With a great deal of humility I attempt in the following to recall important events in my life and in my scientific career of more than five decades. I am not through yet. I continue to do research though, I admit, not with the energy and fervor I once had. Still, I hope to contribute to science in meaningful ways. 相似文献
After twelve years have past since the discovery of the first high-frequency quasi-periodic oscillation in Sco X-1, an enormous progress has been made on the observational side and on the field of data analysis. Equal amount of effort has been devoted also to the theoretical aspect of the QPO problem. However, so far no model is able to sufficiently fully explain the mechanism of QPO production. There are two aspects: the question of the QPO origin; and the question of its modulation. In this article, I am focusing solely on the second issue – I discuss ways of how the outgoing flux can be modulated at a level sufficient to match the observational rms amplitudes. Some more space is devoted to my own work in the field. 相似文献
I returned to China from the United Kingdom in 1953,then worked in Purple Mountain Observatory.It was the early days of new China.The elder generation of astronomers was undertaking an effort of "repairing broken and filling defect" during those post-war years,and started planning and laying the foundation of modern astronomy.Under their leadership,I started a journey of astronomy whose main task was construction.The journey has been full of twists and turns.As a result of the "Great Leap Forward" in 1958 and the 1966 launch of the decade-long "Cultural Revolution" period,the situation of construction in astronomy was similar to that in other sciences,suffering bad effects.Not until the "Reform and Opening up" period after those events was construction able to continue,and various disciplines and international connections began to open.A "passage" had gradually developed.In this new circumstance,I kept pursuing the pioneers to explore a forward direction.Looking back today,this journey has been three periods of a four generation relay.This article is divided into three sections that describe my research work in these times that I recall:(1) Looking back at the beginning of the return and tracing the footprints of the founders.(2) Recalling my radio astronomy tour.(3) Retrospection and expectation of LAMOST. 相似文献
This memoir reviews my academic career in solar physics for 60 years, including my research on non-LTE modeling, white-light flares, and small-scale solar activities. Through this narrative, the reader can catch a glimpse of the development of solar physics research in mainland China from scratch. In the end, some prospects for future development are given. 相似文献
Abstract— The science of nucleosynthesis was substantially inspired by chemical analyses of meteorites. As if in repayment, that theory now imbues meteoritics with enlarged meaning. I recount the emergence of four great issues for nucleosynthesis—issues that received decades of my own attention; and I describe unexpected abundance patterns within meteorites that were suggested by the resolution of those issues. The latter have altered the information content of meteoritic science. The issues are: 1. a quantitative s-process theory 2. cosmoradiogenic chronology 3. explosive nucleosynthesis and gamma-ray astronomy 4. cosmic chemical memory Starting from historical origins for each issue, I comment upon both the broad cultural canvas in which they lie and my own work in their establishment. Examples of predicted (or rationalized) meteoritic measurements illustrate our surprised delight at the expansion of the range and power of meteoritic science. 相似文献
Soft X-ray photographs of the Sun taken at O vii 21.6 Å and in a spectral band ranging from 13.2 to 22.1 Å have been analysed in order to establish spatially resolved maps of temperature and emission measure for several active regions in the corona. The photographs were taken on 11 March, 1971, and on 2 March, 1972, with Fresnel zone plate cameras which were flown on ESRO and NRL sounding rockets.In Part I of this paper we first deal with those aspects of the instrumentation which are important for setting up a suitable image analysis procedure. We discuss the characteristics of the wavelength dependent image formation by zone plates combined with absorption filters. Results of the calibration of the X-ray film are given. Then we describe a specific iterative data reduction procedure and finally present the resulting maps of temperature and emission measure for a selected active region. In Part II corresponding results for further active regions will be given and discussed. 相似文献
May I first express my warmest thanks to the organizers of the Conference for having invited me to present a brief bibliographic report on the great astronomer F. W. Bessel. You have given me a welcome opportunity to express an appreciation of Bessel's work which has marked the beginning of research on the motion of stars and which was pioneer work on astrometric binaries and on the determination of stellar distances. Bessel has established the first celestial coordinate system which approximates an inertial system, and my colleagues and I at Heidelberg in establishing an improved fundamental reference system, the FK5, have had to review again some of Bessel's pioneer contributions to this field, and such contributions shall be mentioned later. My talk shall be divided into the following parts: (1) Bessel's course of life and family; (2) Education in astronomy in Bremen; (3) Fundamenta Astronomiae; (4) Fundamental observations at the Königsberg Observatory (or according to S. Newcomb (1906): the German School of Astrometry); (5) 61 Cygni; (6) Bibliography of Bessel's original works.Communication presented at the International Conference on Astrometric Binaries, held on 13–15 June, 1984, at the Remeis-Sternwarte Bamberg, Germany, to commemorate the 200th anniversary of the birth of Friedrich Wilhelm Bessel (1784–1846). 相似文献
