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1.
Kulinder Pal Singh 《Resonance》2005,10(7):8-20
The excellent X-ray images produced by X-ray telescopes require the use of detectors with imaging capability at the focal
plane of the telescopes. In this concluding part of the article on experimental techniques in X-ray astronomy, I describe
many X-ray detectors that have been used over the years. These can broadly be classified into two physical types: non-dispersive
and dispersive. Traditionally the simple non-dispersive types have been used extensively in X-ray astronomy. The advancement
of solid state technologies, cryogenics, and the quality of X-ray imaging has led to many new detectors of both types. Both
the traditional and the new types of detectors are described briefly here with emphasis on principles and some technical details.
Kulinder Pal Singh is in the Department of Astronomy and Astrophysics of the Tata Institute of Fundamental Research, Mumbai.
His primary fields of research are X-ray studies of hot plasmas in stars, supernova remnants, galaxies, intergalactic medium
in clusters of galaxies, active galactic nuclei, cataclysmic variables and X-ray binaries. He is leading the development of
a soft X-ray imaging telescope for the ASTROSAT mission to be launched by India in 2007–2008.
Part 1. Imaging Telescopes,Resonance, Vol. 10, No. 5, pp. 15–23, 2005. 相似文献
2.
Biman Nath 《Resonance》2009,14(3):226-235
Soon after the discovery that we live in a separate galaxy and that there are many other galaxies in the universe, Hubble
designed a classification scheme of galaxies based on their appearances. It was such a robust scheme that it continues to
be one of the basic tools of modern astronomy, and motivates astronomers to look for connections between different types of
galaxies. 相似文献
3.
4.
The program at the MIT Haystack Observatory has added a new opportunity for students as part of our overall national effort to encourage research by undergraduates. Radio astronomy complements other branches of astronomy, augments science education broadly, and serves to promote interdisciplinary research and education. In the past 2 years, we have conducted a successful pilot program to develop and test a program that facilitates the linking of undergraduate research and education through radio astronomy. As a result of this effort, a small radio telescope has been developed and can be used as a hands-on introduction to radio astronomical techniques and instrument calibration. The telescope is presently being commercialized so that it can be purchased as a low-cost kit for assembly. Remote access to the Haystack 37-m antenna has made it possible for students nationwide to access a research grade facility and we invite faculty everywhere who are interested in this possibility to use our facility. Undergraduate students can participate in the exciting world of research by performing experiments with the telescope. Radio astronomy materials for faculty, students, and interested amateurs have been developed are posted on our web site (http://www.haystack.mit.edu). The materials will continue to be upgraded and enhanced, and the contributions from participating teachers and students nationwide will be added to the project files. We hope to make this not only a resource for someone using our facility but also for the community in general.We are now bringing the Haystack telescopes and radio astronomy to the broad undergraduate community. Based on our pilot experiences, we envision students everywhere being able to exploit the opportunity to strengthen their education through practical research using radio astronomy. 相似文献
5.
Philip M. Sadler Roy R. Gould P. Steven Leiker Paul R. A. Antonucci Robert Kimberk Freeman S. Deutsch Beth Hoffman Mary Dussault Adam Contos Kenneth Brecher Linda French 《Journal of Science Education and Technology》2001,10(1):39-55
Many students have a deep interest in astronomy, but a limited opportunity to use telescopes to explore the heavens. The MicroObservatory Network of automated telescopes is designed to provide access to classroom teachers who wish their students to conduct projects over the World Wide Web. The intuitive interface makes it easy for even 10-year-olds to take pictures. Telescopes can be remotely pointed and focused: filters, field of view, and exposure times can be changed easily. Images are archived at the website, along with sample challenges and a user bulletin board, all of which encourage collaboration among schools. Wide geographic separation of instruments provides access to distant night skies during local daytime. Since first light in 1995, we have learned much about remote troubleshooting, designing for unattended use, and for acquiring the kinds of images that students desire. This network can be scaled up from its present capability of 240,000 images each year to provide telescope access for all US students with an interest in astronomy. Our WWW address is http://mo-www.harvard.edu/MicroObservatory/ 相似文献
6.
