to Athena (2 m2 at 1 keV) but with the same angular resolution of Chandra and a much larger Field Of View (up 20 arcmin x 20 arcmin). The science of X-ray Surveyor requires a large-throughput mirror assembly with sub-arcsec angular resolution. These future X-ray mirrors have a set of requirements which, collectively, represents very substantial advances over any currently in operation or planned for missions other than X-ray Surveyor. Of particular importance is achieving low mass per unit collecting area, while maintaining Chandra like angular resolution. Among the possible solutions under study, the direct polishing of both thin monolithic pseudo-cylindrical shells and segments made of fused silica are being considered as viable solutions for the implementation of the mirrors. Fused silica has very good thermomechanical parameters (including a very low CTE), making the material particularly well suited for for the production of the Lynx mirrors. It should be noted that the use of close shells is also very attractive, since the operations for the integration of the shells will be greatly simplified and the area lost due to the vignetting from the interfacing structures minimized even if the management of such big (diameter of 3 m) and thin shells have to be demonstrated. In this paper we will discuss a possible basic layout for a full shell mirror and a hybrid concept (segmented plus monolithic shells made of fused silica) as a second solution, for the Lynx/XRS telescope, discussing preliminary results in terms of optical and mechanical performance.

High mass star formation to the extremes: NGC 3603 at high angular resolution in the near-infrared

International Nuclear Information System (INIS)

Nuernberger, Dieter E A

2008-01-01

High angular resolution observations play a decisive role for our understanding of high mass star formation processes, both within our Galaxy and in extragalactic starburst regions. We take the Galactic starburst template NGC 3603 as paradigm and report here on high angular resolution JHK s L' observations of the enigmatic, highly reddened sources IRS 9A-C in the NGC 3603 region, which were performed with NACO at ESO's Very Large Telescope Yepun. These broad-band imaging data strongly support the classification of IRS 9A-C as high mass protostellar candidates. We also confirm unambiguously the membership of IRS 9A-C with the NGC 3603 region as gas and dust is seen to be stripped off from their circumstellar envelopes by strong stellar winds, originating from the high mass main sequence stars of the nearby OB cluster. The orientation of these gas and dust streamers coincides with that of a very faint, only marginally detected mini-pillar protruding from the adjacent molecular clump NGC 3603 MM 2. The L' data show extended envelopes around IRS 9A-C and reveal sub-structures therein which are indicative for non-spherically distributed material. It seems obvious that protostellar mass outflows are at work to clear cavities along the polar axes of the central protostar, and / or that circumstellar disks are taking shape.

Astronomy in the City for Astronomy Education

Science.gov (United States)

Ros, Rosa M.; Garc, Beatriz

2016-10-01

Astronomy is part of our culture. Astronomy cannot be isolated in a classroom, it has to be integrated in the normal life of teachers and students. ``Astronomy in the city'' is an important part of NASE (Network for Astronomy School Education) (Ros & Hemenway 2012). In each NASE course we introduce a ``working group session'' chaired by a local expert in cultural astronomy. The chair introduces several examples of astronomy in their city and after that, the participants have the opportunity to discuss and mention several similar examples. After this session all participants visit one or two sites proposed and introduced by the chair. After more than 5 years using this method we visited and discovered several examples of astronomy in the city: •Astronomy in ancient typical clothes. •Archaeological temples oriented according to the sunrise or set. •Petroglyphs with astronomical meaning. •Astronomy in monuments. •Sundials. •Oriented Colonial churches. •Astronomy in Souvenirs. In any case, teachers and students discover that Astronomy is part of their everyday life. They can take into account the Sun's path when they park their car or when they take a bus ``what is the best part in order to be seat in the shadow during the journey?'' The result is motivation to go with ``open eyes'' when they are in the street and they try to get more and more information about their surroundings. In summary, one of the main activities is to introduce local cultural aspects in NASE astronomy courses. The participants can discover a new approach to local culture from an astronomical point of view.

Simple Fourier optics formalism for high-angular-resolution systems and nulling interferometry.

Science.gov (United States)

Hénault, François

2010-03-01

Reviewed are various designs of advanced, multiaperture optical systems dedicated to high-angular-resolution imaging or to the detection of exoplanets by nulling interferometry. A simple Fourier optics formalism applicable to both imaging arrays and nulling interferometers is presented, allowing their basic theoretical relationships to be derived as convolution or cross-correlation products suitable for fast and accurate computation. Several unusual designs, such as a "superresolving telescope" utilizing a mosaicking observation procedure or a free-flying, axially recombined interferometer are examined, and their performance in terms of imaging and nulling capacity are assessed. In all considered cases, it is found that the limiting parameter is the diameter of the individual telescopes. A final section devoted to nulling interferometry shows an apparent superiority of axial versus multiaxial recombining schemes. The entire study is valid only in the framework of first-order geometrical optics and scalar diffraction theory. Furthermore, it is assumed that all entrance subapertures are optically conjugated with their associated exit pupils.

Future prospects for γ-ray astronomy

International Nuclear Information System (INIS)

Fichtel, C.

1981-01-01

As γ-ray astronomy moves from the discovery to the exploratory phase, the promise of γ-ray astrophysics noted by theorists in the late 1940s and 1950s is beginning to be realized. In the future, satellites should carry instruments that will have over an order of magnitude greater sensitivity than those flown thus far, and, for at least some portions of the γ-ray energy range, these detectors will also have substantially improved energy and angular resolution. The information to be obtained from these experiments should greatly enhance our knowledge of several astrophysical phenomena including the very energetic and nuclear processes associated with compact objects, astrophysical nucleosynthesis, solar particle acceleration, the chemical composition of the planets and other bodies of the Solar System, the structure of our Galaxy, the origin and dynamic pressure effects of the cosmic rays, high energy particles and energetic processes in other galaxies especially active ones, and the degree of matter-antimatter symmetry of the Universe. The γ-ray results of the forthcoming programs such as Gamma-I, the Gamma Ray Observatory, the γ-ray burst network, Solar Polar, and very high energy γ-ray telescopes on the ground will almost certainly provide justification for more sophisticated telescopes. These advanced instruments might be placed on the Space Platform currently under study by N.A.S.A. (author)

Future prospects for. gamma. -ray astronomy

Energy Technology Data Exchange (ETDEWEB)

Fichtel, C [National Aeronautics and Space Administration, Greenbelt, MD (USA). Goddard Space Flight Center

1981-06-30

As ..gamma..-ray astronomy moves from the discovery to the exploratory phase, the promise of ..gamma..-ray astrophysics noted by theorists in the late 1940s and 1950s is beginning to be realized. In the future, satellites should carry instruments that will have over an order of magnitude greater sensitivity than those flown thus far, and, for at least some portions of the ..gamma..-ray energy range, these detectors will also have substantially improved energy and angular resolution. The information to be obtained from these experiments should greatly enhance our knowledge of several astrophysical phenomena including the very energetic and nuclear processes associated with compact objects, astrophysical nucleosynthesis, solar particle acceleration, the chemical composition of the planets and other bodies of the Solar System, the structure of our Galaxy, the origin and dynamic pressure effects of the cosmic rays, high energy particles and energetic processes in other galaxies especially active ones, and the degree of matter-antimatter symmetry of the Universe. The ..gamma..-ray results of the forthcoming programs such as Gamma-I, the Gamma Ray Observatory, the ..gamma..-ray burst network, Solar Polar, and very high energy ..gamma..-ray telescopes on the ground will almost certainly provide justification for more sophisticated telescopes. These advanced instruments might be placed on the Space Platform currently under study by N.A.S.A.

Adjustable Grazing-Incidence X-Ray Optics

Science.gov (United States)

O'Dell, Stephen L.; Reid, Paul B.

2015-01-01

With its unique subarcsecond imaging performance, NASA's Chandra X-ray Observatory illustrates the importance of fine angular resolution for x-ray astronomy. Indeed, the future of x-ray astronomy relies upon x-ray telescopes with comparable angular resolution but larger aperture areas. Combined with the special requirements of nested grazing-incidence optics, mass, and envelope constraints of space-borne telescopes render such advances technologically and programmatically challenging. The goal of this technology research is to enable the cost-effective fabrication of large-area, lightweight grazing-incidence x-ray optics with subarcsecond resolution. Toward this end, the project is developing active x-ray optics using slumped-glass mirrors with thin-film piezoelectric arrays for correction of intrinsic or mount-induced distortions.

Noise reduction methods in the analysis of near infrared lunar occultation light curves for high angular resolution measurements

International Nuclear Information System (INIS)

Baug Tapas; Chandrasekhar Thyagarajan

2013-01-01

A lunar occultation (LO) technique in the near-infrared (NIR) provides angular resolution down to milliarcseconds for an occulted source, even with ground-based 1 m class telescopes. LO observations are limited to brighter objects because they require a high signal-to-noise ratio (S/N ∼40) for proper extraction of angular diameter values. Hence, methods to improve the S/N ratio by reducing noise using Fourier and wavelet transforms have been explored in this study. A sample of 54 NIR LO light curves observed with the IR camera at Mt Abu Observatory has been used. It is seen that both Fourier and wavelet methods have shown an improvement in S/N compared to the original data. However, the application of wavelet transforms causes a slight smoothing of the fringes and results in a higher value for angular diameter. Fourier transforms which reduce discrete noise frequencies do not distort the fringe. The Fourier transform method seems to be effective in improving the S/N, as well as improving the model fit, particularly in the fainter regime of our sample. These methods also provide a better model fit for brighter sources in some cases, though there may not be a significant improvement in S/N

Next Generation Astronomical X-ray Optics: High Angular Resolution, Light Weight, and Low Production Cost

Science.gov (United States)

Zhang. W. W.; Biskach, M. P.; Blake, P. N.; Chan, K. W.; Gaskin, J. A.; Hong, M. L.; Jones, W. D.; Kolos, L. D.; Mazzarella, J. R.; McClelland, R. S.;

Radiofrequency encoded angular-resolved light scattering

DEFF Research Database (Denmark)

Buckley, Brandon W.; Akbari, Najva; Diebold, Eric D.

2015-01-01

The sensitive, specific, and label-free classification of microscopic cells and organisms is one of the outstanding problems in biology. Today, instruments such as the flow cytometer use a combination of light scatter measurements at two distinct angles to infer the size and internal complexity...... of cells at rates of more than 10,000 per second. However, by examining the entire angular light scattering spectrum it is possible to classify cells with higher resolution and specificity. Current approaches to performing these angular spectrum measurements all have significant throughput limitations...... Encoded Angular-resolved Light Scattering (REALS), this technique multiplexes angular light scattering in the radiofrequency domain, such that a single photodetector captures the entire scattering spectrum from a particle over approximately 100 discrete incident angles on a single shot basis. As a proof...

Geometrically necessary dislocation densities in olivine obtained using high-angular resolution electron backscatter diffraction

Energy Technology Data Exchange (ETDEWEB)

Wallis, David, E-mail: davidwa@earth.ox.ac.uk [Department of Earth Sciences, University of Oxford, South Parks Road, Oxford, Oxfordshire, OX1 3AN (United Kingdom); Hansen, Lars N. [Department of Earth Sciences, University of Oxford, South Parks Road, Oxford, Oxfordshire, OX1 3AN (United Kingdom); Ben Britton, T. [Department of Materials, Imperial College London, Royal School of Mines, Exhibition Road, London SW7 2AZ (United Kingdom); Wilkinson, Angus J. [Department of Materials, University of Oxford, Parks Road, Oxford, Oxfordshire, OX1 3PH (United Kingdom)

2016-09-15

Dislocations in geological minerals are fundamental to the creep processes that control large-scale geodynamic phenomena. However, techniques to quantify their densities, distributions, and types over critical subgrain to polycrystal length scales are limited. The recent advent of high-angular resolution electron backscatter diffraction (HR-EBSD), based on diffraction pattern cross-correlation, offers a powerful new approach that has been utilised to analyse dislocation densities in the materials sciences. In particular, HR-EBSD yields significantly better angular resolution (<0.01°) than conventional EBSD (~0.5°), allowing very low dislocation densities to be analysed. We develop the application of HR-EBSD to olivine, the dominant mineral in Earth's upper mantle by testing (1) different inversion methods for estimating geometrically necessary dislocation (GND) densities, (2) the sensitivity of the method under a range of data acquisition settings, and (3) the ability of the technique to resolve a variety of olivine dislocation structures. The relatively low crystal symmetry (orthorhombic) and few slip systems in olivine result in well constrained GND density estimates. The GND density noise floor is inversely proportional to map step size, such that datasets can be optimised for analysing either short wavelength, high density structures (e.g. subgrain boundaries) or long wavelength, low amplitude orientation gradients. Comparison to conventional images of decorated dislocations demonstrates that HR-EBSD can characterise the dislocation distribution and reveal additional structure not captured by the decoration technique. HR-EBSD therefore provides a highly effective method for analysing dislocations in olivine and determining their role in accommodating macroscopic deformation. - Highlights: • Lattice orientation gradients in olivine were measured using HR-EBSD. • The limited number of olivine slip systems enable simple least squares inversion for GND

Terahertz heterodyne technology for astronomy and planetary science

NARCIS (Netherlands)

Wild, Wolfgang

2007-01-01

Heterodyne detection techniques play an important role in high-resolution spectroscopy in astronomy and planetary science. In particular, heterodyne technology in the Terahertz range has rapidly evolved in recent years. Cryogenically cooled receivers approaching quantum-limited sensitivity have been

Imaging X-ray astronomy

International Nuclear Information System (INIS)

Elvis, M.

1990-01-01

The launch of the High Energy Astrophysical Observatory, more appealingly called the Einstein Observatory, marked one of the most revolutionary steps taken in astrophysics this century. Its greater sensitivity compared with earlier satellites and its ability to make high spacial and spectral resolution observations transformed X-ray astronomy. This book is based on a Symposium held in Cambridge, Massachusetts, to celebrate a decade of Einstein Observatory's achievements. It discusses the contributions that this satellite has made to each area of modern astrophysics and the diversity of the ongoing work based on Einstein data. There is a guide to each of the main data bases now coming on-line to increase the availability and to preserve this valuable archive for the future. A review of NASA's next big X-ray mission, AXAF, and a visionary program for novel X-ray astronomy satellites by Riccardo Giacconi conclude this wide-ranging volume. (author)

Ghost Imaging Using Orbital Angular Momentum

Institute of Scientific and Technical Information of China (English)

赵生妹; 丁建; 董小亮; 郑宝玉

2011-01-01

We present a novel encoding scheme in a ghost-imaging system using orbital angular momentum. In the signal arm, object spatial information is encoded as a phase matrix. For an N-grey-scale object, different phase matrices, varying from 0 to K with increment n/N, are used for different greyscales, and then they are modulated to a signal beam by a spatial light modulator. According to the conservation of the orbital angular momentum in the ghost imaging system, these changes will give different coincidence rates in measurement, and hence the object information can be extracted in the idler arm. By simulations and experiments, the results show that our scheme can improve the resolution of the image effectively. Compared with another encoding method using orbital angular momentum, our scheme has a better performance for both characters and the image object.%We present a novel encoding scheme in a ghost-imaging system using orbital angular momentum.In the signal arm,object spatial information is encoded as a phase matrix.For an N-grey-scale object,different phase matrices,varying from 0 to π with increment π/N,are used for different greyscales,and then they are modulated to a signal beam by a spatial light modulator.According to the conservation of the orbital angular momentum in the ghost imaging system,these changes will give different coincidence rates in measurement,and hence the object information can be extracted in the idler arm.By simulations and experiments,the results show that our scheme can improve the resolution of the image effectively.Compared with another encoding method using orbital angular momentum,our scheme has a better performance for both characters and the image object.

Linear transforms for Fourier data on the sphere: application to high angular resolution diffusion MRI of the brain.

Science.gov (United States)

Haldar, Justin P; Leahy, Richard M

2013-05-01

This paper presents a novel family of linear transforms that can be applied to data collected from the surface of a 2-sphere in three-dimensional Fourier space. This family of transforms generalizes the previously-proposed Funk-Radon Transform (FRT), which was originally developed for estimating the orientations of white matter fibers in the central nervous system from diffusion magnetic resonance imaging data. The new family of transforms is characterized theoretically, and efficient numerical implementations of the transforms are presented for the case when the measured data is represented in a basis of spherical harmonics. After these general discussions, attention is focused on a particular new transform from this family that we name the Funk-Radon and Cosine Transform (FRACT). Based on theoretical arguments, it is expected that FRACT-based analysis should yield significantly better orientation information (e.g., improved accuracy and higher angular resolution) than FRT-based analysis, while maintaining the strong characterizability and computational efficiency of the FRT. Simulations are used to confirm these theoretical characteristics, and the practical significance of the proposed approach is illustrated with real diffusion weighted MRI brain data. These experiments demonstrate that, in addition to having strong theoretical characteristics, the proposed approach can outperform existing state-of-the-art orientation estimation methods with respect to measures such as angular resolution and robustness to noise and modeling errors. Copyright © 2013 Elsevier Inc. All rights reserved.

Power calculation of linear and angular incremental encoders

Science.gov (United States)

Prokofev, Aleksandr V.; Timofeev, Aleksandr N.; Mednikov, Sergey V.; Sycheva, Elena A.

2016-04-01

Automation technology is constantly expanding its role in improving the efficiency of manufacturing and testing processes in all branches of industry. More than ever before, the mechanical movements of linear slides, rotary tables, robot arms, actuators, etc. are numerically controlled. Linear and angular incremental photoelectric encoders measure mechanical motion and transmit the measured values back to the control unit. The capabilities of these systems are undergoing continual development in terms of their resolution, accuracy and reliability, their measuring ranges, and maximum speeds. This article discusses the method of power calculation of linear and angular incremental photoelectric encoders, to find the optimum parameters for its components, such as light emitters, photo-detectors, linear and angular scales, optical components etc. It analyzes methods and devices that permit high resolutions in the order of 0.001 mm or 0.001°, as well as large measuring lengths of over 100 mm. In linear and angular incremental photoelectric encoders optical beam is usually formulated by a condenser lens passes through the measuring unit changes its value depending on the movement of a scanning head or measuring raster. Past light beam is converting into an electrical signal by the photo-detecter's block for processing in the electrical block. Therefore, for calculating the energy source is a value of the desired value of the optical signal at the input of the photo-detecter's block, which reliably recorded and processed in the electronic unit of linear and angular incremental optoelectronic encoders. Automation technology is constantly expanding its role in improving the efficiency of manufacturing and testing processes in all branches of industry. More than ever before, the mechanical movements of linear slides, rotary tables, robot arms, actuators, etc. are numerically controlled. Linear and angular incremental photoelectric encoders measure mechanical motion and

Q0000-398 is a high-redshift quasar with a large angular size

International Nuclear Information System (INIS)

Gearhart, M.R.; Pacht, E.

1977-01-01

A study is described, using the three-element interferrometer at the National Radio Astronomy Observatory, West Virginia, to investigate whether any quasars exist that might be radio sources. It was found that Q0000-398 appeared to be a quasar of high red shift and large angular size. The interferrometer was operated with a 300-1200-1500 m baseline configuration at 2695 MHz. The radio map for Q0000-398 is shown, and has two weak components separated by 134 +- 40 arc s. If these components are associated with the optical object this quasar has the largest known angular size for its red shift value. The results reported for Q0000-398 and other quasars having considerable angular extent demonstrate the importance of considering radio selection effects in the angular diameter-red shift relationship, and since any radio selection effects are removed when quasars are selected optically, more extensive mapping programs should be undertaken, looking particularly for large scale structure around optically selected high-z quasars. (U.K.)

Resolution of potential ambiguities through farside angular structure: Semiclassical analysis

International Nuclear Information System (INIS)

Fricke, S.H.; Brandan, M.E.; McVoy, K.W.

1988-01-01

The optical potential fits summarized in the preceding paper are subjected to a semiclassical analysis of the Ford-Wheeler--Knoll-Schaeffer type. The important broad dips in their farside cross sections, which are essential in greatly reducing potential ambiguities, are found (in partial agreement with a suggestion of Goldberg's) to be mainly weak ''Airy'' or rainbow minima, that serve to identify deeply penetrating trajectories. The semiclassical analysis also permits the identification and understanding of a new category of discrete and continuous potential ambiguities, and suggests the manner in which specific features of the angular distributions (such as spacings and depths of various angular minima) determine the Woods-Saxon parameters found by a chi-squared search

Evaluation of Medium Spatial Resolution BRDF-Adjustment Techniques Using Multi-Angular SPOT4 (Take5 Acquisitions

Directory of Open Access Journals (Sweden)

Martin Claverie

2015-09-01

Full Text Available High-resolution sensor Surface Reflectance (SR data are affected by surface anisotropy but are difficult to adjust because of the low temporal frequency of the acquisitions and the low angular sampling. This paper evaluates five high spatial resolution Bidirectional Reflectance Distribution Function (BRDF adjustment techniques. The evaluation is based on the noise level of the SR Time Series (TS corrected to a normalized geometry (nadir view, 45° sun zenith angle extracted from the multi-angular acquisitions of SPOT4 over three study areas (one in Arizona, two in France during the five-month SPOT4 (Take5 experiment. Two uniform techniques (Cst, for Constant, and Av, for Average, relying on the Vermote–Justice–Bréon (VJB BRDF method, assume no variation in space of the BRDF shape. Two methods (VI-dis, for NDVI-based disaggregation and LC-dis, for Land-Cover based disaggregation are based on disaggregation of the MODIS-derived BRDF VJB parameters using vegetation index and land cover, respectively. The last technique (LUM, for Look-Up Map relies on the MCD43 MODIS BRDF products and a crop type data layer. The VI-dis technique produced the lowest level of noise corresponding to the most effective adjustment: reduction from directional to normalized SR TS noises by 40% and 50% on average, for red and near-infrared bands, respectively. The uniform techniques displayed very good results, suggesting that a simple and uniform BRDF-shape assumption is good enough to adjust the BRDF in such geometric configuration (the view zenith angle varies from nadir to 25°. The most complex techniques relying on land cover (LC-dis and LUM displayed contrasting results depending on the land cover.

High Angular Resolution Measurements of the Anisotropy of Reflectance of Sea Ice and Snow

Science.gov (United States)

Goyens, C.; Marty, S.; Leymarie, E.; Antoine, D.; Babin, M.; Bélanger, S.

2018-01-01

We introduce a new method to determine the anisotropy of reflectance of sea ice and snow at spatial scales from 1 m2 to 80 m2 using a multispectral circular fish-eye radiance camera (CE600). The CE600 allows measuring radiance simultaneously in all directions of a hemisphere at a 1° angular resolution. The spectral characteristics of the reflectance and its dependency on illumination conditions obtained from the camera are compared to those obtained with a hyperspectral field spectroradiometer manufactured by Analytical Spectral Device, Inc. (ASD). Results confirm the potential of the CE600, with the suggested measurement setup and data processing, to measure commensurable sea ice and snow hemispherical-directional reflectance factor, HDRF, values. Compared to the ASD, the reflectance anisotropy measured with the CE600 provides much higher resolution in terms of directional reflectance (N = 16,020). The hyperangular resolution allows detecting features that were overlooked using the ASD due to its limited number of measurement angles (N = 25). This data set of HDRF further documents variations in the anisotropy of the reflectance of snow and ice with the geometry of observation and illumination conditions and its spectral and spatial scale dependency. Finally, in order to reproduce the hyperangular CE600 reflectance measurements over the entire 400-900 nm spectral range, a regression-based method is proposed to combine the ASD and CE600 measurements. Results confirm that both instruments may be used in synergy to construct a hyperangular and hyperspectral snow and ice reflectance anisotropy data set.

Multichannel system for angular distribution measurements

International Nuclear Information System (INIS)

Burjan, V.; Kroha, V.; Putz, K.

A description is given of the individual blocks of the spectrometric apparatus used for measuring the angular distribution of particle spectra and excitation functions of (d,p) reactions at an electrostatic accelerator and the U-120 M cyclotron, both operating at the Nuclear Physics Institute of the Czechoslovak Academy of Sciences at Rez. Main attention was devoted to attaining maximum energy resolution at a high measurement efficiency, this by installing 8 independent spectrometric chains allowing simultaneous measurement of angular distribution in 8 points of the beam. The semiconductor detectors were cooled to -40 degC to -60 degC, which significantly reduced the level of inherent detector noise. An energy resolution of 13 keV was attained using Tesla detectors at a particle energy of 11 MeV. A brief review of data processing and software is given. (B.S.)

Prospects for γ-ray imaging telescopes

International Nuclear Information System (INIS)

Carter, J.N.; Dean, A.J.; Ramsden, D.

1981-01-01

Apart from the requirement for a new, high angular-resolution gamma-ray telescope for the more precise location of known COS-B gamma-ray sources, there is also a need for another instrument that can be used in a search for the gamma-ray emission from specific X-ray-emitting objects. If there is to be any hope of relating gamma ray emission to specific candidate X-ray objects, then an angular resolution of typically a few minutes of arc is required to resolve adjacent sources in crowded regions of the sky such as the galactic centre. Efforts to improve the angular resolution of track-chamber telescopes are compared. For energies close to 1 MeV telescopes have either used collimators to restrict the field of view or have made use of the kinematics of the Compton scattering process to determine the direction of the incident photon. The use of coded aperture techniques in high angular resolution X-ray astronomy telescopes is reviewed. A practical telescope for astronomy at high energies described by Carter is mentioned. At low energies an imaging telescope could be constructed by making use of position-sensitive detectors initially developed for use in medical physics. Such a telescope is outlined in general terms and its benefits and uses given. (U.K.)

ANGULAR MOMENTUM ACQUISITION IN GALAXY HALOS

International Nuclear Information System (INIS)

Stewart, Kyle R.; Brooks, Alyson M.; Bullock, James S.; Maller, Ariyeh H.; Diemand, Jürg; Wadsley, James; Moustakas, Leonidas A.

2013-01-01

We use high-resolution cosmological hydrodynamic simulations to study the angular momentum acquisition of gaseous halos around Milky-Way-sized galaxies. We find that cold mode accreted gas enters a galaxy halo with ∼70% more specific angular momentum than dark matter averaged over cosmic time (though with a very large dispersion). In fact, we find that all matter has a higher spin parameter when measured at accretion than when averaged over the entire halo lifetime, and is well characterized by λ ∼ 0.1, at accretion. Combined with the fact that cold flow gas spends a relatively short time (1-2 dynamical times) in the halo before sinking to the center, this naturally explains why cold flow halo gas has a specific angular momentum much higher than that of the halo and often forms ''cold flow disks.'' We demonstrate that the higher angular momentum of cold flow gas is related to the fact that it tends to be accreted along filaments.

The X-ray Astronomy Recovery Mission

Science.gov (United States)

Tashiro, M.; Kelley, R.

2017-10-01

On 25 March 2016, the Japanese 6th X-ray astronomical satellite ASTRO-H (Hitomi), launched on February 17, lost communication after a series of mishap in its attitude control system. In response to the mishap the X-ray astronomy community and JAXA analyzed the direct and root cause of the mishap and investigated possibility of a recovery mission with the international collaborator NASA and ESA. Thanks to great effort of scientists, agencies, and governments, the X-ray Astronomy Recovery Mission (XARM) are proposed. The recovery mission is planned to resume high resolution X-ray spectroscopy with imaging realized by Hitomi under the international collaboration in the shortest time possible, simply by focusing one of the main science goals of Hitomi Resolving astrophysical problems by precise high-resolution X-ray spectroscopy'. XARM will carry a 6 x 6 pixelized X-ray micro-calorimeter on the focal plane of an X-ray mirror assembly, and an aligned X-ray CCD camera covering the same energy band and wider field of view, but no hard X-ray or soft gamma-ray instruments are onboard. In this paper, we introduce the science objectives, mission concept, and schedule of XARM.

A lower limit to the accretion disc radius in the low-luminosity AGN NGC 1052 derived from high-angular resolution data

Science.gov (United States)

Reb, Lennart; Fernández-Ontiveros, Juan A.; Prieto, M. Almudena; Dolag, Klaus

2018-05-01

We investigate the central sub-arcsec region of the low-luminosity active galactic nucleus NGC 1052, using a high-angular resolution dataset that covers 10 orders of magnitude in frequency. This allows us to infer the continuum emission within the innermost ˜17 pc around the black hole to be of non-thermal, synchrotron origin and to set a limit to the maximum contribution of a standard accretion disc. Assuming the canonical 10 per cent mass-light conversion efficiency for the standard accretion disc, its inferred accretion power would be too low by one order of magnitude to account for the observed continuum luminosity. We thus introduce a truncated accretion disc and derive a truncation radius to mass-light conversion efficiency relation, which we use to reconcile the inferred accretion power with the continuum luminosity. As a result we find that a truncated disc providing the necessary accretion power must be truncated at rtr ≳ 26 rg, consistent with the inner radius derived from the observations of the Fe Kα line in the X-ray spectrum of this nucleus. This is the first time to derive a limit on the truncation radius of the accretion disc from high-angular resolution data only.

Teaching and Learning Astronomy

Science.gov (United States)

Pasachoff, Jay; Percy, John

2009-07-01

Preface; Part I. Astronomy in the Curriculum Around the World: Preface; 1. Why astronomy is useful and should be included in the school curriculum John R. Percy; 2. Astronomy and mathematics education Rosa M. Ros; 3. Astronomy in the curriculum around the world; 4. Engaging gifted science students through astronomy Robert Hollow; 5. Poster highlights: astronomy in the curriculum around the world; Part II. Astronomy Education Research: Preface; 6. Astronomy education research down under John M. Broadfoot and Ian S. Ginns; 7. A contemporary review of K-16 astronomy education research Janelle M. Bailey and Timothy F. Slater; 8. Implementing astronomy education research Leonarda Fucili; 9. The Astronomy Education Review: report on a new journal Sidney C. Wolff and Andrew Fraknoi; 10. Poster highlights: astronomy education research; Part III. Educating Students: Preface; 11. Textbooks for K-12 astronomy Jay M. Pasachoff; 12. Distance/internet astronomy education David H. McKinnon; 13. Educating students with robotic telescopes - open discussion; 14. Poster highlights - educating students; Part IV. Educating teachers: Preface; 15. Pre-service astronomy education of teachers Mary Kay Hemenway; 16. In-service education of teachers Michèle Gerbaldi; 17. Poster highlights: educating teachers; Part V. Astronomy and Pseudoscience: Preface; 18. Astronomy, pseudoscience and rational thinking Jayant V. Narlikar; 19. Astronomical pseudosciences in North America John R. Percy and Jay M. Pasachoff; Part VI. Astronomy and Culture: Preface; 20. Teaching astronomy in other cultures: archeoastronomy Julieta Fierro; 21. Poster highlights: astronomy and culture; Part VII. Astronomy in Developing Countries: Preface; 22. Astronomy Curriculum for developing countries Case Rijsdijk; 23. Science education resources for the developing countries James C. White II; Part VIII. Public Outreach in Astronomy: Preface; 24. What makes informal education programs successful? Nahide Craig and Isabel

Segmentation of High Angular Resolution Diffusion MRI using Sparse Riemannian Manifold Clustering

Science.gov (United States)

Wright, Margaret J.; Thompson, Paul M.; Vidal, René

2015-01-01

We address the problem of segmenting high angular resolution diffusion imaging (HARDI) data into multiple regions (or fiber tracts) with distinct diffusion properties. We use the orientation distribution function (ODF) to represent HARDI data and cast the problem as a clustering problem in the space of ODFs. Our approach integrates tools from sparse representation theory and Riemannian geometry into a graph theoretic segmentation framework. By exploiting the Riemannian properties of the space of ODFs, we learn a sparse representation for each ODF and infer the segmentation by applying spectral clustering to a similarity matrix built from these representations. In cases where regions with similar (resp. distinct) diffusion properties belong to different (resp. same) fiber tracts, we obtain the segmentation by incorporating spatial and user-specified pairwise relationships into the formulation. Experiments on synthetic data evaluate the sensitivity of our method to image noise and the presence of complex fiber configurations, and show its superior performance compared to alternative segmentation methods. Experiments on phantom and real data demonstrate the accuracy of the proposed method in segmenting simulated fibers, as well as white matter fiber tracts of clinical importance in the human brain. PMID:24108748

NRAO Response to NSF Senior Review of Astronomy Facilities

Science.gov (United States)

2006-11-01

The National Science Foundation's (NSF) Astronomy Senior Review Committee report (pdf file), released today, made major recommendations for restructuring the NSF's ground-based astronomy efforts, including significant changes for the National Radio Astronomy Observatory (NRAO). The committee's report urged that leadership in radio astronomy, including millimeter- and submillimeter-wave observatories, "remain centered at NRAO as it is, by far, the largest radio astronomy organization in the world." The report praised the record of management of NRAO and the scientific capabilities of the Atacama Large Millimeter/submillimeter Array (ALMA), the Expanded Very Large Array (EVLA), the Robert C. Byrd Green Bank Telescope (GBT), and the Very Long Baseline Array (VLBA). However, the report also recommended that some reductions and changes occur at the NRAO by 2011. Specifically, the report recommended that: (a) VLBA operations make a transition to a significant reliance on international funding or risk closure; (b) GBT operations costs be reduced; and (c) NRAO scientific staff costs be reduced. "The Senior Review Committee had the very difficult task of reconciling the needs of current facilities and funding new facilities for the future of astronomy. We appreciate their efforts and look forward to working with the NSF to ensure that the valuable and unique research capabilities of our NRAO telescopes continue to serve the astronomical community," said Dr. Fred K.Y. Lo, NRAO Director. The VLBA provides the greatest angular resolution, or ability to see fine detail, of any telescope in the world, greatly exceeding the capabilities of the Hubble Space Telescope and the future Square Kilometre Array. The committee recognized that, "if the VLBA is closed, a unique capability would likely be lost for decades." "The VLBA is used by scientists from around the world because of its unique capabilities. It has produced landmark research milestones and the committee recognized in its

Misconceptions in Astronomy: Before and After a Constructivist Learning Environment

Science.gov (United States)

Ruzhitskaya, Lanika; Speck, A.

2009-01-01

We present results of a pilot study on college students’ misconceptions in astronomy. The study was conducted on the campus of a Midwestern university among 43 non-science major students enrolled in an introductory astronomy laboratory course. The laboratory course was based on a constructivist learning environment where students learned astronomy by doing astronomy. During the course, students worked with educational simulations created by Project CLEA team and RedShift College Education Astronomy Workbook by Bill Walker as well as were involved in think-pair-share discussions based on Lecture-Tutorials (Prather et al 2008). Several laboratories were prompted by an instructor's brief presentations. On the first and last days of the course students were surveyed on what their beliefs were about causes of the seasons, the moon's apparent size in the sky and its phases, planetary orbits, structure of the solar system, the sun, distant stars, and the nature of light. The majority of the surveys’ questions were based on Neil Comins’ 50 most commonly cited misconceptions. The outcome of the study showed that while students constructed correct understanding of a number of phenomena, they also created a set of new misconceptions. For example, if on the first day of the course, nine out of 43 students knew what caused the seasons on Earth; on the last day of the course, 20 students gained the similar understanding. However, by the end of the course more students believed that smaller planets must rotate faster based on the conservation of angular momentum and Kepler's laws. Our findings suggest that misconceptions pointed out by Neil Comins over a decade ago are still relevant today; and that learning based exclusively on simulations and collaborative group discussions does not necessarily produce the best results, but may set a ground for creating new misconceptions.

Using the Teach Astronomy Website to Enrich Introductory Astronomy Classes

Science.gov (United States)

Hardegree-Ullman, K. K.; Impey, C. D.; Patikkal, A.; Austin, C. L.

2013-04-01

This year we implemented Teach Astronomy as a free online resource to be used as a teaching tool for non-science major astronomy courses and for a general audience interested in the subject. The comprehensive astronomy content of the website includes: an introductory text book, encyclopedia articles, images, two to three minute topical video clips, podcasts, and news articles. Teach Astronomy utilizes a novel technology to cluster, display, and navigate search results, called a Wikimap. We will present an overview of how Teach Astronomy works and how instructors can use it as an effective teaching tool in the classroom. Additionally, we will gather feedback from science instructors on how to improve the features and functionality of the website, as well as develop new assignment ideas using Teach Astronomy.

Astronomy with a home computer

CERN Document Server

Monks, Neale

2005-01-01

Here is a one-volume guide to just about everything computer-related for amateur astronomers! Today's amateur astronomy is inextricably linked to personal computers. Computer-controlled "go-to" telescopes are inexpensive. CCD and webcam imaging make intensive use of the technology for capturing and processing images. Planetarium software provides information and an easy interface for telescopes. The Internet offers links to other astronomers, information, and software. The list goes on and on. Find out here how to choose the best planetarium program: are commercial versions really better than freeware? Learn how to optimise a go-to telescope, or connect it to a lap-top. Discover how to choose the best webcam and use it with your telescope. Create a mosaic of the Moon, or high-resolution images of the planets... Astronomy with a Home Computer is designed for every amateur astronomer who owns a home computer, whether it is running Microsoft Windows, Mac O/S or Linux. It doesn't matter what kind of telescope you...

Astronomy Communication

Science.gov (United States)

Heck, A.; Madsen, C.

2003-07-01

Astronomers communicate all the time, with colleagues of course, but also with managers and administrators, with decision makers and takers, with social representatives, with the news media, and with the society at large. Education is naturally part of the process. Astronomy communication must take into account several specificities: the astronomy community is rather compact and well organized world-wide; astronomy has penetrated the general public remarkably well with an extensive network of associations and organizations of aficionados all over the world. Also, as a result of the huge amount of data accumulated and by necessity for their extensive international collaborations, astronomers have pioneered the development of distributed resources, electronic communications and networks coupled to advanced methodologies and technologies, often much before they become of common world-wide usage. This book is filling up a gap in the astronomy-related literature by providing a set of chapters not only of direct interest to astronomy communication, but also well beyond it. The experts contributing to this book have done their best to write in a way understandable to readers not necessarily hyperspecialized in astronomy nor in communication techniques while providing specific detailed information, as well as plenty of pointers and bibliographic elements. This book will be very useful for researchers, teachers, editors, publishers, librarians, computer scientists, sociologists of science, research planners and strategists, project managers, public-relations officers, plus those in charge of astronomy-related organizations, as well as for students aiming at a career in astronomy or related space science. Link: http://www.wkap.nl/prod/b/1-4020-1345-0

African Cultural Astronomy

CERN Document Server

Holbrook, Jarita C; Medupe, R. Thebe; Current Archaeoastronomy and Ethnoastronomy research in Africa

2008-01-01

Astronomy is the science of studying the sky using telescopes and light collectors such as photographic plates or CCD detectors. However, people have always studied the sky and continue to study the sky without the aid of instruments this is the realm of cultural astronomy. This is the first scholarly collection of articles focused on the cultural astronomy of Africans. It weaves together astronomy, anthropology, and Africa. The volume includes African myths and legends about the sky, alignments to celestial bodies found at archaeological sites and at places of worship, rock art with celestial imagery, and scientific thinking revealed in local astronomy traditions including ethnomathematics and the creation of calendars. Authors include astronomers Kim Malville, Johnson Urama, and Thebe Medupe; archaeologist Felix Chami, and geographer Michael Bonine, and many new authors. As an emerging subfield of cultural astronomy, African cultural astronomy researchers are focused on training students specifically for do...

Astronomy and Politics

Science.gov (United States)

Steele, John M.

The relationship between astronomy and politics is a complex but important part of understanding the practice of astronomy throughout history. This chapter explores some of the ways that astronomy, astrology, and politics have interacted, placing particular focus on the way that astronomy and astrology have been used for political purposes by both people in power and people who wish to influence a ruler's policy. Also discussed are the effects that politics has had on the development of astronomy and, in particular, upon the recording and preservation of astronomical knowledge.

Stability of dislocation structures in copper towards stress relaxation investigated by high angular resolution 3D X-ray diffraction

DEFF Research Database (Denmark)

Jakobsen, Bo; Poulsen, Henning Friis; Lienert, Ulrich

2009-01-01

A 300 µm thick tensile specimen of OFHC copper is subjected to a tensile loading sequence and deformed to a maximal strain of 3.11%. Using the novel three-dimensional X-ray diffraction method High angular resolution 3DXRD', the evolution of the microstructure within a deeply embedded grain....... In contrast to the deformation stages, during each stress relaxation stage, number, size and orientation of subgrains are found to be constant, while a minor amount of clean-up of the microstructure is observed as narrowing of the radial X-ray diffraction line profile. The associated decrease in the width...

Journal of Astrophysics and Astronomy | Indian Academy of Sciences

Indian Academy of Sciences (India)

Therefore, multiwaveband observational efforts with wide fields of view will be the key to progress of transients astronomy from the middle 2020s offering unprecedented deep images and high spatial and spectral resolutions. Radio observations of Gamma Ray Bursts (GRBs) with SKA will uncover not only much fainter ...

Astronomy across cultures the history of non-Western astronomy

CERN Document Server

Xiaochun, Sun

2000-01-01

Astronomy Across Cultures: A History of Non-Western Astronomy consists of essays dealing with the astronomical knowledge and beliefs of cultures outside the United States and Europe. In addition to articles surveying Islamic, Chinese, Native American, Aboriginal Australian, Polynesian, Egyptian and Tibetan astronomy, among others, the book includes essays on Sky Tales and Why We Tell Them and Astronomy and Prehistory, and Astronomy and Astrology. The essays address the connections between science and culture and relate astronomical practices to the cultures which produced them. Each essay is well illustrated and contains an extensive bibliography. Because the geographic range is global, the book fills a gap in both the history of science and in cultural studies. It should find a place on the bookshelves of advanced undergraduate students, graduate students, and scholars, as well as in libraries serving those groups.

High Resolution Adjustable Mirror Control for X-ray Astronomy

Science.gov (United States)

Trolier-McKinstry, Susan

We propose to build and test thin film transistor control circuitry for a new highresolution adjustable X-ray mirror technology. This control circuitry will greatly simplify the wiring scheme to address individual actuator cells. The result will be a transformative improvement for the X-ray Surveyor mission concept: mathematical models, which fit the experimental data quite well, indicate that 0.5 arcsecond imaging is feasible through this technique utilizing thin slumped glass substrates with uncorrected angular resolution of order 5-10 arcseconds. In order to correct for figures errors in a telescope with several square meters of collecting area, millions of actuator cells must be set and held at specific voltages. It is clearly not feasible to do this via millions of wires, each one connected to an actuator. Instead, we propose to develop and test thin-film technology that operates on the same principle as megapixel computer screens. We will develop the technologies needed to build thin film piezoelectric actuators, controlled by thin film ZnO transistors, on flexible polyimide films, and to connect those films to the back surfaces of X-ray mirrors on thin glass substrates without deforming the surface. These technologies represent a promising avenue of the development of mirrors for the X-Ray Surveyor mission concept. Such a telescope will make possible detailed studies of a wide variety of astrophysical sources. One example is the Warm-Hot Intergalactic Medium (WHIM), which is thought to account for a large fraction of the normal matter in the universe but which has not been detected unambiguously to date. Another is the growth of supermassive black holes in the early universe. This proposal supports NASA's goals of technical advancement of technologies suitable for future missions, and training of graduate students.

Teach Astronomy: An Online Resource for Introductory Astronomy Courses and Informal Learners

Science.gov (United States)

Austin, Carmen; Impey, C. D.; Hardegree-Ullman, K.; Patikkal, A.; Ganesan, N.

2013-01-01

Teach Astronomy (www.teachastronomy.com) is a new, free online resource—a teaching tool for non-science major astronomy courses and a reference guide for lifelong learners interested in the subject. Digital content available includes: a comprehensive introductory astronomy textbook by Chris Impey, Wikipedia astronomy articles, images from Astronomy Picture of the Day archives and AstroPix database, two to three minute topical video clips by Chris Impey, podcasts from 365 Days of Astronomy archives, and an RSS feed of astronomy news from Science Daily. Teach Astronomy features an original technology called the Wikimap to cluster, display, and navigate site search results. Motivation behind the development of Teach Astronomy includes steep increases in textbook prices, the rapid adoption by students and the public of digital resources, and the modern capabilities of digital technology. Recent additions to Teach Astronomy include: AstroPix images—from some of the most advanced observatories and complete with metadata, mobile device functionality, links to WikiSky where users can see the location of astronomical objects in the sky, and end of chapter textbook review questions. Next in line for development are assignments for classroom use. We present suggestions for utilizing the rich content and features of the web site.

Philippine Astronomy Convention 2009 Abstract: Program Offerings in Astronomy in the Philippines

Science.gov (United States)

Torres, J. R. F.

2009-03-01

The formal academic programs in Astronomy of the Rizal Technological University are the first such programs in the Philippines. The Master of Science in Astronomy program is envisioned to provide the student with a wide range of knowledge in many areas of Astronomy, leaning towards the descriptive aspects of knowledge. The student will choose the field or research most suitable to his or her interests. Three of these researches done while enrolled in the program, and even researches completed before the student actually enrolled in the program, may be considered as his or her thesis. The program suits professionals in all persuasions who wish to study Astronomy either for professional advancement or plainly for the love of the science or for intellectual satisfaction. Non-science majors can enroll. In 2008, the RTU Graduate School decided to ladderize the MS program and the Graduate Diploma in Astronomy was designed. This program is suited for science educators, astronomy lecturers and entrepreneurs, members of astronomical societies, and plain astronomy enthusiasts who like to gain in-depth knowledge in the most important aspects of astronomy. A bachelor's degree in any field is required. The program can be finished in two semesters and one summer. If the student opts to continue in the MS in Astronomy program, all the courses he or she has earned in the Diploma will be credited. The Bachelor of Science in Astronomy Technology is an intensive baccalaureate degree program designed to prepare students to become future research scientists and technologists in the field of Astronomy. The BS in Astronomy Technology is a cross-fertilized program, integrating interrelated sciences, such as engineering, geology, remote sensing, physics, atmospheric and environmental science, biology and biochemistry, and even philosophy and entrepreneurship into the study. Thus, the B.S. in Astronomy Technology program gives the student excellent job opportunities in many fields.

Introducing Astronomy Related Research into Non-Astronomy Courses

Science.gov (United States)

Walker, Douglas

The concern over the insufficient number of students choosing to enter the science and engineering fields has been discussed and documented for years. While historically addressed at the national level, many states are now recognizing that the lack of a highly-skilled technical workforce within their states' borders has a significant effect on their economic health. Astronomy, as a science field, is no exception. Articles appear periodically in the most popular astronomy magazines asking the question, "Where are the young astronomers?" Astronomy courses at the community college level are normally restricted to introductory astronomy I and II level classes that introduce the student to the basics of the night sky and astronomy. The vast majority of these courses is geared toward the non-science major and is considered by many students to be easy and watered down courses in comparison to typical physics and related science courses. A majority of students who enroll in these classes are not considering majors in science or astronomy since they believe that science is "boring and won't produce any type of career for them." Is there any way to attract students? This paper discusses an approach being undertaken at the Estrella Mountain Community College to introduce students in selected mathematics courses to aspects of astronomy related research to demonstrate that science is anything but boring. Basic statistical techniques and understanding of geometry are applied to a large virgin data set containing the magnitudes and phase characteristics of sets of variable stars. The students' work consisted of developing and presenting a project that explored analyzing selected aspects of the variable star data set. The description of the data set, the approach the students took for research projects, and results from a survey conducted at semester's end to determine if student's interest and appreciation of astronomy was affected are presented. Using the data set provided, the

Astronomy in Mozambique

Science.gov (United States)

Ribeiro, Valério A. R. M.; Paulo, Cláudio M.