In this interview, William Hartmann (Bill, Fig. 1 ) describes how he was inspired as a teenager by a map of the Moon in an encyclopedia and by the paintings by Chesley Bonestell. Through the amateur journal “Strolling Astronomer,” he shared his interests with other teenagers who became lifelong colleagues. At college, he participated in Project Moonwatch, observing early artificial satellites. In graduate school, under Gerard Kuiper, Bill discovered Mare Orientale and other large concentric lunar basin structures. In the 1960s and 1970s, he used crater densities to study surface ages and erosive/depositional effects, predicted the approximately 3.6 Gyr ages of the lunar maria before the Apollo samples, discovered the intense pre‐mare lunar bombardment, deduced the youthful Martian volcanism as part of the Mariner 9 team, and proposed (with Don Davis) the giant impact model for lunar origin. In 1972, he helped found (what is now) the Planetary Science Institute. From the late 1970s to early 1990s, Bill worked mostly with Dale Cruikshank and Dave Tholen at Mauna Kea Observatory, helping to break down the Victorian paradigm that separated comets and asteroids, and determining the approximately 4% albedo of comet nuclei. Most recently, Bill has worked with the imaging teams for several additional Mars missions. He has written three college textbooks and, since the 1970s, after painting illustrations for his textbooks, has devoted part of his time to painting, having had several exhibitions. He has also published two novels. Bill Hartmann won the 2010 Barringer Award for impact studies and the first Carl Sagan Award for outreach in 1997. Figure 1 Open in figure viewer PowerPoint William K. Hartmann taken 2010 Aug 2 (Photo: Gayle Hartmann).
DS
Bill thank you very much for doing this. I would like to start with a very general question. What is the one incident in your life above all others that has determined the nature of your career?
WKH
I would say that what initially stirred my excitement for this topic were the books I stumbled across as a teenager. One event I recall was that my brother, who was 8 years older than I was, had a young person's encyclopedia called the Book of Knowledge. One day I was looking at that book and there was this map of the Moon. Craters, mountains, plains, all sorts of features. That blew me away. The concept that there was this other land, not just a shining thing in the sky, but a geological body, a new geographical place. There was also a book by Willy Ley and Chesley Bonestell, Conquest of Space, which had all these marvelous paintings by Bonestell, visualizing what it was like on other planets. It came out in 1949. I am fond of my copy of that book because my father somehow managed to get Willy Ley, a German expatriate colleague of von Braun's, a writer and popularizer for space, to come to our town and give a talk and autograph my book. Many years later I met Chesley Bonestell and got him to autograph the book. There are not very many copies of that book with the signatures of both authors! The paintings gave me a real desire to want to know what it would be like on other worlds.
This article is a brief history of my life from childhood and describes how I became interested in astronomy. Starting from researches using radiative transfer as a main tool,I gradually expanded my research field to hydrodynamics(particularly convection,turbulence,pulsation,waves and helioseismology),magnetohydrodynamics and chaotic systems. My recent interest is to develop a sustainable society using solar energy. 相似文献
Gamma-ray burst observations performed by LASL began with the identification and initial report of the phenomenon from data acquired by the Vela satellites. The Vela instruments have recorded responses to 73 gamma-ray bursts over a ten-year interval, and are continuing to contribute toward these observations. Similar instrumentation was included aboard the NRL SOLRAD 11 spacecraft. These performed well but suffered an early demise. Recently, the LASL gamma-ray burst astronomy program has been enhanced through the implementation of experiments aboard the Pioneer Venus Orbiter and ISEE-C spacecraft. Both of these experiments are continuing to contribute data vital to trigonometric directional analyses.Paper presented at the Symposium on Cosmic Gamma-Ray Bursts, held at Toulouse, France, 26–29 November, 1979. 相似文献
I had the privilege, many years ago, to be supervised by Alfonso Cavaliere in my Master thesis work. I remember the great
patience and enthusiasm with which, in a warm summer day, he presented to me a score of exciting astrophysical problems. We
finally determined to study the relationship of QSOs and BL Lacs—then considered rather exotic object—with normal galaxies.
