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Books > Science & Mathematics > Astronomy, space & time > Solar system > General
The Study of Travelling Interplanetary Phenomena (STIP) was formally established by the International Council of Scientific Unions' Special Committee on Solar-Terrestrial Physics (SCOSTEP) in August 1973 with M. Dryer as Convenor and M. A. Shea as Secretary. The scientific objec tives of STIP are the study and search for understanding of quiet (i.e. normal or background) and active periods in the interplanetary medium. The concepts of informal, extemporaneous interdisciplinary research is continuo sly emphasised, and these concepts have proved to be extremely successful in conducting the very productive studies undertaken by the members. About 200 scientists are actively participating in STIP, their interests ranging from solar physics (insofar as it concerns the initi ation of phenomena which move out from the Sun) to the observation and study of comets and planetary magneto spheres and ionospheres. Solar wind plasma and fields, solar and galactic cosmic rays, interstellar interactions, solar radio astronomy and interplanetary scintillations of discrete radio sources are among the topics of interest."
This book presents the latest knowledge of the newly discovered Earth-like exoplanets and reviews improvements in both radio and optical SETI. A key aim is to stimulate fresh discussion on algorithms that will be of high value in this extremely complicated search. Exoplanets resembling Earth could well be able to sustain life and support the evolution of technological civilizations, but to date, all searches for such life forms have proved fruitless. The failings of SETI observations are well recognized, and a new search approach is necessary. In this book, different detection algorithms that exploit state-of-the-art, low-cost, and extremely fast multiprocessors are examined and compared. Novel methods such as the agnostic entropy and high-sensitivity blind signal extraction algorithms should represent a quantum leap forward in SETI. The book is of interest to all researchers in the field and hopefully stimulates significant progress in the search for extraterrestrial intelligence.
"Meteoric phenomena" is the accepted term for the complex of physi cal phenomena that accompany the entry of meteoric bodies into the at mosphere of the earth (or of any planet). "Meteoric bodies" are usually defined as cosmic bodies observed by optical or radar techniques, when they enter the atmosphere. The limiting sensitivity of present-day radar equipment makes it possible to record meteors of up to stellar magnitude +14, while the most brilliant bolides may reach magnitude -19. On a mass 7 7 scale this corresponds approximately to a range of 10- to 10 g. How ever, met or astronomy is also concerned with larger objects, namely crater-forming meteorites, or objects that cause large-scale destruction when they arrive through the atmosphere (an example is the Tunguska River meteorite). Consideration of the interaction of such objects with 12 the terrestrial atmosphere extends the mass range to 10 g. On the other hand, scientists studying fragmentation processes in meteoric bod 7 ies have to consider particles with masses less than 10- g, and the use of data from meteoric-particle counters on rockets and artificial satel lites, from microcraters on the lunar surface, and from noctilucent clouds 12 lowers the minimum mass to 10- g. Therefore, the mass range of meteoric bodies, or meteoroids, encompasses 24 orders of magnitude. Although recent years have witnessed considerable development in meteor research, both in the Soviet Union and elsewhere, the main mono graphs on meteor physics were published twenty or more years ago."
Written by active research scientists who study the volcanism of Earth and of other planets, the contributions provide the first general review of volcanic activity throughout the Solar System. Successive chapters describe past and present volcanic activity as it is observed throughout the Solar System. These chapters relate to readers not only our present knowledge of volcanism throughout the Solar System but also how frontline scientists working in this field conduct their research.
1. 1. Short History of Solar Radio Astronomy Since its birth in the forties of our century, solar radio astronomy has grown into an extensive scientific branch comprising a number of quite different topics covering technical sciences, astrophysics, plasma physics, solar-terrestrial physics, and other disciplines. Historically, the story of radio astronomy goes back to the times of James Clerk Maxwell, whose well known phenomenological electromagnetic field equations have become the basis of present-time radio physics. As a direct consequence of these equations, Maxwell was able to prognosticate the existence of radio waves which fifteen years later were experimentally detected by the famous work of Heinrich Hertz (1887/88). However, all attempts to detect radio waves from cosmic objects failed until 1932, which was mainly due to the early stage of development of receiving techniques and the as yet missing knowledge of the existence of a screening ionosphere (which was detected in 1925). Therefore, famous inventors like Thomas Edison and A. E. Kennelly, as well as Sir Oliver Lodge, were unsuccessful in receiving any radio emission from the Sun or other extraterrestrial sources. Another hindering point was that nobody could a priori expect that solar radio emission should have something to do with solar activity so that unfortunately by chance some experiments were carried out just at periods of low solar activity. This was also why Karl Guthe Jansky at the birth of radio astronomy detected galactic radio waves but no emission from the Sun.