2015-03-01

We present the state of Astronomy in Mozambique and how it has evolved since 2009 following the International Year of Astronomy. Activities have been lead by staff at University Eduardo Mondlane and several outreach activities have also flourished. In 2010 the University introduced its first astronomy module, Introduction to Astronomy and Astrophysics, for the second year students in the Department of Physics. The course has now produced the first students who will be graduating in late 2012 with some astronomy content. Some of these students will now be looking for further studies and those who have been keen in astronomy have been recommended to pursue this as a career. At the university level we have also discussed on the possibility to introduce a whole astronomy course by 2016 which falls well within the HCD that the university is now investing in. With the announcement that the SKA will be split between South Africa with its partner countries (including Mozambique), and Australia we have been working closely with the Ministry of Science and Technology to make astronomy a priority on its agenda. In this respect, an old telecommunications antenna is being converted by the South Africa SKA Project Office, and donated to Mozambique for educational purposes. It will be situated in Maluana, Mozambique.

Sub-Airy disk angular resolution with high dynamic range in the near-infrared

Directory of Open Access Journals (Sweden)

Richichi A.

2011-07-01

Full Text Available Lunar occultations (LO are a simple and effective high angular resolution method, with minimum requirements in instrumentation and telescope time. They rely on the analysis of the diffraction fringes created by the lunar limb. The diffraction phenomen occurs in space, and as a result LO are highly insensitive to most of the degrading effects that limit the performance of traditional single telescope and long-baseline interferometric techniques used for direct detection of faint, close companions to bright stars. We present very recent results obtained with the technique of lunar occultations in the near-IR, showing the detection of companions with very high dynamic range as close as few milliarcseconds to the primary star. We discuss the potential improvements that could be made, to increase further the current performance. Of course, LO are fixed-time events applicable only to sources which happen to lie on the Moon’s apparent orbit. However, with the continuously increasing numbers of potential exoplanets and brown dwarfs beign discovered, the frequency of such events is not negligible. I will list some of the most favorable potential LO in the near future, to be observed from major observatories.

The 1.5 meter solar telescope GREGOR

Czech Academy of Sciences Publication Activity Database

Schmidt, W.; von der Lühe, O.; Volkmer, R.; Denker, C.; Solanki, S.K.; Balthasar, H.; Bello González, N.; Berkefeld, T.; Collados Vera, M.; Fischer, A.; Halbgewachs, C.; Heidecke, F.; Hofmann, A.; Kneer, F.; Lagg, A.; Nicklas, H.; Popow, E.; Puschmann, K.G.; Schmidt, D.; Sigwarth, M.; Sobotka, Michal; Soltau, D.; Staude, J.; Strassmeier, K.G.; Waldmann, T.A.

2012-01-01

Roč. 333, č. 9 (2012), s. 796-809 ISSN 0004-6337 Institutional support: RVO:67985815 Keywords : high angular resolution * magnetic fields * telescopes Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 1.399, year: 2012

Astronomy Education in Morocco - New Project for Implementing Astronomy in High Schools

Science.gov (United States)

Darhmaoui, H.; Loudiyi, K.

2006-08-01

Astronomy education in Morocco, like in many developing countries, is not well developed and lacks the very basics in terms of resources, facilities and research. In 2004, the International Astronomical Union (IAU) signed an agreement of collaboration with Al Akhawayn University in Ifrane to support the continued, long-term development of astronomy and astrophysics in Morocco. This is within the IAU program "Teaching for Astronomy Development" (TAD). The initial focus of the program concentrated exclusively on the University's Bachelor of Science degree program. Within this program, and during two years, we were successful in providing adequate astronomy training to our physics faculty and few of our engineering students. We also offered our students and community general astronomy background through courses, invited talks and extra curricular activities. The project is now evolving towards a wider scope and seeks promoting astronomy education at the high school level. It is based on modules from the Hands on Universe (HOU) interactive astronomy program. Moroccan students will engage in doing observational astronomy from their PCs. They will have access to a world wide network of telescopes and will interact with their peers abroad. Through implementing astronomy education at this lower age, we foresee an increasing interest among our youth not only in astronomy but also in physics, mathematics, and technology. The limited astronomy resources, the lack of teachers experience in the field and the language barrier are amongst the difficulties that we'll be facing in achieving the objectives of this new program.

Current Status of the IAU Working Group for Numerical Standards of Fundamental Astronomy

National Research Council Canada - National Science Library

Luzum, B; Capitaine, N; Fienga, A; Folkner, W; Fukushima, T; Hilton, J; Hohenkerk, C; Krasinsky, G; Petit, G; Pitjeva, E; Soffel, M; Wallace, P

2007-01-01

...) for Numerical Standards of Fundamental Astronomy. The goal of the WG are to update "IAU Current Best Estimates" conforming with IAU Resolutions, the International Earth Rotation and Reference System Service (IERS...

Theoretical evaluation of the Doppler broadening contribution to the angular resolution in CdZnTe Compton scattering detector

International Nuclear Information System (INIS)

Diaz Garcia, A.; Cabal Rodriguez, A.E.; Rubio Rodriguez, J. A.; Salicio Diez, J.; Perez Morales, J.M.; Vela Morales, O.; Willmott Zappacosta, C.; Van Espen, P.

2011-01-01

Electronically collimated Compton Cameras have been tested in Single Photon Emission Tomography (SPECT) systems instead of mechanically collimated gamma detectors in order to improve their limited sensitivity. One of the main factors that contribute to the worsening of the angular resolution and thus to the deterioration of the system spatial resolution is Doppler broadening. Double differential Klein-Nishina equation is used to consider the random movement of electron inside the crystal. It is important to perform this analysis for each particular material because is difficult to infer one simple Doppler broadening dependency of the atomic number Z. In high Z materials the internal electrons are strongly linked to the nucleus and therefore there can be found high momentums, but they represent just a small portion of the electrons that suffers Compton scattering. This work estimates the influence of the Doppler broadening in CdZnTe semiconductor for different incoming photon energies. For this means there are analyzed main Compton broadening processes in semiconductor Cd 0,8 Zn 0,2 Te with density ρ=5,85g/cm 3 . (Author)

Teach Astronomy: An Online Textbook for Introductory Astronomy Courses and Resources for Informal Learners

Science.gov (United States)

Hardegree-Ullman, Kevin; Impey, C. D.; Patikkal, A.

2012-05-01

This year we implemented Teach Astronomy (www.teachastronomy.com) as a free online resource to be used as a teaching tool for non-science major astronomy courses and for a general audience interested in the subject. The comprehensive content includes: an introductory astronomy text book by Chris Impey, astronomy articles on Wikipedia, images from the Astronomy Picture of the Day, two to three minute topical video clips by Chris Impey, podcasts from 365 Days of Astronomy, and astronomy news from Science Daily. Teach Astronomy utilizes a novel technology to cluster, display, and navigate search results, called a Wikimap. Steep increases in textbook prices and the unique capabilities of emerging web technology motivated the development of this free online resource. Recent additions to Teach Astronomy include: images and diagrams for the textbook articles, mobile device implementation, and suggested homework assignments for instructors that utilize recent discoveries in astronomy. We present an overview of how Teach Astronomy has been implemented for use in the classroom and informal settings, and suggestions for utilizing the rich content and features of the web site.

Astronomy for Development: Path to Global Impact

Science.gov (United States)

Venugopal, R.; Govender, K.; Grant, E.

2017-07-01

The IAU established its Office of Astronomy for Development in 2011 in Cape Town, South Africa, in partnership with the South African National Research Foundation, and hosted at the South African Astronomical Observatory. The primary purpose of the office has been to implement the IAU's decadal strategic plan which aims to use astronomy to stimulate education and development globally. Since its inception there have been nine regional offices established, including one in the Latin American region which focuses on Andean countries. Following a very positive external review in 2015, as well as a supportive resolution by the 2015 IAU General Assembly to continue the work of the office, the OAD is now in a position to move beyond the setting up of structures to a more intensive effort aimed at measuring and delivering programmes with broader global impact.

Armenian Cultural Astronomy

Science.gov (United States)

Farmanyan, S. V.; Mickaelian, A. M.

2015-07-01

Cultural Astronomy is the reflection of sky events in various fields of nations' culture. In foreign literature this field is also called "Astronomy in Culture" or "Astronomy and Culture". Cultural astronomy is the set of interdisciplinary fields studying the astronomical systems of current or ancient societies and cultures. It is manifested in Religion, Mythology, Folklore, Poetry, Art, Linguistics and other fields. In recent years, considerable attention has been paid to this sphere, particularly international organizations were established, conferences are held and journals are published. Armenia is also rich in cultural astronomy. The present paper focuses on Armenian archaeoastronomy and cultural astronomy, including many creations related to astronomical knowledge; calendars, rock art, mythology, etc. On the other hand, this subject is rather poorly developed in Armenia; there are only individual studies on various related issues (especially many studies related to Anania Shirakatsi) but not coordinated actions to manage this important field of investigation.

On the angular momentum in star formation

International Nuclear Information System (INIS)

Horedt, G.P.

1978-01-01

The author discusses the rotation of interstellar clouds which are in a stage immediately before star formation. Cloud collisions seem to be the principal cause of the observed rotation of interstellar clouds. The rotational motion of the clouds is strongly influenced by turbulence. Theories dealing with the resolution of the angular momentum problem in star formation are classified into five major groups. The old idea that the angular momentum of an interstellar cloud passes during star formation into the angular momentum of double star systems and/or circumstellar clouds, is developed. It is suggested that a rotating gas cloud contracts into a ring-like structure which fragments into self-gravitating subcondensations. By collisions and gas accretion these subcondensations accrete into binary systems surrounded by circumstellar clouds. Using some rough approximations the authors find analytical expressions for the semi-major axis of the binary system and for the density of the circumstellar clouds as a function of the initial density and of the initial angular velocity of an interstellar cloud. The obtained values are well within the observational limits. (Auth.)

The 2014 ALMA Long Baseline Campaign: An Overview

Czech Academy of Sciences Publication Activity Database

Fomalont, E.B.; Vlahakis, C.; Corder, S.; Remijan, A.; Barkats, D.; Lucas, R.; Hunter, T.R.; Brogan, C.L.; Asaki, Y.; Matsushita, S.; Dent, W.R.F.; Hills, R.E.; Phillips, N.; Richards, A.M.S.; Cox, P.; Amestica, R.; Broguiere, D.; Cotton, W.; Hales, A.S.; Hiriart, R.; Hirota, A.; Hodge, J.A.; Impellizzeri, C.M.V.; Kern, J.; Kneissl, R.; Liuzzo, E.; Marcelino, N.; Marson, R.; Mignano, A.; Nakanishi, K.; Nikolic, B.; Perez, J.E.; Perez, L.M.; Toledo, I.; Bárta, Miroslav; Jáchym, Pavel; Karlický, Marian; Kraus, Michaela; Kunneriath, Devaky

2015-01-01

Roč. 808, č. 1 (2015), L1/1-L1/11 ISSN 2041-8205 Institutional support: RVO:67985815 Keywords : interferometers * submillimeter * high angular resolution Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 5.487, year: 2015

The Astronomy Workshop

Science.gov (United States)

Hamilton, D. P.; Asbury, M. L.; Proctor, A.

2001-12-01

The Astronomy Workshop (http://janus.astro.umd.edu) is an interactive online astronomy resource developed, and maintained at the University of Maryland, for use by students, educators and the general public. The Astronomy Workshop has been extensively tested and used successfully at many different levels, including High School and Junior High School science classes, University introductory astronomy courses, and University intermediate and advanced astronomy courses. Some topics currently covered in the Astronomy Workshop are: Animated Orbits of Planets and Moons: The orbits of the nine planets and 91 known planetary satellites are shown in animated, to-scale drawings. The orbiting bodies move at their correct relative speeds about their parent, which is rendered as an attractive, to-scale gif image. Solar System Collisions: This most popular of our applications shows what happens when an asteroid or comet with user-defined size and speed impacts a given planet. The program calculates many effects, including the country impacted (if Earth is the target), energy of the explosion, crater size, magnitude of the planetquake generated. It also displays a relevant image (e.g. terrestrial crater, lunar crater, etc.). Planetary and Satellite Data Calculators: These tools allow the user to easily calculate physical data for all of the planets or satellites simultaneously, making comparison very easy. Orbital Simulations: These tools allow the student to investigate different aspects of the three-body problem of celestial mechanics. Astronomy Workshop Bulletin Board: Get innovative teaching ideas and read about in-class experiences with the Astronomy Workshop. Share your ideas with other educators by posting on the Bulletin Board. Funding for the Astronomy Workshop is provided by the National Science Foundation.

Angular integration and inter-projection correlation effects in CT reconstruction

International Nuclear Information System (INIS)

Crawford, C.R.; Pele, N.J.

1987-01-01

CT reconstruction algorithms require snap-shot projections of an object. In order to minimize scan times, CT scanners rotate continuously which, in turn, prevents the acquisition of snap-shot projections. Acquired projections are integrals over angular position and may be correlated inter-projection. This paper shows that angular integration and inter-projection correlation introduce a radially dependent degradation of the spatial resolution and cause the image noise to vary non-linearly with radial position

Fundamental Astronomy

CERN Document Server

Karttunen, Hannu; Oja, Heikki; Poutanen, Markku; Donner, Karl Johan

2007-01-01

Fundamental Astronomy gives a well-balanced and comprehensive introduction to the topics of classical and modern astronomy. While emphasizing both the astronomical concepts and the underlying physical principles, the text provides a sound basis for more profound studies in the astronomical sciences. The fifth edition of this successful undergraduate textbook has been extensively modernized and extended in the parts dealing with the Milky Way, extragalactic astronomy and cosmology as well as with extrasolar planets and the solar system (as a consequence of recent results from satellite missions and the new definition by the International Astronomical Union of planets, dwarf planets and small solar-system bodies). Furthermore a new chapter on astrobiology has been added. Long considered a standard text for physical science majors, Fundamental Astronomy is also an excellent reference and entrée for dedicated amateur astronomers.

Greek astronomy

CERN Document Server

Heath, Sir Thomas L

2011-01-01

Astronomy as a science began with the Ionian philosophers, with whom Greek philosophy and mathematics also began. While the Egyptians and Babylonians had accomplished much of astronomical worth, it remained for the unrivalled speculative genius of the Greeks, in particular, their mathematical genius, to lay the foundations of the true science of astronomy. In this classic study, a noted scholar discusses in lucid detail the specific advances made by the Greeks, many of whose ideas anticipated the discoveries of modern astronomy.Pythagoras, born at Samos about 572 B.C., was probably the first

Space and astronomy

CERN Document Server

Kirkland, Kyle

2010-01-01

Some daring explorers like to study distant frontiers by venturing out into them, but others prefer to study them by bringing them, or representative samples, a little closer to the lab. Both options are pursued in the fields of space and astronomy. Space exploration and astronomy are intricately linked and are examined in-depth in this guide. Dedicated to the scientists who explore the frontiers of space and astronomy-and the results of their unfamiliar findings-each chapter in Space and Astronomy explores one of the frontiers of this science. The development of technology, such as rocket pro

Spatial Angular Compounding Technique for H-Scan Ultrasound Imaging.

Science.gov (United States)

Khairalseed, Mawia; Xiong, Fangyuan; Kim, Jung-Whan; Mattrey, Robert F; Parker, Kevin J; Hoyt, Kenneth

2018-01-01

H-Scan is a new ultrasound imaging technique that relies on matching a model of pulse-echo formation to the mathematics of a class of Gaussian-weighted Hermite polynomials. This technique may be beneficial in the measurement of relative scatterer sizes and in cancer therapy, particularly for early response to drug treatment. Because current H-scan techniques use focused ultrasound data acquisitions, spatial resolution degrades away from the focal region and inherently affects relative scatterer size estimation. Although the resolution of ultrasound plane wave imaging can be inferior to that of traditional focused ultrasound approaches, the former exhibits a homogeneous spatial resolution throughout the image plane. The purpose of this study was to implement H-scan using plane wave imaging and investigate the impact of spatial angular compounding on H-scan image quality. Parallel convolution filters using two different Gaussian-weighted Hermite polynomials that describe ultrasound scattering events are applied to the radiofrequency data. The H-scan processing is done on each radiofrequency image plane before averaging to get the angular compounded image. The relative strength from each convolution is color-coded to represent relative scatterer size. Given results from a series of phantom materials, H-scan imaging with spatial angular compounding more accurately reflects the true scatterer size caused by reductions in the system point spread function and improved signal-to-noise ratio. Preliminary in vivo H-scan imaging of tumor-bearing animals suggests this modality may be useful for monitoring early response to chemotherapeutic treatment. Overall, H-scan imaging using ultrasound plane waves and spatial angular compounding is a promising approach for visualizing the relative size and distribution of acoustic scattering sources. Copyright © 2018 World Federation for Ultrasound in Medicine and Biology. Published by Elsevier Inc. All rights reserved.

The next-generation infrared astronomy mission SPICA under the new framework

NARCIS (Netherlands)

Nakagawa, Takao; Shibai, Hiroshi; Onaka, Takashi; Matsuhara, Hideo; Kaneda, Hidehiro; Kawakatsu, Yasuhiro; Roelfsema, Peter

We present the current status of SPICA (Space Infrared Telescope for Cosmology and Astrophysics), which is a mission optimized for mid- and far-infrared astronomy with a cryogenically cooled 3.2 m telescope. SPICA is expected to achieve high spatial resolution and unprecedented sensitivity in the

GREGOR solar telescope: Design and status

Czech Academy of Sciences Publication Activity Database

Volkmer, R.; von der Lühe, O.; Denker, C.; Solanki, S.K.; Balthasar, H.; Berkefeld, T.; Caligari, P.; Collados Vera, M.; Fischer, A.; Halbgewachs, C.; Heidecke, F.; Hofmann, A.; Klvaňa, Miroslav; Kneer, F.; Lagg, A.; Popow, E.; Schmidt, D.; Schmidt, W.; Sobotka, Michal; Soltau, D.; Strassmeier, K.G.

2010-01-01

Roč. 331, č. 6 (2010), s. 624-627 ISSN 0004-6337 Institutional research plan: CEZ:AV0Z10030501 Keywords : instrumentation * adaptive optics * high angular resolution Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 0.842, year: 2010

The photon angular momentum controversy: Resolution of a conflict between laser optics and particle physics

Energy Technology Data Exchange (ETDEWEB)

Leader, Elliot, E-mail: e.leader@imperial.ac.uk

2016-05-10

The claim some years ago, contrary to all textbooks, that the angular momentum of a photon (and gluon) can be split in a gauge-invariant way into an orbital and spin term, sparked a major controversy in the Particle Physics community, exacerbated by the realization that many different forms of the angular momentum operators are, in principle, possible. A further cause of upset was the realization that the gluon polarization in a nucleon, a supposedly physically meaningful quantity, corresponds only to the gauge-variant gluon spin derived from Noether's theorem, evaluated in a particular gauge. On the contrary, Laser Physicists have, for decades, been happily measuring physical quantities which correspond to photon orbital and spin angular momentum evaluated in a particular gauge. This paper reconciles the two points of view, and shows that it is the gauge invariant version of the canonical angular momentum which agrees with the results of a host of laser optics experiments.

Quantum entanglement of high angular momenta.

Science.gov (United States)

Fickler, Robert; Lapkiewicz, Radek; Plick, William N; Krenn, Mario; Schaeff, Christoph; Ramelow, Sven; Zeilinger, Anton

2012-11-02

Single photons with helical phase structures may carry a quantized amount of orbital angular momentum (OAM), and their entanglement is important for quantum information science and fundamental tests of quantum theory. Because there is no theoretical upper limit on how many quanta of OAM a single photon can carry, it is possible to create entanglement between two particles with an arbitrarily high difference in quantum number. By transferring polarization entanglement to OAM with an interferometric scheme, we generate and verify entanglement between two photons differing by 600 in quantum number. The only restrictive factors toward higher numbers are current technical limitations. We also experimentally demonstrate that the entanglement of very high OAM can improve the sensitivity of angular resolution in remote sensing.

Journal of Astrophysics and Astronomy | Indian Academy of Sciences

Indian Academy of Sciences (India)

2016-01-27

Jan 27, 2016 ... https://www.ias.ac.in/article/fulltext/joaa/036/04/0427-0432 ... High angular resolution spectroscopy obtained with the Hubble Space Telescope (HST) ... In the present contribution, high quality spectra obtained with the Space ...

Astronomy Enrollments and Degrees: Results from the 2012 Survey of Astronomy Enrollments and Degrees. Focus On

Science.gov (United States)

Mulvey, Patrick; Nicholson, Starr

2014-01-01

Interest in astronomy degrees in the U.S. remains strong, with astronomy enrollments at or near all-time highs for the 2012-13 academic year. The total number of students taking an introductory astronomy course at a degree-granting physics or astronomy department is approaching 200,000. Enrollments in introductory astronomy courses have been…

Astronomy at the frontiers of science

CERN Document Server

2011-01-01

Astronomy is by nature an interdisciplinary activity: it involves mathematics, physics, chemistry and biology. Astronomers use (and often develop) the latest technology, the fastest computers and the most refined software.  In this book twenty-two leading scientists from nine countries talk about how astronomy interacts with these other sciences. They describe modern instruments used in astronomy and the relations between astronomy and technology, industry, politics and philosophy. They also discuss what it means to be an astronomer, the history of astronomy, and the place of astronomy in society today.   The book contains twenty chapters grouped in four parts: ASTRONOMY AND PHYSICS discusses the place of astronomy among various branches of (mostly high-energy) physics. ASTRONOMY IN SOCIETY describes not only the historical context of astronomy, but issues facing astronomers today, including funding, planning, worldwide collaboration and links with industry. THE TOOLS OF OBSERVATION AND THE PROFESSION OF AS...

The Future of Space Astronomy.

Science.gov (United States)

Field, George B.

1984-01-01

Discusses various aspects of space astronomy, considering advantages, the space telescope and ground-based astronomy, an orbiting astrophysics facility, solar physics, and other areas. Indicates that earth-based astronomy will continue to be carried out there and space astronomy will be limited to observations that can be carried out only from…

School-Based Extracurricular Astronomy

Science.gov (United States)

Stanger, Jeffrey J.

2010-01-01

The International Year of Astronomy in 2009 focused considerable public attention on Astronomy and generated valuable resources for educators. These activities are an effective vehicle for promoting Science to students and to the wider school community. The most engaging practical astronomy activities are best delivered with sustained support from…

Probing region-specific microstructure of human cortical areas using high angular and spatial resolution diffusion MRI.

Science.gov (United States)

Aggarwal, Manisha; Nauen, David W; Troncoso, Juan C; Mori, Susumu

2015-01-15

Regional heterogeneity in cortical cyto- and myeloarchitecture forms the structural basis of mapping of cortical areas in the human brain. In this study, we investigate the potential of diffusion MRI to probe the microstructure of cortical gray matter and its region-specific heterogeneity across cortical areas in the fixed human brain. High angular resolution diffusion imaging (HARDI) data at an isotropic resolution of 92-μm and 30 diffusion-encoding directions were acquired using a 3D diffusion-weighted gradient-and-spin-echo sequence, from prefrontal (Brodmann area 9), primary motor (area 4), primary somatosensory (area 3b), and primary visual (area 17) cortical specimens (n=3 each) from three human subjects. Further, the diffusion MR findings in these cortical areas were compared with histological silver impregnation of the same specimens, in order to investigate the underlying architectonic features that constitute the microstructural basis of diffusion-driven contrasts in cortical gray matter. Our data reveal distinct and region-specific diffusion MR contrasts across the studied areas, allowing delineation of intracortical bands of tangential fibers in specific layers-layer I, layer VI, and the inner and outer bands of Baillarger. The findings of this work demonstrate unique sensitivity of diffusion MRI to differentiate region-specific cortical microstructure in the human brain, and will be useful for myeloarchitectonic mapping of cortical areas as well as to achieve an understanding of the basis of diffusion NMR contrasts in cortical gray matter. Copyright © 2014 Elsevier Inc. All rights reserved.

Highschool astronomy research workshop in Thailand and how it transforms Thai astronomy education

Science.gov (United States)

Tangmatitham, Matipon

2017-01-01

The National Astronomical Research Institute of Thailand (NARIT) have launched the program "Advance Teacher Training Workshop" that aims to introduce both the students and astronomy teacher alike to the nature of critical thinking in science via hands on experience in astronomy projects. Students and accompanying teachers are participated in 5 days workshop in which each of them must select an individual astronomy research project. The project is then carried out on their own for the next 6 months, after which their works are presented in a conference. Progress is monitored and extra aid is delivered as needed via the use of social media. Over a hundred projects have been completed under this program. Follow up study have suggests that this workshop has shown to be quite successful at improving critical thinking skills in participants. As the program became more popular, other schools began to follow. To support the growing interest, we have also launched the "Thai Astronomical Society: student session", a highschool astronomy conference for anyone who participated or interested in astronomy related projects. Via these stages we are able to secure a permanent foothold in Thai astronomy education and inspire new generations to participate in astronomy projects.

Adaptive Angular Sampling for SPECT Imaging

OpenAIRE

Li, Nan; Meng, Ling-Jian

2011-01-01

This paper presents an analytical approach for performing adaptive angular sampling in single photon emission computed tomography (SPECT) imaging. It allows for a rapid determination of the optimum sampling strategy that minimizes image variance in regions-of-interest (ROIs). The proposed method consists of three key components: (a) a set of close-form equations for evaluating image variance and resolution attainable with a given sampling strategy, (b) a gradient-based algor...

Astronomy Landscape in Africa

Science.gov (United States)

Nemaungani, Takalani

2015-01-01

The vision for astronomy in Africa is embedded in the African Space Policy of the African Union in early 2014. The vision is about positioning Africa as an emerging hub for astronomy sciences and facilities. Africa recognized the need to take advantage of its natural resource, the geographical advantage of the clear southern skies and pristine sites for astronomy. The Pan African University (PAU) initiative also presents an opportunity as a post-graduate training and research network of university nodes in five regions of Africa and supported by the African Union. The Southern African node based in South Africa concentrates on space sciences which also includes astronomy. The PAU aims to provide the opportunity for advanced graduate training and postgraduate research to high-performing African students. Objectives also include promoting mobility of students and teachers and harmonizing programs and degrees.A number of astronomy initiatives have burgeoned in the Southern African region and these include the Southern Africa Largest Optical Telescope (SALT), HESS (High Energy Stereoscopic System), the SKA (Square Kilometre Array) and the AVN (African Very Long Baseline Interferometer Network). There is a growing appetite for astronomy sciences in Africa. In East Africa, the astronomy community is well organized and is growing - the East African Astronomical society (EAAS) held its successful fourth annual conference since 2010 on 30 June to 04 July 2014 at the University of Rwanda. Centred around the 'Role of Astronomy in Socio-Economic Transformation,' this conference aimed at strengthening capacity building in Astronomy, Astrophysics and Space Science in general, while providing a forum for astronomers from the region to train young and upcoming scientists.

Planet Formation Imager (PFI) : science vision and key requirements

NARCIS (Netherlands)

Kraus, S.; Monnier, J.D.; Ireland, M.J.; Duchene, G.; Espaillat, C.; Honig, S.; Juhasz, A.; Mordasini, C.; Olofsson, J.; Paladini, C.; Stassun, K.; Turner, N.; Vasisht, G.; Harries, T.J.; Bate, M.R.; Gonzalez, J-F.; Matter, A.; Zhu, Z.; Panic, O.; Regaly, Z.; Morbidelli, A.; Meru, F.; Wolf, S.; Ilee, J.; Berger, J-P.; Zhao, M.; Kral, Q.; Morlok, A.; Bonsor, A.; Ciardi, D.; Kane, S.R.; Kratter, K.; Laughlin, G.; Pepper, J.; Raymond, S.; Labadie, L.; Nelson, R.P.; Weigelt, G.; Brummelaar, ten T.; Pierens, A.; Oudmaijer, R.; Kley, W.; Pope, B.; Jensen, E.L.N.; Bayo, A.; Smith, M.; Boyajian, T.; Quiroga-Nunez, L.H.; Millan-Gabet, R.; Chiavassa, A.; Gallenne, A.; Reynolds, M.; Wit, de W-J.; Wittkowski, M.; Millour, F.; Gandhi, P.; Ramos, A. C.; Alonso, H. A.; Packham, C.; Kishimoto, M.; Tristram, K.R.W.; Pott, J.-U.; Surdej, J.; Buscher, D.; Haniff, C.; Lacour, S.; Petrov, R.; Ridgway, S.; Tuthill, P.; Belle, van G.; Armitage, P.; Baruteau, C.; Benisty, M.; Bitsch, B.; Paardekooper, S-J.; Pinte, C.; Masset, F.; Rosotti, G.P.

2016-01-01

The Planet Formation Imager (PFI) project aims to provide a strong scientific vision for ground-based optical astronomy beyond the upcoming generation of Extremely Large Telescopes. We make the case that a breakthrough in angular resolution imaging capabilities is required in order to unravel the

Angular distribution of atoms ejected by laser ablation of different metals

International Nuclear Information System (INIS)

Konomi, I.; Motohiro, T.; Asaoka, T.

2009-01-01

Angular distributions of 13 different metals ejected by laser ablation using fourth harmonics (wavelength=266 nm) of neodymium doped yttrium aluminum garnet laser and a fluence close to near-threshold value (2.3 J/cm 2 ) have been investigated with a high angular resolution. The angular distribution which is characterized by the exponent n of cos n θ distribution showed very broad range of values between 3 and 24 for different metals. A simple relation that the exponent n is proportional to the square root of particle atomic weight as reported previously has not been observed. Instead, a general trend has been found that the metals with higher sublimation energy such as Ta and Zr show narrower angular distribution than those with lower sublimation energy such as Sn and In. While the sublimation energy of metals has a great influence on the angular distribution of ejected atoms, a simple consideration suggests that their thermal conductivity and specific heat have little effect on it.

End of the Golden Age for X-ray Astronomy: Technical and Fiscal Challenges

Science.gov (United States)

Elvis, Martin

2012-09-01

Golden Ages don't last much more than 50 years (viz. Athens 4th century BCE, Renaissance Italy, Dutch Golden Age) - that's why they're golden. X-ray astronomy is now 50 years old. Should we expect it to continue to flourish? Or is this the end of our Golden Age? Technologically there is tremendous promise. New optics and detectors are set to deliver great improvements along all axes: collecting area, angular and spectral resolution, field of view, polarimetry. To be optimal along a given axis, missions should not try to combine all these improvements in a single mission. Hence specialized missions of modest size (similar to NASA's Explorer class) should be pursued world-wide. Multiple missions also support a wide, varied, and creative community, not only of observers but also of instrument builders, operations staff and data/archive developers. All are necessary for a healthy field. We should encourage our agencies to adopt vigorous modest-mission programs, and to encourage open access to promote intellectual creativity. But some axes are almost certainly out of reach for Explorer-class missions. Most likely equaling or bettering Chandra angular resolution with larger area will require an Observatory-class, flagship, mission. While the technology is promising, the world-wide prospects for such a mission are grim. This is not merely the result of current economic woes, although they have brought the crisis to a head. Each generation of mission has to be an order of magnitude better than its predecessor in order to win funding. But to achieve this costs go up by a factor of a few each time. The progression: rockets - UHURU - Einstein - Chandra illustrates this clearly. The same exponentiation is evident in UV/visible astronomy and, perhaps, in Mars exploration. We have now hit the "funding wall" where each flagship mission costs so much that they pop into politicians notice. JWST is now a budget line item in the US, a precarious position previously held by the

Affordable and Lightweight High-Resolution X-ray Optics for Astronomical Missions

Science.gov (United States)

Zhang, W. W.; Biskach, M. P.; Bly, V. T.; Carter, J. M.; Chan, K. W.; Gaskin, J. A.; Hong, M.; Hohl, B. R.; Jones, W. D.; Kolodziejczak, J. J.

2014-01-01

Future x-ray astronomical missions require x-ray mirror assemblies that provide both high angular resolution and large photon collecting area. In addition, as x-ray astronomy undertakes more sensitive sky surveys, a large field of view is becoming increasingly important as well. Since implementation of these requirements must be carried out in broad political and economical contexts, any technology that meets these performance requirements must also be financially affordable and can be implemented on a reasonable schedule. In this paper we report on progress of an x-ray optics development program that has been designed to address all of these requirements. The program adopts the segmented optical design, thereby is capable of making both small and large mirror assemblies for missions of any size. This program has five technical elements: (1) fabrication of mirror substrates, (2) coating, (3) alignment, (4) bonding, and (5) mirror module systems engineering and testing. In the past year we have made progress in each of these five areas, advancing the angular resolution of mirror modules from 10.8 arc-seconds half-power diameter reported (HPD) a year ago to 8.3 arc-seconds now. These mirror modules have been subjected to and passed all environmental tests, including vibration, acoustic, and thermal vacuum. As such this technology is ready for implementing a mission that requires a 10-arc-second mirror assembly. Further development in the next two years would make it ready for a mission requiring a 5-arc-second mirror assembly. We expect that, by the end of this decade, this technology would enable the x-ray astrophysical community to compete effectively for a major x-ray mission in the 2020s that would require one or more 1-arc-second mirror assemblies for imaging, spectroscopic, timing, and survey studies.

Astronomy from the chair - the application of the Internet in promoting of Astronomy

Science.gov (United States)

Tomic, Zoran

2014-05-01

Internet and modern communication technologies are an indispensable part of modern life. The use of the Internet makes it possible to enhance the education and expand opportunities for acquiring new knowledge. One example is Astronomy, where today thanks to the Internet, we can control telescopes that are distant from us and listen to lectures from Universities in other countries. "Astronomy from the chair" is the name for a concept where amateur astronomers can deal with astronomy from their homes using the Internet. The concept can be divided into four sections depending on the content being offered: Robotic Observatory, Virtual Observatory, Online astronomy broadcasting and Online courses. Robotic observatory is defined as an astronomical instrument and detection system that enables efficient observation without the need of a person's physical intervention. Virtual Observatory is defined as a collection of databases and software tools that use the Internet as a platform for scientific research. Online astronomy broadcasting is part of concept "Astronomy from the chair" which gives users the opportunity to get directly involved in astronomical observation organized by an amateur astronomer from somewhere in the world. Online courses are groups of sites and organizations that provide the opportunity to amateur astronomers to attend lectures, save and watch video materials from lectures, do homework, communicate with other seminar participants and in that way become familiar with the various areas of Astronomy. This paper discusses a new concept that describes how the Internet can be applied in modern education. In this paper will be described projects that allows a large number of astronomy lovers to do their own research without the need to own a large and expensive set of astronomical equipment (Virtual Telescope from Italy, Observatory "Night Hawk" from Serbia and project "Astronomy from an armchair" at Faculty of Sciences and Mathematics in Nis), to help

Teaching Astronomy with Technology

Science.gov (United States)

Austin, Carmen; Impey, Chris David; Wenger, Matthew

2015-01-01

Students today are expected to have access to computers and the Internet. Students young and old, in school and out of school, are interested in learning about astronomy, and have computers to use for this. Teach Astronomy is a website with a comprehensive digital astronomy textbook freely available to students and educators. In addition to the textbook, there are astronomy Wikipedia articles, image archives from Astronomy Picture of the Day and AstroPix, and video lectures covering all topics of astronomy. Teach Astronomy has a unique search tool called the wikimap that can be used to search through all of the resources on the site. Astronomy: State of the Art (ASOTA) is a massive, open, online course (MOOC). Over 18,000 students have enrolled over the past year and half. This MOOC has been presented in various forms. First, only to students on the web, with content released weekly on host site Udemy. Then to university students who met formally in the classroom for educational activities, but were also expected to watch lectures online on their own time. Presently, it is available online for students to go at their own pace. In the future it will be available in an extended format on a new host site, Coursera. ASOTA instructors use social media to interact with students. Students ask questions via the course host site, Udemy. Live question and answer sessions are conducted using Google Hangouts on Air, and interesting and relevant astronomy news, or supplementary educational content is shared via the ASOTA Facebook page. Teaching on the Internet may seem impersonal and impractical, but by learning to use all of these tools, instructors have the ability to interact with students, and keep them engaged.

The Formation and Disintegration of Magnetic Bright Points Observed by Sunrise/IMaX

Czech Academy of Sciences Publication Activity Database

Utz, D.; del Toro Iniesta, J.C.; Bellot Rubio, L.; Jurčák, Jan; Martinez Pillet, V.; Solanki, S.K.; Schmidt, W.

2014-01-01

Roč. 796, č. 2 (2014), 79/1-79/17 ISSN 0004-637X R&D Projects: GA MŠk(CZ) MEB061109 Institutional support: RVO:67985815 Keywords : high angular resolution * polarimeters * magnetic fields Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 5.993, year: 2014

Coordimated multi-wavelength observations of Sgr A*

Czech Academy of Sciences Publication Activity Database

Eckart, A.; Schödel, R.; Baganoff, F. K.; Morris, M.; Bertram, T.; Dovčiak, Michal; Downes, D.; Duschl, W.J.; Karas, Vladimír; König, S.; Krichbaum, T.P.; Krips, M.; Kunneriath, D.; Lu, R.-S.; Markoff, S. B.; Mauerhan, J.; Meyer, L.; Moultaka, J.; Muzic, K.; Najarro, F.; Schuster, K.; Sjouwerman, L.; Straubmeier, C.; Thum, C.; Vogel, S.; Wiesemeyer, H.; Witzel, G.; Zamaninasab, M.; Zensus, A.

2008-01-01

Roč. 131, - (2008), s. 1-15 ISSN 1742-6588. [The Universe under the Microscope – Astrophysics at High Angular Resolution. Bad Honnef, 21.04.2008-25.04.2008] Institutional research plan: CEZ:AV0Z10030501 Keywords : black holes Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics

Coordinated mm/sub-mm observations of Sagittarius A* in May 2007

Czech Academy of Sciences Publication Activity Database

Kunneriath, D.; Eckart, A.; Vogel, S.; Sjouwerman, L.; Wiesemeyer, H.; Schödel, R.; Baganoff, F. K.; Morris, M.; Bertram, T.; Dovčiak, Michal; Downes, D.; Duschl, W.J.; Karas, Vladimír; König, S.; Krichbaum, T.P.; Krips, M.; Lu, R.-S.; Markoff, S. B.; Mauerhan, J.; Meyer, L.; Moultaka, J.; Muzic, K.; Najarro, F.; Schuster, K.; Straubmeier, C.; Thum, C.; Witzel, G.; Zamaninasab, M.; Zensus, A.

2008-01-01

Roč. 131, - (2008), s. 1-7 ISSN 1742-6588. [The Universe under the Microscope – Astrophysics at High Angular Resolution. Bad Honnef, 21.04.2008-25.04.2008] Institutional research plan: CEZ:AV0Z10030501 Keywords : black holes Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics

An evolving hot spot orbiting around Sgr A*

Czech Academy of Sciences Publication Activity Database

Zamaninasab, M.; Eckart, A.; Meyer, L.; Schoedel, R.; Dovčiak, Michal; Karas, Vladimír; Kunneriath, D.; Witzel, G.; Geissübel, R.; König, S.; Straubmeier, C.; Zensus, A.

2008-01-01

Roč. 131, - (2008), s. 1-7 ISSN 1742-6588. [The Universe under the Microscope – Astrophysics at High Angular Resolution. Bad Honnef, 21.04.2008-25.04.2008] Institutional research plan: CEZ:AV0Z10030501 Keywords : black holes Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics

Outreach Testing of Ancient Astronomy

Science.gov (United States)

Sanmartin, J. R. S.; Blanco, M. B. M.

2015-10-01

This work is an outreach approach to an ubiquitous recent problem in secondary-school education: how to face back the decreasing interest in natural sciences shown by students under 'pressure' of convenient resources in digital devices/applications. The approach rests on two features. First, empowering of teen-age students to understand regular natural events around, as very few educated people they meet could do. Secondly, an understanding that rests on personal capability to test and verify experimental results from the oldest science, astronomy, with simple instruments as used from antiquity down to the Renaissance (a capability restricted to just solar and lunar motions). Because lengths in astronomy and daily life are so disparate, astronomy basically involved observing and registering values of angles (along with times), measurements being of two types, of angles on the ground and of angles in space, from the ground. First, the gnomon, a simple vertical stick introduced in Babylonia and Egypt, and then in Greece, is used to understand solar motion. The gnomon shadow turns around during any given day, varying in length and thus angle between solar ray and vertical as it turns, going through a minimum (noon time, at a meridian direction) while sweeping some angular range from sunrise to sunset. Further, the shadow minimum length varies through the year, with times when shortest and sun closest to vertical, at summer solstice, and times when longest, at winter solstice six months later. The extreme directions at sunset and sunrise correspond to the solstices, swept angular range greatest at summer, over 180 degrees, and the opposite at winter, with less daytime hours; in between, spring and fall equinoxes occur, marked by collinear shadow directions at sunrise and sunset. The gnomon allows students to determine, in addition to latitude (about 40.4° North at Madrid, say), the inclination of earth equator to plane of its orbit around the sun (ecliptic), this

A study of interference effects in Na(3S,3P)-Ne, Ar scattering experiments at high angular resolution

International Nuclear Information System (INIS)

Berg, F.T.M. van den.

1984-01-01

In this thesis the author presents measurements of differential cross sections for the scattering of Na-atoms in the ground-state and first excited-state by the rare gas atoms Ne and Ar. The scattering experiments were performed in a crossed-beam apparatus built and tested by van Deventer et al. The unique high angular-resolution (0.1 0 ) of this beam-scattering apparatus permits us (i) to remove the discrepancies that still exist between the various X 2 Σ- and A 2 PI-potential curves for Na-Ar and Na-Ne reported up to now, (ii) to obtain detailed information on the B 2 Σ-potentials for these systems and (iii) to demonstrate the necessity of taking into account the spin-uncoupling effects, in the interpretation of the experimental Na-Ne scattering patterns. (Auth.)

Astronomy and culture

CERN Document Server

Hetherington, Edith

2009-01-01

While astronomy is a burgeoning science, with tremendous increases in knowledge every year, it also has a tremendous past, one that has altered humanity's understanding of our place in the universe. The impact of astronomy on culture - whether through myths and stories, or through challenges to the intellectual status quo - is incalculable. This volume in the Greenwood Guides to the Universe series examines how human cultures, in all regions and time periods, have tried to make sense of the wonders of the universe. Astronomy and Culture shows students how people throughout time have struggled

Radio astronomy

International Nuclear Information System (INIS)

Parijskij, Y.N.; Gossachinskij, I.V.; Zuckerman, B.; Khersonsky, V.K.; Pustilnik, S.; Robinson, B.J.

1976-01-01

A critical review of major developments and discoveries in the field of radioastronomy during the period 1973-1975 is presented. The report is presented under the following headings:(1) Continuum radiation from the Galaxy; (2) Neutral hydrogen, 21 cm (galactic and extragalactic) and recombination lines; (3) Radioastronomy investigations of interstellar molecules; (4) Extragalactic radio astronomy and (6) Development in radio astronomy instruments. (B.R.H.)

Galactic radio astronomy

CERN Document Server

Sofue, Yoshiaki

2017-01-01

This book is a concise primer on galactic radio astronomy for undergraduate and graduate students, and provides wide coverage of galactic astronomy and astrophysics such as the physics of interstellar matter and the dynamics and structure of the Milky Way Galaxy and galaxies. Radio astronomy and its technological development have led to significant progress in galactic astronomy and contributed to understanding interstellar matter and galactic structures. The book begins with the fundamental physics of radio-wave radiation, i.e., black body radiation, thermal emission, synchrotron radiation, and HI and molecular line emissions. The author then gives overviews of ingredients of galactic physics, including interstellar matter such as the neutral (HI), molecular hydrogen, and ionized gases, as well as magnetic fields in galaxies. In addition, more advanced topics relevant to the Galaxy and galaxies are also contained here: star formation, supernova remnants, the Galactic Center and black holes, galactic dynamics...

Mass loss of evolved massive stars: the circumstellar environment at high angular resolution

International Nuclear Information System (INIS)

Montarges, Miguel

2014-01-01

Mass loss of evolved stars is still largely mysterious, despite its importance as the main evolution engine for the chemical composition of the interstellar medium. For red supergiants (RSG), the triggering of the outflow and the mechanism of dust condensation remain unknown. Concerning red giant stars, we still do not know how their mass loss is able to form a bipolar planetary nebula. During my PhD thesis, I observed evolved stars with high angular resolution techniques. They allowed us to study the surface and the close environment of these stars, from where mass loss originates. With near-infrared interferometric observations, I characterized the water vapor and carbon monoxide envelope of the nearby RSG Betelgeuse. I also monitored a hot spot on its surface and analyzed the structure of its convection, as well as that of Antares (another very nearby supergiant) thanks to radiative hydrodynamical simulations. Diffraction-limited imaging techniques (near-infrared adaptive optics, ultraviolet space telescope) allowed me to observe the evolution of inhomogeneities in the circumstellar envelope of Betelgeuse and to discover a circumstellar disk around L2 Puppis, an asymptotic giant branch star. These multi-scale and multi-wavelength observations obtained at several epochs allowed us to monitor the evolution of the structures and to derive information on the dynamics of the stellar environment. With a wider stellar sample expected in the next few years, this observing program will allow a better understanding of the mass loss of evolved stars. (author)

Dense sampled transmission matrix for high resolution angular spectrum imaging through turbid media via compressed sensing (Conference Presentation)

Science.gov (United States)

Jang, Hwanchol; Yoon, Changhyeong; Choi, Wonshik; Eom, Tae Joong; Lee, Heung-No

2016-03-01

We provide an approach to improve the quality of image reconstruction in wide-field imaging through turbid media (WITM). In WITM, a calibration stage which measures the transmission matrix (TM), the set of responses of turbid medium to a set of plane waves with different incident angles, is preceded to the image recovery. Then, the TM is used for estimation of object image in image recovery stage. In this work, we aim to estimate highly resolved angular spectrum and use it for high quality image reconstruction. To this end, we propose to perform a dense sampling for TM measurement in calibration stage with finer incident angle spacing. In conventional approaches, incident angle spacing is made to be large enough so that the columns in TM are out of memory effect of turbid media. Otherwise, the columns in TM are correlated and the inversion becomes difficult. We employ compressed sensing (CS) for a successful high resolution angular spectrum recovery with dense sampled TM. CS is a relatively new information acquisition and reconstruction framework and has shown to provide superb performance in ill-conditioned inverse problems. We observe that the image quality metrics such as contrast-to-noise ratio and mean squared error are improved and the perceptual image quality is improved with reduced speckle noise in the reconstructed image. This results shows that the WITM performance can be improved only by executing dense sampling in the calibration stage and with an efficient signal reconstruction framework without elaborating the overall optical imaging systems.

Women in Astronomy Workshop Report

OpenAIRE

Brough, Sarah; Bauer, Amanda E.; Brooks, Kate; Hopkins, Andrew; Maddison, Sarah

2011-01-01

Here we report on the Women in Astronomy Workshop (http://asawomeninastronomy.org/meetings/wia2011/), which was held on 13 May 2011 in Sydney, Australia. The workshop was organised by the Astronomical Society of Australia's Chapter on Women in Astronomy, to discuss some of the issues that face women in astronomy and make recommendations to help support the success of women in Australian astronomy but came to broader conclusions that have value for the whole astronomical community. The worksho...

The purpose of astronomy

OpenAIRE

Davoust, Emmanuel

1995-01-01

This is a presentation of the purpose of astronomy in the context of modern society. After exposing two misconceptions about astronomy, I detail its role in five domains, certified knowledge, incorporated abilities, innovations, collective goods, and popular science; with each domain is associated an institution, an incentive, and a method of evaluation. Finally, I point out the role of astronomy as a source of inspiration in other fields than science.