In the years I have continued on this line of research, reacting far too slowly to the wealth of new ideas that Alfonso has
been continuously injecting in our conversations. As examples I will report two recent results on the chemical abundances
of QSO host galaxies and on the space density of high-z QSOs, which are closely related to our shared interest on AGN. 相似文献
This invited memoire describes my fortunate life, which has been enriched by meeting many wonderful people. The story starts at home and university, and continues with accounts of St Andrews and trips to the USA, together with musings on the book Solar MHD. The nature and results of collaborations with key people from abroad and with students is mentioned at length. Finally, other important aspects of my life are mentioned briefly before wrapping up. 相似文献
Beginning with his student days at school and college, the author describes his training at Cambridge with special emphasis on his mentor Fred Hoyle. His early experience of participating in a controversy at Cambridge played a major role in giving him the confidence to defend his scientific ideas. All through his later life he chose areas that were not part of mainstream research. These included the steady state theory and later the quasi steady state cosmology, action at a distance, noncosmological redshifts, quantum conformal cosmology, etc. After being a founding member of the Institute of Theoretical Astronomy(IOTA) at Cambridge, the author joined the Tata Institute of Fundamental Research(TIFR) in Mumbai and later moved to Pune to set up the Inter-University Centre for Astronomy and Astrophysics(IUCAA). He briefly reviews his own work and ends by pointing out the difficulties a non-conformist scientist faces in his professional life. In the conclusion, he mentions his interests in science popularization and science fiction for which he has won awards and appreciation, including UNESCO’s Kalinga Prize. 相似文献
This paper considers the discoveries that have appreciably changed our understanding of the physics of solar flares. I identify a total of 42 discoveries from all disciplines, ranging from Galileo's initial observation of faculae to the recent discovery of strong limb brightening in 10-MeV γ-radiation. The rate of discovery increased dramatically over the past four decades as new observational tools became available. My assessment of significance suggests that recent discoveries - though more numerous - are individually less significant; perhaps this is because the minor early discoveries tend to be taken for granted. In spite of the many facets of flare physics that have been explained or at least well-described, many fundamental questions remain unresolved.
Following the kind invitation of Prof. Kopal, I am going to refer at this Conference on current work carried out by the IAU Commission 26, after having circulated a letter to all members to collect recent information at various places. I am grateful to those who replied in time for this report, which will also contain some personal considerations.Communication presented at the International Conference on Astrometric Binaries, held on 13–15 June, 1984, at the Remeis-Sternwarte Bamberg, Germany, to commemorate the 200th anniversary of the birth of Friedrich Wilhelm Bessel (1784–1846). 相似文献
The idea that deka-keV electrons, accelerated during the primary energy release, are responsible for the bulk of the impulsive phase energy transport in solar flare atmospheres has been around for quite some time now. With the advent of (i) detailed numerical calculations of the hydrodynamic response of the atmosphere to the energy input from such electrons, and (ii) the observations made during the last solar maximum of the spatial, spectral, and temporal behavior of flare-associated emissions in a variety of wavelength ranges, we have now reached a point where quantitative tests of the thick-target electron-heated model (Brown, 1973) are possible. Here I describe some recent results of such quantitative tests.
I recount my career in solar physics beginning at Ondřejov Observatory in 1948 and ending with my ∼30 year stay at the Laboratory
of Space Research in Utrecht. 相似文献
This summary lecture makes no attempt to summarize what was actually said at the meeting, since this is well covered by the
other contributors. Instead I have structured my presentation in three parts: First I try to demonstrate why the Sun is unique
by comparing it with laboratory plasmas. This is followed by some personal reminiscences that go back a significant fraction
of the century. I conclude in the form of a poem about this memorable conference in honor of the centennial anniversary of
the Kodaikanal Observatory. 相似文献