Space debris and asteroid impacts pose a very real, very near-term threat to Earth. In order to help study and mitigate these risks, the Stardust program was formed in 2013. This training and research network was devoted to developing and mastering techniques such as removal, deflection, exploitation, and tracking. This book is a collection of many of the topics addressed at the Final Stardust Conference, describing the latest in asteroid monitoring and how engineering efforts can help us reduce space debris. It is a selection of studies bringing together specialists from universities, research institutions, and industry, tasked with the mission of pushing the boundaries of space research with innovative ideas and visionary concepts. Topics covered by the Symposium: Orbital and Attitude Dynamics Modeling Long Term Orbit and Attitude Evolution Particle Cloud Modeling and Simulation Collision and Impact Modelling and Simulation, Re-entry Modeling and Simulation Asteroid Origins and Characterization Orbit and Attitude Determination Impact Prediction and Risk Analysis, Mission Analysis-Proximity Operations, Active Removal/Deflection Control Under Uncertainty, Active Removal/Deflection Technologies, and Asteroid Manipulation
This volume contains five articles describing the mission and its instruments. The first paper, by the project scientist Richard C. Elphic and his colleagues, describes the mission objectives, the launch vehicle, spacecraft and the mission itself. This is followed by a description of LADEE's Neutral Mass Spectrometer by Paul Mahaffy and company. This paper describes the investigation that directly targets the lunar exosphere, which can also be explored optically in the ultraviolet. In the following article Anthony Colaprete describes LADEE's Ultraviolet and Visible Spectrometer that operated from 230 nm to 810 nm scanning the atmosphere just above the surface. Not only is there atmosphere but there is also dust that putatively can be levitated above the surface, possibly by electric fields on the Moon's surface. Mihaly Horanyi leads this investigation, called the Lunar Dust Experiment, aimed at understanding the purported observations of levitated dust. This experiment was also very successful, but in this case their discovery was not the electrostatic levitation of dust, but that the dust was raised by meteoroid impacts. This is not what had been expected but clearly is the explanation that best fits the data. Originally published in Space Science Reviews, Volume 185, Issue 1-4, 2014.
New Horizons: Reconnaissance of the Pluto-Charon System and the Kuiper Belt C. T. Russell Originally published in the journal Space Science Reviews, Volume 140, Nos 1-4, 1-2. DOI: 10. 1007/s11214-008-9450-0 (c) Springer Science+Business Media B. V. 2008 Exploration is mankind's imperative. Since the beginnings of civilization, men and women have not been content to build a wall around their settlements and stay within its con nes. They explored the land around them, climbed the mountains, and scanned the horizons. The boldest among them pushed exploration to the most distant frontiers of the planet. As a result, much of the Earth was inhabited well before the days of the renowned European - th th plorers of the 15 and 16 centuries. Exploration did not cease, after the circumnavigation of the globe; it continued to the present. Today explorers are going in new directions, not just east and west, north and south. They explore backward in time and upward in space. Arc- ology explores the shorter time scales, and geochemistry the longer time scales of geophy- cal events: asteroidal and cometary collisions, magnetic reversals, continental formation and more. However, on Earth we cannot go back inde nitely, for much of the evidence of the very earliest days has been lost.