Characteristic evolutions in numerical relativity using six angular patches

International Nuclear Information System (INIS)

Reisswig, Christian; Bishop, Nigel T; Lai, Chi Wai; Thornburg, Jonathan; Szilagyi, Bela

2007-01-01

The characteristic approach to numerical relativity is a useful tool in evolving gravitational systems. In the past this has been implemented using two patches of stereographic angular coordinates. In other applications, a six-patch angular coordinate system has proved effective. Here we investigate the use of a six-patch system in characteristic numerical relativity, by comparing an existing two-patch implementation (using second-order finite differencing throughout) with a new six-patch implementation (using either second- or fourth-order finite differencing for the angular derivatives). We compare these different codes by monitoring the Einstein constraint equations, numerically evaluated independently from the evolution. We find that, compared to the (second-order) two-patch code at equivalent resolutions, the errors of the second-order six-patch code are smaller by a factor of about 2, and the errors of the fourth-order six-patch code are smaller by a factor of nearly 50

Characteristic evolutions in numerical relativity using six angular patches

Energy Technology Data Exchange (ETDEWEB)

Reisswig, Christian [Max-Planck-Institut fuer Gravitationsphysik, Albert-Einstein-Institut, Am Muehlenberg 1, D-14476 Golm (Germany); Bishop, Nigel T [Department of Mathematical Sciences, University of South Africa, PO Box 392, Unisa 0003, South Africa (South Africa); Lai, Chi Wai [Department of Mathematical Sciences, University of South Africa, PO Box 392, Unisa 0003, South Africa (South Africa); Thornburg, Jonathan [Max-Planck-Institut fuer Gravitationsphysik, Albert-Einstein-Institut, Am Muehlenberg 1, D-14476 Golm (Germany); Szilagyi, Bela [Max-Planck-Institut fuer Gravitationsphysik, Albert-Einstein-Institut, Am Muehlenberg 1, D-14476 Golm (Germany)

2007-06-21

The characteristic approach to numerical relativity is a useful tool in evolving gravitational systems. In the past this has been implemented using two patches of stereographic angular coordinates. In other applications, a six-patch angular coordinate system has proved effective. Here we investigate the use of a six-patch system in characteristic numerical relativity, by comparing an existing two-patch implementation (using second-order finite differencing throughout) with a new six-patch implementation (using either second- or fourth-order finite differencing for the angular derivatives). We compare these different codes by monitoring the Einstein constraint equations, numerically evaluated independently from the evolution. We find that, compared to the (second-order) two-patch code at equivalent resolutions, the errors of the second-order six-patch code are smaller by a factor of about 2, and the errors of the fourth-order six-patch code are smaller by a factor of nearly 50.

Stamping through astronomy

CERN Document Server

Dicati, Renato

2013-01-01

Stamps and other postal documents are an attractive vehicle for presenting astronomy and its development. Written with expertise and great enthusiasm, this unique book offers a historical and philatelic survey of astronomy and some related topics on space exploration. It contains more than 1300 color reproductions of stamps relating to the history of astronomy, ranging from the earliest observations of the sky to modern research conducted with satellites and space probes. Featured are the astronomers and astrophysicists who contributed to this marvelous story – not only Ptolemy, Copernicus, Kepler, Newton, Herschel, and Einstein but also hundreds of other minor protagonists who played an important role in the development of this, the most ancient yet the most modern of all the sciences. The book also examines in depth the diverse areas which have contributed to the history of astronomy, including the instrumentation, the theories, and the observations. Many stamps illustrate the beauty and the mystery of ce...

Improving Astronomy Achievement and Attitude through Astronomy Summer Project: A Design, Implementation and Assessment

Science.gov (United States)

Türk, Cumhur; Kalkan, Hüseyin; Iskeleli', Nazan Ocak; Kiroglu, Kasim

2016-01-01

The purpose of this study is to examine the effects of an astronomy summer project implemented in different learning activities on elementary school students, pre-service elementary teachers and in-service teachers' astronomy achievement and their attitudes to astronomy field. This study is the result of a five-day, three-stage, science school,…

H.E.S.S. observations of RX J1713.7-3946 with improved angular and spectral resolution: Evidence for gamma-ray emission extending beyond the X-ray emitting shell

Science.gov (United States)

H. E. S. S. Collaboration; Abdalla, H.; Abramowski, A.; Aharonian, F.; Benkhali, F. Ait; Akhperjanian, A. G.; Andersson, T.; Angüner, E. O.; Arrieta, M.; Aubert, P.; Backes, M.; Balzer, A.; Barnard, M.; Becherini, Y.; Tjus, J. Becker; Berge, D.; Bernhard, S.; Bernlöhr, K.; Blackwell, R.; Böttcher, M.; Boisson, C.; Bolmont, J.; Bordas, P.; Bregeon, J.; Brun, F.; Brun, P.; Bryan, M.; Bulik, T.; Capasso, M.; Carr, J.; Casanova, S.; Cerruti, M.; Chakraborty, N.; Chalme-Calvet, R.; Chaves, R. C. G.; Chen, A.; Chevalier, J.; Chrétien, M.; Colafrancesco, S.; Cologna, G.; Condon, B.; Conrad, J.; Cui, Y.; Davids, I. D.; Decock, J.; Degrange, B.; Deil, C.; Devin, J.; deWilt, P.; Dirson, L.; Djannati-Ataï, A.; Domainko, W.; Donath, A.; Drury, L. O.'C.; Dubus, G.; Dutson, K.; Dyks, J.; Edwards, T.; Egberts, K.; Eger, P.; Ernenwein, J.-P.; Eschbach, S.; Farnier, C.; Fegan, S.; Fernandes, M. V.; Fiasson, A.; Fontaine, G.; Förster, A.; Fukuyama, T.; Funk, S.; Füßling, M.; Gabici, S.; Gajdus, M.; Gallant, Y. A.; Garrigoux, T.; Giavitto, G.; Giebels, B.; Glicenstein, J. F.; Gottschall, D.; Goyal, A.; Grondin, M.-H.; Hadasch, D.; Hahn, J.; Haupt, M.; Hawkes, J.; Heinzelmann, G.; Henri, G.; Hermann, G.; Hervet, O.; Hinton, J. A.; Hofmann, W.; Hoischen, C.; Holler, M.; Horns, D.; Ivascenko, A.; Jacholkowska, A.; Jamrozy, M.; Janiak, M.; Jankowsky, D.; Jankowsky, F.; Jingo, M.; Jogler, T.; Jouvin, L.; Jung-Richardt, I.; Kastendieck, M. A.; Katarzyński, K.; Katz, U.; Kerszberg, D.; Khélifi, B.; Kieffer, M.; King, J.; Klepser, S.; Klochkov, D.; Kluźniak, W.; Kolitzus, D.; Komin, Nu.; Kosack, K.; Krakau, S.; Kraus, M.; Krayzel, F.; Krüger, P. P.; Laffon, H.; Lamanna, G.; Lau, J.; Lees, J.-P.; Lefaucheur, J.; Lefranc, V.; Lemière, A.; Lemoine-Goumard, M.; Lenain, J.-P.; Leser, E.; Lohse, T.; Lorentz, M.; Liu, R.; López-Coto, R.; Lypova, I.; Marandon, V.; Marcowith, A.; Mariaud, C.; Marx, R.; Maurin, G.; Maxted, N.; Mayer, M.; Meintjes, P. J.; Meyer, M.; Mitchell, A. M. W.; Moderski, R.; Mohamed, M.; Mohrmann, L.; Morå, K.; Moulin, E.; Murach, T.; Naurois, M. de; Niederwanger, F.; Niemiec, J.; Oakes, L.; O'Brien, P.; Odaka, H.; Öttl, S.; Ohm, S.; Ostrowski, M.; Oya, I.; Padovani, M.; Panter, M.; Parsons, R. D.; Pekeur, N. W.; Pelletier, G.; Perennes, C.; Petrucci, P.-O.; Peyaud, B.; Piel, Q.; Pita, S.; Poon, H.; Prokhorov, D.; Prokoph, H.; Pühlhofer, G.; Punch, M.; Quirrenbach, A.; Raab, S.; Reimer, A.; Reimer, O.; Renaud, M.; los Reyes, R. de; Rieger, F.; Romoli, C.; Rosier-Lees, S.; Rowell, G.; Rudak, B.; Rulten, C. B.; Sahakian, V.; Salek, D.; Sanchez, D. A.; Santangelo, A.; Sasaki, M.; Schlickeiser, R.; Schüssler, F.; Schulz, A.; Schwanke, U.; Schwemmer, S.; Settimo, M.; Seyffert, A. S.; Shafi, N.; Shilon, I.; Simoni, R.; Sol, H.; Spanier, F.; Spengler, G.; Spies, F.; Stawarz, Ł.; Steenkamp, R.; Stegmann, C.; Stinzing, F.; Stycz, K.; Sushch, I.; Takahashi, T.; Tavernet, J.-P.; Tavernier, T.; Taylor, A. M.; Terrier, R.; Tibaldo, L.; Tiziani, D.; Tluczykont, M.; Trichard, C.; Tuffs, R.; Uchiyama, Y.; van der Walt, D. J.; Eldik, C. van; Rensburg, C. van; Soelen, B. van; Vasileiadis, G.; Veh, J.; Venter, C.; Viana, A.; Vincent, P.; Vink, J.; Voisin, F.; Völk, H. J.; Volpe, F.; Vuillaume, T.; Wadiasingh, Z.; Wagner, S. J.; Wagner, P.; Wagner, R. M.; White, R.; Wierzcholska, A.; Willmann, P.; Wörnlein, A.; Wouters, D.; Yang, R.; Zabalza, V.; Zaborov, D.; Zacharias, M.; Zdziarski, A. A.; Zech, A.; Zefi, F.; Ziegler, A.; Żywucka, N.

2018-04-01

Supernova remnants exhibit shock fronts (shells) that can accelerate charged particles up to very high energies. In the past decade, measurements of a handful of shell-type supernova remnants in very high-energy gamma rays have provided unique insights into the acceleration process. Among those objects, RX J1713.7-3946 (also known as G347.3-0.5) has the largest surface brightness, allowing us in the past to perform the most comprehensive study of morphology and spatially resolved spectra of any such very high-energy gamma-ray source. Here we present extensive new H.E.S.S. measurements of RX J1713.7-3946, almost doubling the observation time compared to our previous publication. Combined with new improved analysis tools, the previous sensitivity is more than doubled. The H.E.S.S. angular resolution of 0.048° (0.036° above 2 TeV) is unprecedented in gamma-ray astronomy and probes physical scales of 0.8 (0.6) parsec at the remnant's location. The new H.E.S.S. image of RX J1713.7-3946 allows us to reveal clear morphological differences between X-rays and gamma rays. In particular, for the outer edge of the brightest shell region, we find the first ever indication for particles in the process of leaving the acceleration shock region. By studying the broadband energy spectrum, we furthermore extract properties of the parent particle populations, providing new input to the discussion of the leptonic or hadronic nature of the gamma-ray emission mechanism. All images (FITS files) are 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/612/A6

Astronomy in Iraq

Science.gov (United States)

Alsabti, A. W.

2006-08-01

The history of modern Iraqi astronomy is reviewed. During the early 1970's Iraqi astronomy witnessed significant growth through the introduction of the subject at university level and extensively within the school curriculum. In addition, astronomy was popularised in the media, a large planetarium was built in Baghdad, plus a smaller one in Basra. Late 1970 witnessed the construction of the Iraqi National Observatory at Mount Korek in Iraqi Kurdistan. The core facilities of the Observatory included 3.5-meter and 1.25-meter optical telescopes, and a 30-meter radio telescope for millimetre wavelength astronomy. The Iraqi Astronomical Society was founded and Iraq joined the IAU in 1976. During the regime of Saddam Hussain in the 1980's, the Observatory was attacked by Iranian artillery during the Iraq-Iran war, and then again during the second Gulf war by the US air force. Years of sanctions during the 1990's left Iraq cut off from the rest of the international scientific community. Subscriptions to astronomical journals were halted and travel to conferences abroad was virtually non-existent. Most senior astronomers left the country for one reason or another. Support from expatriate Iraqi astronomers existed (and still exists) however, this is not sufficient. Recent changes in Iraq, and the fall of Saddam's regime, has meant that scientific communication with the outside world has resumed to a limited degree. The Ministry of Higher Education in Baghdad, Baghdad University and the Iraqi National Academy of Science, have all played active roles in re-establishing Iraqi astronomy and re-building the damaged Observatory at Mount Korek. More importantly the University of Sallahudin in Erbil, capital of Iraqi Kurdistan, has taken particular interest in astronomy and the Observatory. Organized visits to the universities, and also to the Observatory, have given us a first-hand assessment of the scale of the damage to the Observatory, as well as the needs of astronomy teaching

The Cambridge encyclopaedia of astronomy

CERN Document Server

1977-01-01

Astronomy has been transformed in the last two decades by a series of dramatic discoveries that have left most reference books completely out of date. The Cambridge Encyclopaedia of Astronomy presents a broadly based survey of the whole of astronomy which places emphasis on these critical new findings.

Astronomy in Everyday Life

Science.gov (United States)

Rosenberg, M.; Bladon, G.; Russo, P.; Christensen, L. L.

2014-01-01

For a long time astronomers and other scientists believed that the importance of their work was evident to society. But in these difficult days of financial austerity, even the most obvious benefits of science have to undergo careful scrutiny. So, now more than ever is the time to highlight the importance of astronomy as a field in terms of its contributions to our technology, our mind sets and our lives. Here we will outline both the tangible and intangible reasons why astronomy is an important part of society. Whilst considerable attention will be given to technology and knowledge transfer from astronomy, perhaps the most important contribution outlined is the awareness that astronomy gives us of the vastness of the Universe and our place within it.

How Create an Astronomy Outreach Program to Bring Astronomy to Thousands of People at Outdoor Concerts Astronomy Festivals, or Tourist Sites

Science.gov (United States)

Lubowich, Donald

2015-08-01

I describe how to create an astronomy program for thousands of people at outdoor concerts based on my $308,000 NASA-funded Music and Astronomy Under the Stars (MAUS) program (60 events 2009 - 2013), and the Astronomy Festival on the National Mall (AFNM, 10,000 people/yr).MAUS reached 50,000 music lovers at local parks and at the Central Park Jazz, Newport Folk, Ravinia, or Tanglewood Music Festivals with classical, folk, pop/rock, opera, Caribbean, or county-western concerts assisted by astronomy clubs. Yo-Yo-Ma, the Chicago and Boston Symphony Orchestras, Ravi Coltrane, Esperanza Spalding, Phish, Blood Sweat and Tears, Deep Purple, Tony Orlando, and Wilco performed at these events. AFNM was started in 2010 with co-sponsorship by the White House Office of Science and Technology Policy. MAUS and AFMN combine solar, optical, and radio telescope observations; large posters/banners; hands-on activities, imaging with a cell phone mount; citizen science activities; hand-outs; and teacher info packet. Representatives from scientific institutions participated. Tyco Brahe, Johannes Kepler, and Caroline Herschel made guest appearances.MAUS reached underserved groups and attracted large crowds. Young kids participated in this family learning experience-often the first time they looked through a telescope. While < 50% of the participants took part in a science activity in the past year, they found MAUS enjoyable and understandable; learned about astronomy; wanted to learn more; and increased their interest in science (ave. rating 3.6/4). MAUS is effective in promoting science education!Lessons learned: plan early; create partnerships with parks, concert organizers, and astronomy clubs; test equipment; have backup equipment; create professional displays; select the best location to obtain a largest number of participants; use social media/www sites to promote the events; use many telescopes for multiple targets; project a live image or video; select equipment that is easy to

Quickly Creating Interactive Astronomy Illustrations

Science.gov (United States)

Slater, Timothy F.

2015-01-01

An innate advantage for astronomy teachers is having numerous breathtaking images of the cosmos available to capture students' curiosity, imagination, and wonder. Internet-based astronomy image libraries are numerous and easy to navigate. The Astronomy Picture of the Day, the Hubble Space Telescope image archive, and the NASA Planetary…

Music Inspired by Astronomy: A Selected Listing for the International Year of Astronomy

Science.gov (United States)

Fraknoi, A.

2008-11-01

Part of the aim of the International Year of Astronomy is to show the connections between astronomy and other areas of human culture. Such connections are easily found in music, where astronomical ideas have found a wide range of expression. This is not a comprehensive listing, but a sampling of some of the pieces that are available on CD's, and that may be of particular interest to educators and astronomy enthusiasts. To qualify for the list, a piece (or the composer's vision for it) has to include some real science and not just an astronomical term in the title or in a few lyrics. For example, we do not list The Planets, by Gustav Holst, since it treats the astrological view of the planets. And we regret that Philip Glass' opera Galileo is not available on CD and therefore cannot be listed. Nor do we include the thousands of popular songs that use the moon or the stars for an easy rhyme or a quick romantic image. And, while many jazz pieces have astronomy in the title, it is often hard to know just how the piece and the astronomy go together; so we've sadly omitted jazz too. For those with old-fashioned ears, like the author, we note that no warranty is made that all these pieces are easy to listen to, but each takes some key idea from astronomy and makes music out of it. A more comprehensive discussion can be found in my article in Astronomy Education Review: http://aer.noao.edu/cgi-bin/article.pl?id=193

Polarization-Dependent Measurements of Molecular Super Rotors with Oriented Angular Momenta

Science.gov (United States)

Murray, Matthew J.; Toro, Carlos; Liu, Qingnan; Mullin, Amy S.

2014-05-01

Controlling molecular motion would enable manipulation of energy flow between molecules. Here we have used an optical centrifuge to investigate energy transfer between molecular super rotors with oriented angular momenta. The polarizable electron cloud of the molecules interacts with the electric field of linearly polarized light that angularly accelerates over the time of the optical pulse. This process drives molecules into high angular momentum states that are oriented with the optical field and have energies far from equilibrium. High resolution transient IR spectroscopy reveals the dynamics of collisional energy transfer for these super excited rotors. The results of this study leads to a more fundamental understanding of energy balance in non-equilibrium environments and the physical and chemical properties of gases in a new regime of energy states. Results will be presented for several super rotor species including carbon monoxide, carbon dioxide, and acetylene. Polarization-dependent measurements reveal the extent to which the super rotors maintain spatial orientation of high angular momentum states.

Astronomy Explained

Science.gov (United States)

North, Gerald

Every year large numbers of people take up the study of astronomy, mostly at amateur level. There are plenty of elementary books on the market, full of colourful photographs, but lacking in proper explanations of how and why things are as they are. Many people eventually wish to go beyond the 'coffee-table book' stage and study this fascinating subject in greater depth. This book is written for them. In addition, many people sit for public examinations in this subject each year and this book is also intended to be of use to them. All the topics from the GCSE syllabus are covered here, with sample questions at the end of each chapter. Astronomy Explained provides a comprehensive treatment of the subject in more depth than is usually found in elementary works, and will be of interest to both amateur astronomers and students of astronomy.

Teaching Astronomy in UK Schools

Science.gov (United States)

Roche, Paul; Roberts, Sarah; Newsam, Andy; Barclay, Charles

2012-01-01

This article attempts to summarise the good, bad and (occasionally) ugly aspects of teaching astronomy in UK schools. It covers the most common problems reported by teachers when asked about covering the astronomy/space topics in school. Particular focus is given to the GCSE Astronomy qualification offered by Edexcel (which is currently the…

A Grand Vision for European Astronomy

Science.gov (United States)

2007-09-01

Today, and for the first time, astronomers share their global Science Vision for European Astronomy in the next two decades. This two-year long effort by the ASTRONET network of funding agencies, sponsored by the European Commission and coordinated by INSU-CNRS, underscores Europe's ascension to world leadership in astronomy and its will to maintain that position. It will be followed in just over a year by a prioritised roadmap for the observational facilities needed to implement the Vision. Implementation of these plans will ensure that Europe fully contributes to Mankind's ever deeper understanding of the wonders of our Universe. astronet logo "This is a great opportunity to help create a vibrant long-term future for astronomy and science" says Tim de Zeeuw (Leiden Observatory, The Netherlands) who led this community-wide effort. The ASTRONET Science Vision provides a comprehensive overview of the most important scientific questions that European astronomy should address in the next twenty years. The four key questions are the extremes of the Universe, from the nature of the dark matter and dark energy that comprise over 95% of the Universe to the physics of extreme objects such as black holes, neutron stars, and gamma-ray bursts; the formation of galaxies from the first seeds to our Milky Way; the formation of stars and planets and the origin of life; and the crucial question of how do we (and our Solar System) fit in the global picture. These themes reach well beyond the realm of traditional astronomy into the frontiers of physics and biology. The Vision identifies the major new facilities that will be needed to achieve these goals, but also stresses the need for parallel developments in theory and numerical simulations, high-performance computing resources, efficient astronomical data archiving and the European Virtual Observatory, as well as in laboratory astrophysics. "This report is a key input for the even more challenging task of developing a prioritised

Extragalactic infrared astronomy

International Nuclear Information System (INIS)

Gondhalekar, P.M.

1985-05-01

The paper concerns the field of Extragalactic Infrared Astronomy, discussed at the Fourth RAL Workshop on Astronomy and Astrophysics. Fifteen papers were presented on infrared emission from extragalactic objects. Both ground-(and aircraft-) based and IRAS infrared data were reviewed. The topics covered star formation in galaxies, active galactic nuclei and cosmology. (U.K.)

Development of insula connectivity between ages 12 and 30 revealed by high angular resolution diffusion imaging.

Science.gov (United States)

Dennis, Emily L; Jahanshad, Neda; McMahon, Katie L; de Zubicaray, Greig I; Martin, Nicholas G; Hickie, Ian B; Toga, Arthur W; Wright, Margaret J; Thompson, Paul M

2014-04-01

The insula, hidden deep within the Sylvian fissures, has proven difficult to study from a connectivity perspective. Most of our current information on the anatomical connectivity of the insula comes from studies of nonhuman primates and post mortem human dissections. To date, only two neuroimaging studies have successfully examined the connectivity of the insula. Here we examine how the connectivity of the insula develops between ages 12 and 30, in 307 young adolescent and adult subjects scanned with 4-Tesla high angular resolution diffusion imaging (HARDI). The density of fiber connections between the insula and the frontal and parietal cortex decreased with age, but the connection density between the insula and the temporal cortex generally increased with age. This trajectory is in line with well-known patterns of cortical development in these regions. In addition, males and females showed different developmental trajectories for the connection between the left insula and the left precentral gyrus. The insula plays many different roles, some of them affected in neuropsychiatric disorders; this information on the insula's connectivity may help efforts to elucidate mechanisms of brain disorders in which it is implicated. Copyright © 2013 Wiley Periodicals, Inc.

Astronomy all the time for everybody

Science.gov (United States)

Grigore, Valentin

2015-08-01

General contextCommunicating astronomy with the public must be done all year and with all community members using all the available methods to promote the all aspects of astronomy: education, science, research, new technologies, dark-sky protection, astrophotography, mythology, astropoetry, astro arts and music.An annual calendarTwo aspect must be taken in consideration when create a calendar of activity:- astronomical events (eclipses, meteor showers, comets, etc.)- international and local astronomical events: Global Astronomy Months, Astronomy Day, Globe at Night, ISAN, public activitiesCommunicating astronomy with the whole communityA description of the experience of the author organizing over 500 events in 30 years of activity including all the community members: general public, students, teachers, artists, authorities, people with disabilities, minor and adult prisoners, etc.An experience of seven years as TV producer of the astronomy TV show “Ùs and the Sky” is presented.Promotion of the activityThe relation with the mass-media is an important aspect communicating astronomy with the public.Mass-media between rating and correct information of the public.The role of the cooperation with the community in astronomy projectsA successful model: EURONEAR project

Astronomy, Astrology, and Medicine

Science.gov (United States)

Greenbaum, Dorian Gieseler

Astronomy and astrology were combined with medicine for thousands of years. Beginning in Mesopotamia in the second millennium BCE and continuing into the eighteenth century, medical practitioners used astronomy/astrology as an important part of diagnosis and prescription. Throughout this time frame, scientists cited the similarities between medicine and astrology, in addition to combining the two in practice. Hippocrates and Galen based medical theories on the relationship between heavenly bodies and human bodies. In an enduring cultural phenomenon, parts of the body as well as diseases were linked to zodiac signs and planets. In Renaissance universities, astronomy and astrology were studied by students of medicine. History records a long tradition of astrologer-physicians. This chapter covers the topic of astronomy, astrology, and medicine from the Old Babylonian period to the Enlightenment.

Armenian Archaeoastronomy and Astronomy in Culture

Science.gov (United States)

Mickaelian, Areg M.; Farmanyan, Sona V.

2016-12-01

A review is given on archaeoastronomy in Armenia and astronomical knowledge reflected in the Armenian culture. Astronomy in Armenia was popular since ancient times and Armenia is rich in its astronomical heritage, such as the names of the constellations, ancient observatories, Armenian rock art (numerous petroglyphs of astronomical content), ancient and medieval Armenian calendars, astronomical terms and names used in Armenian language since II-I millennia B.C., records of astronomical events by ancient Armenians (e.g. Halley's comet in 87 B.C., supernovae explosion in 1054), the astronomical heritage of the Armenian medieval great thinker Anania Shirakatsi's (612-685), medieval sky maps and astronomical devices by Ghukas (Luca) Vanandetsi (XVII-XVIII centuries) and Mkhitar Sebastatsi (1676-1749), etc. For systemization and further regular studies, we have created a webpage devoted to Armenian archaeoastronomical matters at Armenian Astronomical Society (ArAS) website. Issues on astronomy in culture include astronomy in ancient Armenian cultures, ethnoastronomy, astronomy in Armenian religion and mythology, astronomy and astrology, astronomy in folklore and poetry, astronomy in arts, astrolinguistics and astroheraldry. A similar webpage for Astronomy in Armenian Culture is being created at ArAS website and a permanent section "Archaeoastronomy and Astronomy in Culture" has been created in ArAS Electronic Newsletter. Several meetings on this topic have been organized in Armenia during 2007-2014, including the archaeoastronomical meetings in 2012 and 2014, and a number of books have been published. Several institutions are related to these studies coordinated by Byurakan Astrophysical Observatory (BAO) and researchers from the fields of astronomy, history, archaeology, literature, linguistics, etc. are involved.

Professional AngularJS

CERN Document Server

Karpov, Valeri

2015-01-01

A comprehensive guide to AngularJS, Google's open-source client-side framework for app development. Most of the existing guides to AngularJS struggle to provide simple and understandable explanations for more advanced concepts. As a result, some developers who understand all the basic concepts of AngularJS struggle when it comes to building more complex real-world applications. Professional AngularJS provides a thorough understanding of AngularJS, covering everything from basic concepts, such as directives and data binding, to more advanced concepts like transclusion, build systems, and auto

Astronomy, Indigenous Knowledge and Interpretation: Advancing studies of Cultural Astronomy in South Africa

OpenAIRE

Holbrook, Jarita

2016-01-01

The International Society for Archaeoastronomy and Astronomy in Culture (ISAAC) Oxford X conference came to Africa for the first time in 2014. Oxford X exposed South African students and researchers to cultural astronomy data collection and analysis methods, as well as to potential mentors to further the goal of advancing the field. Cultural Astronomy studies in South Africa, however, remain in a nascent stage, which in some ways can be said for the entire field, but especially when it comes ...

Fundamental astronomy

CERN Document Server

Kröger, Pekka; Oja, Heikki; Poutanen, Markku; Donner, Karl

2017-01-01

Now in its sixth edition this successful undergraduate textbook gives a well-balanced and comprehensive introduction to the topics of classical and modern astronomy. While emphasizing both the astronomical concepts and the underlying physical principles, the text provides a sound basis for more profound studies in the astronomical sciences. The chapters on galactic and extragalactic astronomy as well as cosmology were extensively modernized in the previous edition. In this new edition they have been further revised to include more recent results. The long chapter on the solar system has been split into two parts: the first one deals with the general properties, and the other one describes individual objects. A new chapter on exoplanets has been added to the end of the book next to the chapter on astrobiology. In response to the fact that astronomy has evolved enormously over the last few years, only a few chapters of this book have been left unmodified. Long considered a standard text for physical science maj...

Review of decametric radio astronomy - instruments and science

International Nuclear Information System (INIS)

Erickson, W.C.; Cane, H.V.

1987-01-01

The techniques and instruments used in Galactic and extragalactic radio astronomy at dkm wavelengths are surveyed, and typical results are summarized. Consideration is given to the large specialized phased arrays used for early surveys, the use of wideband elements to increase frequency agility, experimental VLBI observations, and limitations on ground-based observations below about 10 MHz (where the proposed LF Space Array, with resolution 0.5-5 arcmin, could make a major contribution). Observations discussed cover the Galactic center, the Galactic background radiation, SNRs, compact Galactic sources, the ISM, and large extragalactic sources. 38 references

Ultra-high resolution coded wavefront sensor

KAUST Repository

Wang, Congli

2017-06-08

Wavefront sensors and more general phase retrieval methods have recently attracted a lot of attention in a host of application domains, ranging from astronomy to scientific imaging and microscopy. In this paper, we introduce a new class of sensor, the Coded Wavefront Sensor, which provides high spatio-temporal resolution using a simple masked sensor under white light illumination. Specifically, we demonstrate megapixel spatial resolution and phase accuracy better than 0.1 wavelengths at reconstruction rates of 50 Hz or more, thus opening up many new applications from high-resolution adaptive optics to real-time phase retrieval in microscopy.

Bad Astronomy Goes Hollywood

Science.gov (United States)

Plait, P.

2003-05-01

It can be argued that astronomy is the oldest of all the sciences, so you'd think that after all this time people would have a pretty good understanding of it. In reality, however, misconceptions about astronomy abound, and even basic concepts are misunderstood. There are many sources of these cosmic misconceptions, including incorrect textbooks, parents and/or teachers who don't understand astronomy and therefore spread misinformation, urban legends, and so on. Perhaps the most pervasive source of bad astronomy is Hollywood. Science fiction movies are enormously popular, but are commonly written and directed by people who don't have even a passing familiarity with astronomy. The smash hit "Armageddon" (the number one box office movie of 1998), for example, used vast quantities of incorrect astronomy in the plot. It reinforced such popular misconceptions as huge asteroids impacting the Earth with little warning, small meteorites being hot when they impact, air existing in space, and that a simple bomb can blow up an asteroid the size of a small moon (even when the bomb is buried only 800 feet deep!). However, movie scenes can be used as a hook that engages the student, helping them learn and remember the correct science. In this talk, I will light-heartedly discuss specific examples of common misinformation, using movie clips, diagrams, and a splash of common sense to show just where Hollywood gets it wrong, and what you can do to help students and the public get it right.

The physics-astronomy frontier

International Nuclear Information System (INIS)

Hoyle, F.; Narlikar, K.

1980-01-01

Spacetime diagrams and the structure of matter are considered, and aspects of electrical interaction are investigated. Attention is given to radiation, quantum mechanics, spectrum lines, black bodies, stellar spectra, the H-R diagram, radio astronomy, millimeter-wave astronomy, interstellar grains and infrared astronomy, and X-ray astronomy. The strong and weak interactions are examined, taking into account atoms, nuclei, the evolution of stars, and the measurement of astronomical distances. A description of gravitational interaction is also presented. The laws of motion and gravitation are considered along with black holes, the significance of cosmology, Hubble's law, the expanding universe, the symmetries of the universe, Olbers' paradox, the big-bang universe, Mach's principle, the meaning of the expansion of the system of galaxies, the redshift-magnitude relation of Hubble and Humason, the early universe, and the geometry of special relativity

The Relationship between Preservice Science Teachers' Attitude toward Astronomy and Their Understanding of Basic Astronomy Concepts

Science.gov (United States)

Bektasli, Behzat

2016-01-01

Turkish preservice science teachers have been taking a two-credit astronomy class during the last semester of their undergraduate program since 2010. The current study aims to investigate the relationship between preservice science teachers' astronomy misconceptions and their attitudes toward astronomy. Preservice science teachers were given an…

White supremacism and Islamic astronomy in history of astronomy texts from the eighteenth century to the present day

Science.gov (United States)

Lockard, Joe

2018-04-01

This paper reviews manifestations of racism in European and American histories of Arab and Persian astronomy from the eighteenth century to the present day. Its first section discusses representation of Islamic astronomy from Adam Smith to late Victorian writers, particularly tracing ideas of Arab unoriginality and scientific incapacity. The second section first relates the appearance of scientific racism in the early twentieth-century historiography of astronomy, then how the rise of scientifically and linguistically competent scholarship in the latter twentieth century provided much-improved information on Islamic achievements in astronomy. The paper’s conclusion underlines the importance of avoiding ethnic supremacism and integrating research on Islamic astronomy into teaching and publishing on the history of astronomy.

Uncertainty principle for angular position and angular momentum

International Nuclear Information System (INIS)

Franke-Arnold, Sonja; Barnett, Stephen M; Yao, Eric; Leach, Jonathan; Courtial, Johannes; Padgett, Miles

2004-01-01

The uncertainty principle places fundamental limits on the accuracy with which we are able to measure the values of different physical quantities (Heisenberg 1949 The Physical Principles of the Quantum Theory (New York: Dover); Robertson 1929 Phys. Rev. 34 127). This has profound effects not only on the microscopic but also on the macroscopic level of physical systems. The most familiar form of the uncertainty principle relates the uncertainties in position and linear momentum. Other manifestations include those relating uncertainty in energy to uncertainty in time duration, phase of an electromagnetic field to photon number and angular position to angular momentum (Vaccaro and Pegg 1990 J. Mod. Opt. 37 17; Barnett and Pegg 1990 Phys. Rev. A 41 3427). In this paper, we report the first observation of the last of these uncertainty relations and derive the associated states that satisfy the equality in the uncertainty relation. We confirm the form of these states by detailed measurement of the angular momentum of a light beam after passage through an appropriate angular aperture. The angular uncertainty principle applies to all physical systems and is particularly important for systems with cylindrical symmetry

Astronomy essentials

CERN Document Server

Brass, Charles O

2012-01-01

REA's Essentials provide quick and easy access to critical information in a variety of different fields, ranging from the most basic to the most advanced. As its name implies, these concise, comprehensive study guides summarize the essentials of the field covered. Essentials are helpful when preparing for exams, doing homework and will remain a lasting reference source for students, teachers, and professionals. Astronomy includes the historical perspective of astronomy, sky basics and the celestial coordinate systems, a model and the origin of the solar system, the sun, the planets, Kepler'

A search for quark compositeness at the LHC. Dijet angular distributions

International Nuclear Information System (INIS)

Usubov, Z.U.; Abdinov, O.B.

1999-01-01

The effects of dijet angular distributions coming from a model of quark compositeness are considered. The influence of the parton distribution function, calorimeter non-linearity and energy resolution is investigated. The data sensitivity to the quark compositeness scale for low and high LHC luminosity is studied

The Correlation between Pre-Service Science Teachers' Astronomy Achievement, Attitudes towards Astronomy and Spatial Thinking Skills

Science.gov (United States)

Türk, Cumhur

2016-01-01

The purpose of this study was to examine the changes in pre-service Science teachers' astronomy achievement, attitudes towards astronomy and skills for spatial thinking in terms of their years of study. Another purpose of the study was to find out whether there was correlation between pre-service teachers' astronomy achievement, attitudes towards…

Division B Commission 40: Radio Astronomy

NARCIS (Netherlands)

Chapman, Jessica M.; Giovaninni, Gabriele; Taylor, Russell; Carilli, Christopher; Hills, Richard; Hirabayashi, Hisashi; Jonas, Justin L.; Lazio, Joseph; Morganti, Raffaella; Nan, Rendong; Rubio, Monica; Shastri, Prjaval; Kellermann, Ken; Ekers, Ronald; Ohishi, Masatoshi

2016-01-01

IAU Commission 40 for Radio Astronomy (hereafter C40) brought together scientists and engineers who carry out observational and theoretical research in radio astronomy and who develop and operate the ground and space-based radio astronomy facilities and instrumentation. As of June 2015, the

Astronomy in Australia

Science.gov (United States)

Watson, F.; Couch, W.

2017-12-01

Australians have watched the sky for tens of thousands of years. The nineteenth century saw the foundation of government observatories in capital cities such as Sydney and Melbourne. While early twentieth-century astronomy focused largely on solar physics, the advent of radio astronomy at the end of the Second World War enabled Australia to take a leading role in the new science, with particular emphasis on low-frequency studies. Today, the radio quietness of its outback interior provides an excellent location for the Australian core of the Square Kilometre Array. Australian optical astronomy has flourished since the 1960s, with the 3.9-metre Anglo-Australian Telescope becoming the principal national facility in 1974. Access to ESO’s facilities at the La Silla Paranal Observatory is warmly welcomed by all Australian astronomers.

Research on teaching astronomy in the planetarium

CERN Document Server

Slater, Timothy F

2017-01-01

From a noted specialist in astronomy education and outreach, this Brief provides an overview of the most influential discipline-based science education research literature now guiding contemporary astronomy teaching. In recent years, systematic studies of effective and efficient teaching strategies have provided a solid foundation for enhancing college-level students’ learning in astronomy. Teaching astronomy and planetary science at the college-level was once best characterized as professor-centered, information-download lectures. Today, astronomy faculty are striving to drastically improve the learning environment by using innovative teaching approaches.  Uniquely, the authors have organized this book around strands of commonly employed astronomy teaching strategies to help readers, professors, and scholars quickly access the most relevant work while, simultaneously, avoiding the highly specialized, technical vocabulary of constructivist educational pedagogies unfamiliar to most astronomy professors. F...

Astronomy adventures and vacations how to get the most out of astronomy in your leisure time

CERN Document Server

Treadwell, Timothy

2017-01-01

This astronomy travel guide examines the many wonderful opportunities for experiencing the observing hobby. Amateur astronomy is often consigned to observing from home or from a local park, yet it can be much more. Tim Treadwell explores all the possibilities of astronomical and space-related activities that are available on day trips and longer vacations. These activities range from observatory visits and other simple ways to build an astronomy event into a holiday, to full blown specialized astronomy travel. Many trips give the opportunity to visit some of the world’s famous attractions. On most vacations it can be a matter of just taking a day (or night) out of your schedule to fit in an astronomy event, but larger, dedicated pilgrimages are also possible. How to make the most of astronomy potential on a holiday, whether observing on the beach in Hawaii with the Telescope Guy or visiting Star City in Russia, is covered in detail. Go to a star party, explore the national parks or see the northern lights! ...

Imaging escape gated MPWC for hard X-ray astronomy

Energy Technology Data Exchange (ETDEWEB)

Ubertini, P.; Bazzano, A.; Boccaccini, L.; La Padula, C.; Mastropietro, M.; Patriarca, R.; Polcaro, V.F.; Barbareschi, L.; Perotti, F.; Villa, G.

1983-11-15

A scientific forward step in the hard X-ray and soft gamma-ray astronomy will only be possible with the use of a new generation of space borne instruments. Their main characteristics have to be the two-dimensional imaging capability over a large collecting area and the fine spectral resolution in order to discriminate between the weak signal coming from cosmic sources to be detected and the strong background induced by cosmic rays, in the space environment, on the detector. To reach this goal we have developed a new hard X-ray position sensitive proportional counter operating with the escape gate technique in the range 15-150 keV, to be used together with a pseudo-random coded mask in order to obtain sky images. The detector is a high pressure (5 bar) xenon-argon-isobutane filled chamber with a spatial resolution of 30x2 mm and a spectral resolution of 5% at 60 keV on the sensitive area of 3000 cm/sup 2/.

Cooled CdZnTe detectors for X-ray astronomy

CERN Document Server

Bale, G; Seller, P; Lowe, B

1999-01-01

Recent results combining thermoelectrically cooled CdZnTe detectors with a low-noise Pentafet preamplifier are presented. Cooling between -30 deg. C and -40 deg. C reduces the leakage current of the detectors and allows the use of a pulsed reset preamplifier and long shaping times, significantly improving the energy resolution. Mn K subalpha X-rays at 5.9 keV have been observed with a resolution of less than 280 eV FWHM and a peak to background of more than 200:1. The Fano factor of the material has been estimated at 0.11+-0.012 at -40 deg. C. The detector requirement for X-ray astronomy will be a photon-counting imaging spectrometer. A 16x16 element, bump bonded pixel detector is described and results from a prototype silicon array presented. The detector is constructed with ASIC amplifiers with a system noise of <25 electrons rms and should give an energy resolution comparable to the Pentafet results presented here.

Tools of radio astronomy

CERN Document Server

Wilson, Thomas L; Hüttemeister, Susanne

2013-01-01

This 6th edition of “Tools of Radio Astronomy”, the most used introductory text in radio astronomy, has been revised to reflect the current state of this important branch of astronomy. This includes the use of satellites, low radio frequencies, the millimeter/sub-mm universe, the Cosmic Microwave Background and the increased importance of mm/sub-mm dust emission. Several derivations and presentations of technical aspects of radio astronomy and receivers, such as receiver noise, the Hertz dipole and  beam forming have been updated, expanded, re-worked or complemented by alternative derivations. These reflect advances in technology. The wider bandwidths of the Jansky-VLA and long wave arrays such as LOFAR and mm/sub-mm arrays such as ALMA required an expansion of the discussion of interferometers and aperture synthesis. Developments in data reduction algorithms have been included. As a result of the large amount of data collected in the past 20 years, the discussion of solar system radio astronomy, dust em...

Anisotropy of the Cosmic Microwave Background Radiation on Large and Medium Angular Scales

Science.gov (United States)

Houghton, Anthony; Timbie, Peter

1998-01-01

This grant has supported work at Brown University on measurements of the 2.7 K Cosmic Microwave Background Radiation (CMB). The goal has been to characterize the spatial variations in the temperature of the CMB in order to understand the formation of large-scale structure in the universe. We have concurrently pursued two measurements using millimeter-wave telescopes carried aloft by scientific balloons. Both systems operate over a range of wavelengths, chosen to allow spectral removal of foreground sources such as the atmosphere, Galaxy, etc. The angular resolution of approx. 25 arcminutes is near the angular scale at which the most structure is predicted by current models to be visible in the CMB angular power spectrum. The main goal is to determine the angular scale of this structure; in turn we can infer the density parameter, Omega, for the universe as well as other cosmological parameters, such as the Hubble constant.

Mass and Angular Distributions of Charged Dihadron Production

Energy Technology Data Exchange (ETDEWEB)

Cummings, Mary Clare [Michigan U.

1990-01-01

Experiment 711, conducted at Fermilab. provided a unique handle towards understanding valence quark scattering by studying pairs of single. charged, high transverse momentum hadrons produced in collisions of 800 GeV /c protons on fixed metal targets. The apparatus consisted of a double-arm spectrometer. calorimetrically triggered. with high momentum resolution and a large angular acceptance for all charge states of particle pairs. The experiment was designed to select those hadron pairs that carrted most of the momentum and energy of the underlying scattered quarks and gluons. The charge of such "leading" hadrons is correlated with the charge of the quark that produced it. Quantum Chromodynamics (QCD) assumes that the scattering behavior of quarks ts independent of their charge, or "flavour": Experiment 711 could test this assumption. Tilis dissertation descrtbes the analysis of the mass and angular distributions of hadron pair production for three separate charge states: +-, ++ and --. The angular distributions are found to deviate from theory predictions of flavour symmetry. Also. the mass cross sections indicate ratios of positive to negative hard-scattered particles that are larger than expected from theory. These results could warrant reconsideration of the assumptions and approximations currently made in leading-order QCD calculations.

Control of Rotational Energy and Angular Momentum Orientation with an Optical Centrifuge

Science.gov (United States)

Ogden, Hannah M.; Murray, Matthew J.; Mullin, Amy S.

2017-04-01

We use an optical centrifuge to trap and spin molecules to an angular frequency of 30 THz with oriented angular momenta and extremely high rotational energy and then investigate their subsequent collision dynamics with transient high resolution IR spectroscopy. The optical centrifuge is formed by combining oppositely-chirped pulses of 800 nm light, and overlapping them spatially and temporally. Polarization-sensitive Doppler-broadened line profiles characterize the anisotropic kinetic energy release of the super rotor molecules, showing that they behave like molecular gyroscopes. Studies are reported for collisions of CO2 super rotors with CO2, He and Ar. These studies reveal how mass, velocity and rotational adiabaticity impact the angular momentum relaxation and reorientation. Quantum scattering calculations provide insight into the J-specific collision cross sections that control the relaxation. NSF-CHE 105 8721.

Simulated cosmic microwave background maps at 0.5 deg resolution: Basic results

Science.gov (United States)

Hinshaw, G.; Bennett, C. L.; Kogut, A.

1995-01-01

We have simulated full-sky maps of the cosmic microwave background (CMB) anisotropy expected from cold dark matter (CDM) models at 0.5 deg and 1.0 deg angular resolution. Statistical properties of the maps are presented as a function of sky coverage, angular resolution, and instrument noise, and the implications of these results for observability of the Doppler peak are discussed. The rms fluctuations in a map are not a particularly robust probe of the existence of a Doppler peak; however, a full correlation analysis can provide reasonable sensitivity. We find that sensitivity to the Doppler peak depends primarily on the fraction of sky covered, and only secondarily on the angular resolution and noise level. Color plates of the simulated maps are presented to illustrate the anisotropies.

Mathematical Astronomy in India

Science.gov (United States)

Plofker, Kim

Astronomy in South Asia's Sanskrit tradition, apparently originating in simple calendric computations regulating the timing of ancient ritual practices, expanded over the course of two or three millennia to include detailed spherical models, an endless variety of astrological systems, and academic mathematics in general. Assimilating various technical models, methods, and genres from the astronomy of neighboring cultures, Indian astronomers created new forms that were in turn borrowed by their foreign counterparts. Always recognizably related to the main themes of Eurasian geocentric mathematical astronomy, Indian astral science nonetheless maintained its culturally distinct character until Keplerian heliocentrism and Newtonian mechanics replaced it in colonial South Asia's academic mainstream.

Discovering Astronomy Through Poetry

Science.gov (United States)

Mannone, John C.

2011-05-01

The literature is replete with astronomical references. And much of that literature is poetry. Using this fact, not only can the teacher infuse a new appreciation of astronomy, but also, the student has the opportunity to rediscover history through astronomy. Poetry can be an effective icebreaker in the introduction of new topics in physics and astronomy, as well as a point of conclusion to a lecture. This presentation will give examples of these things from the ancient literature (sacred Hebraic texts), classical literature (Homer's Iliad and Odyssey), traditional poetry (Longfellow, Tennyson and Poe) and modern literature (Frost, Kooser, and others, including the contemporary work of this author).

Warping the young stellar disc in the galactic centre

Czech Academy of Sciences Publication Activity Database

Šubr, Ladislav; Schovancová, J.

2008-01-01

Roč. 131, - (2008), s. 1-7 ISSN 1742-6588. [Universe under the microscope - astrophysics at high angular resolution. Bad Honnef, 21.04.2008-25.04.2008] R&D Projects: GA ČR GA205/07/0052 Institutional research plan: CEZ:AV0Z10030501 Keywords : circum-nuclear disc * zoung stars Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics

X-ray spectra and polarization from accreting black holes

Czech Academy of Sciences Publication Activity Database

Dovčiak, Michal; Goosmann, René; Karas, Vladimír; Matt, G.

2008-01-01

Roč. 131, - (2008), s. 1-6 ISSN 1742-6588. [The Universe under the Microscope – Astrophysics at High Angular Resolution. Bad Honnef, 21.04.2008-25.04.2008] R&D Projects: GA ČR GA205/07/0052 Institutional research plan: CEZ:AV0Z10030501 Keywords : black holes Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics

Transmission of Babylonian Astronomy to Other Cultures

Science.gov (United States)

Jones, Alexander

Babylonian astronomy and astrology were extensively transmitted to other civilizations in the second and first millennia BC. Greek astronomy in particular was largely shaped by knowledge of Babylonian observations and mathematical astronomy.