The dynamics of the Sun-Earth-Moon system is discussed with special attention to the effects of Sun’s perturbations on the
Moon’s orbit around the Earth. Important secular effects are the regression of the nodes, the advance of the perigee and the
increase in the Moon’s mean longitude. We discuss the relationship of the first with the occurrence of eclipses, the second
with the fluctuations in the moon’s synodic period, and the third with the slowing down of the Earth’s rotation due to tidal
friction. The Sun-Earth-Moon system is compared with other triple celestial systems with regard to the intensity of tidal
effects.
S M Alladin is a retired professor of Astronomy, Osmania University, Hyderabad. He specialized in dynamical astronomy and
did research on the dynamics of colliding and merging galaxies. He is interested in the interaction between religion and science.
G M Ballabh is a retired professor of Astronomy, Osmania University, Hyderabad. His field of research includes dynamical astronomy
and positional astronomy. At present he is the Chairman of the Standing Advisory Committee for the Positional Astronomy Centre,
Kolkata 相似文献
7.
Electromagnetic radiation is all around us, and essential for the survival of all lifeforms. It provides valuable information
about the physical world around us, feeds us by providing energy to plants, allows us to maintain human metabolism, and cures
us of various diseases. This article deals with the various properties of electromagnetic radiation, its sources and detectors,
its nature, and its uses. A brief discussion on the absorption spectrum of the Earth’s atmosphere and the atmospheric windows,
and celestial objects seen through optical and radio telescopes is also provided. 相似文献
8.
When two galaxies approach each other, we can witness the effects of the tidal forces on a gigantic scale. Peculiar features
like galactic bridges and galactic tails may form, or the two galaxies may even merge into each other and form a single system.
Merger of two spiral galaxies leads to the formation of an elliptical galaxy. The interaction of gas during such galaxy encounters
triggers star formation and activity of the nucleus. It is generally being accepted that galaxy interactions and mergers play
a vital role in galactic evolution.
S M Alladin is a retired Professor of Astronomy, Osmania University, Hyderabad. He specialized in dynamical astronomy and
did research on dynamics of colliding and merging galaxies. He is also interested in interaction between religion and science.
S N Hasan is an Assistant Professor of Astronomy, Osmania University, Hyderabad. His field of specialization is celestial
mechanics. His research interests include the three body problem, stellar and galactic dynamics. 相似文献
9.
Rajaram Nityananda 《Resonance》2017,22(7):645-657
Stars, other than the Sun, appear to our unaided eyes as points of light. Large telescopes show an image whose size is dictated by refractive index irregularities in the Earth’s atmosphere. The size of this blurring is much greater than that of the star, and hence it is difficult to measure the stellar size. Fizeau showed how one might overcome this limitation using the two-slit interference technique. It was Michelson who carried out this programme and made the first direct measurement of the giant star Betelguse in the constellation of Orion. His value for the angular diameter, 47 milliarcseconds or 2.6×10?7 radians, was completely confirmed by later work following his methods. The key concept introduced was ‘fringe visibility’, which turned out to be very fruitful in the later development of optics as well as astronomy. 相似文献
10.
In Part I1 of this article we learnt that there are compelling evidences from dynamics of spiral galaxies, like our own, that there must be non-luminous matter in them. In this second part we will see that even clusters of galaxies must harbour dark matter. As if this was not enough, it turns out that if our knowledge of the universe is not completely wrong, then the universe as a whole has to contain dark matter and that it must be of some exotic type. 相似文献
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12.
In Part I of this article we learnt that there are compelling evidences from dynamics of spiral galaxies, like our own, that
there must be non-luminous matter in them. In this second part we will see that even clusters of galaxies must harbour dark
matter. As if this was not enough, it turns out that if our knowledge of the universe is not completely wrong, then the universe
as a whole has to contain dark matter and that it must be of some exotic type. 相似文献
13.