This book is an original study aimed at understanding how vacuum magnetic fields change with time. Specifically, it describes the waves that radiate from a sphere when the electric current on its surface is turned on or off, either suddenly, gradually, or periodically. Numerical simulations are an invaluable source of information about this and related subjects, but they are often more difficult to interpret than exact, closed-form solutions that can easily be applied to a variety of situations. Thus, the objective here is to obtain an exact solution of Maxwell's equations in closed form-something simple, yet rigorous, which can be used as a model for understanding transient magnetic fields in more complicated situations. The work therefore stands as a self-contained solution of Maxwell's equations for an electric current wrapped around the surface of a sphere. This study assumes a strong background in electromagnetism or a related research area. Online animations are available for each figure to better illustrate the motions of magnetic field lines.
This book is a historical-epistemological study of one of the most consequential breakthroughs in the history of celestial mechanics: Robert Hooke's (1635-1703) proposal to "compoun[d] the celestial motions of the planets of a direct motion by the tangent & an attractive motion towards a centrat body" (Newton, The Correspondence li, 297. Henceforth: Correspondence). This is the challenge Hooke presented to Isaac Newton (1642-1727) in a short but intense correspondence in the winter of 1679-80, which set Newton on course for his 1687 Principia, transforming the very concept of "the planetary heavens" in the process (Herivel, 301: De Motu, Version III). 1 It is difficult to overstate the novelty of Hooke 's Programme * The celestial motions, it suggested, those proverbial symbols of stability and immutability, werein fact a process of continuous change: a deflection of the planets from original rectilinear paths by "a centraU attractive power" (Correspondence, li, 313). There was nothing necessary or essential in the shape of planetary orbits. Already known to be "not circular nor concentricall" (ibid. ), Hooke claimed that these apparently closed "curve Line[ s ]" should be understood and calculated as mere effects of rectilinear motions and rectilinear attraction. And as Newton was quick to realize, this also implied that "the planets neither move exactly in ellipse nor revolve twice in the same orbit, so that there are as many orbits to a planet as it has revolutions" (Herivel, 301: De Motu, Version III).
9 MHDTurbulence in the Heliosphere: Evolution and Intermittency 253 Bruno Bavassano, Roberto Bruno and Vincenzo Carbone 1 Introduction 254 2 MHD Turbulence Evolution 255 2. 1 Ecliptic Turbulence 256 2. 2 Polar Turbulence 258 2. 3 Conclusions on Turbulence Evolution 263 3 Intermittency 264 3. 1 Probability Distribution Functions of Fluctuations and Self-similarity 269 3. 2 Radial Evolution of Intermittency 271 3. 3 Identifying Intermittent Events 273 3. 4 Conclusions on Intermittency 277 10 283 Waves and Turbulence in the Solar Corona Eckart Marsch 1 Introduction 284 2 Coronal Magnetic Field Structures 284 3 Magnetic Network Activity and Coronal Heating 287 4 Waves and Flows in Loops and Funnels 290 5 Magnetohydrodynamic Waves and Flux Tube Oscillations 293 5. 1 Observation and Theory 293 5. 2 Oscillations of Thin Flux Tubes 295 5. 3 Wave Amplitudes Versus Height from Numerical Mod- ~ 2~ 5. 4 A Standing Slow Magnetoacoustic Wave 299 6 Plasma Waves and Heating of Particles 301 7 Generation, Transfer and Dissipation of Coronal Turbulence 303 7. 1 Generation of Magnetohydrodynamic Waves 303 7. 2 Wave Energy Transfer and Turbulent Cascade 304 7. 3 Wave Dissipation in the Kinetic Domain 307 7. 4 Origin and Generation of Coronal High-Frequency Waves 308 7.
The IAU Symposium No. 62, 'The Stability of the Solar System and of Small Stellar Systems' was held in Warsaw in Poland during the Extraordinary General Assembly of the IAU in commemoration of the SOOth anniversary of the birth of Nicolaus Copernicus. The Symposium was sponsored by Commission 7 (Celestial Mechanics) and cosponsored by Commissions 4 (Ephemerides) and 37 (Star Clusters and Asso- ciations) of the IAU and by IUTAM. The Organizing Committee included Y. Kozai (Chairman), J. A. Agekjan, A. Deprit, G. N. Duboshin, S. G\lska (Local represen- tative), M. Henon, B. Morando and C. Parkes (IUTAM representative). The Symposium was supported financially by the IA U, the IUT AM and the Polish Academy of Sciences. Y. KOZAI Chairman of the Organizing Committee STABILITY THEORY IN CELESTIAL MECHANICS J MOSER Courant Institute of Mathematical ScIences, New York University, New York, N. Y. 10012, U.S.A. Abstract, This expository lecture surveys recent progress of the stability theory in Celestial Mechanics with emphasis on the analytical problems. In particular, the old question of convergence of perturbation series are discussed and positive results obtained, in the light of the work by Kolmogorov Arnold and Moser. For the three body problem, classes of quasi-periodic solutions and doubly asymptotic (or homo- clinic) orbits are discussed.