EVALUATION OF CONCEPTUAL FRAMEWORKS IN ASTRONOMY

Directory of Open Access Journals (Sweden)

David Pundak

2016-02-01

Full Text Available Even though astronomy is the oldest science, it is still an open question how to evaluate students’ understanding in astronomy. In spite of the fact that some methods and evaluation tools have been developed for that purpose, the sources of students' difficulties in astronomy are still unclear. This paper presents an investigation of the changes in conceptual frameworks in astronomy among 50 engineering students as a result of learning a general course in astronomy. A special tool called Conceptual Frameworks in Astronomy (CFA, which was initially used in 1989, was adopted to gather data for the present research. In its new version, the tool includes 23 questions and five to six optional answers to each question. Each of the answers characterizes one of the four conceptual frameworks: pre-scientific, geocentric, heliocentric and sidereal. These four conceptual frameworks act as a taxonomical system that enables us to evaluate astronomical understanding. The paper describes the background of the CFA, its development, and discusses its validity and reliability. Using the CFA we were able to: (1 identify the students’ conceptual frameworks at the beginning of the course and at its end, (2 to evaluate the students’ paradigmatic change following the course. It was found that the measure of the students’ improvement (gain index was g = 0.37. Approximately 45% of the students in the course improved their conceptual frameworks in astronomy and 26% deepened their understanding of the heliocentric or sidereal conceptual frameworks. The CFA can also be applied as an evaluation tool in all schools and institutions that teach astronomy.

The Angular Momentum of Baryons and Dark Matter Halos Revisited

Science.gov (United States)

Kimm, Taysun; Devriendt, Julien; Slyz, Adrianne; Pichon, Christophe; Kassin, Susan A.; Dubois, Yohan

2011-01-01

Recent theoretical studies have shown that galaxies at high redshift are fed by cold, dense gas filaments, suggesting angular momentum transport by gas differs from that by dark matter. Revisiting this issue using high-resolution cosmological hydrodynamics simulations with adaptive-mesh refinement (AMR), we find that at the time of accretion, gas and dark matter do carry a similar amount of specific angular momentum, but that it is systematically higher than that of the dark matter halo as a whole. At high redshift, freshly accreted gas rapidly streams into the central region of the halo, directly depositing this large amount of angular momentum within a sphere of radius r = 0.1R(sub vir). In contrast, dark matter particles pass through the central region unscathed, and a fraction of them ends up populating the outer regions of the halo (r/R(sub vir) > 0.1), redistributing angular momentum in the process. As a result, large-scale motions of the cosmic web have to be considered as the origin of gas angular momentum rather than its virialised dark matter halo host. This generic result holds for halos of all masses at all redshifts, as radiative cooling ensures that a significant fraction of baryons remain trapped at the centre of the halos. Despite this injection of angular momentum enriched gas, we predict an amount for stellar discs which is in fair agreement with observations at z=0. This arises because the total specific angular momentum of the baryons (gas and stars) remains close to that of dark matter halos. Indeed, our simulations indicate that any differential loss of angular momentum amplitude between the two components is minor even though dark matter halos continuously lose between half and two-thirds of their specific angular momentum modulus as they evolve. In light of our results, a substantial revision of the standard theory of disc formation seems to be required. We propose a new scenario where gas efficiently carries the angular momentum generated

Europe's Astronomy Teachers Meet at ESO

Science.gov (United States)

1994-12-01

European Association for Astronomy Education Formed A joint EU/ESO Workshop (1) on the Teaching of Astronomy in Europe was held at the ESO Headquarters from November 25-30, 1994, under the auspices of the 1994 European Week for Scientific Culture. More than 100 teachers from secondary schools in 17 European countries participated together with representatives of national ministries and local authorities, as well as professional astronomers. This meeting was the first of its kind ever held and was very successful. As a most visible and immediate outcome, the participants agreed to form the "European Association for Astronomy Education (EAAE)", uniting astronomy educators all over Europe into one network. A provisional Executive Committee of the EAAE was elected which will work towards the organisation of a constitutional conference within the next year. The participants unanimously adopted a "Declaration on the Teaching of Astronomy in Europe", specifying the overall aims and initial actions needed to achieve them. Astronomy: Science, Technology and Culture At the beginning of the Workshop the participants listened to lectures by several specialists about some of the most active fields of astronomy. The scientific sessions included topics as diverse as minor bodies in the solar system, nucleosynthesis, interstellar chemistry and cosmology. Then followed overviews of various recent advances in astronomical technology, some of which are already having direct impact on highly specialized sectors of European industry. They included the advanced use of computers in astronomy, for instance within image processing and data archiving, as well as a demonstration of remote observing. Discussing the cultural aspects, Nigel Calder (UK) and Hubert Reeves (France) emphasized the important role of astronomy in modern society, in particular its continuing influence on our perceptions of mankind's unique location in time and space. Teaching of Astronomy in European Countries

Demographics in Astronomy and Astrophysics

Science.gov (United States)

Ulvestad, James S.

2011-05-01

Astronomy has been undergoing a significant demographic shift over the last several decades, as shown by data presented in the 2000 National Research Council (NRC) report "Federal Funding of Astronomical Research," and the 2010 NRC report, "New Worlds, New Horizons in Astronomy and Astrophysics." For example, the number of advertised postdoctoral positions in astronomy has increased much more rapldly than the number of faculty positions, contributing to a holding pattern of early-career astronomers in multiple postdoctoral positions. This talk will summarize some of the current demographic trends in astronomy, including information about gender and ethnic diversity, and describe some of the possible implications for the future. I thank the members of the Astro2010 Demographics Study Group, as well as numerous white-paper contributors to Astro2010, for providing data and analyses.

Ancient Indian Astronomy in Introductory Texts

Science.gov (United States)

Narahari Achar, B. N.

1997-10-01

It is customary in introductory survey courses in astronomy to devote some time to the history of astronomy. In the available text books only the Greek contribution receives any attention. Apart from Stonehenge and Chichenitza pictures, contributions from Babylon and China are some times mentioned. Hardly any account is given of ancient Indian astronomy. Even when something is mentioned it is incomplete or incorrect or both. Examples are given from several text books currently available. An attempt is made to correct this situation by sketching the contributions from the earliest astronomy of India, namely Vedaanga Jyotisha.

Submillimetre-wave astronomy

International Nuclear Information System (INIS)

Beckman, J.E.; Phillips, J.P.

1982-01-01

Observations in the 100-1000-micron band and the instruments used to obtain them are discussed in contributions to the Submillimeter Wave Astronomy Conference held at Queen Mary College, London, in September 1981. The major subject areas covered are large-scale structure and radiative transfer within interstellar clouds, spectroscopic observations of molecular sources, interstellar chemistry, and submillimeter (SM) instrumentation. Reports are included on the formation of giant cloud complexes, cool molecular clouds, models for hot-centered and externally heated clouds, dust in Bok globules, airborne FIR and SM spectroscopy, rotational transitions of CH3OH and NH2 near 1.2 mm, high-velocity flows and molecular jets, FIR emissions from late-type galaxies, ion-grain collisions as a source of interstellar molecules, bandpass filters for SM astronomy, the SM receiver of the future, HF techniques in heterodyne astronomy, and the mm-wave cosmic background

The Cost of Astronomy

DEFF Research Database (Denmark)

Dorch, Bertil F.

Using Scopus and national sources, I have investigated the evolution of the cost of publishing in Danish astronomy on a fine scale over a number of years. I find that the number of publications per year from Danish astronomers increased by a factor of four during 15 years: naturally, the correspo......Using Scopus and national sources, I have investigated the evolution of the cost of publishing in Danish astronomy on a fine scale over a number of years. I find that the number of publications per year from Danish astronomers increased by a factor of four during 15 years: naturally......, the corresponding potential cost of publishing must have increased similarly. The actual realized cost of publishing in core journals are investigated for a high profile Danish astronomy research institutions. I argue that the situation is highly unstable if the current cost scenario continues, and I speculate...... that Danish astronomy is risking a scholarly communication collapse due to the combination of increasing subscription cost, increased research output, and increased direct publishing costs related to Open access and other page charges....

Music and Astronomy Under the Stars

Science.gov (United States)

Lubowich, D.

2008-11-01

Bring telescope to where the people are! Music and Astronomy Under the Stars is a public astronomy outreach program at community parks during and after free summer music concerts and outdoor movie nights. This project also includes daytime activities because there are some afternoon concerts and daylight children's concerts, and observations using remotely operated telescopes in cloudy weather. While there have been many astronomy outreach activities and telescope observations at city sidewalks and parks, this program targets a completely different audience---music lovers who are attending free summer concerts held in community parks. The music lovers who may never have visited a science museum, planetarium, or star party will be exposed to telescope observations and astronomy information with no additional travel costs. This program will permit the entire community to participate in telescope observations and view astronomical video information to enhance the public appreciation of astronomy. This program will also reach underrepresented and underserved groups (women, minorities, older adults). The population base for the initial target audience (Nassau and Suffolk Counties, New York) is 2,500,000. My partners are the Amateur Observers' Society of New York (AOS) and the Towns of Oyster Bay, Hempstead, North Hempstead, and Huntington. Music and Astronomy Under the Stars is program that should continue beyond the International Year of Astronomy 2009 (IYA2009) and can be expanded into a national program.

Rescuing Middle School Astronomy

Science.gov (United States)

Mayo, L. A.; Janney, D.

2010-12-01

There is a crisis in education at the middle school level (Spellings, 2006). Recent studies point to large disparities in middle school performance in schools with high minority populations. The largest disparities exist in areas of math and science. Astronomy has a universal appeal for K-12 students but is rarely taught at the middle school level. When it is taught at all it is usually taught in isolation with few references in other classes such as other sciences (e.g. physics, biology, and chemistry), math, history, geography, music, art, or English. The problem is greatest in our most challenged school districts. With scores in reading and math below national averages in these schools and with most state achievement tests ignoring subjects like astronomy, there is little room in the school day to teach about the world outside our atmosphere. Add to this the exceedingly minimal training and education in astronomy that most middle school teachers have and it is a rare school that includes any astronomy teaching at all. In this presentation, we show how to develop and offer an astronomy education training program for middle school teachers encompassing a wide range of educational disciplines that are frequently taught at the middle school level. The prototype for this program was developed and launched in two of the most challenged and diverse school systems in the country; D.C. Public Schools, and Montgomery County (MD) Public Schools.

Future Professional Communication in Astronomy II

Science.gov (United States)

Accomazzi, Alberto

The present volume gathers together the talks presented at the second colloquium on the Future Professional Communication in Astronomy (FPCAII), held at the Harvard-Smithsonian Center for Astrophysics (Cambridge, MA) on 13-14 April 2010. This meeting provided a forum for editors, publishers, scientists, librarians and officers of learned societies to discuss the future of the field. The program included talks from leading researchers and practitioners and drew a crowd of approximately 50 attendees from 10 countries. These proceedings contain contributions from invited and contributed talks from leaders in the field, touching on a number of topics. Among them: The role of disciplinary repositories such as ADS and arXiv in astronomy and the physical sciences; Current status and future of Open Access Publishing models and their impact on astronomy and astrophysics publishing; Emerging trends in scientific article publishing: semantic annotations, multimedia content, links to data products hosted by astrophysics archives; Novel approaches to the evaluation of facilities and projects based on bibliometric indicators; Impact of Government mandates, Privacy laws, and Intellectual Property Rights on the evolving digital publishing environment in astronomy; Communicating astronomy to the public: the experience of the International Year of Astronomy 2009.

Music and Astronomy Under the Stars 2009

Science.gov (United States)

Lubowich, D.

2010-08-01

Bring telescopes to where the people are! Music and Astronomy Under the Stars is a three-year NASA-funded astronomy outreach program at community parks during and after music concerts and outdoor family events—such as a Halloween Stars-Spooky Garden Walk. While there have been many astronomy outreach activities and telescope observations at city sidewalks and parks, this program targets a completely different audience: music lovers who are attending summer concerts held in community parks. These music lovers who may never have visited a science museum, planetarium, or star party are exposed to telescope observations and astronomy information with no additional travel costs. Music and Astronomy Under the Stars increased awareness, engagement, and interest in astronomy at classical, pop, rock, and ethnic music concerts. This program includes solar observing before the concerts, telescope observations including a live image projection system, an astronomical video presentation, and astronomy banners/posters. Approximately 500-16,000 people attended each event and 25% to 50% of the people at each event participated in the astronomy program. This program also reached underrepresented and underserved groups (women, minorities, older adults). The target audience (Nassau and Suffolk Counties, New York) is 2,900,000 people, which is larger than combined population of Atlanta, Boston, Denver, Minneapolis, and San Francisco. Although eleven events were planned in 2009, two were canceled due to rain and our largest event, the NY Philharmonic in the Park (attended by 67,000 people in 2008), was cancelled for financial reasons. Our largest event in 2009 was the Tanglewood Music Festival, Lenox MA, attended by 16,000 people where over 5000 people participated in astronomy activities. The Amateur Observers' Society of New York assisted with the NY concerts and the Springfield STARS astronomy club assisted at Tanglewood. In 2009 over 15,000 people participated in astronomy

Overview of lunar-based astronomy.

Science.gov (United States)

Smith, H. J.

The Moon offers both significant advantages and drawbacks for astronomy. Recognition of these characteristics can clarify the objectives toward which developments should be directed and can help to inhibit premature or excessive selling of lunar developments on the basis of astronomy.

The Very Large Array: Pioneering New Directions in Radio Astronomy

Science.gov (United States)

McKinnon, Mark

2018-01-01

The Very Large Array (VLA) started science operations in 1980 and was rechristened the Jansky VLA after a major upgrade to its electronics system was completed in 2012. The VLA plays a prominent role in scientific discovery through studies of the Solar System, star and planet formation, galaxy formation, and time domain astronomy. It has attained iconic status as one of the most scientifically productive telescopes on EarthIn 2017, three major initiatives were launched at the VLA with the goal of maintaining its leadership role and impact in radio astronomy in the near and long term future:1. In September, the VLA embarked upon the VLA Sky Survey (VLASS), the highest resolution survey ever undertaken at radio wavelengths. The survey was planned in consultation with the astronomy community and will be used to search for transients, study the polarization properties of extragalactic radio sources, and study highly obscured sources in our Galaxy.2. Detailed planning for a next generation VLA (ngVLA) began in earnest in 2017. The ngVLA will open a new window on the Universe through ultra-sensitive imaging of thermal line and continuum emission down to milliarcsecond resolution, as well as unprecedented broad-band continuum polarimetric imaging of non-thermal processes. A proposal for the instrument will be submitted to the 2020 Decadal Survey.3. A multi-year program to replace the 40+ year old infrastructure at the VLA site was initiated in 2017. The program includes the replacement of the VLA’s electrical infrastructure in 2018, improvements to the VLA rail system, and the replacement of heavy maintenance equipment.The VLA continued to play a major role in discovering and explaining the physics of transient phenomena in 2017, to include fast transients, such as fast radio bursts, and long time scale transients, such as novae, tidal disruption events, and gamma-ray bursts.More thorough descriptions of the VLASS and ngVLA, along with the science that can be done with

An imaging escape gated MPWC for hard X-ray astronomy

International Nuclear Information System (INIS)

Ubertini, P.; Bazzano, A.; Boccaccini, L.; La Padula, C.; Mastropietro, M.; Patriarca, R.; Polcaro, V.F.; Barbareschi, L.; Perotti, F.; Villa, G.; Butler, R.C.; Di Cocco, G.; Spada, G.; Charalambous, P.; Dean, A.J.; Stephen, J.B.

1983-01-01

A scientific forward step in the hard X-ray and soft gamma-ray astronomy will only be possible with the use of a new generation of space borne instruments. Their main characteristics have to be the two-dimensional imaging capability over a large collecting area and the fine spectral resolution in order to discriminate between the weak signal coming from cosmic sources to be detected and the strong background induced by cosmic rays, in the space environment, on the detector. To reach this goal we have developed a new hard X-ray position sensitive proportional counter operating with the escape gate technique in the range 15-150 keV, to be used together with a pseudo-random coded mask in order to obtain sky images. The detector is a high pressure (5 bar) xenon-argon-isobutane filled chamber with a spatial resolution of 30x2 mm and a spectral resolution of 5% at 60 keV on the sensitive area of 3000 cm 2 . (orig.)

Optical Angular Momentum

International Nuclear Information System (INIS)

Arimondo, Ennio

2004-01-01

For many years the Institute of Physics has published books on hot topics based on a collection of reprints from different journals, including some remarks by the editors of each volume. The book on Optical Angular Momentum, edited by L Allen, S M Barnett and M J Padgett, is a recent addition to the series. It reproduces forty four papers originally published in different journals and in a few cases it provides direct access to works not easily accessible to a web navigator. The collection covers nearly a hundred years of progress in physics, starting from an historic 1909 paper by Poynting, and ending with a 2002 paper by Padgett, Barnett and coworkers on the measurement of the orbital angular momentum of a single photon. The field of optical angular momentum has expanded greatly, creating an interdisciplinary attraction for researchers operating in quantum optics, atomic physics, solid state physics, biophysics and quantum information theory. The development of laser optics, especially the control of single mode sources, has made possible the specific design of optical radiation modes with a high degree of control on the light angular momentum. The editors of this book are important figures in the field of angular momentum, having contributed to key progress in the area. L Allen published an historical paper in 1999, he and M J Padgett (together with M Babiker) produced few years ago a long review article which is today still the most complete basic introduction to the angular momentum of light, while S M Barnett has contributed several high quality papers to the progress of this area of physics. The editors' choice provides an excellent overview to all readers, with papers classified into eight different topics, covering the basic principles of the light and spin and orbital angular momentum, the laboratory tools for creating laser beams carrying orbital angular momentum, the optical forces and torques created by laser beams carrying angular momentum on

Chaco astronomies

Science.gov (United States)

Martín López, Alejandro

2015-08-01

This presentation discusses the result of 18 years of ethnographic and ethnohistorical studies on Chaco astronomies. The main features of the systems of astronomical knowledge of the Chaco Aboriginal groups will be discussed. In particular we will discuss the relevance of the Milky Way, the role of the visibility of the Pleiades, the ways in which the celestial space is represented, the constitution of astronomical orientations in geographic space, etc. We also address a key feature of their vision of the cosmos: the universe is seen by these groups as a socio-cosmos, where humans and non-humans are related. These are therefore actually socio-cosmologies. We will link this to the theories of Chaco Aboriginal groups about power and political relations.We will discuss how the study of Aboriginal astronomies must be performed along with the studies about astronomies of Creole people and European migrants, as well as anthropological studies about the science teaching in the formal education system and by the mass media. In this form we will discuss the relevance of a very complex system of interethnic relations for the conformation of these astronomical representations and practices.We will also discuss the general methodological implications of this case for the ethnoastronomy studies. In particular we will talk about the advantages of a study of regional scope and about the key importance of put in contact the ethnoastronomy with contemporary issues in social sciences.We also analyze the importance of ethnoastronomy studies in relation to studies of sociology of science, especially astronomy. We also study the potential impact on improving formal and informal science curricula and in shaping effective policies to protect the tangible and intangible astronomical heritage in a context of respect for the rights of Aboriginal groups.

Multi-Institutional Collaborative Astronomy Education Research

Science.gov (United States)

Slater, T. F.; Slater, S. J.

2011-09-01

ASP, AAS, APS, and AAPT advocate that scientists should be engaged and acknowledged for successfully engaging in astronomy and physics education research and the scholarship of teaching because these efforts serve to improve pedagogical techniques and the evaluation of teaching. However, scientists have had the opportunity to pursue formal training in how to meaningfully engage in astronomy education research as an important scholarly endeavor. This special interest session for college and university physics and astronomy faculty, post-docs, and graduate students provided a forum to discuss the motivations, strategies, methodology, and publication routes for improving astronomy education through conducting rigorous science education research. Topics for discussion targeted the value of various education research questions, strengths and weaknesses of several different research design methodologies, strategies to successfully obtain Institutional Review Board approval to conduct education research on human subjects, and become more aware of how education research articles are created for publication in journals such as the Astronomy Education Review.

Development of the Advanced Energetic Pair Telescope (AdEPT) for Medium-Energy Gamma-Ray Astronomy

Science.gov (United States)

Hunter, Stanley D.; Bloser, Peter F.; Dion, Michael P.; McConnell, Mark L.; deNolfo, Georgia A.; Son, Seunghee; Ryan, James M.; Stecker, Floyd W.

2011-01-01

Progress in high-energy gamma-ray science has been dramatic since the launch of INTEGRAL, AGILE and FERMI. These instruments, however, are not optimized for observations in the medium-energy (approx.0.3< E(sub gamma)< approx.200 MeV) regime where many astrophysical objects exhibit unique, transitory behavior, such as spectral breaks, bursts, and flares. We outline some of the major science goals of a medium-energy mission. These science goals are best achieved with a combination of two telescopes, a Compton telescope and a pair telescope, optimized to provide significant improvements in angular resolution and sensitivity. In this paper we describe the design of the Advanced Energetic Pair Telescope (AdEPT) based on the Three-Dimensional Track Imager (3-DTI) detector. This technology achieves excellent, medium-energy sensitivity, angular resolution near the kinematic limit, and gamma-ray polarization sensitivity, by high resolution 3-D electron tracking. We describe the performance of a 30x30x30 cm3 prototype of the AdEPT instrument.

Highlighting the History of Astronomy in the Asia-Pacific Region

CERN Document Server

Nakamura, Tsuko; Strom, Richard G; ICOA-6 Conference

2011-01-01

This book provides readers with the results of recent research from some of the world's leading historians of astronomy on aspects of Arabic, Australian, Chinese, Japanese, and North and South American astronomy and astrophysics. It contains peer-reviewed papers gathered from the International Conferences on Oriental Astronomy 6 (ICO-6) with the chosen theme of "Highlighting the History of Astronomy in the Asia-Pacific Region." Of particular note are the sections on Arabic astronomy, Asian applied astronomy and the history of Australian radio astronomy, and the chapter on Peruvian astronomy. This title is a valuable complement for those with research interests in applied historical astronomy; archaeoastronomy; calendars, manuscripts, and star charts; historical instruments and observatories, and the history of radio astronomy.

Astronomy Week in Madeira, Portugal

Science.gov (United States)

Augusto, P.; Sobrinho, J. L.

2012-05-01

The outreach programme Semanas da Astronomia (Astronomy Weeks) is held in late spring or summer on the island of Madeira, Portugal. This programme has been attracting enough interest to be mentioned in the regional press/TV/radio every year and is now, without doubt, the astronomical highlight of the year on Madeira. We believe that this programme is a good case study for showing how to attract the general public to astronomy in a small (population 250 000, area 900 km2) and fairly isolated place such as Madeira. Our Astronomy Weeks have been different each year and have so far included exhibitions, courses, talks, a forum, documentaries, observing sessions (some with blackouts), music and an astro party. These efforts may contribute towards putting Madeira on the map with respect to observational astronomy, and have also contributed to the planned installation of two observatories in the island.

Lunar based gamma ray astronomy

International Nuclear Information System (INIS)

Haymes, R.C.

1985-01-01

Gamma ray astronomy represents the study of the universe on the basis of the electromagnetic radiation with the highest energy. Gamma ray astronomy provides a crucial tool for the understanding of astronomical phenomena, taking into account nucleosynthesis in supernovae, black holes, active galaxies, quasars, the sources of cosmic rays, neutron stars, and matter-antimatter annihilation. Difficulties concerning the conduction of studies by gamma ray astronomy are related to the necessity to perform such studies far from earth because the atmosphere is a source of gamma rays. Studies involving the use of gamma ray instruments in earth orbit have been conducted, and more gamma ray astronomy observations are planned for the future. Imperfections of studies conducted in low earth orbit could be overcome by estalishing an observatory on the moon which represents a satellite orbiting at 60 earth radii. Details concerning such an observatory are discussed. 5 references

PROCEEDINGS OF RIKEN BNL RESEARCH CENTER WORKSHOP ENTITLED: ''PARTON ORBITAL ANGULAR MOMENTUM'' VOLUME 81

International Nuclear Information System (INIS)

Bunce, G.; Fields, D.; Vogelsang, W.

2006-01-01

The joint UNM/RBRC 'Workshop on Parton Orbital Angular Momentum' was held on February 24th through 26th at the University of New Mexico Department of Physics and Astronomy in Albuquerque, New Mexico, and was sponsored by The University of New Mexico (Physics Department, New Mexico Center for Particle Physics, Dean of Arts and Sciences, and Office of the Vice Provost for Research and Economic Development) and the NUN-BNL Research Center. The workshop was motivated by recent and upcoming experimental data based on methods which have been proposed to access partonic angular momenta, including Deeply Virtual Compton Scattering, measuring the Sivers functions, and measuring helicity dependent k t in jets. Our desire was to clarify the state of the art in the theoretical understanding in this area, and to help define what might be learned about partonic orbital angular momenta Erom present and upcoming high precision data, particularly at RHIC, Jlab, COMPASS and HERMES. The workshop filled two rather full days of talks fiom both theorists and experimentalists, with a good deal of discussion during, and in between talks focusing on the relationship between the intrinsic transverse momentum, orbital angular momentum, and observables such as the Sivers Function. These talks and discussions were particularly illuminating and the organizers wish to express their sincere thanks to everyone for contributing to this workshop. Each workshop speaker is encouraged to select a few of the most important transparencies from his or her presentation, accompanied by a page of explanation. This material is collected at the end of the workshop by the organizer to form proceedings, which can therefore be available within a short time. To date there are eighty proceeding volumes available

Blazing the Trail for Astronomy Education Research

Science.gov (United States)

Bailey, Janelle M.; Lombardi, Doug

2015-01-01

Education research has long considered student learning of topics in astronomy and the space sciences, but astronomy education research as a sub-field of discipline-based education research is relatively new. Driven by a growing interest among higher education astronomy educators in improving the general education, introductory science survey…

Indian Astronomy: History of

Science.gov (United States)

Mercier, R.; Murdin, P.

2002-01-01

From the time of A macronryabhat under dota (ca AD 500) there appeared in India a series of Sanskrit treatises on astronomy. Written always in verse, and normally accompanied by prose commentaries, these served to create an Indian tradition of mathematical astronomy which continued into the 18th century. There are as well texts from earlier centuries, grouped under the name Jyotishaveda macronn d...

Astronomy for teachers: A South African Perspective

Science.gov (United States)

de Witt, Aletha; West, Marion; Leeuw, Lerothodi; Gouws, Eldrie

2015-08-01

South Africa has nominated Astronomy as a “flagship science” and aims to be an international Astronomy hub through projects such as the Square Kilometre Array (SKA) and the South African Large Telescope (SALT). These projects open up career opportunities in maths, science and engineering and therefore offers a very real door for learners to enter into careers in science and technology through Astronomy. However, the Trends in International Mathematics and Science Survey (TIMSS), the Global Competitiveness Report (GCR) and Annual National Assessment (ANA) have highlighted that South Africa’s Science and Mathematics education is in a critical condition and that South African learners score amongst the worst in the world in both these subjects. In South Africa Astronomy is generally regarded as the worst taught and most avoided Natural Science knowledge strand, and most teachers that specialised in Natural Sciences, never covered Astronomy in their training.In order to address these issues a collaborative project between the University of South Africa (UNISA) and the Hartebeesthoek Radio Astronomy Observatory (HartRAO) was initiated, which aims to assist teachers to gain more knowledge and skills so that they can teach Astronomy with confidence. By collaborating we aim to ensure that the level of astronomy development will be raised in both South Africa and the rest of Africa.With the focus on Teaching and Learning, the research was conducted within a quantitative paradigm and 600 structured questionnaires were administered to Natural Science teachers in Public primary schools in Gauteng, South Africa. This paper reports the findings of this research and makes recommendations on how to assist teachers to teach Astronomy with confidence.

Structure of high-resolution NMR spectra

CERN Document Server

Corio, PL

2012-01-01

Structure of High-Resolution NMR Spectra provides the principles, theories, and mathematical and physical concepts of high-resolution nuclear magnetic resonance spectra.The book presents the elementary theory of magnetic resonance; the quantum mechanical theory of angular momentum; the general theory of steady state spectra; and multiple quantum transitions, double resonance and spin echo experiments.Physicists, chemists, and researchers will find the book a valuable reference text.

Cultural Astronomy in the Armenian Highland

Science.gov (United States)

Farmanyan, S. V.; Suvaryan, Yu. M.; Mickaelian, A. M. (Eds.)

2016-12-01

The book contains 29 articles of the Proceedings of the Young Scientists Conference "Cultural Astronomy in the Armenian Highland" held at the Armenian National Academy of Sciences on 20-23 June 2016. It consists of 4 main sections: "Introductory", "Cultural Astronomy", "Archaeoastronomy", "Scientific Tourism and Journalism, Astronomical Education and Amateur Astronomy". The book may be interesting to astronomers, culturologists, philologists, linguists, historians, archaeologists, art historians, ethnographers and to other specialists, as well as to students.

Technology Needs for Gamma Ray Astronomy

Science.gov (United States)

Gehrels, Neil

2011-01-01

Gamma ray astronomy is currently in an exciting period of multiple missions and a wealth of data. Results from INTEGRAL, Fermi, AGILE, Suzaku and Swift are making large contributions to our knowledge of high energy processes in the universe. The advances are due to new detector and imaging technologies. The steps to date have been from scintillators to solid state detectors for sensors and from light buckets to coded aperture masks and pair telescopes for imagers. A key direction for the future is toward focusing telescopes pushing into the hard X-ray regime and Compton telescopes and pair telescopes with fine spatial resolution for medium and high energy gamma rays. These technologies will provide finer imaging of gamma-ray sources. Importantly, they will also enable large steps forward in sensitivity by reducing background.

Development of Small-Pixel CZT Detectors for Future High-Resolution Hard X-ray Missions

Science.gov (United States)

Beilicke, Matthias

Owing to recent breakthroughs in grazing incidence mirror technology, next-generation hard X-ray telescopes will achieve angular resolutions of between 5 and 10 arc seconds - about an order of magnitude better than that of the NuSTAR hard X-ray telescope. As a consequence, the next generation of hard X-ray telescopes will require pixelated hard X- ray detectors with pixels on a grid with a lattice constant of between 120 and 240 um. Additional detector requirements include a low energy threshold of less than 5 keV and an energy resolution of less than 1 keV. The science drivers for a high angular-resolution hard X-ray mission include studies and measurements of black hole spins, the cosmic evolution of super-massive black holes, AGN feedback, and the behavior of matter at very high densities. We propose a R&D research program to develop, optimize and study the performance of 100-200 um pixel pitch CdTe and Cadmium Zinc Telluride (CZT) detectors of 1-2 mm thickness. Our program aims at a comparison of the performance achieved with CdTe and CZT detectors, and the optimization of the pixel, steering grid, and guard ring anode patterns. Although these studies will use existing ASICs (Application Specific Integrated Circuits), our program also includes modest funds for the development of an ultra-low noise ASIC with a 2-D grid of readout pads that can be directly bonded to the 100-200 um pixel pitch CdTe and CZT detectors. The team includes the Washington University group (Prof. M. Beilicke and Co-I Prof. H.S.W. Krawczynski et al.), and co-investigator G. De Geronimo at Brookhaven National Laboratory (BNL). The Washington University group has a 10 year track record of innovative CZT detector R&D sponsored by the NASA Astronomy and Physics Research and Analysis (APRA) program. The accomplishments to date include the development of CZT detectors with pixel pitches between 350 um and 2.5 mm for the ProtoExist, EXIST, and X-Calibur hard X-ray missions with some of the best

Focal Plane Detectors for the Advanced Gamma-Ray Imaging System (AGIS)

Science.gov (United States)

Wagner, R. G.; Byrum, K.; Drake, G.; Funk, S.; Otte, N.; Smith, A.; Tajima, H.; Williams, D.

2009-05-01

The Advanced Gamma-Ray Imaging System (AGIS) is a concept for the next generation observatory in ground-based very high energy gamma-ray astronomy. It is being designed to achieve a significant improvement in sensitivity compared to current Imaging Air Cherenkov Telescope (IACT) Arrays. One of the main requirements in order that AGIS fulfills this goal will be to achieve higher angular resolution than current IACTs. Simulations show that a substantial improvement in angular resolution may be achieved if the pixel size is reduced to 0.05 deg, i.e. two to three times smaller than for current IACT cameras. Here we present results from testing of alternatives being considered for AGIS, including both silicon photomultipliers (SiPMs) and multi-anode photomultipliers (MAPMTs).

Visual lunar and planetary astronomy

CERN Document Server

Abel, Paul G

2013-01-01

With the advent of CCDs and webcams, the focus of amateur astronomy has to some extent shifted from science to art. The object of many amateur astronomers is now to produce “stunning images” that, although beautiful, are not intended to have scientific merit. Paul Abel has been addressing this issue by promoting visual astronomy wherever possible – at talks to astronomical societies, in articles for popular science magazines, and on BBC TV’s The Sky at Night.   Visual Lunar and Planetary Astronomy is a comprehensive modern treatment of visual lunar and planetary astronomy, showing that even in the age of space telescopes and interplanetary probes it is still possible to contribute scientifically with no more than a moderately priced commercially made astronomical telescope.   It is believed that imaging and photography is somehow more objective and more accurate than the eye, and this has led to a peculiar “crisis of faith” in the human visual system and its amazing processing power. But by anal...

Second generation stationary digital breast tomosynthesis system with faster scan time and wider angular span.

Science.gov (United States)

Calliste, Jabari; Wu, Gongting; Laganis, Philip E; Spronk, Derrek; Jafari, Houman; Olson, Kyle; Gao, Bo; Lee, Yueh Z; Zhou, Otto; Lu, Jianping

2017-09-01

The aim of this study was to characterize a new generation stationary digital breast tomosynthesis system with higher tube flux and increased angular span over a first generation system. The linear CNT x-ray source was designed, built, and evaluated to determine its performance parameters. The second generation system was then constructed using the CNT x-ray source and a Hologic gantry. Upon construction, test objects and phantoms were used to characterize system resolution as measured by the modulation transfer function (MTF), and artifact spread function (ASF). The results indicated that the linear CNT x-ray source was capable of stable operation at a tube potential of 49 kVp, and measured focal spot sizes showed source-to-source consistency with a nominal focal spot size of 1.1 mm. After construction, the second generation (Gen 2) system exhibited entrance surface air kerma rates two times greater the previous s-DBT system. System in-plane resolution as measured by the MTF is 7.7 cycles/mm, compared to 6.7 cycles/mm for the Gen 1 system. As expected, an increase in the z-axis depth resolution was observed, with a decrease in the ASF from 4.30 mm to 2.35 mm moving from the Gen 1 system to the Gen 2 system as result of an increased angular span. The results indicate that the Gen 2 stationary digital breast tomosynthesis system, which has a larger angular span, increased entrance surface air kerma, and faster image acquisition time over the Gen 1 s-DBT system, results in higher resolution images. With the detector operating at full resolution, the Gen 2 s-DBT system can achieve an in-plane resolution of 7.7 cycles per mm, which is better than the current commercial DBT systems today, and may potentially result in better patient diagnosis. © 2017 American Association of Physicists in Medicine.

Gamma astronomy

International Nuclear Information System (INIS)

Cesarsky, C.; Cesarsky, J.P.

1986-01-01

This article overviews the gamma astronomy research. Sources already observed, and what causes to give to them; the galactic radiation and its interpretation; techniques already used and current projects [fr

Astronomy in Second Life

Directory of Open Access Journals (Sweden)

Gauthier, A.

2007-10-01

Full Text Available Second Life (SL is a multi-user virtual environment that is not limited to adult social entertainment. SL is also a 3D playground for innovative instructors and education/outreach professionals in the sciences. Astronomy and space science have a presence in SL, but it could be so much more. This paper describes some of the current astronomy themed spaces in SL and briefly discusses future innovations.

Extragalactic astronomy

International Nuclear Information System (INIS)

Sersic, J.L.

1982-01-01

This book condenses the author's yearly semester lectures on 'Extra galactic Astronomy' held almost without interruption over two decades at Cordoba University for students of Astronomy. After a first chapter on Morphology and Classification of galaxies, the second gives most of the basic information about normal galaxies as individuals. Active galaxies are described in chapter III whilst chapter IV deals with the mutual relationship between galaxies and their environment. The Scale of distance is considered in chapter V. Distance indicators are introduced and several conflicting viewpoints of different schools are presented. Chapter VI deals with Cosmology, just to give the necessary elements for chapter VII where the relation between gravitational instability and galaxy formation is discussed. Chapter VIII is an appendix containing additional notes. (Auth.)

Multimedia Astronomy Communication: Effectively Communicate Astronomy to the Desired Audience

Science.gov (United States)

Star Cartier, Kimberly Michelle; Wright, Jason

2017-01-01

A fundamental aspect of our jobs as scientists is communicating our work to others. In this, the field of astronomy holds the double-edged sword of ubiquitous fascination: the topic has been of interest to nearly the entire global population at some point in their lives, yet the learning curve is steep within any subfield and rife with difficult-to-synthesize details. Compounding this issue is the ever-expanding array of methods to reach people in today's Communications Era. Each communication medium has its own strengths and weaknesses, is appropriate in different situations, and requires its own specific skillset in order to maximize its functionality. Despite this, little attention is given to training astronomers in effective communication techniques, often relying on newcomers to simply pick up the ability by mimicking others and assuming that a firm grasp on the subject matter will make up for deficiencies in communication theory. This can restrict astronomers to a narrow set of communication methods, harming both the communicators and the audience who may struggle to access the information through those media.Whether writing a research paper to academic peers or giving an astronomy talk to a pubic audience, successfully communicating a scientific message requires more than just an expert grasp on the topic. A communicator must understand the makeup and prior knowledge of the desired audience, be able to break down the salient points of the topic into pieces that audience can digest, select and maximize upon a medium to deliver the message, and frame the message in a way that hooks the audience and compels further interest. In this work we synthesize the requirements of effective astronomy communication into a few key questions that every communicator needs to answer. We then discuss some of the most common media currently used to communicate astronomy, give both effective and poor examples of utilizing these media to communicate astronomy, and provide key

Angular correlation methods

International Nuclear Information System (INIS)

Ferguson, A.J.

1974-01-01

An outline of the theory of angular correlations is presented, and the difference between the modern density matrix method and the traditional wave function method is stressed. Comments are offered on particular angular correlation theoretical techniques. A brief discussion is given of recent studies of gamma ray angular correlations of reaction products recoiling with high velocity into vacuum. Two methods for optimization to obtain the most accurate expansion coefficients of the correlation are discussed. (1 figure, 53 references) (U.S.)

The Explorer program for astronomy and astrophysics

International Nuclear Information System (INIS)

Savage, B.D.; Becklin, E.E.; Cassinelli, J.P.; Dupree, A.K.; Elliot, J.L.; Hoffmann, W.F.; Hudson, H.S.; Jura, M.; Kurfess, J.; Murray, S.S.

1986-01-01

This report was prepared to provide NASA with a strategy for proceeding with Explorer-class programs for research in space astronomy and astrophysics. The role of Explorers in astronomy and astrophysics and their past accomplishments are discussed, as are current and future astronomy and astrophysics Explorers. Specific cost needs for an effective Explorer program are considered

International Olympiad on Astronomy and Astrophysics

Science.gov (United States)

Soonthornthum, B.; Kunjaya, C.

2011-01-01

The International Olympiad on Astronomy and Astrophysics, an annual astronomy and astrophysics competition for high school students, is described. Examples of problems and solutions from the competition are also given. (Contains 3 figures.)

Archaeo- and Cultural Astronomy in Armenia

Science.gov (United States)

Farmanyan, Sona V.; Mickaelian, Areg M.

2015-08-01

We present a general overview on Armenian Archaeoastronomy and Astronomy in Culture to mention and summarize some activities and related organizations involved. Armenia is rather rich in archaeoastronomy and culture, including calendars, rock art, mythology, etc. Archaeoastronomical issues in Armenia include: Zodiac Constellations (believed to be introduced for the first time in the Armenian Highland); Ancient Observatories; Armenian Rock Art; Ancient Armenian Calendar and other (medieval) calendars; Astronomical Terms and Names; Records of Astronomical Events by ancient Armenians; Anania Shirakatsi’s (612-685) Astronomical Heritage; Medieval Sky Maps and Astronomical Devices. During the recent years, we have organized a number of meetings, where archaeoastronomy was involved: Joint European and National Astronomy Meeting (JENAM-2007), Special Session #6: “Archaeoastronomy” (2007), ArAS VIII Annual Meeting “Astronomy and Society”, Session “Archaeoastronomy” (2009), Archaeoastronomical meeting “Astronomical Heritage in the National Culture” dedicated to Anania Shirakatsi’s 1400th anniversary (2012), Meeting “Relation of Astronomy to other Sciences, Culture and Society” (RASCS), Sessions“Archaeoastronomy” and “Astronomy in Culture” (2014). Along with Byurakan Astrophysical Observatory (BAO), there are several other institutions related to Archaeoastronomy and Astronomy in Culture: Institute of History, Institute of Archaeology and Ethnography, Institute of Literature, Institute of Language, Matenadaran (Institute of Ancient Manuscripts). We have introduced a section “Archaeoastronomy and Astronomy in Culture” in the newsletter of Armenian Astronomical Society (ArAS). This is to strengthen ArAS activities and to widen our knowledge in this area, to encourage and establish collaborations with other scientists related to these subjects; historians, archaeologists, ethnographers, philologists, linguists, artists and other

UV astronomy throughout the ages: a historical perspective

Science.gov (United States)

Linsky, Jeffrey L.

2018-05-01

Astronomers have long recognized the critical need for ultraviolet imaging, photometry and spectroscopy of stars, planets, and galaxies, but this need could not be satisfied without access to space and the development of efficient instrumentation. When UV measurements became feasible, first with rockets and then with satellites, major discoveries came rapidly. It is true in the UV spectral region as in all others, that significant increases in sensitivity, spectral resolution, and time domain coverage have led to significant new understanding of astrophysical phenomena. I will describe a selection of these discoveries made in each of three eras: (1) the early history of rocket instrumentation and Copernicus, the first UV satellite, (2) the discovery phase pioneered by the IUE, FUSE and EUVE satellites, and (3) the full flowering of UV astronomy with the successful operation of HST and its many instruments. I will also mention a few areas where future UV instrumentation could lead to new discoveries. This review concentrates on developments in stellar and interstellar UV spectroscopy; the major discoveries in galactic, extragalactic, and solar system research are beyond the scope of this review. The important topic of UV technologies and detectors, which enable the remarkable advances in UV astronomy are also not included in this review.

Angular-momentum-dominated electron beams and flat-beam generation

International Nuclear Information System (INIS)

Sun, Yin-e

2005-01-01

In the absence of external forces, if the dynamics within an electron beam is dominated by its angular momentum rather than other effects such as random thermal motion or self Coulomb-repulsive force (i.e., space-charge force), the beam is said to be angular-momentum-dominated. Such a beam can be directly applied to the field of electron-cooling of heavy ions; or it can be manipulated into an electron beam with large transverse emittance ratio, i.e., a flat beam. A flat beam is of interest for high-energy electron-positron colliders or accelerator-based light sources. An angular-momentum-dominated beam is generated at the Fermilab/NICADD photoinjector Laboratory (FNPL) and is accelerated to an energy of 16 MeV. The properties of such a beam is investigated systematically in experiment. The experimental results are in very good agreement with analytical expectations and simulation results. This lays a good foundation for the transformation of an angular-momentum-dominated beam into a flat beam. The round-to-flat beam transformer is composed of three skew quadrupoles. Based on a good knowledge of the angular-momentum-dominated beam, the quadrupoles are set to the proper strengths in order to apply a total torque which removes the angular momentum, resulting in a flat beam. For bunch charge around 0.5 nC, an emittance ratio of 100 ± 5 was measured, with the smaller normalized root-mean-square emittance around 0.4 mm-mrad. Effects limiting the flat-beam emittance ratio are investigated, such as the chromatic effects in the round-to-flat beam transformer, asymmetry in the initial angular-momentum-dominated beam, and space-charge effects. The most important limiting factor turns out to be the uncorrelated emittance growth caused by space charge when the beam energy is low, for example, in the rf gun area. As a result of such emittance growth prior to the round-to-flat beam transformer, the emittance ratio achievable in simulation decreases from orders of thousands to

Angular-momentum-dominated electron beams and flat-beam generation

Energy Technology Data Exchange (ETDEWEB)

Sun, Yin-e [Univ. of Chicago, IL (United States)

2005-06-01

In the absence of external forces, if the dynamics within an electron beam is dominated by its angular momentum rather than other effects such as random thermal motion or self Coulomb-repulsive force (i.e., space-charge force), the beam is said to be angular-momentum-dominated. Such a beam can be directly applied to the field of electron-cooling of heavy ions; or it can be manipulated into an electron beam with large transverse emittance ratio, i.e., a flat beam. A flat beam is of interest for high-energy electron-positron colliders or accelerator-based light sources. An angular-momentum-dominated beam is generated at the Fermilab/NICADD photoinjector Laboratory (FNPL) and is accelerated to an energy of 16 MeV. The properties of such a beam is investigated systematically in experiment. The experimental results are in very good agreement with analytical expectations and simulation results. This lays a good foundation for the transformation of an angular-momentum-dominated beam into a flat beam. The round-to-flat beam transformer is composed of three skew quadrupoles. Based on a good knowledge of the angular-momentum-dominated beam, the quadrupoles are set to the proper strengths in order to apply a total torque which removes the angular momentum, resulting in a flat beam. For bunch charge around 0.5 nC, an emittance ratio of 100 ± 5 was measured, with the smaller normalized root-mean-square emittance around 0.4 mm-mrad. Effects limiting the flat-beam emittance ratio are investigated, such as the chromatic effects in the round-to-flat beam transformer, asymmetry in the initial angular-momentum-dominated beam, and space-charge effects. The most important limiting factor turns out to be the uncorrelated emittance growth caused by space charge when the beam energy is low, for example, in the rf gun area. As a result of such emittance growth prior to the round-to-flat beam transformer, the emittance ratio achievable in simulation decreases from orders of thousands to

Characterization of the angular memory effect of scattered light in biological tissues.

Science.gov (United States)

Schott, Sam; Bertolotti, Jacopo; Léger, Jean-Francois; Bourdieu, Laurent; Gigan, Sylvain

2015-05-18

High resolution optical microscopy is essential in neuroscience but suffers from scattering in biological tissues and therefore grants access to superficial brain layers only. Recently developed techniques use scattered photons for imaging by exploiting angular correlations in transmitted light and could potentially increase imaging depths. But those correlations ('angular memory effect') are of a very short range and should theoretically be only present behind and not inside scattering media. From measurements on neural tissues and complementary simulations, we find that strong forward scattering in biological tissues can enhance the memory effect range and thus the possible field-of-view by more than an order of magnitude compared to isotropic scattering for ∼1 mm thick tissue layers.

Astronomy education through interactive materials

Science.gov (United States)

Voelzke, Marcos Rincon; Antunes de Macêdo, Josué

2015-08-01

This study presents results of a survey conducted at the Federal Institution of Education, Science and Technology in the North of Minas Gerais (IFNMG), and aimed to investigate the potentialities of the use of interactive materials in the teaching of astronomy. An advanced training course with involved learning activities about basic concepts of astronomy was offered to thirty-two Licenciate students in Physics, Mathematics and Biological Sciences, using the mixed methodology, combined with the three pedagogical moments. Among other aspects, the viability of the use of resources was noticed, involving digital technologies and interactive materials on teaching of astronomy, which may contribute to the broadening of methodological options for future teachers and meet their training needs.