The purpose of the Department of Physics's close association with the Gothard Observatory is to provide a foundation in basic astronomy and astrophysics during 3 semesters in Berzsenyi Daniel Teacher Training College for future Hungarian Elementary School teachers who will teach pupils to age 14 years. The courses of lectures include: Solar System, Sun, Stars, Stellar Interiors and Atmospheres, Astronomical Techniques, Extragalactic Astronomy, Cosmology. Students have outstanding opportunities to learn and to apply in their research the development of instrumentation, and the techniques of observation with telescopes. Excellent modern computing facilities for support of data analysis and theoretical work are available at Gothard Observatory. Library facilities contain a wealth of astronomical reference materials. Students have direct access to many facilities of the Department and Observatory. 相似文献
14.
Amartya Kumar Dutta 《Resonance》2006,11(3):51-68
Āryabhata (born 476 CE) is regarded as a pioneer of mathematical astronomy in ancient India. In this three-part article, I
shall discuss one important contribution of Āryabhata in astronomy involving the least technical background —the principle
of axial rotation (Part 1) and computations on the sidereal day (Part 2). Portions of 4 verses, pertaining to Earth’s rotation,
from his famous treatise Āryabhatīya will be quoted. In Part 3, I shall give a brief historical account on the concept of
axial rotation of Earth. 相似文献
15.
Anja Thorsten 《Educational Action Research》2017,25(1):140-154
The purpose of this article is to discuss and describe how a clinical research method can be used to generate knowledge about teaching and learning. This will be addressed from a teacher researcher’s perspective, taking a conducted Learning Study as the departure. Learning Study is an interventionist, iterative and collaborative research approach, focusing on the teaching of an object of learning. The actual study was conducted by a teacher researcher leading a teacher research team in a study about story-writing in primary school. The research process and the results are discussed using four areas that are described as dichotomies by Labaree (Labaree, D.F. 2003. “The Peculiar Problems of Preparing Educational Researchers.” Educational Researcher 32 (4): 13–22). Labaree states that teacher researchers need to go from being normative, experimental, personal and particular to being analytical, theoretical, intellectual and universal. By using examples from the Learning Study, I argue that these areas do not have to be seen as dichotomies; instead they can be combined and intertwined. Thus, in a Learning Study, elements from both the teaching practice and the academic practice matter, thus enhancing the possibility that results are useful for practitioners. 相似文献
16.
Esther M. Bergman Judith M. Sieben Ida Smailbegovic Anique B.H. de Bruin Albert J.J.A. Scherpbier Cees P.M. van der Vleuten 《Anatomical sciences education》2013,6(2):114-124
Anatomy education often consists of a combination of lectures and laboratory sessions, the latter frequently including surface anatomy. Studying surface anatomy enables students to elaborate on their knowledge of the cadaver's static anatomy by enabling the visualization of structures, especially those of the musculoskeletal system, move and function in a living human being. A recent development in teaching methods for surface anatomy is body painting, which several studies suggest increases both student motivation and knowledge acquisition. This article focuses on a teaching approach and is a translational contribution to existing literature. In line with best evidence medical education, the aim of this article is twofold: to briefly inform teachers about constructivist learning theory and elaborate on the principles of constructive, collaborative, contextual, and self‐directed learning; and to provide teachers with an example of how to implement these learning principles to change the approach to teaching surface anatomy. Student evaluations of this new approach demonstrate that the application of these learning principles leads to higher student satisfaction. However, research suggests that even better results could be achieved by further adjustments in the application of contextual and self‐directed learning principles. Successful implementation and guidance of peer physical examination is crucial for the described approach, but research shows that other options, like using life models, seem to work equally well. Future research on surface anatomy should focus on increasing the students' ability to apply anatomical knowledge and defining the setting in which certain teaching methods and approaches have a positive effect. Anat Sci Educ 6: 114–124. © 2012 American Association of Anatomists. 相似文献
17.