A new and detailed picture of Mercury is emerging thanks to NASA's MESSENGER mission that spent four years in orbit about the Sun's innermost planet. Comprehensively illustrated by close-up images and other data, the author describes Mercury's landscapes from a geological perspective: from sublimation hollows, to volcanic vents, to lava plains, to giant thrust faults. He considers what its giant core, internal structure and weird composition have to tell us about the formation and evolution of a planet so close to the Sun. This is of special significance in view of the discovery of so many exoplanets in similarly close orbits about their stars. Mercury generates its own magnetic field, like the Earth (but unlike Venus, Mars and the Moon), and the interplay between Mercury's and the Sun's magnetic field affects many processes on its surface and in the rich and diverse exosphere of neutral and charged particles surrounding the planet. There is much about Mercury that we still don't understand. Accessible to the amateur, but also a handy state-of-the-art digest for students and researchers, the book shows how our knowledge of Mercury developed over the past century of ground-based, fly-by and orbital observations, and looks ahead at the mysteries remaining for future missions to explore.
The general background of this monograph and the aim of it is described in detail in Chapter I. As stated in 1.7 it is written according to the principle that "when rigour appears to conflict with simplicity, simplicity is given preference," which means that it is intended for a rather broad public. Not only graduate students but also advanced undergraduates should be able to understand at least most of it. This monograph is the result of many years of inspiring discussions with a number of colleagues, for which I want to thank them very much. Especially I should mention the groups in Stockholm and La Jolla: in Stockholm, Dr Carl-Gunne Flilthammar and many of his collaborators, including Drs Lars Block, Per Carlqvist, Lennart lindberg, Michael Raadu, Staffan Torven, Miroslav Babic, and Itlgvar Axniis, and further, Drs Bo Lehnert and Bjorn Bonnevier, all at the Royal Institute of Technology. Of other col leagues in Sweden, I should mention Dr Bertel Laurent, Stockholm University, Dr Aina Elvius, The Stockholm Observatory, and Dr Bengt Hultqvist, Kiruna. In La Jolla my thanks go first of all to Dr Gustaf Arrhenius, who once invited me to La Jolla, which was the start of a most interesting collaboration; further, to Dr W. B."
ix Fully aware of the work accomplished by Mgr. Lemattre, His Majesty King Baudouin enhanced this occasion by placing it under His High Patronage. His Holiness the Pope Jean-Paul II accepted to testify his paternel solicitude for the work of the scientists participating in the symposium. The President of the pontifical Academy of Sciences and the Director of the Vatican Observatory transmitted their fervent wishes for the full success of the symposium. Numerous other eminent people graced the ceremony with their patronage. The academic opening, the addresses of which are pub*lished by the Revue des Questions Scientifiques de Bruxelles , was presided over by Mgr. E. Massaux, Rector of the Catholic University of Louvain who spoke about Lemattre, the University professor. Professor Ch. de Duve, Nobel Prize winner in Medicine, called to mind the role of Lemattre as President of the Pontifical Academy of Sciences; the Emeritus Professor O. Godart, founder of the Institute, recalled the life and work of Mgr. Lemattre; Professor A. Deprit, Senior Mathematician at the National Bureau of Standards, spoke about Lemattre' s work in celestial mechanics and his keen interest for computers; Professor J. Peebles, Professor of Physics at Princeton University, summarized the fundamental contributions of Lemattre to modern cosmology. The attendance of more than three hundred people was enhanced by the presence of Mgr. A. Pedroni, Papal Nuncio, Mr Ph. Maystadt, Minister of Research Policy, Mr E. Knoops, Secretary of State, Mr Y. de Wasseige, Senator, Professor E.