Teaching Astronomy and Computation with Gaia: A New Curriculum for an Extra-curricular High School Program

Science.gov (United States)

Schwab, Ellianna; Faherty, Jacqueline K.; Barua, Prachurjya; Cooper, Ellie; Das, Debjani; Simone-Gonzalez, Luna; Sowah, Maxine; Valdez, Laura; BridgeUP: STEM

2018-01-01

BridgeUP: STEM (BridgeUP) is a program at the American Museum of Natural History (AMNH) that seeks to empower women by providing early-career scientists with research fellowships and high-school aged women with instruction in computer science and algorithmic methods. BridgeUP achieves this goal by employing post-baccalaureate women as Helen Fellows, who, in addition to conducting their own scientific research, mentor and teach high school students from the New York City area. The courses, targeted at early high-school students, are designed to teach algorithmic thinking and scientific methodology through the lens of computational science. In this poster we present the new BridgeUP astronomy curriculum created for 9th and 10th grade girls.The astronomy course we present is designed to introduce basic concepts as well as big data manipulation through a guided exploration of Gaia (DR1). Students learn about measuring astronomical distances through hands-on lab experiments illustrating the brightness/distance relationship, angular size calculations of the height of AMNH buildings, and in-depth Hertzsprung-Russell Diagram activities. Throughout these labs, students increase their proficiency in collecting and analyzing data, while learning to build and share code in teams. The students use their new skills to create color-color diagrams of known co-moving clusters (Oh et al. 2017) in the DR1 dataset using Python, Pandas and Matplotlib. We discuss the successes and lessons learned in the first implementation of this curriculum and show the preliminary work of six of the students, who are continuing with computational astronomy research over the current school year.

Exploring Metacogntive Visual Literacy Tasks for Teaching Astronomy

Science.gov (United States)

Slater, Timothy F.; Slater, S.; Dwyer, W.

2010-01-01

Undoubtedly, astronomy is a scientific enterprise which often results in colorful and inspirational images of the cosmos that naturally capture our attention. Students encountering astronomy in the college classroom are often bombarded with images, movies, simulations, conceptual cartoons, graphs, and charts intended to convey the substance and technological advancement inherent in astronomy. For students who self-identify themselves as visual learners, this aspect can make the science of astronomy come alive. For students who naturally attend to visual aesthetics, this aspect can make astronomy seem relevant. In other words, the visual nature that accompanies much of the scientific realm of astronomy has the ability to connect a wide range of students to science, not just those few who have great abilities and inclinations toward the mathematical analysis world. Indeed, this is fortunate for teachers of astronomy, who actively try to find ways to connect and build astronomical understanding with a broad range of student interests, motivations, and abilities. In the context of learning science, metacognition describes students’ self-monitoring, -regulation, and -awareness when thinking about learning. As such, metacognition is one of the foundational pillars supporting what we know about how people learn. Yet, the astronomy teaching and learning community knows very little about how to operationalize and support students’ metacognition in the classroom. In response, the Conceptual Astronomy, Physics and Earth sciences Research (CAPER) Team is developing and pilot-testing metacogntive tasks in the context of astronomy that focus on visual literacy of astronomical phenomena. In the initial versions, students are presented with a scientifically inaccurate narrative supposedly describing visual information, including images and graphical information, and asked to assess and correct the narrative, in the form of peer evaluation. To guide student thinking, students

The Advanced Gamma-ray Imaging System (AGIS): Simulation Studies

Science.gov (United States)

Fegan, Stephen; Buckley, J. H.; Bugaev, S.; Funk, S.; Konopelko, A.; Maier, G.; Vassiliev, V. V.; Simulation Studies Working Group; AGIS Collaboration

2008-03-01

The Advanced Gamma-ray Imaging System (AGIS) is a concept for the next generation instrument in ground-based very high energy gamma-ray astronomy. It has the goal of achieving significant improvement in sensitivity over current experiments. We present the results of simulation studies of various possible designs for AGIS. The primary characteristics of the array performance, collecting area, angular resolution, background rejection, and sensitivity are discussed.

The Advanced Gamma-ray Imageing System (AGIS): Simulation Design Studies

Science.gov (United States)

Bugaev, V.; Buckley, J.; Digel, S.; Fegan, S.; Funk, S.; Konopelko, A.; Krawczynski, H.; Lebohec, S.; Maier, G.; Vassiliev, V.

2008-04-01

We present design studies for AGIS, a proposed array of ˜100 imaging atmospheric Cherenkov telescopes for gamma-rays astronomy in the 40GeV to 100 TeV energy regime. We describe optimization studies for the array configuration, pixel size and field of view aimed at achieving the best sensitivity over the entire energy range and best angular resolution for a fixed project total cost.

What next for astronomy?

Science.gov (United States)

Williams, Robert

2009-12-01

"Astronomy is in the midst of a golden age," wrote Catherine Cesarsky, my predecessor as president of the International Astronomical Union (IAU), earlier this year in Physics World (March pp22-24). I believe that is certainly true and it is an opportunity that we must take full advantage of. Astronomy is one of the great ways to bring science to the public - the images of the universe obtained using the Hubble Space Telescope, for example, are full of beauty. Astronomy is all about us. Indeed, the Earth and the life on it have developed from the cosmos, and the sky is the one laboratory that all humanity shares equally and that is accessible to all. There is little about the subject that appeals to fear - except, perhaps, the occasional killer asteroid. So what better science to inspire and educate people that what we do not know is definitely worth knowing?

Strategies for Teaching Astronomy

Science.gov (United States)

Bennett, J.

2000-12-01

No matter whether you are teaching school children, undergraduates, or colleagues, a few key strategies are always useful. I will present and give examples for the following five key strategies for teaching astronomy. 1. Provide a Contextual Framework: It is much easier to learn new facts or concepts if they can be ``binned" into some kind of pre-existing mental framework. Unless your listeners are already familiar with the basic ideas of modern astronomy (such as the hierarchy of structure in the universe, the scale of the universe, and the origin of the universe), you must provide this before going into the details of how we've developed this modern picture through history. 2. Create Conditions for Conceptual Change: Many people hold misconceptions about astronomical ideas. Therefore we cannot teach them the correct ideas unless we first help them unlearn their prior misconceptions. 3. Make the Material Relevant: It's human nature to be more interested in subjects that seem relevant to our lives. Therefore we must always show students the many connections between astronomy and their personal concerns, such as emphasizing how we are ``star stuff" (in the words of Carl Sagan), how studying other planets helps us understand our own, and so on. 4. Limit Use of Jargon: The number of new terms in many introductory astronomy books is larger than the number of words taught in many first courses in foreign language. This means the books are essentially teaching astronomy in a foreign language, which is a clear recipe for failure. We must find ways to replace jargon with plain language. 5. Challenge Your Students: Don't dumb your teaching down; by and large, students will rise to meet your expectations, as long as you follow the other strategies and practice good teaching.

Women's and Men's Career Choices in Astronomy and Astrophysics

Science.gov (United States)

Ivie, Rachel; White, Susan; Chu, Raymond Y.

2016-01-01

The Longitudinal Study of Astronomy Graduate Students (LSAGS) arose from the 2003 Women in Astronomy Conference, where it was noted that a majority of young members of the American Astronomical Society were women. The astronomy community wishes to make every effort to retain young women in astronomy, so they commissioned a longitudinal study to be…

Making Space for Specialized Astronomy Resources

Science.gov (United States)

MacMillan, D.

2007-10-01

With the growth of both free and subscription-based resources, articles on astronomy have never been easier to find. Locating the best and most current materials for any given search, however, now requires multiple tools and strategies dependent on the query. An analysis of the tools currently available shows that while astronomy is well-served by Google Scholar, Scopus and Inspec, its literature is best accessed through specialized resources such as ADS (Astrophysics Data System). While no surprise to astronomers, this has major implications for those of us who teach information literacy skills to astronomy students and work in academic settings where astronomy is just one of many subjects for which our non-specialist colleagues at the reference desk provide assistance. This paper will examine some of the implications of this analysis for library instruction, reference assistance and training, and library webpage development.

Astronomy in the Big Data Era

Directory of Open Access Journals (Sweden)

Yanxia Zhang

2015-05-01

Full Text Available The fields of Astrostatistics and Astroinformatics are vital for dealing with the big data issues now faced by astronomy. Like other disciplines in the big data era, astronomy has many V characteristics. In this paper, we list the different data mining algorithms used in astronomy, along with data mining software and tools related to astronomical applications. We present SDSS, a project often referred to by other astronomical projects, as the most successful sky survey in the history of astronomy and describe the factors influencing its success. We also discuss the success of Astrostatistics and Astroinformatics organizations and the conferences and summer schools on these issues that are held annually. All the above indicates that astronomers and scientists from other areas are ready to face the challenges and opportunities provided by massive data volume.

SMART-X: Square Meter, Arcsecond Resolution Telescope for X-rays

Science.gov (United States)

Vikhlinin, Alexey; SMART-X Collaboration

2013-04-01

SMART-X is a concept for a next-generation X-ray observatory with large-area, 0.5" angular resolution grazing incidence adjustable X-ray mirrors, high-throughput critical angle transmission gratings, and X-ray microcalorimeter and CMOS-based imager in the focal plane. High angular resolution is enabled by new technology based on controlling the shape of mirror segments using thin film piezo actuators deposited on the back surface. Science applications include observations of growth of supermassive black holes since redshifts of ~10, ultra-deep surveys over 10's of square degrees, galaxy assembly at z=2-3, as well as new opportunities in the high-resolution X-ray spectroscopy and time domains. We also review the progress in technology development, tests, and mission design over the past year.

Developing Astronomy Research and Education in the Philippines

Science.gov (United States)

Sese, R. M. D.; Kouwenhoven, M. B. N. Thijs

2015-03-01

In the past few years, the Philippines has been gradually developing its research and educational capabilities in astronomy and astrophysics. In terms of astronomy development, it is still lagging behind several neighboring Southeast Asian countries such as Indonesia, Thailand and Malaysia, while it is advanced with respect to several others. One of the main issues hampering progress is the scarcity of trained professional Filipino astronomers, as well as long-term visions for astronomy development. Here, we will be presenting an overview of astronomy education and research in the country. We will discuss the history and current status of astronomy in the Philippines, including all levels of education, outreach and awareness activities, as well as potential areas for research and collaborations. We also discuss issues that need to be addressed to ensure sustainable astronomy development in the Philippines. Finally, we discuss several ongoing and future programs aimed at promoting astronomy research and education. In essence, the work is a precursor of a possible white paper which we envision to submit to the Department of Science and Technology (DOST) in the near future, with which we aim to further convince the authorities of the importance of astrophysics. With the support of the International Astronomical Union (IAU), this may eventually lead to the creation of a separate astronomy agency in the Philippines.

Optical angular momentum and atoms.

Science.gov (United States)

Franke-Arnold, Sonja

2017-02-28

Any coherent interaction of light and atoms needs to conserve energy, linear momentum and angular momentum. What happens to an atom's angular momentum if it encounters light that carries orbital angular momentum (OAM)? This is a particularly intriguing question as the angular momentum of atoms is quantized, incorporating the intrinsic spin angular momentum of the individual electrons as well as the OAM associated with their spatial distribution. In addition, a mechanical angular momentum can arise from the rotation of the entire atom, which for very cold atoms is also quantized. Atoms therefore allow us to probe and access the quantum properties of light's OAM, aiding our fundamental understanding of light-matter interactions, and moreover, allowing us to construct OAM-based applications, including quantum memories, frequency converters for shaped light and OAM-based sensors.This article is part of the themed issue 'Optical orbital angular momentum'. © 2017 The Author(s).

Optical angular momentum and atoms

Science.gov (United States)

2017-01-01

Any coherent interaction of light and atoms needs to conserve energy, linear momentum and angular momentum. What happens to an atom’s angular momentum if it encounters light that carries orbital angular momentum (OAM)? This is a particularly intriguing question as the angular momentum of atoms is quantized, incorporating the intrinsic spin angular momentum of the individual electrons as well as the OAM associated with their spatial distribution. In addition, a mechanical angular momentum can arise from the rotation of the entire atom, which for very cold atoms is also quantized. Atoms therefore allow us to probe and access the quantum properties of light’s OAM, aiding our fundamental understanding of light–matter interactions, and moreover, allowing us to construct OAM-based applications, including quantum memories, frequency converters for shaped light and OAM-based sensors. This article is part of the themed issue ‘Optical orbital angular momentum’. PMID:28069766

2011 Astronomy Day at McDonald Observatory

Science.gov (United States)

Preston, Sandra; Hemeway, M.; Wetzel, M.

2012-01-01

Our philosophy is that everyday is Astronomy Day because the McDonald Observatory's Frank N. Bash Visitors Center is open 362 days a year. So, how did we create a special celebration for the "Astronomy Day” declared by the Astronomical League? During September 26-29 we conducted 20 videoconferences and served 12,559 students with "Astronomy Day” programming. Connect2Texas provides bridging for a network of Texas-based museums and cultural, historical, and scientific organizations that offer educational content to schools throughout the state via videoconferencing. Connect2Texas connected McDonald Observatory to 334 schools; most of these schools were in Texas, but schools in a dozen other states also participated. While most schools had a "view-only" connection, at least 20 of the schools had interactive connections, whereby the students could ask questions of the presenter. Connect2Texas also collects evaluation information from the participating schools that we will use to produce a report for our funders and make modifications to future programs as need be. The videoconferences were offered free of charge. The theme for the 2011 Astronomy Day program was the Year of the Solar System, which aligns with NASA's theme for 2011 and 2012. By aligning with this NASA theme, we could leverage NASA artwork and materials to both advertise and enrich the learning experience. Videoconference materials also included pre- and post-videoconference assessment sheets, an inquiry based activity, and pre- and post-videoconference activities, all of which were made available online. One of the lessons learned from past Astronomy Day videoconferences is that the days the Astronomical League declares as "Astronomy Day” are not always good days for Texas schools to participate. So, we choose an Astronomy Day that meets the needs of Texas schools and our schedule - so any day can be Astronomy Day. 2011 Astronomy Day was made possible by The Meyer-Levy Charitable Trust.

Reflections on the astronomy of Glasgow

CERN Document Server

Clarke, David

2013-01-01

How Astronomy contributed to the educational enlightenment of Glasgow, to its society and to its commerce. The words 'Astronomy' and 'Glasgow' seem an incongruous juxtaposition, and yet the two are closely linked over 500 years of history. This is a tale of enlightenment and scientific progress at both institutional and public levels. Combined with the ambitions of civic commerce, it is a story populated with noteworthy personalities and intense rivalries.It is remarkable to realise that the first Astronomy teaching in the Glasgow 'Colledge' presented an Earth-centred Universe, prior to the Co

Advances in astronomy and astrophysics 9

CERN Document Server

Kopal, Zdenek

1972-01-01

Advances in Astronomy and Astrophysics, Volume 9 covers reviews on the advances in astronomy and astrophysics. The book presents reviews on the Roche model and its applications to close binary systems. The text then describes the part played by lunar eclipses in the evolution of astronomy; the classical theory of lunar eclipses; deviations from geometrical theory; and the methods of photometric observations of eclipses. The problems of other phenomena related in one way or another to lunar eclipses are also considered. The book further tackles the infrared observation on the eclipsed moon, as

Interactive Materials In The Teaching Of Astronomy

Science.gov (United States)

Macêdo, J. A.; Voelzke, M. R.

2014-10-01

This study presents results of a survey conducted at the Federal Institution of Education, Science and Technology in the North of Minas Gerais (IFNMG), and aimed to investigate the potentialities of the use of interactive materials in the teaching of astronomy. An advanced training course with involved learning activities about basic concepts of astronomy was offered to thirty-two Licenciate students in Physics, Mathematics and Biological Science. The following steps were to be taken: i) analysis of the pedagogical projects (PPC) of the licenciates at the IFNMG, research locus of its Campus Januária; ii) analysis of students' preconceptions about astronomy and digital technologies, identified by the application of an initial questionnaire; iii) preparation of the course taking into account the students' previous knowledge; iv) application of the education proposal developed under part-time presence modality, using various interactive tools; v) application and analysis of the final questionnaire. The test was conducted with the qualitative and quantitative methodology, combined with a content analysis. The results indicated that in the IFNMG only the licenciate-course in physics includes astronomy content diluted in various subjects of the curriculum; the rates of students prior knowledge in relation to astronomy was low; an evidence of meaningful learning of the concepts related to astronomy, and of viability of resource use involving digital technologies in the Teaching of astronomy, which may contribute to the broadening of methodological options of future teachers and meet their training needs.

47 CFR 2.107 - Radio astronomy station notification.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 1 2010-10-01 2010-10-01 false Radio astronomy station notification. 2.107....107 Radio astronomy station notification. (a) Pursuant to No. 1492 of Article 13 and Section F of Appendix 3 to the international Radio Regulations (Geneva, 1982), operators of radio astronomy stations...

Virtual Reality Astronomy Education Using AAS WorldWide Telescope and Oculus Rift

Science.gov (United States)

Weigel, A. David; Moraitis, Christina D.

2017-01-01

The Boyd E. Christenberry Planetarium at Samford University (Birmingham, AL) offers family friendly, live, and interactive planetarium presentations that educate the public on topics from astronomy basics to current cutting edge astronomical discoveries. With limited funding, it is not possible to provide state of the art planetarium hardware for these community audiences. In a society in which many people, even young children, have access to high resolution smart phones and highly realistic video games, it is important to leverage cutting-edge technology to intrigue young and old minds alike. We use an Oculus Rift virtual reality headset running AAS WorldWide Telescope software to visualize 3D data in a fully immersive environment. We create interactive experiences and videos to highlight astronomical concepts and also to communicate the beauty of our universe. The ease of portability enables us to set up at Virtual Reality (VR) experience at various events, festivals, and even in classrooms to provide a community outreach that a fixed planetarium cannot. This VR experience adds the “wow” factor that encourages children and adults to engage in our various planetarium events to learn more about astronomy and continue to explore the final frontier of space. These VR experiences encourages our college students to participate in our astronomy education resulting in increased interest in STEM fields, particularly physics and math.

Cultural Astronomy in Armenia and in the World

Science.gov (United States)

Farmanyan, S. V.; Mickaelian, A. M.

2016-12-01

Cultural Astronomy is the reflection of sky events in various fields of nations' culture. In foreign literature, this field is also called "Astronomy in Culture" or "Astronomy and Culture". Cultural astronomy is the set of interdisciplinary fields studying the astronomical systems of current or ancient societies and cultures. It is manifested in Religion, Mythology, Folklore, Poetry, Art, Linguistics and other fields. In recent years, considerable attention has been paid to this sphere, particularly international organizations were established, conferences are held and journals are published. Armenia is also rich in cultural astronomy. The present paper focuses on Armenian archaeoastronomy and cultural astronomy, including many creations related to astronomical knowledge; calendars, rock art, mythology, etc. On the other hand, this subject is rather poorly developed in Armenia; there are only individual studies on various related issues (especially many studies related to Anania Shirakatsi) but not coordinated actions to manage this important field of investigation.

Book Review: Astronomy: A Self-Teaching Guide, 6th Edition

Science.gov (United States)

Marigza, R. N., Jr.

2009-03-01

The sixth edition of Moche's book is up-to-date with the latest in astronomy. It contains accurate astronomical data on stars and constellations. The topics are incorporated with web site addresses for the reader to expand his/her knowledge and see high-resolution images of the celestial targets. This edition incorporates new discoveries and suggestions made prior to the first editions. Among the new developments is the twenty-first-century research into black holes, active galaxies and quasars, searches for life in space, origin and structure of our universe, and the latest in ground and space telescopes.

Astronomers Without Borders: A Global Astronomy Community

Science.gov (United States)

Simmons, M.

2011-10-01

Astronomers Without Borders (AWB) brings together astronomy enthusiasts of all types - amateur astronomers, educators, professionals and "armchair" astronomers for a variety of online and physicalworld programs. The AWB web site provides social networking and a base for online programs that engage people worldwide in astronomy activities that transcend geopolitical and cultural borders. There is universal interest in astronomy, which has been present in all cultures throughout recorded history. Astronomy is also among the most accessible of sciences with the natural laboratory of the sky being available to people worldwide. There are few other interests for which people widely separated geographically can engage in activities involving the same objects. AWB builds on those advantages to bring people together. AWB also provides a platform where projects can reach a global audience. AWB also provides unique opportunities for multidisciplinary collaboration in EPO programs. Several programs including The World at Night, Global Astronomy Month and others will be described along with lessons learned.

Communicating astronomy with the public in Cuba

Science.gov (United States)

Alvarez, O.

2008-06-01

Communicating astronomy with the public to produce attractive materials for a broad audience on TV is a difficult job in a third world country. One way of developing effective communication in fields like astronomy, astrophysics, and cosmology whilst connecting the professional astronomer with a majority of the people is to combine the knowledge of the scientist with the most spectacular TV production methods of first world countries: integrating, through commentary and analysis, astronomy and science into the public debate of lay citizens. Here I present my ten years of experience of presenting a TV programme devoted to general science outreach. I also comment on the progress of the construction of the new planetarium, a cultural centre for science and technology, to be opened as part of the commemoration activities for the 2009 International Year of Astronomy. It is hoped to guide the interest of the people of Cuba towards basic science and astronomy in the most populated and frequented area of the country.

Humanising Astronomy

Science.gov (United States)

Levin, S.

2008-06-01

Universe Awareness (UNAWE) is an international programme that aims to expose underprivileged children (in the age group 4-10) to the inspirational aspects of astronomy. We are currently at the stage of developing materials that will be utilised in a diverse range of environments. This paper explores UNAWE's particular approach to developing tools which includes not only indigenous and folkloric astronomical knowledge, but also the culture of transmission of such knowledge. A specific understanding and explanation of the Universe, the Sun, Moon and stars is present in every culture and can be found contained in its history, legends and belief systems. By consciously embracing different ways of knowing the Universe and not uniquely the rational model, UNAWE places the humanising potential of astronomy at the centre of its purpose. Whilst inspiring curiosity, pride and a sense of ownership in one's own cultural identity, such an approach also exposes children to the diversity of other peoples and their cultures as well as the unifying aspects of our common scientific heritage. The means of creating and delivering the astronomy programme are as relevant to the desired educational outcomes as the content. The challenge in the design of materials is to communicate this stimulating message to the very young. Respect for alternative values systems, the need for dialogue and community participation, and where possible the production of materials using local resources is emphasised. This paper touches recent experiences liaising with communities in India, South Africa, Tunisia, Venezuela and Colombia.

Accessible Astronomy.

Science.gov (United States)

Glickstein, Neil

1994-01-01

Describes the development of a theme-based, multidisciplinary course. The article partitions into the following sections: (1) Constructing the Course; (2) Putting the Ideas to Work; (3) Connecting Science and Society; and (4) The Arts and Astronomy. (ZWH)

The Effect of Media on Preservice Science Teachers' Attitudes toward Astronomy and Achievement in Astronomy Class

Science.gov (United States)

Bektasli, Behzat

2013-01-01

Studies show that it is hard to change students' attitudes toward science. This study specifically explored if media affect preservice science teachers' attitudes toward astronomy and their astronomy achievement. The sample for the pilot study consisted of 196 preservice science and mathematics teachers for attitude assessment and 230 preservice…

Science and Mathematics in Astronomy

Science.gov (United States)

Woolack, Edward

2009-01-01

A brief historical introduction to the development of observational astronomy will be presented. The close historical relationship between the successful application of mathematical concepts and advances in astronomy will be presented. A variety of simple physical demonstrations, hands-on group activities, and puzzles will be used to understand how the properties of light can be used to understand the contents of our universe.

Handbook Of X-ray Astronomy

Science.gov (United States)

Arnaud, Keith A.; Smith, R. K.; Siemiginowska, A.; Edgar, R. J.; Grant, C. E.; Kuntz, K. D.; Schwartz, D. A.

2011-09-01

This poster advertises a book to be published in September 2011 by Cambridge University Press. Written for graduate students, professional astronomers and researchers who want to start working in this field, this book is a practical guide to x-ray astronomy. The handbook begins with x-ray optics, basic detector physics and CCDs, before focussing on data analysis. It introduces the reduction and calibration of x-ray data, scientific analysis, archives, statistical issues and the particular problems of highly extended sources. The book describes the main hardware used in x-ray astronomy, emphasizing the implications for data analysis. The concepts behind common x-ray astronomy data analysis software are explained. The appendices present reference material often required during data analysis.

Extragalactic astronomy and cosmology an introduction

CERN Document Server

Schneider, Peter

2015-01-01

Accounting for the astonishing developments in the field of Extragalactic Astronomy and Cosmology, this second edition has been updated and substantially expanded. Starting with the description of our home galaxy, the Milky Way, this cogently written textbook introduces the reader to the astronomy of galaxies, their structure, active galactic nuclei, evolution and large scale distribution in the Universe. After an extensive and thorough introduction to modern observational and theoretical cosmology, the focus turns to the formation of structures and astronomical objects in the early Universe. The basics of classical astronomy and stellar astrophysics needed for extragalactic astronomy are provided in the appendix. The new edition incorporates some of the most spectacular results from new observatories like the Galaxy Evolution Explorer, Herschel, ALMA, WMAP and Planck, as well as new instruments and multi-wavelength campaigns which have expanded our understanding of the Universe and the objects populating it....

Methodological pluralism in the teaching of Astronomy

Science.gov (United States)

de Macedo, Josué Antunes; Voelzke, Marcos Rincon

2015-04-01

This paper discusses the feasibility of using a teaching strategy called methodological pluralism, consisting of the use of various methodological resources in order to provide a meaningful learning. It is part of a doctoral thesis, which aims to investigate contributions to the use of traditional resources combined with digital technologies, in order to create autonomy for future teachers of Natural Sciences and Mathematics in relation to themes in Astronomy. It was offered an extension course at the "Federal Institution of Education, Science and Technology" in the North of Minas Gerais (FINMG), Campus Januaria, for thirty-two students of licentiate courses in Physics, Mathematics and Biological Sciences, involving themes of Astronomy, in order to search and contribute to improving the training of future teachers. The following aspects are used: the mixed methodology, with pre-experimental design, combined with content analysis. The results indicate the rates of students' prior knowledge in relation to Astronomy was low; meaningful learning indications of concepts related to Astronomy, and the feasibility of using digital resources Involving technologies, articulated with traditional materials in the teaching of Astronomy. This research sought to contribute to the initial teacher training, especially in relation to Astronomy Teaching, proposing new alternatives to promote the teaching of this area of knowledge, extending the methodological options of future teachers.

A New Online Astronomy Resource for Education and Outreach

Science.gov (United States)

Impey, C. D.; Hardegree-Ullman, K. K.; Patikkal, A.; Srinathan, A.; Austin, C. L.; Ganesan, N. K.; Guvenen, B. C.

2013-01-01

A new web site called "Teach Astronomy" (http://www.teachastronomy.com) has been created to serve astronomy instructors and their students, amateur astronomers, and members of the public interested in astronomy. The

Test of special resolution and trigger efficiency

CERN Document Server

Benhammou, Y

2015-01-01

The forthcoming luminosity upgrade of LHC to super-LHC (sLHC) will increase the expected background rate in the forward region of the ATLAS Muon Spectrometer by approximately the factor of five. Some of the present Muon Spectrometer components will fail to cope with these high rates and will have to be replaced. The results of a test of a device consisting of Thin Gap Chambers (TGC) and a fast small-diameter Muon Drift Tube Chamber (sMDT) using the 180 GeV/c muons at the SPS-H8 muon beam at CERN are presented. The goal of the test was to study the combined TGC-sMDT system as tracking and triggering device in the ATLAS muon spectrometer after high-luminosity upgrades of the LHC. The analysis of the recorded data shows a very good correlation between the TGC and sMDT track position and inclination. This technology offers the combination of trigger and tracking and has good angular and spatial resolutions. The angular resolution is 0.4 mrad for each system individually. For the spatial resolution, the width of t...

Network for Astronomy School Education

Science.gov (United States)

Deustua, Susana E.; Ros, R. M.; Garcia, B.

2014-01-01

The Network for Astronomy School Education Project (NASE) was developed in response to the IAU's most recent 10 Years Strategic Plan to increase the efforts of the IAU in schools. NASE's mission is to stimulate teaching astronomy in schools, through professional development of primary and secondary school science teachers in developing and emerging countries. NASE's organizational principle is to build capacity by providing courses for three years in cooperation with a Local Organizing Committee (Local NASE Group). The Local NASE Group consists of 6-8 local university professors and education professional who will promote astronomy activities and organize future courses in subsequent years in their region of their country. NASE philosophy is to introduce low-tech astronomy, and has thus developed an a suite of activities that can be carried out with inexpensive, quotidian materials. Supporting these activities is a text for teachers, plus a complete set of instructional materials for each topic. These materials are available in English and Spanish, with future editions available in Chinese and Portuguese. We describe and discuss NASE activities in Central and South America from 2009 to the present.

Multiverso: Rock'n'Astronomy

Science.gov (United States)

Caballero, J. A.

2012-05-01

In the last few years, there have been several projects involving astronomy and classical music. But have a rock band ever appeared at a science conference or an astronomer at a rock concert? We present a project, Multiverso, in which we mix rock and astronomy, together with poetry and video art (Caballero, 2010). The project started in late 2009 and has already reached tens of thousands people in Spain through the release of an album, several concert-talks, television, radio, newspapers and the internet.

Covering the Standards: Astronomy Teachers' Preparation and Beliefs

Science.gov (United States)

Plummer, Julia D.; Zahm, Valerie M.

2010-01-01

An online survey of science teachers and interviews with curriculum directors were used to investigate the coverage of astronomy in middle and high schools in the greater Philadelphia region. Our analysis looked beyond astronomy elective courses to uncover all sources of astronomy education in secondary schools. We focused on coverage of state…

Highlights of Astronomy, Vol. 16

Science.gov (United States)

Montmerle, Thierry

2015-04-01

Part I. Invited Discourses: 1. The Herschel view of star formation; 2. Past, present and future of Chinese astronomy; 3. The zoo of galaxies; 4. Supernovae, the accelerating cosmos, and dark energy; Part II. Joint Discussion: 5. Very massive stars in the local universe; 6. 3-D views of the cycling Sun in stellar context; 7. Ultraviolet emission in early-type galaxies; 8. From meteors and meteorites to their parent bodies: current status and future developments; 9. The connection between radio properties and high-energy emission in AGNs; 10. Space-time reference systems for future research; Part III. Special Sessions: 11. Origin and complexity of massive star clusters; 12. Cosmic evolution of groups and clusters of galaxies; 13. Galaxy evolution through secular processes; 14. New era for studying interstellar and intergalactic magnetic fields; 15. The IR view of massive stars: the main sequence and beyond; 16. Science with large solar telescopes; 17. The impact hazard: current activities and future plans; 18. Calibration of star-formation rate measurements across the electromagnetic spectrum; 19. Future large scale facilities; 20. Dynamics of the star-planet relations strategic plan and the Global Office of Astronomy for Development; 21. Strategic plan and the Global Office of Astronomy for Development; 22. Modern views of the interstellar medium; 23. High-precision tests of stellar physics from high-precision photometry; 24. Communicating astronomy with the public for scientists; 25. Data intensive astronomy; 26. Unexplained spectral phenomena in the interstellar medium; 27. Light pollution: protecting astronomical sites and increasing global awareness through education.

News clippings for introductory astronomy

Science.gov (United States)

Bobrowsky, Matthew

1999-09-01

Most students entering our introductory astronomy course for nonscience majors arrive not merely lacking scientific facts-they also have misconceptions about the nature of science, and many have a handicapping ``science anxiety'' (in addition to math anxiety). So I have added a ``current science'' requirement to our introductory course. Each student must compile a file of five astronomy news articles taken from readily available sources.

X-Ray Optics: Past, Present, and Future

Science.gov (United States)

Zhang, William W.

2010-01-01

X-ray astronomy started with a small collimated proportional counter atop a rocket in the early 1960s. It was immediately recognized that focusing X-ray optics would drastically improve both source location accuracy and source detection sensitivity. In the past 5 decades, X-ray astronomy has made significant strides in achieving better angular resolution, large photon collection area, and better spectral and timing resolutions, culminating in the three currently operating X-ray observatories: Chandra, XMM/Newton, and Suzaku. In this talk I will give a brief history of X-ray optics, concentrating on the characteristics of the optics of these three observatories. Then I will discuss current X-ray mirror technologies being developed in several institutions. I will end with a discussion of the optics for the International X-ray Observatory that I have been developing at Goddard Space Flight Center.

“Astronomy for a Better World”: IAU/OAD Task Force One Activities to Develop Astronomy Education and Research at Universities in the Developing World

Science.gov (United States)

Guinan, Edward Francis; Kolenberg, Katrien

2015-08-01

The Task Force (1) on Astronomy for Universities & Research (TF-1) was established in 2012 as part of the IAU Office of Astronomy for Development (OAD). This Task Force drives activities related to astronomy education and research at universities mainly in the developing world. Astronomy is used to stimulate research and education in STEM fields and to develop and promote astronomy in regions of the world where there is little or no astronomy. There is also potential for developing research in the historical and cultural aspects of astronomy which may prove important for stimulating an interest in the subject in communities where there is yet no established interest in the science.Since the establishment of the OAD, over 25 TF-1 programs have been funded (or partially funded) to support a wide variety of interesting and innovative astronomy programs in Africa, Asia, South-East Asia, Middle-East, and in South & Central America. Nearly every aspect of development has been supported. These programs include supporting: regional astronomy training schools, specialized workshops, research visits, university twinning programs, distance learning projects, university astronomy curriculum development, as well as small telescope and equipment grants. In addition, a large new program - Astrolab - was introduced (by J-P De Greve and Michele Gerbaldi) to bring starlight” into the class room. In the Astrolab program students carry out and reduce CCD photometry secured by them using remotely controlled telescopes. Results from pilot programs will be discussed.OAD TF-1 programs will be discussed along with future plans for improving and expanding these programs to bring astronomy education and research to a greater number of people and indeed to use Astronomy for a Better World. Information and advice will also be provided about applying for support in the future.

Automated and angular time-synchronized directional gamma-ray scintillation sensor

International Nuclear Information System (INIS)

Kronenberg, S.; Brucker, G.J.

1998-01-01

The authors' previous research resulted in directional sensors for gamma rays and X rays that have a 4π solid angle of acceptance and, at the same time, a high angular resolution that is limited only by their ability to measure small angles. Angular resolution of ∼1 s of arc was achieved. These sensors are capable of operating and accurately detecting high and very low intensity radiation patterns. Such a system can also be used to image broad area sources and their scattering patterns. The principle of operation and design of directional sensors used in this study was described elsewhere; however, for convenience, a part of that text is repeated here. It was shown analytically that the angular distribution of radiation incident on the sensor is proportional to the first derivative of the scan data, that is, of the events' count rate versus orientation of the detector. The previously published results were obtained with a annual operating system. The detector assembly was set at a specific angle, and a pulse rate count was made. This was repeated at numerous other angles of orientation, a time-consuming and labor-intensive process. Recently, the authors automated this system, which is based on the detection of scintillations. The detector, which consists of a stack of plates of Lucite, plastic scintillator, and lead foils, rotates by means of a motor in front of a stationary photomultiplier tube (PMT). One revolution per second was chosen for the motor. At time zero, a trigger indicates that a revolution has started. The angle of orientation of the detector in the laboratory system is proportional to the time during one revolution. The process repeats itself a desired number of times. The trigger signal initiates a scan of a multichannel scalar (MCS). The detector assembly is allowed to rotate in the radiation field, and the MCS scans are repeated in an accumulated mode of operation until enough events are collected for the location of the radiation source to be

Astronomy and astrology

Science.gov (United States)

Zarka, Philippe

2011-06-01

Astrology meets a large success in our societies, from the private to the political sphere as well as in the media, in spite of the demonstrated inaccuracy of its psychological as well as operational predictions. We analyse here the relations between astrology and astronomy, as well as the criticisms opposed by the latter to the former. We show that most of these criticisms are weak. Much stronger ones emerge from the analysis of the astrological practice compared to the scientific method, leading us to conclude to the non-scientificity of astrology. Then we return to the success of astrology, and from its analysis we propose a renewed (and prophylactic) rôle for astronomy in society.

X-ray astronomy

International Nuclear Information System (INIS)

Giacconi, R.; Setti, G.

1980-01-01

This book contains the lectures, and the most important seminars held at the NATO meeting on X-Ray astronomy in Erice, July 1979. The meeting was an opportune forum to discuss the results of the first 8-months of operation of the X-ray satellite, HEAO-2 (Einstein Observatory) which was launched at the end of 1978. Besides surveying these results, the meeting covered extragalactic astronomy, including the relevant observations obtained in other portions of the electromagnetic spectrum (ultra-violet, optical, infrared and radio). The discussion on galactic X-ray sources essentially covered classical binaries, globular clusters and bursters and its significance to extragalactic sources and to high energy astrophysics was borne in mind. (orig.)

High-energy astronomy in the U.K

International Nuclear Information System (INIS)

Pounds, K.A.

1976-01-01

Highlights of British research on radio galaxies, x-ray astronomy, and hot black holes are described. The prospects for international collaboration on space projects, in particular x-ray astronomy, are discussed

L'astronomie et son histoire

CERN Document Server

Roy, Jean-René

1982-01-01

Le livre de Jean-René Roy nous présente une vaste synthèse des connaissances présentes en astronomie. Le grand mérite du livre est de dérouler son sujet en parallèle avec une histoire de l'astronomie. Le côté historique est ici beaucoup plus qu'un luxe. Il redonne leurs dimensions vraies aux réponses qu'apporte l'astronomie. Pour bien sentir la nature d'une étape franchie, il faut aussi avoir vécu la situation telle qu'elle se présentait avant. Et les fiches personnelles incluses dans le livre ont l'intérêt de nous rapprocher encore plus du "" feu de l'action "". Écrit dans un style direct et

No Child Left Behind and High School Astronomy

Science.gov (United States)

Krumenaker, Larry

2009-01-01

Astronomy was a required subject in the first American secondary level schools, the academies of the 18th century. When these were supplanted a century later by public high schools, astronomy still was often required, subsumed into courses of Natural Philosophy. Reasons given at that time to support astronomy as a part of general education include…

THE ANGULAR MOMENTUM OF MAGNETIZED MOLECULAR CLOUD CORES: A TWO-DIMENSIONAL-THREE-DIMENSIONAL COMPARISON

International Nuclear Information System (INIS)

Dib, Sami; Csengeri, Timea; Audit, Edouard; Hennebelle, Patrick; Pineda, Jaime E.; Goodman, Alyssa A.; Bontemps, Sylvain

2010-01-01

In this work, we present a detailed study of the rotational properties of magnetized and self-gravitating dense molecular cloud (MC) cores formed in a set of two very high resolution three-dimensional (3D) MC simulations with decaying turbulence. The simulations have been performed using the adaptative mesh refinement code RAMSES with an effective resolution of 4096 3 grid cells. One simulation represents a mildly magnetically supercritical cloud and the other a strongly magnetically supercritical cloud. We identify dense cores at a number of selected epochs in the simulations at two density thresholds which roughly mimic the excitation densities of the NH 3 (J - K) = (1,1) transition and the N 2 H + (1-0) emission line. A noticeable global difference between the two simulations is the core formation efficiency (CFE) of the high-density cores. In the strongly supercritical simulations, the CFE is 33% per unit free-fall time of the cloud (t ff,cl ), whereas in the mildly supercritical simulations this value goes down to ∼6 per unit t ff,cl . A comparison of the intrinsic specific angular momentum (j 3D ) distributions of the cores with the specific angular momentum derived using synthetic two-dimensional (2D) velocity maps of the cores (j 2D ) shows that the synthetic observations tend to overestimate the true value of the specific angular momentum by a factor of ∼8-10. We find that the distribution of the ratio j 3D /j 2D of the cores peaks at around ∼0.1. The origin of this discrepancy lies in the fact that contrary to the intrinsic determination of j which sums up the individual gas parcels' contributions to the angular momentum, the determination of the specific angular momentum using the standard observational procedure which is based on a measurement on the global velocity gradient under the hypothesis of uniform rotation smoothes out the complex fluctuations present in the 3D velocity field. Our results may well provide a natural explanation for the

Bibliographic Resources for the Historian of Astronomy

Science.gov (United States)

Corbin, B. G.

1999-12-01

Many large library collections now have online bibliographic catalogs on the web. These provide many hidden resources for the historian of astronomy. Special searching techniques will allow the historian to scan bibliographic records of hundreds of entries relating to biographies of astronomers, collected works of astronomers, ancient and medieval astronomy and many other historical subjects. Abstract databases such as the Astrophysics Data System and ARIBIB are also adding much historical bibliographic information. ARIBIB will eventually contain scanned images of the Astronomischer Jahresbericht containing bibliographic entries for all literature of astronomy from 1899 to 1968 and Astronomy and Astrophysics Abstracts from 1969 to present. Commercial services such as UnCover and FirstSearch provide a means of reaching bibliographic entries for journal and book literature in the history of astronomy which were not easily located in the past. A broad overview of these collections and services will be given, and searching techniques for finding ``hidden" bibliographic data will be presented. Web page addresses will be given for all sources covered.

Identification and Support of Outstanding Astronomy Students

Science.gov (United States)

Stoev, A. D.; Bozhurova, E. S.

2006-08-01

The aims, organizational plan and syllabus of a specialized Astronomy School with a subject of training students for participation in the International Astronomy Olympiad, are presented. Thematic frame includes basic educational activities during the preparation and self-preparation of the students and their participation in astronomical Olympiads. A model of identification and selection of outstanding students for astronomical Olympiads has been developed. Examples of didactic systems of problems for development of mathematical, physical and astronomical skills are shown. The programme ends with individual training for solving problems on astronomy and astrophysics. Possibilities, which the characteristic, non-standard astronomical problems give for stimulating the creative and original thinking, are specified. Basic psychological condition for development of the students' creative potential - transformation of the cognitive content in emotional one - is demonstrated. The programme of identification and support of outstanding students on astronomy is realized in collaboration with The Ministry of Education and Science, Public Astronomical Observatories and Planetaria, Institute of Astronomy - Bulgarian Academy of Sciences, and The Union of Astronomers in Bulgaria.

The future of astronomy in Australia

Science.gov (United States)

Sadler, Elaine M.

2017-09-01

Australian astronomy has a bright future, thanks largely to recent government investments in major new telescopes, instruments and research centres. There are some short-term challenges as Australia's focus continues to shift from the current (mainly) national facilities for radio and optical astronomy to new multinational and global facilities.

Astronomy Research Seminars

Science.gov (United States)

Genet, Russell M.

2018-06-01

Astronomy Research Seminars are offered by a rapidly growing number of community colleges and universities. Over the past decade some 120 student team research papers have been published with approximately 500 coauthors. Each team manages their own research, obtains and analyzes original data, writes a team paper, obtains an external review, submits their paper for publication, and gives a public PowerPoint presentation. The student teams are supported by: (1) an extensive community-of-practice which consists of professional and amateur astronomers, educators, and Seminar graduates; (2) the Institute for Student Astronomical Research (www.in4star.org); (3) the Small Telescope Astronomy Research Handbook and (4) an in-person/online, open-source Canvas learning management system with videos, quizzes, and other, extensive supporting material. Team research projects are completed in a semester or less and are managed by the students themselves. The Seminars have expanded from double star astronomy to asteroid astrometry, eclipsing binary times of minima, and exoplanet transits. Conducting authentic research inspires students, provides them with important skills in teamwork, project management and scientific literacy, and gives them confidence in their abilities to participate in scientific research. Being coauthors of published papers boosts student educational careers with respect to admissions and scholarships.

Relation of Astronomy to other Sciences, Culture and Society

Science.gov (United States)

Harutyunian, H. A.; Mickaelian, A. M.; Farmanyan, S. V.

2015-07-01

The book contains the Proceedings of XIII Annual Meeting of the Armenian Astronomical Society "Relation of Astronomy to other Sciences, Culture and Society". It consists of 9 main sections: "Introductory", "Astronomy and Philosophy", "Astrobiology", "Space-Earth Connections", "Astrostatistics and Astroinformatics", "Astronomy and Culture, Astrolinguistics", "Archaeoastronomy", "Scientific Tourism and Scientific Journalism", and "Armenian Astronomy". The book may be interesting to astronomers, philosophers, biologists, culturologists, linguists, historians, archaeologists and to other specialists, as well as to students.

Angular Momentum in Dwarf Galaxies

Directory of Open Access Journals (Sweden)

Del Popolo A.

2014-06-01

Full Text Available We study the “angular momentum catastrophe” in the framework of interaction among baryons and dark matter through dynamical friction. By means of Del Popolo (2009 model we simulate 14 galaxies similar to those investigated by van den Bosch, Burkert and Swaters (2001, and calculate the distribution of their spin parameters and the angular momenta. Our model gives the angular momentum distribution which is in agreement with the van den Bosch et al. observations. Our result shows that the “angular momentum catastrophe” can be naturally solved in a model that takes into account the baryonic physics and the exchange of energy and angular momentum between the baryonic clumps and dark matter through dynamical friction.

Radio astronomy on the moon

International Nuclear Information System (INIS)

Burns, J.O.; Asbell, J.

1987-01-01

The advantages and opportunities for radio astronomy on the moon during the early to mid 21st century are reviewed. In particular, it is argued that the lack of atmosphere, the extremely low seismic activity, the low RF background, and the natural cryogenic environment make the moon (particularly the far side and the poles) a nearly ideal locale for submillimeter/FIR to VLF (below 10 MHz) radio astronomy. 22 references

Historic Radio Astronomy Working Group

Science.gov (United States)

2007-06-01

This special issue of Astronomische Nachrichten contains the proceedings of a session of the Historic Radio Astronomy Working Group of the International Astronomical Union that took place during the 26th General Assembly of the IAU in Prague on 17th August 2006. In addition to the talks presented in Prague some contributions were solicited to give a more complete overview of `The Early History of European Radio Astronomy'.

The astronomy education through interactive materials

Science.gov (United States)

de Macedo, Josué Antunes; Voelzke, Marcos Rincon

2014-11-01

This study presents results of a survey conducted at the Federal Institution of Education, Science and Technology in the North of Minas Gerais (IFNMG), and aimed to investigate the potentialities of the use of interactive materials in the teaching of astronomy. An advanced training course with involved learning activities about basic concepts of astronomy was offered to thirty-two Licenciate students in Physics, Mathematics and Biological Sciences, using three pedagogical moments. Among other aspects, the viability of the use of resources was noticed, involving digital technologies and interactive materials on teaching of astronomy, which may contribute to the broadening of methodological options for future teachers and meet their training needs

Some innovative programmes in Astronomy education

Science.gov (United States)

Babu, G. S. D.; Sujatha, S.

In order to inculcate a systematic scientific awareness of the subject of Astronomy among the students and to motivate them to pursue careers in Astronomy and Astrophysics, various innovative educational programmes have been designed at MPBIFR. Among them, the main programme is termed as the ``100-hour Certificate Course in Astronomy and Astrophysics'' which has been designed basically for the students of the undergraduate level of B.Sc. and B.E. streams. The time duration of the 100 hours in this course is partitioned as 36 hours of classroom lectures, 34 hours of practicals and field trips and the remaining 30 hours being dedicated to dissertation writing and seminar presentations by the students. In addition, after the 100-hour course, the students have the option to take up specialized advance courses in the topics of Astrobiology, Astrochemistry, Radio Astronomy, Solar Astronomy and Cosmology as week-end classes. These courses are at the post graduate level and are covered in a span of 18 to 20 hours spread over a period of 9 to 10 weeks. As a preparatory programme, short-term introductory courses in the same subject are conducted for the high school students during the summer vacation period. Along with this, a three-week programme in basic Astronomy is also designed as an educational package for the general public. The students of these courses have the opportunity of being taken on field trips to various astronomical centers as well as the Radio, Solar and the Optical Observatories as part of their curriculum. The guided trips to the ISRO’s Satellite Centre at Bangalore and the Satellite Launching Station at SHAR provide high degree of motivation apart from giving thrilling experiences to the students. Further, the motivated students are encouraged to involve themselves in regular research programmes in Astronomy at MPBIFR for publishing research papers in national and international journals. The teaching and mentoring faculty for all these programmes

Problems facing promotion of astronomy in Arab countries

Science.gov (United States)

Osman, Anas M. I.