Keating Thomas Barnett Michael Barab Sasha A. Hay Kenneth E. 《Journal of Science Education and Technology》2002,11(3):261-275
The Virtual Solar System (VSS) course described in this paper is one of the first attempts to integrate three-dimensional (3D) computer modeling as a central component of an introductory undergraduate astronomy course. Specifically, this study assessed the changes in undergraduate university students' understanding of astronomy concepts as a result of participating in an experimental introductory astronomy course in which the students constructed 3D models of different astronomical phenomena. In this study, we examined students' conceptual understanding concerning three foundational astronomical phenomena: the causes of lunar and solar eclipses, the causes of the Moon's phases, and the reasons for the Earth's seasons. Student interviews conducted prior to the course identified a range of student alternative conceptions previously identified in the literature regarding the dynamics and mechanics of the Solar System. A previously undocumented alternative conception to explain lunar eclipses is identified in this paper. The interviews were repeated at the end of the course in order to quantitatively and qualitatively assess any changes in student conceptual understanding. Generally, the results of this study revealed that 3D computer modeling can be a powerful tool in supporting student conceptualization of abstract scientific phenomena. Specifically, 3D computer modeling afforded students the ability to visualize abstract 3D concepts such as the line of nodes and transform them into conceptual tools, which in turn, supported the development of scientifically sophisticated conceptual understandings of many basic astronomical topics. However, there were instances where students' conceptual understanding was incomplete and frequently hybridized with their existing conceptions. These findings have significant bearing on when and in what domains 3D computer modeling can be used to support student conceptual understanding of astronomy concepts. 相似文献
18.
E. Walsh G. Dall'Alba J. Bowden E. Martin F. Marton G. Masters P. Ramsden A. Stephanou 《科学教学研究杂志》1993,30(9):1133-1148
It is important that students of physics develop both quantitative and qualitative understanding of physical concepts and principles. Although accuracy and reliability in solving quantitative problems is necessary, a qualitative understanding is required in applying concepts and principles to new problems and in real-life situations. If students are not able to understand what underlies quantitative problem-solving procedures nor interpret the solution in physical terms, it is questionable whether they have developed an adequate understanding of physics. The research reported here is part of a larger phenomenographic study that is concerned with the assessment of physics students' understanding of some basic concepts and principles in kinematics. In this article students' understanding of the concept of relative speed is described. A variety of ways of understanding relative speed and of viewing a problem that dealt with this concept were uncovered. The results are used to suggest ways for teachers to proceed in assisting students to enhance their understanding of this concept. The teaching principles outlined concern both teaching relative speed, in particular, and teaching scientific concepts and principles, more generally. 相似文献
19.
Flexible Learning Environments: Leveraging the Affordances of Flexible Delivery and Flexible Learning 总被引：1，自引：0，他引：1
Janette R. Hill 《Innovative Higher Education》2006,31(3):187-197
The purpose of this article is to explore the key features of flexible learning environments (FLEs). Key principles associated with FLEs are explained. Underlying tenets and support mechanisms necessary for the implementation of FLEs are described. Similarities and differences in traditional learning and FLEs are explored. Finally, strategies and techniques for becoming a successful learner and facilitator in FLEs are presented.Initial ideas for this paper were generated after viewing a presentation created by Marie Jasinski, MindMedia, Douglas Mawson Institute, Adelaide, Australia ().Janette Hill is an Associate Professor in the Department of Educational Psychology and Instructional Technology at The University of Georgia, Athens. She received her Ph.D. from The Florida State University in Instructional Systems. Dr. Hill's research focuses on online learning with adults, specifically exploring issues related to building community and connections with others in virtual environments. Dr. Hill can be reached at janette@uga.edu. 相似文献
20.
《Journal of moral education》2012,41(3):174-181
Abstract In this article, which is the first of two to examine the ideas of R. S. Peters on moral education, consideration is given to his justificatory arguments found in Ethics and Education. Here he employs presupposition arguments to show to what anyone engaging in moral discourse is committed. The result is a group of procedural principles which are recommended to be employed in moral education. This article is an attempt to examine the presupposition arguments Peters employs, to comment on the procedural principles he believes are presupposed, and to consider the strength of the presupposition argument. My conclusion is that Peters's arguments fail to establish the conclusion he arrives at, and that any gains from the form of argument he uses are hollow. 相似文献