Most of the visible matter in the universe exists in the plasma state. Plasmas are of major importance for space physics, solar physics, and astrophysics. On Earth they are essential for magnetic controlled thermonuclear fusion. This textbook collects lecture notes from a one-semester course taught at the K.U. Leuven to advanced undergraduate students in applied mathematics and physics. A particular strength of this book is that it provides a low threshold introduction to plasmas with an emphasis on first principles and fundamental concepts and properties. The discussion of plasma models is to a large extent limited to Magnetohydrodynamics (MHD) with its merits and limitations clearly explained. MHD provides the students on their first encounter with plasmas, with a powerful plasma model that they can link to familiar classic fluid dynamics. The solar wind is studied as an example of hydrodynamics and MHD at work in solar physics and astrophysics.
This volume presents the latest research results on solar prominences, including new developments on e.g. chirality, fine structure, magnetism, diagnostic tools and relevant solar plasma physics. In 1875 solar prominences, as seen out of the solar limb, were described by P.A. Secchi in his book Le Soleil as "gigantic pink or peach-flower coloured flames". The development of spectroscopy, coronagraphy and polarimetry brought tremendous observational advances in the twentieth century. The authors present and discuss exciting new challenges (resulting from observations made by space and ground-based telescopes in the 1990s and the first decade of the 21st century) concerning the diagnostics of prominences, their formation, their life time and their eruption along with their impact in the heliosphere (including the Earth). The book starts with a general introduction of the prominence "object" with some historical background on observations and instrumentation. In the next chapter, the various forms of prominences are described with a thorough attempt of classification. Their thermodynamic (and velocity) properties are then derived with emphasis on the methods (and their limits) used. This goes from the simplest optically thin case to the heavy radiative treatment of plasmas out of local thermodynamic equilibrium. The following chapters are devoted to the magnetic field measurements and indirect derivation. A new branch of diagnostic tools, the seismology, is presented along with some MHD basics. This allows to better understand the propagation of waves, the energy and force equilibria. Both small-scale and large-scale studies and their relationship are presented. The importance of the newly discovered cavities is stressed in the context of prominence destabilization. The issues of prominence formation and eruption, their connection with flares and Coronal Mass Ejections and their impact on the Earth are addressed on the basis of the latest results. Finally, an exciting new area of research is unveiled with the newly discovered evidence of similar manifestations in the Universe and their possible impact on the habitability of exoplanets. References to the basic physics (where necessary) are provided and the proposed web sites addresses will allow the reader to load exciting movies. The book is aimed at advanced students in astrophysics, post-graduates, solar physicists and more generally astrophysicists. Amateurs will enjoy the many new images which go with the text.
Space storms, the manifestation of bad weather in space, have a
number of physical effects in the near-Earth environment:
acceleration of charged particles in space, intensification of
electric currents in space and on the ground, impressive aurora
displays, and global magnetic disturbances on the Earth's surface.
Space weather has been defined as conditions on the Sun and in the
solar wind, magnetosphere, ionosphere, and atmosphere that can
influence the performance and reliability of space- and
ground-based technological systems and can endanger human life'.
The 19 chapters of this book, written by some of the foremost
experts on the topic, present the most recent developments in space
storm physics and related technological issues, such as malfunction
of satellites, communication and navigation systems, and electric
power distribution grids. As recommended in the United Nations Space & Atmospheric Science Education Curriculum booklet. Please find it amongst classics such as T.J.M. Boyd, J.J. Sanderson, J.K. Hargreaves and M.C. Kelly etc.