Promotion of astronomy in Arab countries is facing many scientific and technical problems. Teaching astronomy starts very late in schools, with very simple and limited courses. Many teachers lack a suitable astronomical background, which can lead to incorrect understanding by students of many astronomical ideas and phenomena. Teaching astronomy at higher levels is also very limited, for example: among the 16 universities in Egypt, astronomy is taught in only two faculties of science, just for two years. Graduate students find many difficulties in obtaining jobs related to astronomical activities and this is a serious limitation on the attraction of the study of astronomy. On the other hand, astronomical institutions are suffering from a serious lack of the new sophisticated equipment, while the budget allotted for maintenance is very small, and there is a serious shortage of technical staff. The training of astronomers and technicians is badly needed, since good research work depends on modern technological equipment and the complicated software used in controlling such equipment and in data analysis. Good libraries are needed for promotion of astronomy especially, the Internet facilities available for the staff is very limited. The effects of culture are very clear; many authorities in developing countries believe that astronomy is a luxury. Finally, most of astronomers are engaged with a lot of administration for all matters, so the free time left for science is very limited.

HF Radio Astronomy from a Small Satellite

Science.gov (United States)

2016-06-15

SSC16-XI-03 HF Radio Astronomy from a Small Satellite Frank C. Robey1, Mary Knapp2, Alan J. Fenn1, Mark Silver1, Kerry Johnson1 Frank J. Lind3...frequency end of the electromagnetic spectrum (below 15 MHz) is one of the least explored windows in observational astronomy . Observations at these...pdf. [Accessed: 17-Oct-2015]. 3. G. Hallinan, “The Owens Valley LWA,” in Exascale Radio Astronomy , 2014, vol. 2. 4. C. J. Lonsdale, R. J. Cappallo

Some Daytime Activities in Solar Astronomy

Science.gov (United States)

Burin, Michael J.

2016-01-01

This century's transits of Venus (2004, 2012) captured significant public attention, reminding us that the wonders of astronomy need not be confined to the night. And while nighttime telescope viewing gatherings (a.k.a. "star parties") are perennially popular, astronomy classes are typically held in the daytime. The logistics of…

Student Comprehension of Mathematics through Astronomy

Science.gov (United States)

Search, Robert

2016-01-01

The purpose of this study is to examine how knowledge of astronomy can enhance college-level learning situations involving mathematics. The fundamental symbiosis between mathematics and astronomy was established early in the 17th century when Johannes Kepler deduced the 3 basic laws of planetary motion. This mutually harmonious relationship…

A Brief History of Publishing Papers on Astronomy Education Research

Science.gov (United States)

Fraknoi, Andrew

2014-01-01

While some research had been done on K-12 and planetarium astronomy teaching from the 1930's to the 1980's, the growth of research on college physics education offered astronomy education researchers a model for examining techniques for teaching introductory college astronomy survey "Astronomy 101" courses as well. This early research…

Teach Astronomy: An Educational Resource for Formal and Informal Learners

Science.gov (United States)

Impey, Chris David

2018-01-01

Teach Astronomy is an educational resource, available in the form of a user-friendly, platform-agnostic website. Ideal for college-level, introductory astronomy courses, Teach Astronomy can be a valuable reference for astronomers at all levels, especially informal learners. Over the past year, multiple changes have been made to the infrastructure behind Teach Astronomy to provide high availability to our tens of thousands of monthly, unique users, as well as fostering in new features. Teach Astronomy contains interactive tools which supplement the free textbook, such as a Quiz Tool with real-time feedback. The site also provides a searchable collection of Chris Impey’s responses to questions frequently asked by our users. The developers and educators behind Teach Astronomy are working to create an environment which encourages astronomy students of all levels to continue to increase their knowledge and help others learn.

The decade of discovery in astronomy and astrophysics

International Nuclear Information System (INIS)

Anon.

1991-01-01

The conference presents papers on recommended ground- and space-based initiatives for the 1990s. The need to restore the research infrastructure at the university level is addressed as well as ways of achieving a balanced space program. Consideration is also given to science opportunities, astronomy and the computer revolution, lunar astronomy, policy opportunities, and astronomy as a national asset

New energy levels of praseodymium with large angular momentum

Energy Technology Data Exchange (ETDEWEB)

Khan, Shamim; Siddiqui, Imran; Gamper, Bettina; Syed, Tanweer Iqbal; Guthoehrlein, Guenter H.; Windholz, Laurentius [Inst. f. Experimentalphysik, Techn. Univ. Graz, Petersgasse 16, A-8010 Graz (Austria)

2011-07-01

The electronic ground state configuration of praseodymium {sup 59}Pr{sub 141} is [Xe] 4f{sup 3}6s{sup 2}, with ground state level {sup 4}I{sub 9/2}. Our research is mainly devoted to find previously unknown energy levels by the investigation of spectral lines and their hyperfine structures. In a hollow cathode discharge lamp praseodymium atoms and ions in ground and excited states are excited to high lying states by laser light. The excitation source is a tunable ring-dye laser system, operated with R6G, Kiton Red, DCM and LD700. A high resolution Fourier transform spectrum is used for selecting promising excitation wavelengths. Then the laser wavelength is tuned to a strong hyperfine component of the spectral line to be investigated, and a search for fluorescence from excited levels is performed. From the observed hyperfine structure we determine J-values and hyperfine constants A of the combining levels. This information, together with excitation and fluorescence wavelengths, allows us to find the energies of involved new levels. Up to now we have discovered large number of previously unknown energy levels with various angular momentum values. We present here the data (energies, parities, angular momenta J, magnetic hyperfine constants A) of ca. 40 new, until now unknown energy levels with high angular momentum values: 15/2, 17/2, 19/2, 21/2.

SOUTHERN MASSIVE STARS AT HIGH ANGULAR RESOLUTION: OBSERVATIONAL CAMPAIGN AND COMPANION DETECTION

Energy Technology Data Exchange (ETDEWEB)

Sana, H. [European Space Agency/Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Le Bouquin, J.-B.; Duvert, G.; Zins, G. [Université Grenoble Alpes, IPAG, F-38000 Grenoble (France); Lacour, S.; Gauchet, L.; Pickel, D. [LESIA, Observatoire de Paris, CNRS, UPMC, Université Paris-Diderot, Paris Sciences et Lettres, 5 Place Jules Janssen, F-92195 Meudon (France); Berger, J.-P. [European Southern Observatory, Schwarzschild-Str. 2, D-85748 Garching bei München (Germany); Norris, B. [Sydney Institute for Astronomy, School of Physics, University of Sydney, NSW 2006 (Australia); Olofsson, J. [Max-Planck-Institut für Astronomie, Koenigstuhl 17, D-69117 Heidelberg (Germany); Absil, O. [Département d' Astrophysique, Géophysique et Océanographie, Université de Liège, 17 Allée du Six Août, B-4000 Liège (Belgium); De Koter, A. [Astrophysical Institute Anton Pannekoek, Universiteit van Amsterdam, Science Park 904, 1098XH Amsterdam (Netherlands); Kratter, K. [JILA, 440 UCB, University of Colorado, Boulder, CO 80309-0440 (United States); Schnurr, O. [Leibniz-Institut für Astrophysik Potsdam, An der Sternwarte 16, D-14482 Potsdam (Germany); Zinnecker, H., E-mail: hsana@stsci.edu [Deutsches SOFIA Instituut, SOFIA Science Center, NASA Ames Research Center, Mail Stop N232-12, Moffett Field, CA 94035 (United States)

2014-11-01

Multiplicity is one of the most fundamental observable properties of massive O-type stars and offers a promising way to discriminate between massive star formation theories. Nevertheless, companions at separations between 1 and 100 milliarcsec (mas) remain mostly unknown due to intrinsic observational limitations. At a typical distance of 2 kpc, this corresponds to projected physical separations of 2-200 AU. The Southern MAssive Stars at High angular resolution survey (SMaSH+) was designed to fill this gap by providing the first systematic interferometric survey of Galactic massive stars. We observed 117 O-type stars with VLTI/PIONIER and 162 O-type stars with NACO/Sparse Aperture Masking (SAM), probing the separation ranges 1-45 and 30-250 mas and brightness contrasts of ΔH < 4 and ΔH < 5, respectively. Taking advantage of NACO's field of view, we further uniformly searched for visual companions in an 8'' radius down to ΔH = 8. This paper describes observations and data analysis, reports the discovery of almost 200 new companions in the separation range from 1 mas to 8'' and presents a catalog of detections, including the first resolved measurements of over a dozen known long-period spectroscopic binaries. Excluding known runaway stars for which no companions are detected, 96 objects in our main sample (δ < 0°; H < 7.5) were observed both with PIONIER and NACO/SAM. The fraction of these stars with at least one resolved companion within 200 mas is 0.53. Accounting for known but unresolved spectroscopic or eclipsing companions, the multiplicity fraction at separation ρ < 8'' increases to f {sub m} = 0.91 ± 0.03. The fraction of luminosity class V stars that have a bound companion reaches 100% at 30 mas while their average number of physically connected companions within 8'' is f {sub c} = 2.2 ± 0.3. This demonstrates that massive stars form nearly exclusively in multiple systems. The nine non-thermal radio

High-Resolution Detector For X-Ray Diffraction

Science.gov (United States)

Carter, Daniel C.; Withrow, William K.; Pusey, Marc L.; Yost, Vaughn H.

1988-01-01

Proposed x-ray-sensitive imaging detector offers superior spatial resolution, counting-rate capacity, and dynamic range. Instrument based on laser-stimulated luminescence and reusable x-ray-sensitive film. Detector scans x-ray film line by line. Extracts latent image in film and simultaneously erases film for reuse. Used primarily for protein crystallography. Principle adapted to imaging detectors for electron microscopy and fluorescence spectroscopy and general use in astronomy, engineering, and medicine.

Astronomy in the streets

Science.gov (United States)

Kebe, Fatoumata

2015-08-01

The Ephemerides Association was founded last year by a PhD student in Astronomy. The association is devoted to the promotion and advancement of knowledge of the universe through research and education.The main activities of the association are scientific meetings, the planning and realization of scientific projects, the support of the scientific activities of its members, and the dissemination of related information among members and other interested persons.The association targets the disadvantaged zones of the Paris suburbs.The main issue was how to bring astronomy in those places. In the suburbs, since most of the youth are poor, most leisure activities like cinema are out of your reach. Thus, mostly of them will play football or basketball outside.We decided to go to meet young people who find themselves together in the evening. We prepare the telescope as well as the fasicules to start the observation of the planets. The discussion finally lead to their career plans and aspirations. Astronomy has become a tool to address societal issues. We present our results after one year of activity.

Angular glint effects generation for false naval target verisimility requirements

International Nuclear Information System (INIS)

Kostis, Theodoros G; Galanis, Konstantinos G; Katsikas, Sokratis K

2009-01-01

A stimulating problem in the generation of coherent countermeasures for high range resolution radar systems is the inclusion of angular glint effects in the preparation of the false target mask. Since angular glint is representative of extended naval targets, this inclusion increases the credibility factor of the decoy playback signal at the adversary radar-operator station. In this paper, the ability of an interferometric inverse synthetic aperture radar (InISAR) simulator to provide a proof of concept towards the clarification of this challenging task is ascertained. The solution consists of three novel vector representations of the generated data, which are proven to behave according to the laws of physics governing the glint phenomenon. The first depiction is the angular glint injection at the target which is followed by the representation of the wavefront distortion at the radar. A value-added time procession integration of the target in pure roll motion provides an expected by ISAR theory side-view image of the naval extended false target. The effectiveness of the proposed approach through verification and validation of the results by using the method of pictorial evidence is established. A final argument is raised on the usage of this software tool for actual obfuscation and deception actions for air defence at sea applications

Data-oriented development with AngularJS

CERN Document Server

Waikar, Manoj

2015-01-01

This book helps beginner-level AngularJS developers organize AngularJS applications by discussing important AngularJS concepts and best practices. If you are an experienced AngularJS developer but haven't written directives or haven't created custom HTML controls before, then this book is ideal for you.

The National Astronomy Consortium (NAC)

Science.gov (United States)

Von Schill, Lyndele; Ivory, Joyce

2017-01-01

The National Astronomy Consortium (NAC) program is designed to increase the number of underrepresented minority students into STEM and STEM careers by providing unique summer research experiences followed by long-term mentoring and cohort support. Hallmarks of the NAC program include: research or internship opportunities at one of the NAC partner sites, a framework to continue research over the academic year, peer and faculty mentoring, monthly virtual hangouts, and much more. NAC students also participate in two professional travel opportunities each year: the annual NAC conference at Howard University and poster presentation at the annual AAS winter meeting following their summer internship.The National Astronomy Consortium (NAC) is a program led by the National Radio Astronomy Consortium (NRAO) and Associated Universities, Inc. (AUI), in partnership with the National Society of Black Physicist (NSBP), along with a number of minority and majority universities.

Astronomy in Primary and Secondary Education in Slovenia

Science.gov (United States)

Gomboc, Andreja

2015-08-01

I will present the status of astronomy in educational system in Slovenia. In primary schools astronomy is offered as an optional course in the last 3 grades (12-15 yrs old), while in secondary schools a few astronomical topics are present only as part of other subjects (e.g. physics, geography). I will describe a pilot project of an astronomy course in secondary schools, which was carried out in the school year 2013/14. The main focus of my presentation will be the experience gained with organisation of the Slovenian National Astronomy Competition. It is organised by the Slovenian Society of Mathematicians, Physicists and Astronomers since 2009, building on an extensive network of over 200 primary and secondary school teachers who participated in IYA2009 activities, and who now represent majority of mentors for the competition. In 2013, only 5 years after the start of competition, our pupils attended the International Olympiad on Astronomy and Astrophysics for the first time and with great success. Supporting activities include the Slovenian version of the Portal to the Universe (www.portalvvesolje.si) and translation of Space Scoop astronomy news for children.

AngularJS web application development

CERN Document Server

Darwin, Peter Bacon

2013-01-01

The book will be a step-by-step guide showing the readers how to build a complete web app with AngularJSJavaScript developers who want to learn AngularJS for developing web apps. Knowledge of JavaScript and HTML is expected. No knowledge of AngularJS is required.

A Website for Astronomy Education and Outreach

Science.gov (United States)

Impey, C.; Danehy, A.

2017-09-01

Teach Astronomy is a free, open access website designed for formal and informal learners of astronomy. The site features: an online textbook complete with quiz questions and a glossary; over ten thousand images; a curated collection of the astronomy articles in Wikipedia; a complete video lecture course; a video Frequently Asked Questions tool; and other materials provided by content partners. Clustering algorithms and an interactive visual interface allow users to browse related content. This article reviews the features of the website and how it can be used.

Astronomy on Tap: science engagement in the pub

Science.gov (United States)

Livermore, Rachael C.; Silverman, Jeffrey Michael

2015-08-01

Astronomy on Tap is a series of free lectures by astronomers in the pub, aimed at disseminating the latest research to the public in an informal setting. Started in New York City in 2013, Astronomy on Tap has now expanded to seven cities across North and South America. Organized by local astronomers, each event features talks by astronomers from local institutions or visitors, or others whose professions or hobbies intersect with astronomy, along with games and opportunities for the public to interact with professional astronomers. The largest Astronomy on Tap events are in Austin, Texas, attracting over 150 people each month, which consists of populations outside of the self-selected groups that might be reached by more formal EPO activities. The organisers of Astronomy on Tap in Austin (AoTATX) will discuss the impact of and feedback from all of the locations, and present information on setting up new satellite locations.

How, precisely, can astronomy be of benefit to anyone?

NARCIS (Netherlands)

Jones, Bernard J. T.; VallsGabaud, D; Boksenberg, A

Astronomy as an observational science is technology driven both from the point of view of data, acquisition and of data processing and visualisation. Astronomy exploits a very wide base of technologies which are developed, enhanced and extended by users. Consequently, astronomy can return new and

Angular momentum of dwarf galaxies

Science.gov (United States)

Kurapati, Sushma; Chengalur, Jayaram N.; Pustilnik, Simon; Kamphuis, Peter

2018-05-01

Mass and specific angular momentum are two fundamental physical parameters of galaxies. We present measurements of the baryonic mass and specific angular momentum of 11 void dwarf galaxies derived from neutral hydrogen (HI) synthesis data. Rotation curves were measured using 3D and 2D tilted ring fitting routines, and the derived curves generally overlap within the error bars, except in the central regions where, as expected, the 3D routines give steeper curves. The specific angular momentum of void dwarfs is found to be high compared to an extrapolation of the trends seen for higher mass bulge-less spirals, but comparable to that of other dwarf irregular galaxies that lie outside of voids. As such, our data show no evidence for a dependence of the specific angular momentum on the large scale environment. Combining our data with the data from the literature, we find a baryonic threshold of ˜109.1 M⊙ for this increase in specific angular momentum. Interestingly, this threshold is very similar to the mass threshold below which the galaxy discs start to become systematically thicker. This provides qualitative support to the suggestion that the thickening of the discs, as well as the increase in specific angular momentum, are both results of a common physical mechanism, such as feedback from star formation. Quantitatively, however, the amount of star formation observed in our dwarfs appears insufficient to produce the observed increase in specific angular momentum. It is hence likely that other processes, such as cold accretion of high angular momentum gas, also play a role in increasing the specific angular momentum.

The history of astronomy a very short introduction

CERN Document Server

Hoskin, Michael

2003-01-01

The History of Astronomy: A Very Short Introduction traces the history of Western astronomy, from prehistoric times to the origins of astrophysics in the mid-nineteenth century and the technical developments since the Second World War. Astronomy, perhaps the first of the sciences, was already well developed by the time of Christ — the arithmetical astronomy of the Babylonians was merged with the Greek geometrical approach. This legacy was transmitted to the West via Islam and led to the Copernican revolution, which in turn led to Kepler and Newton, who provided the principles on which the exploration of the solar system and the stars continued in the eighteenth- and nineteenth centuries.

Infrared Astronomy Satellite

Science.gov (United States)

Ferrera, G. A.

1981-09-01

In 1982, the Infrared Astronomy Satellite (IRAS) will be launched into a 900-km sun-synchronous (twilight) orbit to perform an unbiased, all-sky survey of the far-infrared spectrum from 8 to 120 microns. Observations telemetered to ground stations will be compiled into an IR astronomy catalog. Attention is given the cryogenically cooled, 60-cm Ritchey-Chretien telescope carried by the satellite, whose primary and secondary mirrors are fabricated from beryllium by means of 'Cryo-Null Figuring'. This technique anticipates the mirror distortions that will result from cryogenic cooling of the telescope and introduces dimensional compensations for them during machining and polishing. Consideration is also given to the interferometric characterization of telescope performance and Cryo/Thermal/Vacuum simulated space environment testing.

Astronomically speaking a dictionary of quotations on astronomy and physics

CERN Document Server

Gaither, CC

2003-01-01

To understand the history, accomplishments, failures, and meanings of astronomy requires a knowledge of what has been said about astronomy by philosophers, novelists, playwrights, poets, scientists, and laymen. With this in mind, Astronomically Speaking: A Dictionary of Quotations on Astronomy and Physics serves as a guide to what has been said about astronomy through the ages. Containing approximately 1,550 quotations and numerous illustrations, this resource is the largest compilation of astronomy and astrophysics quotations published to date.Devoted to astronomy and the closely related areas of mathematics and physics, this resource helps form an accurate picture of these interconnected disciplines. It is designed as an aid for general readers with little knowledge of astronomy who are interested in astronomical topics. Students can use the book to increase their understanding of the complexity and richness that exists in scientific disciplines. In addition, experienced scientists will find it as a handy s...

Gravity wave astronomy

International Nuclear Information System (INIS)

Pinheiro, R.

1979-01-01

The properties and production of gravitational radiation are described. The prospects for their detection are considered including the Weber apparatus and gravity-wave telescopes. Possibilities of gravity-wave astronomy are noted

iSTAR: The International STudy on Astronomy Reasoning

Science.gov (United States)

Tatge, Coty B.; Slater, Timothy F.; Slater, Stephanie J.

2015-08-01

This paper reports the first steps taken in the International STudy on Astronomy Reasoning (iSTAR). The iSTAR Project is an attempt to look beyond traditional wisdom and practices in astronomy education, to discover the ways in which cognitive abilities and human culture interact to impact individuals’ understanding of and relationship to astronomy content knowledge. In contrast to many international studies that seek to rank nations by student performance on standardized tests, the iSTAR Project seeks to find ways that culture may unexpectedly enhance performance in astronomy. Using the Test of Astronomy Standards (TOAST) as a reasonable, initial proxy for the content knowledge a well educated person might know in astronomy, the iSTAR team then defined culture as a construct with five components: practices, traditional knowledge, historical and genealogical relationships, place-based knowledge, and language. Given the complexity of this construct, Stage 1 of the project focuses on the cultural component of language, and assumed that prior to the collection of data from students, the process of translating the TOAST could provide valuable expert-based information on the impact of language on astronomy knowledge. As such, the work began with a study of the translation process. For each of the languages used in the testing phase of the iSTAR protocol, a succession of translators and analysts were engaged, including two educated, non-astronomer native speakers, a native speaking astronomer, and a native speaking linguistics expert. Multiple translations were analyzed in order to make relevant meaning of differences in the translations, and provide commentary on the ways in which metaphor, idiom, cultural history are embedded in the language, providing potential advantages in the learning of astronomy. The first test languages were German, Hawaiian, and American Sign Language, and initial findings suggest that each of these languages provide specific advantages

A Pilot Astronomy Outreach Project in Bangladesh

Science.gov (United States)

Bhattacharya, Dipen; Mridha, Shahjahan; Afroz, Maqsuda

2015-08-01

In its strategic planning for the "Astronomy for Development Project," the International Astronomical Union (IAU) has ecognized, among other important missions, the role of astronomy in understanding the far-reaching possibilities for promoting global tolerance and citizenship. Furthermore, astronomy is deemed inspirational for careers in science and technology. The "Pilot Astronomy Outreach Project in Bangladesh"--the first of its kind in the country--aspires to fulfill these missions. As Bangladesh lacks resources to promote astronomy education in universities and schools, the role of disseminating astronomy education to the greater community falls on citizen science organizations. One such group, Anushandhitshu Chokro (AChokro) Science Organization, has been carrying out a successful public outreach program since 1975. Among its documented public events, AChokro organized a total solar eclipse campaign in Bangladesh in 2009, at which 15,000 people were assembled in a single open venue for the eclipse observation. The organization has actively pursued astronomy outreach to dispel public misconceptions about astronomical phenomena and to promote science. AChokro is currently working to build an observatory and Science Outreach Center around a recently-acquired 14-inch Scmidt-Cassegrain telescope and a soon-to-be-acquired new 16-inch reflector, all funded by private donations. The telescopes will be fitted with photometers, spectrometers, and digital and CCD cameras to pursue observations that would include sun spot and solar magnetic fields, planetary surfaces, asteroid search, variable stars and supernovae. The Center will be integrated with schools, colleges, and community groups for regular observation and small-scale research. Special educational and observing sessions for adults will also be organized. Updates on the development of the Center, which is expected to be functioning by the end of 2015, will be shared and feedback invited on the fostering of

Journal of Astrophysics and Astronomy | Indian Academy of Sciences

Indian Academy of Sciences (India)

2016-01-27

Jan 27, 2016 ... Astronomy is a very interesting subject for undergraduate students studying physics. In this paper, we report astronomy education for undergraduate students in the Physics Department of Guangzhou University, and how we are teaching astronomy to the students. Astrophysics has been rapidly developing ...

Journal of Astrophysics and Astronomy | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Journal of Astrophysics and Astronomy. Subhashis Roy. Articles written in Journal of Astrophysics and Astronomy. Volume 37 Issue 4 December 2016 pp 30 Review. Explosive and Radio-Selected Transients: Transient Astronomy with Square Kilometre Array and its Precursors · Poonam Chandra G. C. ...

Students Across Texas Celebrate Astronomy Day

Science.gov (United States)

Preston, S.; Wetzel, M.; Hemenway, M. K.

2010-08-01

Over the past three years, McDonald Observatory has offered special Astronomy Day videoconference programs to students across Texas—the second largest state in the U.S. (Only Alaska is larger). Videoconferencing allows many students and teachers access to our Observatory, which is remotely located 180 miles (290 kilometers) from any major city. McDonald Observatory partners with Connect2Texas to advertise the Astronomy Day event. Connect2Texas provides the electronic bridge between schools and the Observatory. They also provide an online evaluation for teachers to complete. In 2009 the Astronomy Day videoconference celebrated the International Year of Astronomy and the historic observations made by Galileo Galilei. During the videoconference, the classes explore the Moon or Venus by making real-time telescopic observations. Students also receive an introduction to the Observatory, an opportunity to perform an activity relating to Galileo's observations, and an interview with an astronomer. A website provides teachers pre-and post-video conference materials, instructions, and a certificate of completion that can be customized for each student. The website also lists content alignment with state science education standards.

ORGANIZATIONS AND STRATEGIES IN ASTRONOMY VOLUME 7

CERN Document Server

HECK, ANDRÉ

2006-01-01

This book is the seventh volume under the title Organizations and Strategies in Astronomy (OSA). The OSA series covers a large range of fields and themes: in practice, one could say that all aspects of astronomy-related life and environment are considered in the spirit of sharing specific expertise and lessons learned. The chapters of this book are dealing with socio-dynamical aspects of the astronomy (and related space sciences) community: characteristics of organizations, strategies for development, operational techniques, observing practicalities, journal and magazine profiles, public outreach, publication studies, relationships with the media, research communication, series of conferences, evaluation and selection procedures, research indicators, national specificities, contemporary history, and so on. The experts contributing to this volume have done their best to write in a way understandable to readers not necessarily hyperspecialized in astronomy while providing specific detailed information and somet...

Organizations and Strategies in Astronomy Volume 6

CERN Document Server

Heck, André

2006-01-01

This book is the sixth volume under the title Organizations and Strategies in Astronomy (OSA). The OSA series is intended to cover a large range of fields and themes. In practice, one could say that all aspects of astronomy-related life and environment are considered in the spirit of sharing specific expertise and lessons learned. The chapters of this book are dealing with socio-dynamical aspects of the astronomy (and related space sciences) community: characteristics of organizations, strategies for development, legal issues, operational techniques, observing practicalities, educational policies, journal and magazine profiles, public outreach, publication studies, relationships with the media, research communication, evaluation and selection procedures, research indicators, national specificities, contemporary history, and so on. The experts contributing to this volume have done their best to write in a way understandable to readers not necessarily hyperspecialized in astronomy while providing specific detai...

Time-Domain Astronomy with the Fermi GBM

Science.gov (United States)

Hui, C. M.

2017-01-01

The Fermi Gamma-ray Burst Monitor (GBM) is an all-sky monitoring instrument sensitive to energies from 8 keV to 40 MeV. Over the past 8 years of operation, the GBM has detected over 240 gamma-ray bursts per year and provided timely GCN notices with localization to few-degree accuracy for follow-up observations. In addition to GRBs, Galactic transients, solar flares, and terrestrial gamma-ray flashes have also been observed. In recent years we have also been searching the continuous GBM data for electromagnetic counterpart to astrophysical neutrinos and gravitational wave events, as these are believed to be associated with gamma-ray bursts. With continuous data downlink every few hours and a temporal resolution of 2 microseconds, GBM is well suited for observing transients and supporting EM follow-up in the era of multi-messenger astronomy.

Grist: Grid-based Data Mining for Astronomy

Science.gov (United States)

Jacob, J. C.; Katz, D. S.; Miller, C. D.; Walia, H.; Williams, R. D.; Djorgovski, S. G.; Graham, M. J.; Mahabal, A. A.; Babu, G. J.; vanden Berk, D. E.; Nichol, R.

2005-12-01

The Grist project is developing a grid-technology based system as a research environment for astronomy with massive and complex datasets. This knowledge extraction system will consist of a library of distributed grid services controlled by a workflow system, compliant with standards emerging from the grid computing, web services, and virtual observatory communities. This new technology is being used to find high redshift quasars, study peculiar variable objects, search for transients in real time, and fit SDSS QSO spectra to measure black hole masses. Grist services are also a component of the ``hyperatlas'' project to serve high-resolution multi-wavelength imagery over the Internet. In support of these science and outreach objectives, the Grist framework will provide the enabling fabric to tie together distributed grid services in the areas of data access, federation, mining, subsetting, source extraction, image mosaicking, statistics, and visualization.

Grist : grid-based data mining for astronomy

Science.gov (United States)

Jacob, Joseph C.; Katz, Daniel S.; Miller, Craig D.; Walia, Harshpreet; Williams, Roy; Djorgovski, S. George; Graham, Matthew J.; Mahabal, Ashish; Babu, Jogesh; Berk, Daniel E. Vanden;

Introducing AstroGen: the Astronomy Genealogy Project

Science.gov (United States)

Tenn, Joseph S.

2016-12-01

The Astronomy Genealogy Project (AstroGen), a project of the Historical Astronomy Division of the American Astronomical Society (AAS), will soon appear on the AAS website. Ultimately, it will list the world's astronomers with their highest degrees, theses for those who wrote them, academic advisors (supervisors), universities, and links to the astronomers or their obituaries, their theses when online, and more. At present the AstroGen team is working on those who earned doctorates with astronomy-related theses. We show what can be learned already, with just ten countries essentially completed.

Fused silica segments: a possible solution for x-ray telescopes with very high angular resolution like Lynx/XRS

Science.gov (United States)

Salmaso, Bianca; Basso, Stefano; Civitani, Marta; Ghigo, Mauro; Hołyszko, Joanna; Spiga, Daniele; Vecchi, Gabriele; Pareschi, Giovanni

2017-09-01

In order to look beyond Chandra, the Lynx/XRS mission has been proposed in USA and is currently studied by NASA. The optic will have an effective area of 2.5 m2 and an angular resolution of 0.5 arcsec HEW at 1 keV. In order to fulfill these requirements different technologies are considered, with the approaches of both full and segmented shells (that, possibly, can be also combined together). Concerning the production of segmented mirrors, a variety of thin substrates (glass, metal, silicon) are envisaged, that can be produced using both direct polishing or replication methods. Innovative post-fabrication correction methods (such as piezoelectric or magneto-restrictive film actuators on the back surface, differential deposition, ion implantation) are being also considered in order to reach the final tolerances. In this paper we are presenting a technology development based on fused silica (SiO2) segmented substrates, owing the low coefficient of thermal expansion of Fused Silica and its high chemical stability compared to other glasses. Thin SiO2 segmented substrates (typically 2 mm thick) are figured by direct polishing combined with final profile ion figuring correction, while the roughness reduction is reached with pitch tools. For the profile and roughness correction, the segments are glued to a substrate. In this paper we present the current status of this technology.

Radio astronomy

International Nuclear Information System (INIS)

1985-01-01

It is shown how some of the main areas of current CSIRO radioastronomy research are contributing to increasing our knowledge of the universe. The survey includes background astronomy, interstellar gas, the Sun, exploding stars and pulsars, galaxies and quasars. The Australia Telescope and other CSIRO research programs are described

Upsurge of X-ray astronomy 230-

International Nuclear Information System (INIS)

Hudec, D.R.

1978-01-01

Instruments are described used for X-ray astronomy, namely X-ray detectors and X-ray telescopes. Unlike telescopes, the detectors do not comprise X-ray optics. A survey is given of the results obtained in solar and stellar X-ray astronomy and hypotheses are submitted on the origin of X radiation in the interstellar space. (J.B.)

Characteristics of the telescope for high energy gamma-ray astronomy selected for definition studies on the Gamma Ray Observatory

Science.gov (United States)

Hughes, E. B.; Hofstadter, R.; Rolfe, J.; Johansson, A.; Bertsch, D. L.; Cruickshank, W. J.; Ehrmann, C. H.; Fichtel, C. E.; Hartman, R. C.; Kniffen, D. A.

1980-01-01

The high energy gamma-ray telescope selected for definition studies on the Gamma Ray Observatory provides a substantial improvement in observational capability over earlier instruments. It will have about 20 times more sensitivity, cover a much broader energy range, have considerably better energy resolution and provide a significantly improved angular resolution. The design and performance are described.

The Development of Astronomy and Emergence of Astrophysics in Japan

Science.gov (United States)

Nakamura, Tsuko

This chapter overviews the emergence and development phases of modern astronomy and astrophysics in Japan, mainly before WWII. In the beginning of the nineteenth century under the samurai regime of the Tokugawa Shogunate, shogunal astronomers started to learn Western astronomy through a Dutch translation of the book Astronomie by J.J. Lalande. After the Meiji Restoration (1868) the new government founded the University of Tokyo (1877), the first modern university in Japan, in which Tokyo Astronomical Observatory (TAO) also started in 1888. Terao Hisashi, who had gone to Paris to study the modern astronomy, became the first Director of TAO in 1888. The astronomy introduced by Terao into Japan was so-called classical astronomy. Two of Terao's early students made Japan's first internationally recognized achievements in astronomy, the discovery of the Z-term in the polar motion of the Earth by Kimura (Astronomische Nachrichten, 158, 234-240, 1902) and the discovery of asteroid families by Hirayama (Astronomical Journal, 31, 185-188, 1918).

Astronomy for older eyes a guide for aging backyard astronomers

CERN Document Server

Chen, James L

2017-01-01

This book is for the aging amateur astronomy population, including newcomers to astronomy in their retirement and hobbyists who loved peering through a telescope as a child. Whether a novice or an experienced observer, the practice of astronomy differs over the years. This guide will extend the enjoyment of astronomy well into the Golden Years by addressing topics such as eye and overall health issues, recommendations on telescope equipment, and astronomy-related social activities especially suited for seniors. Many Baby-Boomers reaching retirement age are seeking new activities, and amateur astronomy is a perfect fit as a leisure time activity. Established backyard astronomers who began their love of astronomy in their youth , meanwhile, may face many physical and mental challenges in continuing their lifelong hobby as they age beyond their 55th birthdays. That perfect telescope purchased when they were thirty years old now suddenly at sixty years old feels like an immovable object in the living room. The 20...

Teach Astronomy: An Online Resource for General Education and Informal Learning

Science.gov (United States)

Hardegree-Ullman, Kevin; Impey, C.; Patikkal, A.; Srinathan, A.; Collaboration of Astronomy Teaching Scholars CATS

2012-01-01

Teach Astronomy is a website developed for students and informal learners who would like to learn more general astronomy knowledge. This learning tool aggregates content from a myriad of sources, including: an introductory astronomy text book by C. D. Impey and W. K. Hartmann, astronomy related articles on Wikipedia, images from the Astronomy Picture of the Day, two to three minute video clips by C. D. Impey, podcasts from 365 Days of Astronomy, and news from Science Daily. In addition, Teach Astronomy utilizes a novel technology to cluster and display search results called a Wikimap. We present an overview of the website's features and suggestions for making the best use of Teach Astronomy in the classroom or at home. This material is based in part upon work supported by the National Science Foundation under Grant No. 0715517, a CCLI Phase III Grant for the Collaboration of Astronomy Teaching Scholars (CATS). Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation.

Music and Astronomy Under the Stars - 2009 Update

Science.gov (United States)

Lubowich, Donald A.

2010-01-01

Bring telescope to where the people are! Music and Astronomy Under the Stars is a three-year NASA-funded outreach program at parks during and after concerts and family events - a Halloween Spooky Garden Walk. While there have been many outreach activities and telescope observations at city sidewalks and parks, this program targets a completely different audience - music lovers who attend summer concerts held in community parks. These music lovers who may never have visited a science museum, planetarium, or star party are exposed to telescope observations and astronomy information with no additional travel costs. Music and Astronomy Under the Stars increased awareness, engagement, and interest in astronomy at classical, pop, rock, and ethnic music concerts. This program includes solar observing before the concerts, telescope observations including a live image projection system, an astronomical video presentation, and astronomy banners/posters. Approximately 500 - 16,000 people attended each event and 25% to 50% of the people at each event participated in the astronomy program. This program also reached underrepresented and underserved groups (women, minorities, older adults). The target audience is 2,900,000 people, which is larger than combined population of Atlanta, Boston, Denver, Minneapolis, and San Francisco. Although eleven events were planned in 2009, two were canceled due to rain and our largest event, the NY Philharmonic in the Park (attended by 67,000 people in 2008), was cancelled for financial reasons. Our largest event in 2009 was the Tanglewood Music Festival, Lenox MA, attended by 16,000 people where 5000 people participated in astronomy activities. The Amateur Observers' Society of NY assisted with the NY concerts and the Springfield STARS club assisted at Tanglewood. 1500 people looked through telescopes at the Halloween program (6000 saw the posters). In 2009 over 15,000 people participated in these astronomy activities which were attended by

Design of UHECR telescope with 1 arcmin resolution and 50 deg. field of view

CERN Document Server

Sasaki, M; Asaoka, Y

2002-01-01

A new telescope design based on Baker-Nunn optics is proposed for observation of ultra-high-energy cosmic rays (UHECRs). The optical system has an image resolution better than 0.02 deg. within a wide field of view of 50 deg. angular diameter. When combined with a high-quality imaging device, the proposed design enables the directions of UHECRs and high-energy neutrinos to be determined with an accuracy better than 1 arcmin. The outstanding resolution of this telescope allows charge-separated cosmic-rays to be resolved and the source to be determined accurately. This marked improvement in angular resolution will allow the multi-wavelength and 'multi-particle' observations of astronomical objects through collaboration with established astronomical observations.

Bibliometric evaluation of Finnish astronomy

OpenAIRE

Isaksson, Eva

2007-01-01

Finnish astronomy publishing provides us with an interesting data sample. It is small but not too small: approximately one thousand articles have been published in a decade. There are only four astronomy institutes to be compared. An interesting paradox also emerges in the field: while Finnish science assessments usually value highly the impact of scientific publishing, no serious evaluations using real bibliometric data have been made. To remedy this, a comprehensive ten-year database of ref...

High resolution spectroscopy in the microwave and far infrared

Science.gov (United States)

Pickett, Herbert M.

1990-01-01

High resolution rotational spectroscopy has long been central to remote sensing techniques in atmospheric sciences and astronomy. As such, laboratory measurements must supply the required data to make direct interpretation of data for instruments which sense atmospheres using rotational spectra. Spectral measurements in the microwave and far infrared regions are also very powerful tools when combined with infrared measurements for characterizing the rotational structure of vibrational spectra. In the past decade new techniques were developed which have pushed high resolution spectroscopy into the wavelength region between 25 micrometers and 2 mm. Techniques to be described include: (1) harmonic generation of microwave sources, (2) infrared laser difference frequency generation, (3) laser sideband generation, and (4) ultrahigh resolution interferometers.

Astronomie spatiale infrarouge, aujourd’hui et demain = Infrared space astronomy, today and tomorrow

CERN Document Server

Lequeux, J; David, F

2000-01-01

This book brings together the lectures given at the Les Houches summer school "Infrared space astronomy, today and tomorrow". It gives a wide overview of infrared astronomy, a wavelength domain crucial for studies of the solar system, stars at the beginning and end of their lives, interstellar matter and galaxies at all distances. Recent developments in observational techniques have been tremendous. The first contributions give an introduction to the basic physical processes and methods of detection and data processing. They are followed by a series of lectures dealing with the wide variety of astronomical objects that can be seen in the infrared.

History of Astronomy in Portugal: Theories, Institutions and Practices

Science.gov (United States)

Saraiva, Luis

2014-01-01

In Portugal, throughout its history, astronomy was developed in the context of the mathematical sciences. During the times of Portugal's Maritime Discoveries, astronomical navigation was based on spherical trigonometry, and therefore it was the mathematicians who taught astronomy to the pilots. During the 17th century, basic notions of astronomy were taught in mathematical courses in the University and in the main Jesuit colleges. This tradition continued in the 18th century, so it is no wonder that one of the most influent Portuguese astronomers during this period was the mathematician José Monteiro da Rocha. During the 19th century the new centres of science teaching, as the Polytechnic School in Lisbon, or the Polytechnic Academy in Oporto, developed astronomy teaching and research in the context of the mathematics subjects. The inheritors of these 19th century institutions, respectively the Faculties of Sciences of Lisbon and Oporto, upheld this tradition until the final decades of 20th century and continued to consider astronomy as a subject to be taught in their mathematics departments. This Meeting aims at outlining several perspectives on the history of astronomy in Portugal, particularly analysing its ties with mathematical sciences and astronomy applications. The Meeting is organised by the Museum of Science of the University of Lisbon (MCUL) with CMAF, CMUC, CMUP and the CIUHCT, and is included in CIM events. It is integrated in the commemorations of the International Year of Astronomy (IYA2009).

Introduction to solar radio astronomy and radio physics

International Nuclear Information System (INIS)

Krueger, A.

1979-01-01

A systematic summary is presented of the work done during the last thirty years in the field of solar radio astronomy from the standpoint of general solar physics. Instrumental aspects, observations and theory are covered. A brief introduction is given to the matter consisting of the history of solar radio astronomy and some fundamentals of astronomy and solar physics are outlined. Some topics of the instrumental background of solar radio astronomy and the main results of observations are presented. The elements of a theoretical interpretation of solar radio observations are reported and a synthesis of both observation and theory contributing to a general picture of solar and solar-terrestrial physics is outlined. (C.F./Auth)

To See the Unseen: A History of Planetary Radar Astronomy

Science.gov (United States)

Butrica, Andrew J.

1996-01-01

This book relates the history of planetary radar astronomy from its origins in radar to the present day and secondarily to bring to light that history as a case of 'Big Equipment but not Big Science'. Chapter One sketches the emergence of radar astronomy as an ongoing scientific activity at Jodrell Bank, where radar research revealed that meteors were part of the solar system. The chief Big Science driving early radar astronomy experiments was ionospheric research. Chapter Two links the Cold War and the Space Race to the first radar experiments attempted on planetary targets, while recounting the initial achievements of planetary radar, namely, the refinement of the astronomical unit and the rotational rate and direction of Venus. Chapter Three discusses early attempts to organize radar astronomy and the efforts at MIT's Lincoln Laboratory, in conjunction with Harvard radio astronomers, to acquire antenna time unfettered by military priorities. Here, the chief Big Science influencing the development of planetary radar astronomy was radio astronomy. Chapter Four spotlights the evolution of planetary radar astronomy at the Jet Propulsion Laboratory, a NASA facility, at Cornell University's Arecibo Observatory, and at Jodrell Bank. A congeries of funding from the military, the National Science Foundation, and finally NASA marked that evolution, which culminated in planetary radar astronomy finding a single Big Science patron, NASA. Chapter Five analyzes planetary radar astronomy as a science using the theoretical framework provided by philosopher of science Thomas Kuhn. Chapter Six explores the shift in planetary radar astronomy beginning in the 1970s that resulted from its financial and institutional relationship with NASA Big Science. Chapter Seven addresses the Magellan mission and its relation to the evolution of planetary radar astronomy from a ground-based to a space-based activity. Chapters Eight and Nine discuss the research carried out at ground

A proposed measurement of optical orbital and spin angular momentum and its implications for photon angular momentum

Directory of Open Access Journals (Sweden)

Elliot Leader

2018-04-01

Full Text Available The expression for the total angular momentum carried by a laser optical vortex beam, splits, in the paraxial approximation, into two terms which seem to represent orbital and spin angular momentum respectively. There are, however, two very different competing versions of the formula for the spin angular momentum, one based on the use of the Poynting vector, as in classical electrodynamics, the other related to the canonical expression for the angular momentum which occurs in Quantum Electrodynamics. I analyze the possibility that a sufficiently sensitive optical measurement could decide which of these corresponds to the actual physical angular momentum carried by the beam. Keywords: Photon, Angular momentum, Laser optics, Particle physics

AngularJS : yksisivuisen web-sovelluksen käyttöliittymän toteutus AngularJS:llä

OpenAIRE

Suomijoki, Juha

2015-01-01

Opinnäytetyössä tutkittiin mikä on AngularJS-JavaScript-ohjelmistokehys ja miten se soveltuu yksisivuisen web-sovelluksen käyttöliittymän toteutukseen. AngularJS on vuonna 2012 julkaistu Googlen ylläpitämä JavaScript-ohjelmistokehys, joka on tarkoitettu ensisijaisesti yksisivuisten web-sovellusten kehittämiseen. Opinnäytetyön teoriaosuudessa tutkittiin mikä AngularJS on ja mitkä ovat AngularJS:n keskeiset konseptit ja sovelluskomponentit. Tarkastelu pohjautui AngularJS:stä kirjoitettu...

Quark Orbital Angular Momentum

Directory of Open Access Journals (Sweden)

Burkardt Matthias

2015-01-01

Full Text Available Definitions of orbital angular momentum based on Wigner distributions are used as a framework to discuss the connection between the Ji definition of the quark orbital angular momentum and that of Jaffe and Manohar. We find that the difference between these two definitions can be interpreted as the change in the quark orbital angular momentum as it leaves the target in a DIS experiment. The mechanism responsible for that change is similar to the mechanism that causes transverse single-spin asymmetries in semi-inclusive deep-inelastic scattering.

Motivational Differences between MOOC and Undergraduate Astronomy Students

Science.gov (United States)

Formanek, Martin; Wenger, Matthew; Buxner, Sanlyn; Impey, Chris David

2018-01-01

It is vital for the instructors and designers of the Massive Open Online Courses (MOOCs) to understand the motivation of its users for enrolling in the class and their reasons to engage with the material. This is particularly important for MOOCs focusing on scientific topics such as our MOOC on Astronomy (Astronomy: Exploring time and space) whose audience is less motivated by a desire to advance their careers compared to other MOOCs. In order to learn more about the motivation of our learners we deployed in our Astronomy MOOC a survey based on the Science Motivation Questionnaire II developed by Glynn et. al (2011). We specifically asked for reasons to sign up for the course and the overall motivation and attitude towards astronomy and science courses. We compare results of 3360 participants of this survey with a similar instrument administered to 638 students in undergraduate Astronomy classes for non Astronomy majors at the University of Arizona. Our comparison not only looks at the demographic differences, but also at reasons for signing up for the course and scores in motivational categories such as self-determination, self-efficacy, grade motivation, career motivation, hobby motivation, social motivation, and intrinsic motivation showing, that these populations of learners are fundamentally different.

The astronomy spacelab payloads study: executive volume. Interim report

International Nuclear Information System (INIS)

1975-07-01

The progress of the Astronomy Spacelab Payloads Project at the Goddard Space Flight Center is reported. Astronomical research in space, using the Spacelab in conjunction with the Space Shuttle, is described. The various fields of solar astronomy or solar physics, ultraviolet and optical astronomy, and high energy astrophysics are among the topics discussed. These fields include scientific studies of the Sun and its dynamical processes, of the stars in wavelength regions not accessible to ground based observations, and the exciting new fields of X-ray, gamma ray, and particle astronomy

Selected topics on data analysis in astronomy

International Nuclear Information System (INIS)

Scarsi, L.

1987-01-01

The contents of this book are: General Lectures Given at the Erice II Workshop on Data Analysis in Astronomy: Fundamentals in Data Analysis in Astronomy; Computational Techniques; Evolution of Architectures for Data Processing; Hardware for Graphics and Image Display; and Data Analysis Systems

Ten Years of "Latin-American Journal of Astronomy Education" RELEA: Achievements and Challenges for International Astronomy Education Development

Science.gov (United States)

Bretones, Paulo S.; Jafelice, Luiz C.; Horvath, Jorge E.

2016-01-01

This study reviews 10 years of "Latin-American Journal of Astronomy Education" (RELEA), showing that the journal has become a valuable resource for publishing and highlights its pathway as scholarly journal. Furthermore, it is also a call to astronomy education specialists to consolidate their efforts considering similar journals…

47 CFR 5.91 - Notification of the National Radio Astronomy Observatory.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 1 2010-10-01 2010-10-01 false Notification of the National Radio Astronomy... Astronomy Observatory. In order to minimize possible harmful interference at the National Radio Astronomy... Astronomy Observatory, P.O. Box NZ2, Green Bank, West Virginia, 24944, in writing, of the technical...

Rotations and angular momentum

International Nuclear Information System (INIS)

Nyborg, P.; Froyland, J.

1979-01-01

This paper is devoted to the analysis of rotational invariance and the properties of angular momentum in quantum mechanics. In particular, the problem of addition of angular momenta is treated in detail, and tables of Clebsch-Gordan coefficients are included

The Advanced Gamma-ray Imaging System (AGIS): Focal Plane Detectors

Science.gov (United States)

Mukherjee, Reshmi; Byrum, K.; Drake, G.; Falcone, A.; Funk, S.; Horan, D.; Tajima, H.; Wagner, B.; Williams, D.

2008-04-01

Report of the Focal Plane Instrumentation Working Group, AGIS collaboration: The Advanced Gamma-ray Imaging System (AGIS) is a concept for the next generation instrument in ground-based very high energy gamma-ray astronomy. It has the goal of achieving significant improvement in sensitivity over current experiments. One of the main requirements for AGIS will be to achieve higher angular resolution than current imaging atmospheric Cherenkov telescopes (IACTs). Simulations show that a substantial improvement in angular resolution may be achieved if the pixel size is reduced to 0.05 deg, below that of current IACTs. Reducing the cost per channel and improving reliability and modularity are other important considerations. Here we present several alternatives being considered for AGIS, including both silicon photomultipliers (SiPMs) and multi-anode photomultipliers (MAPMTs) and summarize results from feasibility testing by various AGIS photodetector group members.

Improving Teach Astronomy: A Survey of Instructors

Science.gov (United States)

Wenger, Matthew; Riabokin, Malanka; Impey, Chris David

2018-01-01

Teach Astronomy is a website that provides educational resources for introductory astronomy. The motivation behind constructing this site was to provide quality online educational tools for use as a primary or supplementary instructional resource for teachers and students. The website provides an online textbook, glossary, podcasts and video summaries of concepts. As the popularity of online courses steadily increases, so does the demand for robust online educational resources. In order to cater to our users, our team conducted a survey of the instructors that use Teach Astronomy site for feedback for use in updating and streamlining the website content. The survey collected feedback regarding functionality of each of the website tools, in which courses the site was being used, and the motivation of the instructors use of our site. The overwhelming majority of responses indicate that instructors use the website as a class textbook in introductory astronomy courses for non-science majors, and instructors also generally tended to agree that the site content was comprehensive and lucid. One interesting result of the survey is to cluster topics in a way that is consistent with different levels of instruction (i.e. grouping middle-school level content and university level content distinctly). Our team will use this feedback to improve the Teach Astronomy website and maintain it as a high-quality, free online resource. We will also continue to gather feedback from instructors to ensure that the Teach Astronomy website stays current and remains a valuable online resource for instructors around the country.

Astronomy on a Landfill

Science.gov (United States)

Venner, Laura

2008-09-01

Engaging "K-to-Gray” audiences (children, families, and older adults) in astronomical activities is one of the main goals of the NJMC Center for Environmental and Scientific Education and the William D. McDowell Observatory located in Lyndhurst, NJ. Perched atop a closed and reclaimed municipal solid waste landfill, our new LEED - certified building (certification pending) and William D. McDowell observatory will assist in bringing the goals of IYA 2009 to the approximately 25,000 students and 15,000 adults that visit our site from the NY/NJ region each year. Diversifying our traditional environmental science offerings, we have incorporated astronomy into our repertoire with "The Sun Through Time” module, which includes storytelling, cultural astronomy, telescope anatomy, and other activities that are based on the electromagnetic spectrum and our current knowledge of the sun. These lessons have also been modified to bring astronomy to underserved communities, specifically those individuals that have dexterity or cognitive ability differences. The program is conducted in a classroom setting and is designed to meet New Jersey Core Curriculum Content Standards. With the installation of our new 20” telescope, students and amateur astronomers will be given the opportunity to perform rudimentary research. In addition, a program is in development that will allow individuals to measure local sky brightness and understand the effects of light pollution on astronomical viewing. Teaching astronomy in an urban setting presents many challenges. All individuals, regardless of ability level or location, should be given the opportunity to be exposed to the wonders of the universe and the MEC/CESE has been successful in providing those opportunities.

The Development and Validation of the Test Of Astronomy STandards (TOAST)

Science.gov (United States)

Slater, Stephanie J.

2014-01-01

The Test Of Astronomy STandards (TOAST) is a comprehensive assessment instrument designed to measure students' general astronomy content knowledge. Built upon the research embedded within a generation of astronomy assessments designed to measure single concepts, the TOAST is appropriate to measure across an entire astronomy course. The TOAST's…

Grote Reber, Radio Astronomy Pioneer, Dies

Science.gov (United States)

2002-12-01

Grote Reber, one of the earliest pioneers of radio astronomy, died in Tasmania on December 20, just two days shy of his 91st birthday. Reber was the first person to build a radio telescope dedicated to astronomy, opening up a whole new "window" on the Universe that eventually produced such landmark discoveries as quasars, pulsars and the remnant "afterglow" of the Big Bang. His self- financed experiments laid the foundation for today's advanced radio-astronomy facilities. Grote Reber Grote Reber NRAO/AUI photo "Radio astronomy has changed profoundly our understanding of the Universe and has earned the Nobel Prize for several major contributions. All radio astronomers who have followed him owe Grote Reber a deep debt for his pioneering work," said Dr. Fred Lo, director of the National Radio Astronomy Observatory (NRAO). "Reber was the first to systematically study the sky by observing something other than visible light. This gave astronomy a whole new view of the Universe. The continuing importance of new ways of looking at the Universe is emphasized by this year's Nobel Prizes in physics, which recognized scientists who pioneered X-ray and neutrino observations," Lo added. Reber was a radio engineer and avid amateur "ham" radio operator in Wheaton, Illinois, in the 1930s when he read about Karl Jansky's 1932 discovery of natural radio emissions coming from outer space. As an amateur operator, Reber had won awards and communicated with other amateurs around the world, and later wrote that he had concluded "there were no more worlds to conquer" in radio. Learning of Jansky's discovery gave Reber a whole new challenge that he attacked with vigor. Analyzing the problem as an engineer, Reber concluded that what he needed was a parabolic-dish antenna, something quite uncommon in the 1930s. In 1937, using his own funds, he constructed a 31.4-foot-diameter dish antenna in his back yard. The strange contraption attracted curious attention from his neighbors and became

Marriage of x-ray and optical astronomy

International Nuclear Information System (INIS)

McClintock, J.E.

1975-01-01

An historical discussion of the relation of x-ray and optical astronomy is given including distances within our galaxy, the optical identification of x-ray sources, the binary x-ray stars, neutron stars and black holes, a program in x-ray astronomy, and future missions

Astronomy Enrollments and Degrees: Results from the 2009 & 2010 Surveys of Physics & Astronomy Enrollments and Degrees. Focus On

Science.gov (United States)

Nicholson, Starr; Mulvey, Patrick

2011-01-01

The Statistical Research Center of the American Institute of Physics conducts an annual census from October through February of all departments that offer degrees in astronomy (78) in the United States. Astronomy departments consist of stand-alone degree-granting departments (39) and departments that are administered along with a physics program…

An Interferometric Study of the Post-AGB Binary 89 Herculis. 1: Spatially Resolving the Continuum Circumstellar Environment at Optical and Near-IR Wavelengths with the VLTI, NPOI, IOTA, PTI, and the CHARA Array

Science.gov (United States)

2013-01-01

Herculis I. Spatially resolving the continuum circumstellar environment at optical and near-IR wavelengths with the VLTI, NPOI, IOTA , PTI, and the CHARA...public release; distribution unlimited 13. SUPPLEMENTARY NOTES A&A 559, A111 (2013) 14. ABSTRACT 15. SUBJECT TERMS 16. SECURITY CLASSIFICATION...Array ( IOTA ) and the Center for High Angular Resolution Astronomy (CHARA) Array, covering 0.5 to 2.2 μm and with baselines from 15 to 278 m. Here we

Astronomy and Poetry (overview)

Science.gov (United States)

Samvelyan, David

2016-12-01

Through this work we have tried to show how astronomy penetrates into the poetry of different periods in time and in various poets' works all over the world. The following work has significant cognitive value, demonstrates and reveals the general nature of certain poets' astronomical ideas and provides a brief analysis in some cases. As a result, we have come to the conclusion that astronomy with all its components such as the sky, our solar system and phenomena such as these have always been a source of inspiration for those who create works of art, moreover some of them have even gained actual astronomical knowledge.

Astronomy 3.0 Style

Science.gov (United States)

Accomazzi, A.

2010-10-01

Over the next decade, we will witness the development of a new infrastructure in support of data-intensive scientific research, which includes Astronomy. This new networked environment will offer both challenges and opportunities to our community and has the potential to transform the way data are described, curated and preserved. Based on the lessons learned during the development and management of the ADS, a case is made for adopting the emerging technologies and practices of the Semantic Web to support the way Astronomy research will be conducted. Examples of how small, incremental steps can, in the aggregate, make a significant difference in the provision and repurposing of astronomical data are provided.

Astronomy from Olbers to Schwarzschild. (German Title: Astronomie von Olbers bis Schwarzschild)

Science.gov (United States)

Dick, Wolfgang R.; Hamel, Jürgen

This issue comprises talks presented 2000 September 18 at the colloquium ``International relations in astronomy'' it is supplemented by additional articles about this topic. The foundation of the international ``Vereinigte Astronomische Gesellschaft'', which took place in 1800 in Bremen, prompted us to investigate the development of astronomy in German-speaking regions, and its international relations during the 19th century. We investigate the activities of famous astronomers like W. Olbers, J.E. Bode, F.X. von Zach, J.H. Schroeter, H.C. Schumacher and K. Schwarzschild, as well as those of their less famous professional colleagues like J.G. Schrader and L. de Ball. The geographical spectrum extends from Bremen and Lilienthal over Kiel, Gotha and Dresden to Copenhagen, Vienna and Chile. Among the topics are: telescope construction, including telescopes made by Herschel, the rediscovery of the minor planet Ceres 1801/02, the Berlin ``Astronomisches Jahrbuch'', the foundation of the ``Astronomische Nachrichten'', the evolution from the ``Vereinigte Astronomische Gesellschaft'' to the present-day ``Astronomische Gesellschaft'', the research at the Kuffner Observatory in Vienna, the professionalization in astronomy, and the attempts of many countries to establish a southern observatory in Chile. A listing of astronomical monuments in Lilienthal and Bremen concludes the book. All papers are written in German with English abstracts.

Astronomy and astrophysics for the 1970's. Volume 2. Reports of the panels

International Nuclear Information System (INIS)

1973-01-01

Specific panel reports include: radio astronomy, optical astronomy, infrared astronomy, space astronomy, solar astronomy, theoretical astrophysics, dynamical astronomy, astrophysics and relativity, and statistics. These provide guidance as to the major trends anticipated in astronomical and astrophysical research. They also list instrumental facilities, auxiliary equipment, and programs of theoretical research and offer numerous recommendations

A multiwire proportional chamber for precision studies of neutron β decay angular correlations

International Nuclear Information System (INIS)

Ito, T.M.; Carr, R.; Filippone, B.W.; Martin, J.W.; Plaster, B.; Rybka, G.; Yuan, J.

2007-01-01

A new multiwire proportional chamber (MWPC) was designed and constructed for precision studies of neutron β decay angular correlations. Its design has several novel features, including the use of low pressure neopentane as the MWPC gas and an entrance window made of thin Mylar sheet reinforced with Kevlar fibers. In the initial off-line performance tests, the gas gain of neopentane and the position resolution were studied

2004 ASTRONOMY & ASTROPHYSICS

Indian Academy of Sciences (India)

user

This publication of the Academy on Astronomy and Astrophysics is unique in ... bring out position papers on societal issues where science plays a major ..... funding agencies, the Astronomical Society of ..... orbit very close to the parent star.

Participant Perspectives on the ESO Astronomy Camp Programme

Science.gov (United States)

Olivotto, C.; Cenadelli, D.; Gamal, M.; Grossmann, D.; Teller, L. A. I.; Marta, A. S.; Matoni, C. L.; Taillard, A.

2015-09-01

This article describes the experience of attending the European Southern Observatory (ESO) Astronomy Camp from the perspective of its participants - students aged between 16 and 18 years old from around the world. The students shared a week together during the winter of 2014 in the Alpine village of Saint-Barthelemy, Italy. The camp was organised by ESO in collaboration with Sterrenlab and the Astronomical Observatory of the Autonomous Region of the Aosta Valley and offered a rich programme of astronomy and leisure activities. This article focuses on the concept of astronomy camps, and their role as a unique tool to complement formal classroom education, rather than on the astronomy activities and the scientific programme. Thus, it is not an academic review of the implemented methodologies, but rather a reflection on the overall experience. The article was brought together from collaborative accounts by some of the participants who were asked to reflect on the experience. The participants who contributed to this article represent the diversity of the ESO Astronomy Camp's alumni community.

Radio Astronomy at TIFR, some highlights and reminiscences

Science.gov (United States)

Swarup, G.

Radio astronomy research was initiated at TIFR fifty years ago. In this historical article, I firstly trace my initiation in the field of radio astronomy during 1953-55 in the Radio Physics Laboratory of CSIRO in Australia and later during 1956-63 in USA. In September 1961, four radio astronomers working abroad wrote to a number of scientific organizations in India with their desire to start radio astronomy research in India. Soon thereafter Dr. Homi Bhabha, the founder Director of TIFR, approved the formation of a radio astronomy group therein. I joined TIFR in April 1963. During the last 50 years, TIFR has built two of the world's largest radio telescopes, namely the 530m long and 30 m wide parabolic cylinder equatorially mounted on a hill at Ooty in South India during 1960s and the Giant Metrewave Radio Telescope near Pune, consisting of 30 nos. of fully steerable parabolic dishes of 45 m diameters during 1990s. Fifty years of radio astronomy research at TIFR is briefly highlighted here.

A proposed measurement of optical orbital and spin angular momentum and its implications for photon angular momentum

Science.gov (United States)

Leader, Elliot

2018-04-01

The expression for the total angular momentum carried by a laser optical vortex beam, splits, in the paraxial approximation, into two terms which seem to represent orbital and spin angular momentum respectively. There are, however, two very different competing versions of the formula for the spin angular momentum, one based on the use of the Poynting vector, as in classical electrodynamics, the other related to the canonical expression for the angular momentum which occurs in Quantum Electrodynamics. I analyze the possibility that a sufficiently sensitive optical measurement could decide which of these corresponds to the actual physical angular momentum carried by the beam.

The Eternal Role of Astronomy in History and Civilization

Science.gov (United States)

Theodossiou, E.; Manimanis, V. N.

2010-07-01

Astronomy is the most ancient of all natural sciences. From its roots in ancient Babylonian and Egyptian stellar observations, and through its formulation into a science from the Greek natural philosophers, it defined the measurement of time. The stellar eras and the applications of Astronomy were incorporated in temples, paintings, sculptures and in art in general. Today, the value of Astronomy on practical matters, timekeeping or the navigation, has diminished. However, the eternal questions connected with Astronomy remain: Who are we and where did we come from? How and why was the Universe born? The greatest step to answer this kind of questions came with the so-called Copernican revolution, mostly in the 17th Century. The progress of Astronomy in the 400 years since then answered questions and gave an end to all kinds of superstitions, one more contribution to human civilization.

Resolution of the neutron transport equation by massively parallel computer in the Cronos code

International Nuclear Information System (INIS)

Zardini, D.M.

1996-01-01

The feasibility of neutron transport problems parallel resolution by CRONOS code's SN module is here studied. In this report we give the first data about the parallel resolution by angular variable decomposition of the transport equation. Problems about parallel resolution by spatial variable decomposition and memory stage limits are also explained here. (author)

Vistas in astronomy. Volume 16

International Nuclear Information System (INIS)

Beer, A.

1974-01-01

A series of papers dealing with theoretical and experimental work in solar, planetary, and stellar astronomy, including stellar spectroscopy, photometry, and radio astronomy. The topics covered include: solar flares, the historical development of solar theories, the intrinsic light variation and the reflection effect in very close eclipsing binary systems with distorted components, spectroscopic binaries, early-type stars with abnormal spectra, photometric classification of the O-B stars, the nova DQ Herculis, emission nebulas at radio wavelengths, and the planetary nebulas as radio sources. (IAA)

Practical astronomy with your calculator

CERN Document Server

Duffett-Smith, Peter

1989-01-01

Practical Astronomy with your Calculator, first published in 1979, has enjoyed immense success. The author's clear and easy to follow routines enable you to solve a variety of practical and recreational problems in astronomy using a scientific calculator. Mathematical complexity is kept firmly in the background, leaving just the elements necessary for swiftly making calculations. The major topics are: time, coordinate systems, the Sun, the planetary system, binary stars, the Moon, and eclipses. In the third edition there are entirely new sections on generalised coordinate transformations, nutr

Women's and men's career choices in astronomy and astrophysics

Science.gov (United States)

Ivie, Rachel

2017-01-01

In order to understand gender differences in persistence and attrition from astronomy and physics, the Longitudinal Study of Astronomy Graduate Students follows a cohort of people who were graduate students in astronomy or astrophysics during 2006-07. The first survey was conducted during 2007-08 and the second during 2012-13, when many of the respondents had left graduate school and were working. For respondents who had completed PhDs and were not postdocs, we tested the effects of four major concepts on attrition from physics and astronomy. These concepts included: the imposter syndrome, mentoring and advising during graduate school, work-family balance, and being female. We hypothesized that women would be more likely than men to work outside of astronomy and physics. However, results from the study show that there is no direct independent effect of being female on attrition. Rather, women are more likely to leave astronomy because they are more likely than men to (1) experience difficulties related to the need to find a job for a spouse or partner in the same geographical area, and (2) report less than satisfactory advising during graduate school. This research identifies specific areas of concern that can be addressed by the scientific community to increase the retention of all people, but especially women, in astronomy, physics, and related fields. Funded by National Science Foundation AST-1347723.

Development and Test of a Contactless Position and Angular Sensor Device for the Application in Synchronous Micro Motors

Directory of Open Access Journals (Sweden)

Andreas WALDSCHIK

2009-09-01

Full Text Available In this work, we present a contactless micro position and angular sensor system which consists of fixed commercial magnetic sensor elements, such as hall sensors and a movable part with integrated micro structured polymer magnets. This system serves particularly for linear and rotatory synchronous micro motors which we have developed and successfully tested. In order to achieve high precision and control of these motors an integration of the special micro position and angular sensors is pursued to increase the resolution and accuracy of the devices.

Elementary astronomy

Science.gov (United States)

Fierro, J.

2006-08-01

In developing nations such as Mexico, basic science education has scarcely improved. There are multiple reasons for this problem; they include poor teacher training and curricula that are not challenging for students. I shall suggest ways in which astronomy can be used to improve basic education, it is so attractive that it can be employed to teach how to read and write, learn a second language, mathematics, physics, as well as geography. If third world nations do not teach science in an adequate way, they will be in serious problems when they will try to achieve a better standard of living for their population. I shall also address informal education, it is by this means that most adults learn and keep up to date with subjects that are not their specialty. If we provide good outreach programs in developing nations we can aid adult training; astronomy is ideal since it is particularly multidisciplinary. In particular radio and television programs are useful for popularization since they reach such wide audiences.

The Astronomy Workshop

Science.gov (United States)

Hamilton, D. P.

2005-05-01

The Astronomy Workshop (http://janus.astro.umd.edu) is a collection of interactive online educational tools developed for use by students, educators, and the general public. The more than 20 tools in the Astronomy Workshop are rated for ease-of-use, and have been extensively tested in large university survey courses, classes for undergraduate majors, and High Schools. Here we briefly describe a few of the more popular tools. The Life of the Sun (New!): The history of the Sun is animated as a movie, showing students how the size and color of our star has evolved and will evolve in time. Animated Orbits of Planets and Moons: The orbital motions of planets, moons, asteroids, and comets are animated at their correct relative speeds in accurate to-scale drawings. Solar System Collisions: This most popular of our applications shows what happens when an asteroid or comet with user-defined size and speed impacts a given planet. The program calculates many effects, including the country of impact (if Earth is the target), energy of explosion, crater size, and magnitude of the ``planetquake'' generated. It also displays a relevant image (e.g. terrestrial crater, lunar crater, etc.). Astronomical Distances: Travel away from the Earth at a chosen speed and see how long it takes to reach other planets, stars and galaxies. This tool helps students visualize astronomical distances in an intuitive way. Funding for the Astronomy Workshop is provided by a NASA EPO grant.

Kinematics and resolution at future ep colliders

International Nuclear Information System (INIS)

Bluemlein, J.; Klein, M.

1992-01-01

Limitations due to resolution and kinematics are discussed of the (Q 2 , x) range accessible with electron-proton colliders after HERA. For the time after HERA one may think of two electron-proton colliders: an asymmetric energy machine and a rather symmetric one. Both colliders are compared here in order to study the influence of the different E l /E p ratios on the accessible kinematic range which is restricted due to angular coverage, finite detector resolution and calibration uncertainties

Preservice Science Teachers' Beliefs about Astronomy Concepts

Science.gov (United States)

Ozkan, Gulbin; Akcay, Hakan

2016-01-01

The purpose of this study was to investigate preservice science teachers' conceptual understanding of astronomy concepts. Qualitative research methods were used. The sample consists of 118 preservice science teachers (40 freshmen, 31 sophomores, and 47 juniors). The data were collected with Astronomy Conceptual Questionnaire (ACQ) that includes 13…

A Partnership in Observational and Computational Astronomy (POCA)

Science.gov (United States)

Walter, Donald K.; Brittain, S. D.; Cash, J. L.; Hartmann, D. H.; Howell, S. B.; King, J. R.; Leising, M. D.; Mayo, E. A.; Mighell, K. J.; Smith, D. M., Jr.

2009-01-01

A partnership has been established between South Carolina State University (SCSU, a Historically Black College/University), the National Optical Astronomy Observatory (NOAO) and Clemson University (CU) under an award from NSF's "Partnerships in Astronomy and Astrophysics Research and Education (PAARE)" program. The mission of POCA is to develop an effective, long-term partnership that combines the strengths of the three institutions to increase the scientific and educational output of all the partners with special emphasis on enhancing diversity in the field of astronomy. Components of the program include enhancing faculty and student research in astronomy at SCSU, recruiting and retaining underrepresented minority students into the field, outreach through planetarium programs and museum exhibits and developing web based resources in astronomy education. Activities in the first year of the program are discussed. We have begun developing and testing several new astronomy laboratory exercises. Our first summer internship program has concluded successfully. With PAARE scholarship money, we are now supporting four physics majors at SCSU who have chosen the astronomy option (concentration) for their degree. SCSU undergraduates have acquired observing experience on the KPNO Mayall 4-meter telescope under the guidance of faculty and graduate students from CU. NOAO astronomers have collaborated with SCSU faculty to begin a research program that studies RV Tauri stars. Funds from PAARE are supporting follow-up research to a just-completed doctoral dissertation by E. A. Mayo described elsewhere in these proceedings. Future plans for graduate fellowships and related activities are discussed in addition to summer internships for POCA undergraduates at CU and NOAO. Support for this work was provided by the NSF PAARE program to South Carolina State University under award AST-0750814.

Astronomy Outreach for Large, Unique, and Unusual Audiences

Science.gov (United States)

Lubowich, Donald

2015-08-01

My successful outreach program venues include: outdoor concerts and festivals; the US National Mall; churches, synagogues, seminaries, or clergy conferences; the Ronald McDonald Houses of Long Island and Chicago; the Winthrop U. Hospital Children’s Medical Center the Fresh Air Fund summer camps (low-income and special needs); a Halloween star party (costumed kids look through telescopes); a Super Bowl Star Party (targeting women); Science Festivals (World, NYC; Princeton U.; the USA Science and Engineering Festival); and the NYC Columbus Day Parade. Information was also provided about local science museums, citizen science projects, astronomy educational sites, and astronomy clubs to encourage lifelong learning. In 2010 I created Astronomy Festival on the National Mall (co-sponsored by the White House Office of Science and Technology Policy) with the participation of astronomy clubs, scientific institutions and with Tyco Brahe, Johannes Kepler, and Caroline Herschel making guest appearances. My programs include solar, optical, and radio telescope observations, hands-on activities, a live image projection system; large outdoor posters and banners; videos; hands-on activities, and edible astronomy demonstrations.My NASA-funded Music and Astronomy Under the Stars (MAUS) program (60 events 2009 - 2013) reached 50,000 music lovers at local parks and the Central Park Jazz, Newport Folk, Ravinia, or Tanglewood Music Festivals with classical, folk, pop/rock, opera, Caribbean, or county-western concerts assisted by astronomy clubs. Yo-Yo-Ma, the Chicago and Boston Symphony Orchestras, Ravi Coltrane, Esperanza Spalding, Phish, Blood Sweat and Tears, Deep Purple, Tony Orlando, and Wilco performed at these events. MAUS reached underserved groups and attracted large crowds. Young kids participated in this family learning experience - often the first time they looked through a telescope. While < 50% of the participants took part in a science activity in the past year, they

The Legends of Vasistha - A Note on the Vedanga Astronomy

Science.gov (United States)

Ôhashi, Y.

The author discusses some topics about the Vedanga astronomy, which is a kind of ancient Indian astronomy. The Vedanga (limb of the Veda) is a class of works regarded as auxiliary to the Veda. It consists of six divisions, one of which is astronomy.

γ astronomy

International Nuclear Information System (INIS)

Wolfendale, A.W.

1987-01-01

Some problems of gamma astronomy are discussed in the popular form. The most interesting research directions are considered:e + e - pair annihilation, 100 MeV gamma quanta sources, Cherenkov radiation gamma quanta recording and cosmic ray anisotropy. Special attention is paid to unique gamma quanta source - Cygnus X-3. The source possesses the highest luminosity in the gamma range

High-resolution mapping reveals linkage between genes in common bean cultivar Ouro Negro conferring resistance to the rust, anthracnose, and angular leaf spot diseases.

Science.gov (United States)

Valentini, Giseli; Gonçalves-Vidigal, Maria Celeste; Hurtado-Gonzales, Oscar P; de Lima Castro, Sandra Aparecida; Cregan, Perry B; Song, Qijian; Pastor-Corrales, Marcial A

2017-08-01

Co-segregation analysis and high-throughput genotyping using SNP, SSR, and KASP markers demonstrated genetic linkage between Ur-14 and Co-3 4 /Phg-3 loci conferring resistance to the rust, anthracnose and angular leaf spot diseases of common bean. Rust, anthracnose, and angular leaf spot are major diseases of common bean in the Americas and Africa. The cultivar Ouro Negro has the Ur-14 gene that confers broad spectrum resistance to rust and the gene cluster Co-3 4 /Phg-3 containing two tightly linked genes conferring resistance to anthracnose and angular leaf spot, respectively. We used co-segregation analysis and high-throughput genotyping of 179 F 2:3 families from the Rudá (susceptible) × Ouro Negro (resistant) cross-phenotyped separately with races of the rust and anthracnose pathogens. The results confirmed that Ur-14 and Co-3 4 /Phg-3 cluster in Ouro Negro conferred resistance to rust and anthracnose, respectively, and that Ur-14 and the Co-3 4 /Phg-3 cluster were closely linked. Genotyping the F 2:3 families, first with 5398 SNPs on the Illumina BeadChip BARCBEAN6K_3 and with 15 SSR, and eight KASP markers, specifically designed for the candidate region containing Ur-14 and Co-3 4 /Phg-3, permitted the creation of a high-resolution genetic linkage map which revealed that Ur-14 was positioned at 2.2 cM from Co-3 4 /Phg-3 on the short arm of chromosome Pv04 of the common bean genome. Five flanking SSR markers were tightly linked at 0.1 and 0.2 cM from Ur-14, and two flanking KASP markers were tightly linked at 0.1 and 0.3 cM from Co-3 4 /Phg-3. Many other SSR, SNP, and KASP markers were also linked to these genes. These markers will be useful for the development of common bean cultivars combining the important Ur-14 and Co-3 4 /Phg-3 genes conferring resistance to three of the most destructive diseases of common bean.

Evolving Perspectives on Astronomy Education and Public Outreach in Hawai'i

Science.gov (United States)

Kimura, Ka'iu; Slater, T.; Hamilton, J.; Takata, V.

2012-01-01

For the last several decades, well meaning astronomers and educators have worked diligently to provide astronomy education experiences to Native Hawaiians and visitors across all the islands. Much of the early education and public outreach (EPO) work was based on a philosophical perspective based on the notion of, "if we just make them aware of how wonderful astronomy is, then everyone will naturally support the development of astronomy in the islands.” In support of this goal, numerous teacher workshops were delivered and the first generation of the Maunakea Observatories Visitors’ Center was developed and funded. These projects were most frequently developed using Mainland thinking, in a Mainland style, with a Mainland agenda. Consequently, these efforts often failed to create even moderate impacts, whether in educational settings, or in terms of public outreach. In recent years, our understanding of effective EPO has evolved. This evolution has led to a shift in the locus of control, from the Mainland to the Islands; and in content, from "astronomy only” to "astronomy as part of the whole.” We have come to understand that successfully transformative EPO requires intertwining astronomy with teaching about culture, language and context. In response, the `Imiloa Astronomy Center was expanded to convolve historical and modern astronomy with Hawaiian culture and language. Moreover, the most successful astronomy EPO programs in the islands have been redesigned to reflect meaningful collaborations of schools, businesses, and the larger community that situate astronomy as part of a larger educational work of honoring the traditions of the past while simultaneously transforming the future. This evolution in thinking may serve as a model for the astronomy community's interaction with other regional communities.

AngularJS Performance: A Survey Study

OpenAIRE

Ramos, Miguel; Valente, Marco Tulio; Terra, Ricardo

2017-01-01

AngularJS is a popular JavaScript MVC-based framework to construct single-page web applications. In this paper, we report the results of a survey with 95 professional developers about performance issues of AngularJS applications. We report common practices followed by developers to avoid performance problems (e.g., use of third-party or custom components), the general causes of performance problems in AngularJS applications (e.g., inadequate architecture decisions taken by AngularJS users), a...

Angularly resolved characterization of ion beams from laser-ultrathin foil interactions

Science.gov (United States)

Scullion, C.; Doria, D.; Romagnani, L.; Ahmed, H.; Alejo, A.; Ettlinger, O. C.; Gray, R. J.; Green, J.; Hicks, G. S.; Jung, D.; Naughton, K.; Padda, H.; Poder, K.; Scott, G. G.; Symes, D. R.; Kar, S.; McKenna, P.; Najmudin, Z.; Neely, D.; Zepf, M.; Borghesi, M.

2016-09-01

Methods and techniques used to capture and analyze beam profiles produced from the interaction of intense, ultrashort laser pulses and ultrathin foil targets using stacks of Radiochromic Film (RCF) and Columbia Resin #39 (CR-39) are presented. The identification of structure in the beam is particularly important in this regime, as it may be indicative of the dominance of specific acceleration mechanisms. Additionally, RCF can be used to deconvolve proton spectra with coarse energy resolution while mantaining angular information across the whole beam.

Angularly resolved characterization of ion beams from laser-ultrathin foil interactions

International Nuclear Information System (INIS)

Scullion, C.; Doria, D.; Ahmed, H.; Alejo, A.; Jung, D.; Naughton, K.; Kar, S.; Zepf, M.; Romagnani, L.; Ettlinger, O.C.; Hicks, G.S.; Poder, K.; Najmudin, Z.; Gray, R.J.; Padda, H.; McKenna, P.; Green, J.; Scott, G.G.; Symes, D.R.; Neely, D.

2016-01-01

Methods and techniques used to capture and analyze beam profiles produced from the interaction of intense, ultrashort laser pulses and ultrathin foil targets using stacks of Radiochromic Film (RCF) and Columbia Resin #39 (CR-39) are presented. The identification of structure in the beam is particularly important in this regime, as it may be indicative of the dominance of specific acceleration mechanisms. Additionally, RCF can be used to deconvolve proton spectra with coarse energy resolution while mantaining angular information across the whole beam.

Angular Positioning Sensor for Space Mechanisms

Science.gov (United States)

Steiner, Nicolas; Chapuis, Dominique

2013-09-01

Angular position sensors are used on various rotating mechanisms such as solar array drive mechanisms, antenna pointing mechanisms, scientific instruments, motors or actuators.Now a days, potentiometers and encoders are mainly used for angular measurement purposes. Both of them have their own pros and cons.As alternative, Ruag Space Switzerland Nyon (RSSN) is developing and qualifying two innovative technologies of angular position sensors which offer easy implementation, medium to very high lifetime and high flexibility with regards to the output signal shape/type.The Brushed angular position sensor uses space qualified processes which are already flying on RSSN's sliprings for many years. A large variety of output signal shape can be implemented to fulfill customer requirements (digital, analog, customized, etc.).The contactless angular position sensor consists in a new radiation hard Application Specific Integrated Circuit (ASIC) based on the Hall effect and providing the angular position without complex processing algorithm.

Advances in astronomy and astrophysics

CERN Document Server

Kopal, Zdenek

1962-01-01

Advances in Astronomy and Astrophysics, Volume 1 brings together numerous research works on different aspects of astronomy and astrophysics. This book is divided into five chapters and begins with an observational summary of the shock-wave theory of novae. The subsequent chapter provides the properties and problems of T tauri stars and related objects. These topics are followed by discussions on the structure and origin of meteorites and cosmic dust, as well as the models for evaluation of mass distribution in oblate stellar systems. The final chapter describes the methods of polarization mea

Advances in astronomy and astrophysics

CERN Document Server

Kopal, Zdenek

1963-01-01

Advances in Astronomy and Astrophysics, Volume 2 brings together numerous research works on different aspects of astronomy and astrophysics. This volume is composed of six chapters and begins with a summary of observational record on twilight extensions of the Venus cusps. The next chapter deals with the common and related properties of binary stars, with emphasis on the evaluation of their cataclysmic variables. Cataclysmic variables refer to an object in one of three classes: dwarf nova, nova, or supernova. These topics are followed by discussions on the eclipse phenomena and the eclipses i

Advances in astronomy and astrophysics

CERN Document Server

Kopal, Zdenek

1966-01-01

Advances in Astronomy and Astrophysics, Volume 4 brings together numerous research works on different aspects of astronomy and astrophysics. This volume is composed of five chapters, and starts with a description of objective prism and its application in space observations. The next chapter deals with the possibilities of deriving reliable models of the figure, density distribution, and gravity field of the Moon based on data obtained through Earth-bound telescopes. These topics are followed by a discussion on the ideal partially relativistic, partially degenerate gas in an exact manner. A ch

Advances in astronomy and astrophysics

CERN Document Server

Kopal, Zdenek

1968-01-01

Advances in Astronomy and Astrophysics, Volume 6 brings together numerous research works on different aspects of astronomy and astrophysics. This volume is composed of five chapters, and starts with the description of improved methods for analyzing and classifying families of periodic orbits in a conservative dynamical system with two degrees of freedom. The next chapter describes the variation of fractional luminosity of distorted components of close binary systems in the course of their revolution, or the accompanying changes in radial velocity. This topic is followed by discussions on vari

Indian Astronomy: The Missing Link in Eurocentric History of Astronomy

Science.gov (United States)

Haque, Shirin; Sharma, Deva

2016-01-01

A comprehensive history of Astronomy should show in reasonable chronological order, the contributions from wherever they arise in the world, once they are reliably documented. However, the authors note that consistently, the extremely rich contributions from Ancient Indian scholars like Aryabatha and Bhramagupta are omitted in Eurocentric…

Teaching Astronomy with Podcasts of the APOD

Science.gov (United States)

Wagner, Robert M.

2017-01-01

The APOD website provides many excellent astronomy photos that are used to enhance introductory astronomy classes. For nearly six years, podcasts have been used to enhance learning in introductory astronomy classes at Harrisburg Area Community College. Daily 3-5 minute podcasts have been created and made available through iTunes to students in these classes at no charge. Students are asked to subscribe to the podcast collections and are quizzed on the images discussed throughout the semester. Because the images often focus on current findings in astronomy, the students are given instruction on findings that will not appear in their textbooks for several years. The students also receive a taste of some topics that may not be covered or that are just touched upon because of time limits in the classes. The podcasts have been used successfully with both traditional and fully online classes. The use of the podcasts enhances mobile learning as students can download and listen to the podcasts on their smartphones or tablets at their convenience. The student response to the podcasts has been excellent with some students noting that they continue to follow the website and podcasts even after they have completed the class. With mobile learning expanding, this is an excellent way to reach students and encourage them to further research the various topics in astronomy that are covered in the APOD images.

Instant AngularJS starter

CERN Document Server

Menard, Dan

2013-01-01

Get to grips with a new technology, understand what it is and what it can do for you, and then get to work with the most important features and tasks. This book is written in an easytoread style, with a strong emphasis on realworld, practical examples. Stepbystep explanations are provided for performing important tasks.This book is for web developers familiar with JavascriptIt doesn't cover the history of AngularJS, and it's not a pitch to convince you that AngularJS is the best framework on the entire web. It's a guide to help you learn everything you need to know about AngularJS in as few pa

AngularJS testing cookbook

CERN Document Server

Bailey, Simon

2015-01-01

This book is intended for developers who have an understanding of the basic principles behind both AngularJS and test-driven development. You, as a developer, are interested in eliminating the fear related to either introducing tests to an existing codebase or starting out testing on a fresh AngularJS application. If you're a team leader or part of a QA team with the responsibility of ensuring full test coverage of an application, then this book is ideal for you to comprehend the full testing scope required by your developers. Whether you're new to or are well versed with AngularJS, this book

An Online Tutor for Astronomy: The GEAS Self-Review Library

Science.gov (United States)

Vogt, Nicole P.; Muise, Amy Smith

2015-01-01

We introduce an interactive online resource for use by students and college instructors in introductory astronomy courses. The General Education Astronomy Source (GEAS) online tutor guides students developing mastery of core astronomical concepts and mathematical applications of general astronomy material. It contains over 12,000 questions, with…

High Angular Momentum Halo Gas: A Feedback and Code-independent Prediction of LCDM

Science.gov (United States)

Stewart, Kyle R.; Maller, Ariyeh H.; Oñorbe, Jose; Bullock, James S.; Joung, M. Ryan; Devriendt, Julien; Ceverino, Daniel; Kereš, Dušan; Hopkins, Philip F.; Faucher-Giguère, Claude-André

2017-07-01

We investigate angular momentum acquisition in Milky Way-sized galaxies by comparing five high resolution zoom-in simulations, each implementing identical cosmological initial conditions but utilizing different hydrodynamic codes: Enzo, Art, Ramses, Arepo, and Gizmo-PSPH. Each code implements a distinct set of feedback and star formation prescriptions. We find that while many galaxy and halo properties vary between the different codes (and feedback prescriptions), there is qualitative agreement on the process of angular momentum acquisition in the galaxy’s halo. In all simulations, cold filamentary gas accretion to the halo results in ˜4 times more specific angular momentum in cold halo gas (λ cold ≳ 0.1) than in the dark matter halo. At z > 1, this inflow takes the form of inspiraling cold streams that are co-directional in the halo of the galaxy and are fueled, aligned, and kinematically connected to filamentary gas infall along the cosmic web. Due to the qualitative agreement among disparate simulations, we conclude that the buildup of high angular momentum halo gas and the presence of these inspiraling cold streams are robust predictions of Lambda Cold Dark Matter galaxy formation, though the detailed morphology of these streams is significantly less certain. A growing body of observational evidence suggests that this process is borne out in the real universe.

High Angular Momentum Halo Gas: A Feedback and Code-independent Prediction of LCDM

Energy Technology Data Exchange (ETDEWEB)

Stewart, Kyle R. [Department of Mathematical Sciences, California Baptist University, 8432 Magnolia Ave., Riverside, CA 92504 (United States); Maller, Ariyeh H. [Department of Physics, New York City College of Technology, 300 Jay St., Brooklyn, NY 11201 (United States); Oñorbe, Jose [Max-Planck-Institut für Astronomie, Königstuhl 17, D-69117 Heidelberg (Germany); Bullock, James S. [Center for Cosmology, Department of Physics and Astronomy, The University of California at Irvine, Irvine, CA 92697 (United States); Joung, M. Ryan [Department of Astronomy, Columbia University, New York, NY 10027 (United States); Devriendt, Julien [Department of Physics, University of Oxford, The Denys Wilkinson Building, Keble Rd., Oxford OX1 3RH (United Kingdom); Ceverino, Daniel [Zentrum für Astronomie der Universität Heidelberg, Institut für Theoretische Astrophysik, Albert-Ueberle-Str. 2, D-69120 Heidelberg (Germany); Kereš, Dušan [Department of Physics, Center for Astrophysics and Space Sciences, University of California at San Diego, 9500 Gilman Dr., La Jolla, CA 92093 (United States); Hopkins, Philip F. [California Institute of Technology, 1200 E. California Blvd., Pasadena, CA 91125 (United States); Faucher-Giguère, Claude-André [Department of Physics and Astronomy and CIERA, Northwestern University, 2145 Sheridan Rd., Evanston, IL 60208 (United States)

2017-07-01

We investigate angular momentum acquisition in Milky Way-sized galaxies by comparing five high resolution zoom-in simulations, each implementing identical cosmological initial conditions but utilizing different hydrodynamic codes: Enzo, Art, Ramses, Arepo, and Gizmo-PSPH. Each code implements a distinct set of feedback and star formation prescriptions. We find that while many galaxy and halo properties vary between the different codes (and feedback prescriptions), there is qualitative agreement on the process of angular momentum acquisition in the galaxy’s halo. In all simulations, cold filamentary gas accretion to the halo results in ∼4 times more specific angular momentum in cold halo gas ( λ {sub cold} ≳ 0.1) than in the dark matter halo. At z > 1, this inflow takes the form of inspiraling cold streams that are co-directional in the halo of the galaxy and are fueled, aligned, and kinematically connected to filamentary gas infall along the cosmic web. Due to the qualitative agreement among disparate simulations, we conclude that the buildup of high angular momentum halo gas and the presence of these inspiraling cold streams are robust predictions of Lambda Cold Dark Matter galaxy formation, though the detailed morphology of these streams is significantly less certain. A growing body of observational evidence suggests that this process is borne out in the real universe.

Development of a Measuring System Based on LabVIEW for Angular Stiffness of Integrative Flexible Joint

International Nuclear Information System (INIS)

Liu, C J; Wan, D A

2006-01-01

In order to meet the need of development of integrative flexible joint, this paper presents a higher precision measuring system for angular stiffness test of integrative flexible joint. The main parts of the system include PC, precision motorized goniometric stage, precision motorized rotary stage and high accuracy torque sensor. The measuring and control program is developed on the platform of LabVIEW. The measuring system developed has angular resolution at 0.00032 deg. (about 1'') theoretically in determining the angular displacement of the joint round its equatorial axis and torque accuracy at 0.005 mN · m. The developed program, which presents a friendly GUI, can implement the data acquisition and processing, measuring procedure automatically. In comparison with other measuring devices with similar purposes, the measuring device can improve the measuring efficiency and accuracy distinctly while has advantages of simple configuration, low cost and high stability

Differences between US Women’s and Men’s Careers in Astronomy: Results from the Longitudinal Study of Astronomy Graduate Students

Science.gov (United States)

Ivie, Rachel; White, Susan; Chu, Raymond Y.

2015-08-01

The Longitudinal Study of Astronomy Graduate Students (LSAGS), a joint project of the American Astronomical Society (AAS) and the American Institute of Physics (AIP), emerged from the Women in Astronomy II conference held in Pasadena, CA, USA in 2003. At the conference, concern about possible differential attrition for women arose from the relatively high percentage of female junior (student) AAS members compared to the lower representation of women among astronomy faculty members.The Committee for the Status of Women in Astronomy (CSWA) and the AAS Council concluded that a longitudinal study was needed to collect data about which variables affect career choices in astronomy and to determine whether any of these variables exert a disproportionate force on either sex. In 2007-08, the project team, under the direction of Rachel Ivie, Associate Director of AIP’s Statistical Research Center (SRC), asked all graduate students in astronomy and astrophysics in the US (~1500) to complete the first survey. The LSAGS follows this same group of students as they leave graduate school and enter their careers. In 2012-13, more than 800 responded to the second survey, and most had completed PhDs. We plan a third round of data collection in 2015.Results from the study show that there are statistically significant differences between women and men in dissertation research methods, PhD subfield, and ratings of graduate school advisors. We found that after graduate school, women were more likely than men to take a break from work of six months or longer and to have made accommodations for a partner’s career opportunities (the “two-body problem”). In turn, women were more likely to work outside the field of astronomy because they were more likely to have experienced the “two-body problem.” In addition, we found women were more likely than men to have experienced harassment or discrimination at school or work. Finally, even while controlling for employment sector and years

Chandra's Ultimate Angular Resolution: Studies of the HRC-I Point Spread Function

Science.gov (United States)

Juda, Michael; Karovska, M.

2010-03-01

The Chandra High Resolution Camera (HRC) should provide an ideal imaging match to the High-Resolution Mirror Assembly (HRMA). The laboratory-measured intrinsic resolution of the HRC is 20 microns FWHM. HRC event positions are determined via a centroiding method rather than by using discrete pixels. This event position reconstruction method and any non-ideal performance of the detector electronics can introduce distortions in event locations that, when combined with spacecraft dither, produce artifacts in source images. We compare ray-traces of the HRMA response to "on-axis" observations of AR Lac and Capella as they move through their dither patterns to images produced from filtered event lists to characterize the effective intrinsic PSF of the HRC-I. A two-dimensional Gaussian, which is often used to represent the detector response, is NOT a good representation of the intrinsic PSF of the HRC-I; the actual PSF has a sharper peak and additional structure which will be discussed. This work was supported under NASA contract NAS8-03060.

Division X, XII / Commission 40, 41 / Working Group Radio Astronomy

NARCIS (Netherlands)

Kellermann, Kenneth; Orchiston, Wayne; Davies, Rod; Gurvits, Leonid; Ishiguro, Masato; Lequeux, James; Swarup, Govind; Wall, Jasper; Wielebinski, Richard; van Woerden, Hugo

The IAU Working Group on Historical Radio Astronomy (WGHRA) was formed at the 2003 General Assembly of the IAU as a Joint Working Group of Commissions 40 (Radio Astronomy) and 41 (History of Astronomy), in order to: a) assemble a master list of surviving historically-significant radio telescopes and

Online Scholarly Conversations in General Education Astronomy Courses

Science.gov (United States)

Cai, Qijie; Wong, Ka-Wah

2018-01-01

In general education astronomy courses, many students are struggling with understanding the foundational concepts and theories in astronomy. One of the possible reasons is that, due the large class size, many of the courses are taught using a lecture mode, where human interactions and active learning are limited (Freeman et al., 2014). To address this challenge, we have applied the knowledge building framework (Scardamalia & Bereiter, 2006) to design an online collaborative learning component, called Scholarly Conversations, to be integrated into a general education astronomy course at a public, comprehensive university.During Scholarly Conversations, students are treated as scholars to advance knowledge frontiers (Scardamalia & Bereiter, 2006). The whole process involves the creation of new ideas and requires discourse and collective work for the advancement and creation of artifacts, such as theories and models (van Aalst, 2009). Based on the knowledge building principles (Scardamalia, 2002; Zhang, Scardamalia, Reeve, & Messina, 2009), several features have been built into Scholarly Conversations so that students are guided to deepen understanding of the astronomy concepts through three phases: knowledge sharing, knowledge construction and knowledge building, and reflections on learning growth (van Aalst, 2009; Cai, 2017). The online Scholarly Conversation is an extension of the lecture component of the general education astronomy course. It promotes student interactions and collaborative learning, and provides scaffolds for students to construct meanings of the essential concepts in astronomy through social learning and online technology. In this presentation, we will explain the specific design principles of the online Scholarly Conversation, and share the artifacts created to facilitate the online conversations in an general education astronomy course.Note: This project has been supported by the College of Education Research Grant Program at Minnesota State

Spiral Transformation for High-Resolution and Efficient Sorting of Optical Vortex Modes

Science.gov (United States)

Wen, Yuanhui; Chremmos, Ioannis; Chen, Yujie; Zhu, Jiangbo; Zhang, Yanfeng; Yu, Siyuan

2018-05-01

Mode sorting is an essential function for optical multiplexing systems that exploit the orthogonality of the orbital angular momentum mode space. The familiar log-polar optical transformation provides a simple yet efficient approach whose resolution is, however, restricted by a considerable overlap between adjacent modes resulting from the limited excursion of the phase along a complete circle around the optical vortex axis. We propose and experimentally verify a new optical transformation that maps spirals (instead of concentric circles) to parallel lines. As the phase excursion along a spiral in the wave front of an optical vortex is theoretically unlimited, this new optical transformation can separate orbital angular momentum modes with superior resolution while maintaining unity efficiency.

The Cambridge Illustrated History of Astronomy

Science.gov (United States)

Hoskin, Michael

Expertly written and lavishly illustrated, The Cambridge Illustrated History of Astronomy offers a unique account of astronomical theory and practice from antiquity to the present day. How did Moslems of the Middle Ages use astronomy to calculate the direction of Mecca from far-flung corners of the Islamic world? Who was the only ancient Greek to suspect that the earth might revolve around the sun? How did Christopher Columbus abuse his knowledge of a lunar eclipse predicted by an astronomical almanac? Packed with anecdotes and intriguing detail, this book describes how we observed the sky and interpreted what we saw at different periods of history; how this influenced our beliefs and mythology; and how great astronomers contributed to what we now know. The result is a lively and highly visual history of astronomy - a compelling read for specialists and non-specialists alike.

Gamma ray astronomy

International Nuclear Information System (INIS)

Broomhead, Laurent.

1980-01-01

The nuclear gamma astronomy is presented, in particular the Gamma Ray Observatory, an enormous eight tonnes machine fitted with gamma telescopes, scheduled for launching around 1985. It is thereby hoped to study the natural nuclear reactions which occur when stars explode [fr

Physics and astronomy

CSIR Research Space (South Africa)

Moraal, H

2009-01-01

Full Text Available The chapter is about physics and astronomy. The chapter gives a background about the origins of physics in South Africa. After the CSIR was founded in 1945, physics emerged as a nationwide and unified discipline. The authors show how physics...

Expectations of Students about Astronomy in High School

Science.gov (United States)

Peixoto, Denis Eduardo; Kleinke, Maurício Urban

2016-12-01

Current literature reports that the astronomy education is motivating and interesting for basic education, but the content suggested by the national curriculum guidelines do not seem to attract students and teachers in order to transcend the discipline of Science in the elementary School or Physics in High School. By applying a questionnaire to 80 students of High School and participants of Brazilian Olympiad of Astronomy and Astronautics of two schools of São Paulo state, we obtained results that indicate that astronomy topics that really motivate students are topics linked to science fiction and current research, which are the subject of extensive media release and have a strong interdisciplinary character. At the end of the work we suggest a new context for astronomy education, by inserting topics combined with other areas of knowledge to what we call “interdisciplinary astrophysics teaching”.

Variation in angular velocity and angular acceleration of a particle in rectilinear motion

International Nuclear Information System (INIS)

Mashood, K K; Singh, V A

2012-01-01

We discuss the angular velocity and angular acceleration associated with a particle in rectilinear motion with constant acceleration. The discussion was motivated by an observation that students and even teachers have difficulty in ascribing rotational motion concepts to a particle when the trajectory is a straight line. We present some details of our observations. A formal derivation of ω and α is presented which reveals ‘surprising’ and non-intuitive aspects, namely non-monotonic behaviour with an associated extremum. The special case of constant velocity is studied and we find that angular acceleration associated with it also has an extremum. We discuss a plausible source of difficulty. (paper)

The ASTRO-H (Hitomi) X-Ray Astronomy Satellite

Science.gov (United States)

Takahashi, Tadayuki; Kokubun, Motohide; Mitsuda, Kazuhisa; Kelley, Richard; Ohashi, Takaya; Aharonian, Felix; Akamatsu, Hiroki; Akimoto, Fumie; Allen, Steve; Anabuki, Naohisa;

What types of astronomy images are most popular?

Science.gov (United States)

Allen, Alice; Bonnell, Jerry T.; Connelly, Paul; Haring, Ralf; Lowe, Stuart R.; Nemiroff, Robert J.

2015-01-01

Stunning imagery helps make astronomy one of the most popular sciences -- but what types of astronomy images are most popular? To help answer this question, public response to images posted to various public venues of the Astronomy Picture of the Day (APOD) are investigated. APOD portals queried included the main NASA website and the social media mirrors on Facebook, Google Plus, and Twitter. Popularity measures include polls, downloads, page views, likes, shares, and retweets; these measures are used to assess how image popularity varies in relation to various image attributes including topic and topicality.

Southern Africa Regional Office of Astronomy for Development: A New Hub for Astronomy for Development

Science.gov (United States)

Siseho Mutondo, Moola

2015-08-01

A new Astronomy for Development hub needs innovative tools and programs. SAROAD is developing exciting tools integrating Raspberry Pi® technology to bring cost-effective astronomy content to learning centres. SAROAD would also like to report achievements in realising the IAU's strategic plan. In order to manage, evaluate and coordinate regional IAU capacity building programmes, including the recruitment and mobilisation of volunteers, SAROAD has built an intranet that is accessible to regional members upon request. Using this resource, regional members can see and participate in regional activities. This resource also forms the foundation for closer collaboration between SAROAD member countries. SAROAD has commenced with projects in the three Task Force areas of Universities and Research, Children and Schools and Public Outreach. Under the three Task Force areas, a total of seven projects have commenced in Zambia. A further two projects involve the collaboration of Zambia and other regional member countries in order to foster engagement with important regional astronomy facilities (e.g. SKA). SAROAD has identified the IAU’s International Year of Light and a starting point for offering regional support for IAU-endorsed global activities. SAROAD has set up a hub dedicated to regional events and activities about the International Year of Light. SAROAD has a database of regional authorities to enable contact with the region's decision makers and experts. SAROAD will hold an annual event which brings forum for astronomy for development. The creation of the database and the SAROAD Road show is a first step towards this goal. The SAROAD website has helped to advertise upcoming events for astronomy development and education; it is used to provide advice, guidance and information for astronomers in all countries in the Southern Africa. Fundraising is the primary goal for SAROAD in 2015 towards financial self-sufficiency by 2020. We report on the methods that work best

Bragg reflection transmission filters for variable resolution monochromators

International Nuclear Information System (INIS)

Chapman, D.

1989-01-01

There are various methods for improving the angular and spectral resolution of monochromator and analyzer systems. The novel system described here, though limited to higher x-ray energies (>20keV), is based on a dynamical effect occurring on the transmitted beam with a thin perfect crystal plate set in the Bragg reflection case. In the case of Bragg reflection from a perfect crystal, the incident beam is rapidly attenuated as it penetrates the crystal in the range of reflection. This extinction length is of the order of microns. The attenuation length, which determines the amount of normal transmission through the plate is generally much longer. Thus, in the range of the Bragg reflection the attenuation of the transmitted beam can change by several orders of magnitude with a small change in energy or angle. This thin crystal plate cuts a notch in the transmitted beam with a width equal to its Darwin width, thus acting as a transmission filter. When used in a non-dispersive mode with other monochromator crystals, the filter when set at the Bragg angle will reflect the entire Darwin width of the incident beam and transmit the wings of the incident beam distribution. When the element is offset in angle by some fraction of the Darwin width, the filter becomes useful in adjusting the angular width of the transmitted beam and removing a wing. Used in pairs with a symmetric offset, the filters can be used to continuously adjust the intrinsic angular divergence of the beam with good wing reduction. Instances where such filters may be useful are in improving the angular resolution of a small angle scattering camera. These filters may be added to a Bonse-Hart camera with one pair on the incident beam to reduce the intrinsic beam divergence and a second pair on the analyzer arm to improve the analyzer resolution. 2 refs., 3 Figs

An alternative resolution to the Mansuripur paradox

Science.gov (United States)

Redfern, Francis

2016-04-01

In 2013 an article published online by the journal Science declared that the paradox proposed by Masud Mansuripur was resolved. This paradox concerns a point charge-Amperian magnetic dipole system as seen in a frame of reference where they are at rest and one in which they are moving. In the latter frame an electric dipole appears on the magnetic dipole. A torque is then exerted upon the electric dipole by the point charge, a torque that is not observed in the at-rest frame. Mansuripur points out this violates the relativity principle and suggests the Lorentz force responsible for the torque be replaced by the Einstein-Laub force. The resolution of the paradox reported by Science, based on numerous papers in the physics literature, preserves the Lorentz force but depends on the concept of hidden momentum. Here I propose a different resolution based on the overlooked fact that the charge-magnetic dipole system contains linear and angular electromagnetic field momentum. The time rate of change of the field angular-momentum in the frame through which the system is moving cancels that due to the charge-electric dipole interaction. From this point of view hidden momentum is not needed in the resolution of the paradox.

Fission fragment angular momentum

International Nuclear Information System (INIS)

Frenne, D. De

1991-01-01

Most of the energy released in fission is converted into translational kinetic energy of the fragments. The remaining excitation energy will be distributed among neutrons and gammas. An important parameter characterizing the scission configuration is the primary angular momentum of the nascent fragments. Neutron emission is not expected to decrease the spin of the fragments by more than one unit of angular momentum and is as such of less importance in the determination of the initial fragment spins. Gamma emission is a suitable tool in studying initial fragment spins because the emission time, number, energy, and multipolarity of the gammas strongly depend on the value of the primary angular momentum. The main conclusions of experiments on gamma emission were that the initial angular momentum of the fragments is large compared to the ground state spin and oriented perpendicular to the fission axis. Most of the recent information concerning initial fragment spin distributions comes from the measurement of isomeric ratios for isomeric pairs produced in fission. Although in nearly every mass chain isomers are known, only a small number are suitable for initial fission fragment spin studies. Yield and half-life considerations strongly limit the number of candidates. This has the advantage that the behavior of a specific isomeric pair can be investigated for a number of fissioning systems at different excitation energies of the fragments and fissioning nuclei. Because most of the recent information on primary angular momenta comes from measurements of isomeric ratios, the global deexcitation process of the fragments and the calculation of the initial fragment spin distribution from measured isomeric ratios are discussed here. The most important results on primary angular momentum determinations are reviewed and some theoretical approaches are given. 45 refs., 7 figs., 2 tabs

Lithuanian Astronomy

Science.gov (United States)

Sudzius, J.; Murdin, P.

2002-01-01

Lithuanian folklore, archaic calendars and terminology show that Lithuanians were interested in astronomy from ancient times. A lot of celestial bodies have names of Lithuanian origin that are not related to widely accepted ancient Greek mythology. For example, the Milky Way is named `Pauksciu Takas' (literally the way of birds), the constellation of the Great Bear `Didieji Grizulo Ratai' (literal...

Angular Acceleration without Torque?

Science.gov (United States)

Kaufman, Richard D.

2012-01-01

Hardly. Just as Robert Johns qualitatively describes angular acceleration by an internal force in his article "Acceleration Without Force?" here we will extend the discussion to consider angular acceleration by an internal torque. As we will see, this internal torque is due to an internal force acting at a distance from an instantaneous center.

Characterisation of radiation damage in perovskite using high angular resolution electron channeling x-ray spectroscopy (HARECXS)

International Nuclear Information System (INIS)

Smith, K.L.; Zaluzec, N.J.

2002-01-01

Full text: Predicting and/or modelling the occurrence of radiation damage induced defects and their effects on physical properties (eg. amorphisation induced swelling, electrical conductivity., optical response etc.) in ceramic phases requires knowledge of the displacement energies, E d , of cations and anions in those phases. In this study, High Angular Resolution Electron Channelling X-ray Spectroscopy (HARECXS) spectra were collected from perovskite (CaTiO 3 ) samples that had been exposed to high-energy electrons or high-energy heavy ions. Calculations based on experimental data were then used to indicate the E d of the cations in perovskite. The HARECXS measurements were conducted on a Philips EM 420T AEM (LaB6 source, operated at 120 kV) fitted with an EDAX ultra thin window Si(Li) detector. The specimen was first manually oriented to an appropriate zone axis. Then control of the relative orientation of the incident probe was accomplished via direct computer control of the beam tilt coils, Typical acquisition times for a complete two-dimensional scan were 18-24 hours, while one dimensional scans ranged from 1-5 hours. Our experiments established that: a) HARECXS can detect radiation damage in perovskite caused by either high energy heavy ions or high energy electrons, b) the HARECXS signature of perovskite shows a systematic change with ion dose, c) HARECXS detects damage in perovskite that has been irradiated with 900kV electrons and does not detect damage in perovskite that has been irradiated with 620kV electrons, indicating the existance of an electron irradiation damage threshold. Calculations based on the latter results indicate that the displacement energy, E d of calcium and titanium in perovskite lie between 50 and 85eV. Copyright (2002) Australian Society for Electron Microscopy Inc

Astronomy Education: a Challenge for Contemporary Education

Science.gov (United States)

Metaxa, M.

2010-07-01

Tales around the World give visibility to local, national and international fundamental connection that always existed between people and the night sky that means Astronomy. In this paper we discuss and analyze further the role of Astronomy Education for achieving an integrated concept of education, one that enables individuals to adapt to a rapidly changing social, economic and cultural environment, and to continue to learn throughout life. It is no longer enough to learn how to read, write and count. We also discuss and present initiatives undertaken in the context of various national, and international educational projects in Greece as best practices on how Astronomy Education can actually reinforce the Contemporary Education.

Contribution to the popularization of the astronomy

Science.gov (United States)

Markishki, Pencho

The purpose of this report is the representation of a WEB-book, related to astronomy, astro-photography, optics and some additional areas that have direct practice for the amateur astronomers. The popularization of astronomy worldwide is the purpose of many amateur astronomers. It is interesting and maybe fascinated, requires often innovative solutions from the hobby star observers. Today it is possible to share the science information by different methods, using the modern information technologies - a possibility used by the amateur astronomers too. In Internet existing currently thousands of WEB- sites, related to astronomy, completed training programs developed by amateur astronomers are included. They are addressed often to the schools, to the hobby beginners or to the wide audience.

High-resolution imaging gamma-ray spectroscopy with externally segmented germanium detectors

Science.gov (United States)

Callas, J. L.; Mahoney, W. A.; Varnell, L. S.; Wheaton, W. A.

1993-01-01

Externally segmented germanium detectors promise a breakthrough in gamma-ray imaging capabilities while retaining the superb energy resolution of germanium spectrometers. An angular resolution of 0.2 deg becomes practical by combining position-sensitive germanium detectors having a segment thickness of a few millimeters with a one-dimensional coded aperture located about a meter from the detectors. Correspondingly higher angular resolutions are possible with larger separations between the detectors and the coded aperture. Two-dimensional images can be obtained by rotating the instrument. Although the basic concept is similar to optical or X-ray coded-aperture imaging techniques, several complicating effects arise because of the penetrating nature of gamma rays. The complications include partial transmission through the coded aperture elements, Compton scattering in the germanium detectors, and high background count rates. Extensive electron-photon Monte Carlo modeling of a realistic detector/coded-aperture/collimator system has been performed. Results show that these complicating effects can be characterized and accounted for with no significant loss in instrument sensitivity.

Preservice elementary teachers learning of astronomy

Science.gov (United States)

Fidler, Chuck Gary

The dissertation presents a new approach for the study of preservice elementary teacher astronomy education. The approach suggests that learning astronomical concepts are facilitated by greater sophistication in scale perception and spatial-aptitude. This dissertation is underscored by the national call for elementary science education reform efforts and suggests certain strategies shown more effective for the development of accurate astronomical comprehension. The present research study describes how preservice elementary teachers conceptualize and communicate ideas about Space. Instead of assuming a universal mental conception of cosmic orientations and relationships, the dissertation claims that the perception of Space related dimensions vary among preservice elementary teachers. Furthermore, the dissertation suggests individual perceptions of the scale sizes and orientations of celestial systems have direct influences on mental models used to organize and communicate astronomical information. The development of inaccurate mental models of the scaled dimensions of Space may perpetuate the teacher-student cycle of misconception and naive-theory generation among children in elementary education settings. The ability to conceptualize the vast cosmos is facilitated by the minds ability to think about vast scales and orientations of celestial objects. The Earth-based perspective of astronomy education compels the learner to think about astronomical principles within imaginary frames of reference and across unfamiliar scaled dimensions. Therefore, mental astronomical model building is underscored by the perception of scale and cosmic spatiality. This study suggests these cognitive skill sets are interconnected and facilitate the learning of accurate astronomy principles; as well as play an important role when designing an astronomy education program for preservice elementary teachers. This research study is comprised of three separate standalone articles designed and

Changes in Preservice Teacher Attitudes toward Astronomy within a Semester-Long Astronomy Instruction and Four-Year-Long Teacher Training Programme

Science.gov (United States)

Ucar, Sedat; Demircioglu, Tuba

2011-01-01

Teachers' attitudes toward science, especially toward astronomy, are considered to be an important aspect of teaching and learning astronomy in school. Research findings to date remain inconclusive as to whether attitudes toward science change with the science courses taken or with increasing achievement. Therefore, preservice teacher attitudes…

Encouraging Student Participation in Large Astronomy Courses

Science.gov (United States)

Willoughby, Shannon D.

2012-01-01

Introductory astronomy is one of the most widely taught classes in the country and the majority of the students who take these classes are non-science majors. Because this demographic of students makes up the majority of astronomy enrollments, it is especially important as instructors that we do our best to make sure these students don't finish…

Julia and Python in Astronomy: Better Together

OpenAIRE

Barbary, Kyle

2016-01-01

Astronomers love Python because it is open source, easy to learn, and has a tremendous ecosystem for scientific computing. The Julia programming language has many of those same characteristics. In this talk, I discuss Julia, its use in astronomy and the growing ecosystem of astronomy packages, particularly those managed by the JuliaAstro organization (http://JuliaAstro.github.io).

The cost of publishing in Danish astronomy

DEFF Research Database (Denmark)

Dorch, Bertil F.

I investigate the cost of publishing in Danish astronomy on a fine scale, including all direct publication costs: The figures show how the annual number of publications with authors from Denmark in astronomy journals increased by a factor approximately four during 15 years (Elsevier’s Scopus...... database), and the increase of the corresponding potential (maximum) cost of publishing....

Probing the Spatial Distribution of the Interstellar Dust Medium by High Angular Resolution X-ray Halos of Point Sources

Science.gov (United States)

Xiang, Jingen

X-rays are absorbed and scattered by dust grains when they travel through the interstellar medium. The scattering within small angles results in an X-ray ``halo''. The halo properties are significantly affected by the energy of radiation, the optical depth of the scattering, the grain size distributions and compositions, and the spatial distribution of dust along the line of sight (LOS). Therefore analyzing the X-ray halo properties is an important tool to study the size distribution and spatial distribution of interstellar grains, which plays a central role in the astrophysical study of the interstellar medium, such as the thermodynamics and chemistry of the gas and the dynamics of star formation. With excellent angular resolution, good energy resolution and broad energy band, the Chandra ACIS is so far the best instrument for studying the X-ray halos. But the direct images of bright sources obtained with ACIS usually suffer from severe pileup which prevents us from obtaining the halos in small angles. We first improve the method proposed by Yao et al to resolve the X-ray dust scattering halos of point sources from the zeroth order data in CC-mode or the first order data in TE mode with Chandra HETG/ACIS. Using this method we re-analyze the Cygnus X-1 data observed with Chandra. Then we studied the X-ray dust scattering halos around 17 bright X-ray point sources using Chandra data. All sources were observed with the HETG/ACIS in CC-mode or TE-mode. Using the interstellar grain models of WD01 model and MRN model to fit the halo profiles, we get the hydrogen column densities and the spatial distributions of the scattering dust grains along the line of sights (LOS) to these sources. We find there is a good linear correlation not only between the scattering hydrogen column density from WD01 model and the one from MRN model, but also between N_{H} derived from spectral fits and the one derived from the grain models WD01 and MRN (except for GX 301-2 and Vela X-1): N

Angular-momentum transport in nuclear collisions

International Nuclear Information System (INIS)

Wolschin, G.; Ayik, S.; Noerenberg, W.

1978-01-01

Among the various relaxation processes that can be observed in heavy-ion collisions, the dissipation of relative angular momentum into intrinsic angular momentum of the fragments attracts increasing attention. Here we present a transport theoretical description of angular-momentum and mass transport that allows for a transparent interpretation of the data. (orig.) [de

AngularJS test-driven development

CERN Document Server

Chaplin, Tim

2015-01-01

This book is for developers who want to learn about AngularJS development by applying testing techniques. You are assumed to have a basic knowledge and understanding of HTML, JavaScript, and AngularJS.

NASE Training Courses in Astronomy for Teachers throughout the World

Science.gov (United States)

Ros, Rosa M.

2012-01-01

Network for Astronomy School Education, NASE, is a project that is organizing courses for teachers throughout the entire world. The main objective of the project is to prepare secondary and primary school teachers in astronomy. Students love to know more about astronomy and teachers have the opportunity to observe the sky that every school has…

Synthesis imaging in radio astronomy

International Nuclear Information System (INIS)

Perley, R.A.; Schwab, F.R.; Bridle, A.H.

1989-01-01

Recent advances in techniques and instrumentation for radio synthesis imaging in astronomy are discussed in a collection of review essays. Topics addressed include coherence in radio astronomy, the interferometer in practice, primary antenna elements, cross correlators, calibration and editing, sensitivity, deconvolution, self-calibration, error recognition, and image analysis. Consideration is given to wide-field imaging (bandwidth and time-average smearing, noncoplanar arrays, and mosaicking), high-dynamic-range imaging, spectral-line imaging, VLBI, solar imaging with a synthesis telescope, synthesis imaging of spatially coherent objects, noise in images of very bright sources, synthesis observing strategies, and the design of aperture-synthesis arrays

Informal Education: Slacker Astronomy Podcasts

Science.gov (United States)

Price, A.

2005-12-01

Slacker Astronomy is a weekly podcast about astronomy begun in February, 2005. Each week we cover a recent astronomical news event. We present it with humor and silliness, yet we respect the intelligence of the audience and do not ``dumb it down." Since we are professional astronomers we often cover items ignored by traditional press. We currently have around 10,000 loyal weekly listeners. All our shows are rated for content and available to the public under the Creative Commons license. Both scripts and audio are also used as source material by parents, teachers and planetarium directors.

ACDA Thirty Years of Popularization of Astronomy in Colombia

Science.gov (United States)

Ocampo, W.; Higuera-G., Mario A.

2017-07-01

The Colombian Association of Astronomical Studies (ACDA) is a Non Profit Organization with thirty years of permanent efforts for the popularization of astronomy and related sciences in Colombia. ACDA put together amateur and profesional astronomers, as well as interested people. We surely had left a footprint on uncountable number of attending people to our activities, members and former members, and have supported the process of building a new society, with more awareness on the importance of science. We devote our efforts to our members and general people, to keep them motivated, support them and follow each member own interests in order to expand and spread their knowledge. In order to achieve our goals we have develop several strategies as: acquire of didactic material and optical instruments, video projections and discussion, astronomical observations, visits to observatories and planetariums, attending conferences and events, and mainly a weekly Saturday morning talk at the Bogotá Planetarium. ACDA has had different study teams on several fields including: Planetary Systems, Astrobiology, Space Exploration, Cosmology, History of Astronomy and Radioastronomy. ACDA has a national brandname on Astronomy due to seriousness and quality of its projects. A good list of members have become profesional astronomers. From our experience we can say: astronomy is a fertile field to teach science, in general there is an absence of astronomy culture in the public, our best communication experience are astronomical observations, explained astronomy movies and colloquiums, our best public are kids and aged people and finally, social networks gave dynamics to our astronomy spreading initiative.

Very high energy gamma-ray astronomy

International Nuclear Information System (INIS)

Weekes, T.C.

1988-01-01

Current interest in gamma-ray astronomy at energies above 100 GeV comes from the identification of Cygnus X-3 and other X-ray binaries as sources. In addition there are reports of emission from radio pulsars and a variety of other objects. The statistical significance of many of the observations is not high and many reported effects await confirmation, but there are a sufficient number of independent reports that very high energy gamma-ray astronomy must now be considered to have an observational basis. The observations are summarized with particular emphasis on those reported since 1980. The techniques used - the detection of small air showers using the secondary photons and particles at ground level - are unusual and are described. Future prospects for the field are discussed in relation to new ground-based experiments, satellite gamma-ray studies and proposed neutrino astronomy experiments. (orig.) With 296 refs

Citizen Astronomy in China: An Overview

Science.gov (United States)

Ye, Quan-Zhi

2018-01-01

Citizen astronomers have benefited from technological advancements in the recent decades as they fill the scientific gaps left by professional astronomers, in the areas such as time domain observations, visual classification and data mining. Here I present an overview of the current status of citizen astronomy in China. Chinese citizen astronomers have made a visible contribution in the discoveries of new objects; however, comparing to their counterparts in the western world, they appear to be less interested in researches that do not involve making new discovery, such as visual classification, long-term monitoring of objects, and data mining. From a questionnaire survey that aimed to investigate the motivation of Chinese citizen astronomers, we find that this population is predominantly male (92%) who mostly reside in economically developed provinces. A large fraction (69%) of the respondents are students and young professionals younger than the age of 25, which differs significantly from the occupation and age distribution of typical Chinese Internet users as well as the user distribution of large international citizen science projects such as the Galaxy Zoo. This suggests that youth generation in China is more willing to participate citizen astronomy research than average generation. Additionally, we find that interests in astronomy, desire to learn new knowledges, have a fun experience and meet new friends in the community are all important driving factors for Chinese citizen astronomers to participate research. This also differs from their counterparts in western countries. With a large youth population that is interested in astronomy as well as a number of large astronomical facilities that are being planned or built, we believe that citizen astronomy in China has a vast potential. Timely and proper guidance from the professionals will be essential to help citizen astronomers to fulfill this potential.

Astronomy Courses which Emphasize Communication Skills

Science.gov (United States)

Dinerstein, H. L.

1998-12-01

The ability to communicate effectively, both in oral and written form, is crucial for success in almost any career path. Furthermore, being able to effectively communicate information requires a high level of conceptual mastery of the material. For these reasons, I have incorporated practice in communication into courses at a variety of levels, ranging from non-science-major undergraduate courses to graduate courses. I briefly describe the content of these courses, particularly the communication-related component. The first, Ast 309N, ``Astronomy Bizarre: Stars and Stellar Evolution," is an elective which follows one semester of general introductory astronomy for non-majors. Instead of homework problems, the students complete a sequence of writing assignments of graduated complexity, beginning with simple tasks such as writing abstracts and critiques of assigned readings, and moving on to writing term papers which require literature research and a short science fiction story incorporating accurate depictions of relativistic effects. In Ast 175/275, a ``Journal Club" course for upper-division astronomy majors, students read articles in the professional literature and give short oral presentations to the rest of the class. To build up their understanding of a topic, we work through the ``paper trail" of key papers on topics with exciting recent developments, such as extrasolar planets, gravitational lenses, or gamma-ray bursts. Finally, in a seminar course for first-semester astronomy graduate students (Ast 185C) that broadly addresses professional development issues, I include a practice AAS oral session, with the students giving 5-minute presentations on a journal paper of their choice. This seminar course also examines career paths and employment trends, the peer review process for papers and proposals, professional norms and ethics, and other topics. Syllabi for these and other courses I teach regularly can be found from my home page (http://www.as.utexas.edu/astronomy/people/dinerstein).

Student comprehension of mathematics through astronomy

Science.gov (United States)

Search, Robert

The purpose of this study is to examine how knowledge of astronomy can enhance college-level learning situations involving mathematics. The fundamental symbiosis between mathematics and astronomy was established early in the 17th century when Johannes Kepler deduced the 3 basic laws of planetary motion. This mutually harmonious relationship between these sciences has been reinforced repeatedly in history. In the early 20th century, for example, astronomer Arthur Eddington used photographic evidence from a 1919 solar eclipse to verify Einstein's mathematical theory of relativity. This study was conducted in 5 undergraduate mathematics classes over the course of 2 years. An introductory course in ordinary differential equations, taught in Spring Semester 2013, involved 4 students. A similar course in Spring Semester 2014 involved 6 students, a Summer Semester 2014 Calculus II course involved 2 students, and a Summer 2015 Astronomy course involved 8 students. The students were asked to use Kepler's astronomical evidence to deduce mathematical laws normally encountered on an undergraduate level. They were also asked to examine the elementary mathematical aspects involved in a theoretical trajectory to the planet Neptune. The summer astronomy class was asked to draw mathematical conclusions about large numbers from the recent discoveries concerning the dwarf planet Pluto. The evidence consists primarily of videotaped PowerPoint presentations conducted by the students in both differential equations classes, along with interviews and tests given in all the classes. All presentations were transcribed and examined to determine the effect of astronomy as a generator of student understanding of mathematics. An analysis of the data indicated two findings: definite student interest in a subject previously unknown to most of them and a desire to make the mathematical connection to celestial phenomena.

76 FR 7882 - Astronomy and Astrophysics Advisory Committee; Notice of Meeting

Science.gov (United States)

2011-02-11

... NATIONAL SCIENCE FOUNDATION Astronomy and Astrophysics Advisory Committee; Notice of Meeting In... Foundation announces the following meeting: Name: Astronomy and Astrophysics Advisory Committee ( 13883... of astronomy and astrophysics that are of mutual interest and concern to the agencies. Agenda: To...

78 FR 2450 - Astronomy and Astrophysics Advisory Committee; Notice of Meeting

Science.gov (United States)

2013-01-11

... NATIONAL SCIENCE FOUNDATION Astronomy and Astrophysics Advisory Committee; Notice of Meeting In... Foundation announces the following meeting: Name: Astronomy and Astrophysics Advisory Committee ( 13883...) on issues within the field of astronomy and astrophysics that are of mutual interest and concern to...

77 FR 8288 - Astronomy and Astrophysics Advisory Committee; Notice of Meeting

Science.gov (United States)

2012-02-14

... NATIONAL SCIENCE FOUNDATION Astronomy and Astrophysics Advisory Committee; Notice of Meeting In... Foundation announces the following meeting: Name: Astronomy and Astrophysics Advisory Committee ( 13883... of astronomy and astrophysics that are of mutual interest and concern to the agencies. Agenda: To...

OLFAR - Orbiting low frequency antennas for radio astronomy

NARCIS (Netherlands)

Bentum, Marinus Jan

2013-01-01

One of the last unexplored frequency ranges in radio astronomy is the frequency band below 30 MHz. New interesting astronomical science drivers for low frequency radio astronomy have emerged, ranging from studies of the astronomical dark ages, the epoch of reionization, exoplanets, to ultra-high

Making Astronomy Accessible

Science.gov (United States)

Grice, Noreen A.

2011-05-01

A new semester begins, and your students enter the classroom for the first time. You notice a student sitting in a wheelchair or walking with assistance from a cane. Maybe you see a student with a guide dog or carrying a Braille computer. Another student gestures "hello” but then continues hand motions, and you realize the person is actually signing. You wonder why another student is using an electronic device to speak. Think this can't happen in your class? According to the U.S. Census, one out of every five Americans has a disability. And some disabilities, such as autism, dyslexia and arthritis, are considered "invisible” disabilities. This means you have a high probability that one of your students will have a disability. As an astronomy instructor, you have the opportunity to reach a wide variety of learners by using creative teaching strategies. I will share some suggestions on how to make astronomy and your part of the universe more accessible for everyone.

Infrared astronomy

International Nuclear Information System (INIS)

Setti, G.; Fazio, G.

1978-01-01

This volume contains lectures describing the important achievements in infrared astronomy. The topics included are galactic infrared sources and their role in star formation, the nature of the interstellar medium and galactic structure, the interpretation of infrared, optical and radio observations of extra-galactic sources and their role in the origin and structure of the universe, instrumental techniques and a review of future space observations. (C.F.)

First data from X-ray astronomy satellite

International Nuclear Information System (INIS)

Cox, J.

1984-01-01

EXOSAT, the European Space Agency's first x-ray astronomy satellite which was launched last year, has sent back information on x-ray sources. The article briefly discusses the observations made by the satellite concerning Cygnus x-1 and the galactic supernova remnant Cassiopeia A. EXOSAT is the first x-ray astronomy satellite to be operated in a deep space orbit

Resources for Teaching Astronomy in UK Schools

Science.gov (United States)

Roche, Paul; Newsam, Andy; Roberts, Sarah; Mason, Tom; Baruch, John

2012-01-01

This article looks at a selection of resources currently available for use in the teaching of astronomy in UK schools. It is by no means an exhaustive list but it highlights a variety of free resources that can be used in the classroom to help engage students of all ages with astronomy and space science. It also lists several facilities with a…

IAU Astronomy for Equity and Inclusion Working Group

Science.gov (United States)

Ortiz-Gil, A.; García, B.; WG3 of Commission C1 Division C of the IAU

2017-03-01

In this talk we present the aims, goals and activities that have been started by the working group on Astronomy for Equity and Inclusion. This working group is part of Commission 1 ''Astronomy Education and Development'' of Division C ''Education, Outreach and Heritage'' of the International Astronomical Union (IAU). The working group was born with the aim of developing new strategies and resources to promote the access to Astronomy, both at the profesional and outreach levels, for persons with special needs or for those who could be excluded because of race or sexual orientation (among other reasons). It is composed of astronomers affiliated with the IAU and other volunteers who work in astronomy, education and special needs, as well as partner organizations like the IAU Office of Astronomy for Development (OAD), Astronomers without Borders (AWB), the Galileo Teacher Training Program (GTTP) or Universe Awareness (UNAWE). To reach those goals we have started different initiatives which are outlined at the working group’s website, like a repository of resources or the creation of a document about good practices, and the establishment of a tight collaboration with the Working Group about Accessibility of the American Astronomical Society, which was formed recently too.

The sociology of innovation in modern astronomy

International Nuclear Information System (INIS)

Edge, D.

1977-01-01

This paper describes some of the main features of the development of astronomy since 1945, stressing sociological factors, and drawing examples mainly from the history of radio astronomy. Particular attention is given to aspects which appear to distinguish astronomy from other recently-studied sciences - notably, the prevalence of serendipitous discoveries, and the lack of any general resistance from the 'parent' discipline. The work of Kuhn and Hagstrom is used to illuminate these features, and also to indicate how a sociological analysis can be advanced of individual research decisions, and of the nature of disputes within science. Common misconceptions about the nature and scope of sociology are briefly discussed; in particular, it is emphasized that the kind of sociology of science under discussion cannot be normative. (author)

Innovative technology for optical and infrared astronomy

Science.gov (United States)

Cunningham, Colin R.; Evans, Christopher J.; Molster, Frank; Kendrew, Sarah; Kenworthy, Matthew A.; Snik, Frans

2012-09-01

Advances in astronomy are often enabled by adoption of new technology. In some instances this is where the technology has been invented specifically for astronomy, but more usually it is adopted from another scientific or industrial area of application. The adoption of new technology typically occurs via one of two processes. The more usual is incremental progress by a series of small improvements, but occasionally this process is disruptive, where a new technology completely replaces an older one. One of the activities of the OPTICON Key Technology Network over the past few years has been a technology forecasting exercise. Here we report on a recent event which focused on the more radical, potentially disruptive technologies for ground-based, optical and infrared astronomy.

Expanding radio astronomy in Africa

International Nuclear Information System (INIS)

Gaylard, M J

2013-01-01

The Square Kilometre Array (SKA) Organisation announced in May 2012 that its members had agreed on a dual site solution for the SKA [1]. South Africa's bid for hosting the SKA has caused a ramp up of radio astronomy in Africa. To develop technology towards the SKA, the South African SKA Project (SKA SA) built a protoype radio telescope in 2007, followed in 2010 the seven antenna Karoo Array Telescope (KAT-7). Next is the 64 antenna MeerKAT, which will merge into SKA Phase 1 in Africa. As SKA Phase 2 is intended to add a high resolution capability with baselines out to 3000 km, the SKA SA brought in partner countries in Africa to host outstations. South Africa has been working with the partners to build capacity to operate the SKA and to benefit from it. The SA Department of Science and Technology (DST) developed a proposal to establish radio telescopes in the partner countries to provide hands-on learning and a capability for Very Long Baseline Interferometry (VLBI) research. Redundant 30 m class satellite antennas are being incorporated in this project.

Adjustable Grazing Incidence X-ray Optics with 0.5 Arc Second Resolution

Science.gov (United States)

Reid, Paul

We seek to develop adjustable grazing incidence optics for x-ray astronomy. The goal of this development is thin, lightweight mirrors with angular resolution of 0.5 arc seconds, comparable to the Chandra X-ray Observatory. The new mirror design consists of thin segments of a Wolter-I grazing incidence mirror, with piezo-electric material deposited directly on the back surface of the mirror. Depositing a pattern of independently addressable electrodes on top of the piezoelectric material produces an array of independent piezo cells. Energizing a particular cell introduces a localized deformation in the mirror without the need for a reaction structure. By applying the appropriate voltage to the piezo cells, it is possible to correct mirror figure errors that result from mirror fabrication, gravity release, mounting, and thermal effects. Because the thin mirrors segments are lightweight, they can be densely nested to produce collecting area thirty times that of Chandra, on an affordably priced mission. This Supporting Technology program is a follow-on to an existing APRA program. In the existing program we demonstrated the first successful deposition of piezoelectric material on thermally formed glass substrates. We showed that the localized deformations produced by the piezo cells match finite element predictions, and the piezo cell adjustment range meets requirements necessary to achieve the desired figure correction. We have also shown through simulation that representative mirror figure errors can be corrected via modeled influence functions to achieve 0.5 arc sec imaging performance. This provides a firm foundation on which to develop further the technology. We will continue to optimize the deposition of thin piezoelectric films onto thermally formed glass and electroplated metal mirror segments to improve yield and manufacturability. We will deposit piezoelectric material onto conical mirror segments and demonstrate figure correction in agreement with prediction

Natural roller bearing fault detection by angular measurement of true instantaneous angular speed

Science.gov (United States)

Renaudin, L.; Bonnardot, F.; Musy, O.; Doray, J. B.; Rémond, D.

2010-10-01

The challenge in many production activities involving large mechanical devices like power transmissions consists in reducing the machine downtime, in managing repairs and in improving operating time. Most online monitoring systems are based on conventional vibration measurement devices for gear transmissions or bearings in mechanical components. In this paper, we propose an alternative way of bearing condition monitoring based on the instantaneous angular speed measurement. By the help of a large experimental investigation on two different applications, we prove that localized faults like pitting in bearing generate small angular speed fluctuations which are measurable with optical or magnetic encoders. We also emphasize the benefits of measuring instantaneous angular speed with the pulse timing method through an implicit angular sampling which ensures insensitivity to speed fluctuation. A wide range of operating conditions have been tested for the two applications with varying speed, load, external excitations, gear ratio, etc. The tests performed on an automotive gearbox or on actual operating vehicle wheels also establish the robustness of the proposed methodology. By the means of a conventional Fourier transform, angular frequency channels kinematically related to the fault periodicity show significant magnitude differences related to the damage severity. Sideband effects are evidently seen when the fault is located on rotating parts of the bearing due to load modulation. Additionally, slip effects are also suspected to be at the origin of enlargement of spectrum peaks in the case of double row bearings loaded in a pure radial direction.

Training in Astronomy for Physics Students J. H. Fan1,2

Indian Academy of Sciences (India)

2Astronomy Science and Technology Research Laboratory, Department of Education of Guangdong Province, Guangzhou 510006, ... to astronomy training for physics students. More and more students are ... We, astronomy staff give popular science talks for undergraduate students, middle school students, primary school ...

Angular momentum from tidal torques

International Nuclear Information System (INIS)

Barnes, J.; Efstathiou, G.; Cambridge Univ., England)

1987-01-01

The origin of the angular momentum of bound objects in large N-body simulations is studied using three sets of models. One model with white-noise initial conditions is analyzed as well as two in which the initial conditions have more power on large scales, as predicted in models with cold dark matter. The growth and distribution of angular momentum in individual objects is studied and it is found that the specific angular momentum distribution of bound clumps increases in a near linear fashion with radius while the orientation of the angular momentum in the inner high-density regions is often poorly correlated with that of the outer parts. It is also found that the dimensionless spin parameter is insensitive to the initial perturbation spectrum and has a median value of about 0.05. 61 references

Transverse and longitudinal angular momenta of light

Energy Technology Data Exchange (ETDEWEB)

Bliokh, Konstantin Y., E-mail: k.bliokh@gmail.com [Center for Emergent Matter Science, RIKEN, Wako-shi, Saitama 351-0198 (Japan); Nonlinear Physics Centre, RSPhysE, The Australian National University, Canberra, ACT 0200 (Australia); Nori, Franco [Center for Emergent Matter Science, RIKEN, Wako-shi, Saitama 351-0198 (Japan); Physics Department, University of Michigan, Ann Arbor, MI 48109-1040 (United States)

2015-08-26

We review basic physics and novel types of optical angular momentum. We start with a theoretical overview of momentum and angular momentum properties of generic optical fields, and discuss methods for their experimental measurements. In particular, we describe the well-known longitudinal (i.e., aligned with the mean momentum) spin and orbital angular momenta in polarized vortex beams. Then, we focus on the transverse (i.e., orthogonal to the mean momentum) spin and orbital angular momenta, which were recently actively discussed in theory and observed in experiments. First, the recently-discovered transverse spin  angular momenta appear in various structured fields: evanescent waves, interference fields, and focused beams. We show that there are several kinds of transverse spin angular momentum, which differ strongly in their origins and physical properties. We describe extraordinary features of the transverse optical spins and overview recent experiments. In particular, the helicity-independent transverse spin inherent in edge evanescent waves offers robust spin–direction coupling at optical interfaces (the quantum spin Hall effect of light). Second, we overview the transverse orbital angular momenta of light, which can be both extrinsic and intrinsic. These two types of the transverse orbital angular momentum are produced by spatial shifts of the optical beams (e.g., in the spin Hall effect of light) and their Lorentz boosts, respectively. Our review is underpinned by a unified theory of the angular momentum of light based on the canonical momentum and spin densities, which avoids complications associated with the separation of spin and orbital angular momenta in the Poynting picture. It allows us to construct a comprehensive classification of all known optical angular momenta based on their key parameters and main physical properties.

Journal of Astrophysics and Astronomy | Indian Academy of Sciences

Indian Academy of Sciences (India)

2016-01-27

Jan 27, 2016 ... Astronomy Education Project for Guangdong High Schools ... Astronomy education; high school; science popularization. ... This means that each accepted article is being published immediately online with DOI and article ...

Fission Fragment Angular Distributions in the $^{234}$U(n,f) and $^{236}$U(n,f) reactions

CERN Multimedia

We propose to measure the fission fragment angular distribution (FFAD) of the $^{234}$U(n,f) and $^{236}$U (n,f) reactions with the PPAC detection setup used in previous n_TOF-14 experiment. This experiment would take advantage of the high resolution of the n_TOF facility to investigate the FFAD behaviour in the pronounced vibrational resonances that have been observed between 0.1 and 2 MeV for the thorium cycle isotopes. In addition, the angular distribution of these isotopes will be measured for the first time beyond 14 MeV. Furthermore, the experiment will also provide the fission cross section with reduced statistical uncertainty, extending the $^{236}$U(n,f) data up to 1 GeV

The Importance of Site Selection for Radio Astronomy

International Nuclear Information System (INIS)

Umar, Roslan; Abidin, Zamri Zainal; Ibrahim, Zainol Abidin

2014-01-01

Radio sources are very weak since this object travel very far from outer space. Radio astronomy studies are limited due to radio frequency interference (RFI) that is made by man. If the harassment is not stopped, it will provide critical problems in their radio astronomy scientists research. The purpose of this study is to provide RFI map Peninsular Malaysia with a minimum mapping techniques RFI interference. RFI mapping technique using GIS is proposed as a tool in mapping techniques. Decision-making process for the selection requires gathering information from a variety of parameters. These factors affecting the selection process are also taken account. In this study, various factors or parameters involved such as availability of telecommunications transmission (including radio and television), rainfall, water line and human activity. This study will benefit radio astronomy research especially in the RFI profile in Malaysia. Keywords: Radio Astronomy, Radio Frequency Interference (RFI), RFI mapping technique : GIS

Astronomy Education Programs at the Smithsonian National Air and Space Museum

Science.gov (United States)

Nagy, Katie; de Messieres, G.; Edson, S.

2014-01-01

Astronomy educators present the range of astronomy education programming available at the National Air and Space Museum, including the following. In the Phoebe Waterman Haas Public Observatory, visitors use telescopes and other scientific equipment to observe and discuss the Sun, Venus, and other celestial sights in an unstructured, inquiry-based environment. At Discovery Stations throughout the Museum, staff and volunteers engage visitors in hands-on exploration of a wide range of artifacts and teaching materials. Astronomy-related Discovery Stations include Cosmic Survey, an exploration of gravitational lensing using a rubber sheet, spectroscopy using discharge tubes, and several others. Astronomy lectures in the planetarium or IMAX theater, featuring researchers as the speakers, include a full evening of activities: a custom pre-lecture Discovery Station, a handout to help visitors explore the topic in more depth, and evening stargazing at the Public Observatory. Astronomy educators present planetarium shows, including star tours and explorations of recent science news. During Astronomy Chat, an astronomy researcher engages visitors in an informal conversation about science. The goal is to make the public feel welcome in the environment of professional research and to give busy scientists a convenient outreach opportunity. Astronomy educators also recruit, train, and coordinate a corps of volunteers who contribute their efforts to the programming above. The volunteer program has grown significantly since the Public Observatory was built in 2009.

Astronomy and astrophysics in the new millennium: Panel reports

National Research Council Canada - National Science Library

Astronomy and Astrophysics Survey Committee, Board on Physics and Astronomy, Space Studies Board, National Research Council

2001-01-01

In preparing the report, Astronomy and Astrophysics in the New Millenium , the AASC made use of a series of panel reports that address various aspects of ground- and space-based astronomy and astrophysic...

Critical Issues in the Philosophy of Astronomy and Cosmology

Science.gov (United States)

Dick, Steven J.

2016-01-01

Although the philosophy of science and of specific sciences such as physics, chemistry, and biology are well-developed fields with their own books and journals, the philosophy of astronomy and cosmology have received little systematic attention. At least six categories of problems may be identified in the astronomical context: 1) the nature of reasoning, including the roles of observation, theory, simulation, and analogy, as well as the limits of reasoning, starkly evident in the anthropic principle, fine-tuning, and multiverse controversies; 2) the often problematic nature of evidence and inference, especially since the objects of astronomical interest are for the most part beyond experiment and experience;3) the influence of metaphysical preconceptions and non-scientific worldviews on astronomy, evidenced, for example in the work of Arthur S. Eddington and many other astronomers; 4) the epistemological status of astronomy and its central concepts, including the process of discovery, the problems of classification, and the pitfalls of definition (as in planets); 5) the role of technology in shaping the discipline of astronomy and our view of the universe; and 6) the mutual interactions of astronomy and cosmology with society over time. Discussion of these issues should draw heavily on the history of astronomy as well as current research, and may reveal an evolution in approaches, techniques, and goals, perhaps with policy relevance. This endeavor should also utilize and synergize approaches and results from philosophy of science and of related sciences such as physics (e.g. discussions on the nature of space and time). Philosophers, historians and scientists should join this new endeavor. A Journal of the Philosophy of Astronomy and Cosmology (JPAC) could help focus attention on their studies.

The solid state track detectors for α-particles angular distribution measurements