This book contains the lectures presented at the International Workshop on Relation between Laboratory and Space Plasmas held at Gakushi-Kaikan (University Alumni Association) Kanda in Tokyo, Japan on 14 - 15 April, 1980. Its aim was to bring together laboratory, fusion and space plasma physicists and to highlight the communality of basic plasma phenomena, similarities and differences observed in the laboratory and in space, thus exchanging information tnd views on new ideas to link both areas. Although similar type of conferences were held in Europe and recently in the States, this is the first time we have had in Japan for such an international meeting, which may be regarded as an extended version of our national Workshop held twice at the Institute of Plasma Physics of Japan (IPPJ) in 1976 and in 1977 (IPPJ Research Report No. 286 and No. 365). The Workshop consisted of seven regular sessions and one special session with approximately ninety participants from allover the world. Thirty-six papers, invited and contributed, were presented, nine from U. S. A., three from U. S. S. R., two of each from Germany, France, India, one of each from Sweden, Canada, Belgium and fifteen from Japan. The topics covered were: (1) The Critical Velocity (2) Beam Plasma Discharges and Interactions (3) Double Layers and Shocks (4) Instabilities in the Equatorial and Auroral Electrojets (5) Turbulent and Anomalous Plasmas (6) Plasma Irregularities (7) Solar Plasma Phenomena (8) Active Experiments in Space Plasmas and Their Simulation in the Laboratory.
This volume has grown out of lectures addressing primarily graduate students and researchers working in related areas in both astrophysics and space sciences. All contributions are self-contained and do not require prior in-depth knowledge of solar physics. The result is a unique textbook that fulfills the needs of those wishing to have a pedagogic exposition of solar physics bringing them up-to-date in a field full of vitality and with exciting research.
Although the development of ideas about the motion and trajectory of comets has been investigated piecemeal, we lack a comprehensive and detailed survey of ph- ical theories of comets. The available works either illustrate relatively short periods in the history of physical cometology or portray a landscape view without adequate details. The present study is an attempt to review - with more details - the major physical theories of comets in the past two millennia, from Aristotle to Whipple. My research, however, did not begin with antiquity. The basic question from which this project originated was a simple inquiry about the cosmic identity of comets at the dawn of the astronomical revolution: how did natural philosophers and astronomers define the nature and place of a new category of celestial objects - comets - after Brahe's estimation of cometary distances? It was from this turning point in the history of cometary theories that I expanded my studies in both the pre-modern and modern eras. A study starting merely from Brahe and ending with Newton, without covering classical and medieval thought about comets, would be incomplete and leave the fascinating achievements of post-Newtonian cometology unexplored.
Taking both a theoretical and observational perspective, this book is an introduction to recent developments in the field of celestial mechanics. It emphasizes the application to extended celestial bodies and devotes much attention to rotational aspects. In particular, it explains the state of art for accurate modelling of the rotation of celestial bodies such as the Earth, the Moon, and Mercury, which involves principles related to hydrodynamics and geodesy. Comparisons between the light curves of the asteroids and their rotational state are made and spatial techniques leading to the determination of the Earth's gravitational field are explained. Also, the book provides a general overview of the collisional processes in the solar system and of the dynamics of the rings. It is addressed to graduate students and researchers in space sciences and celestial dynamics.
"Infrared Solar Physics" contains the proceedings of the 154th Symposium of the International Astronomical Union. Aimed at active workers and graduate students in solar physics, this volume provides a comprehensive view of a rapidly expanding discipline that gives us a new perspective on the sun. Measurements across the wide infrared spectral range can probe the solar atmosphere from below the visible surface through the outer reaches of the corona. Taking full advantage of revolutionary advances in detector technology, infrared observations from the ground, aircraft and space have led to a better understanding of solar magnetic fields, atmospheric structure and activity, and elemental abundances. The infrared has also provided new interpretive challenges, such as the appearance of the 12mm emission lines of magnesium. These and other developments are discussed by leading contributors, who also give their perspectives on the future of this field of study.
NASA's Advanced Composition Explorer (ACE) was launched on August 25, 1997, carrying six high-resolution spectrometers that measure the abundances of the elements, isotopes, and ionic charge states of energetic nuclei in space. Data from these instruments is being used to measure and compare the composition of the solar corona, the nearby interstellar medium, and cosmic-ray sources in the Galaxy, and to study particle acceleration processes in a variety of environments. ACE also includes three instruments that monitor solar wind and energetic particle activity near the inner Lagrangian point, "1.5 million kilometers sunward of Earth, and provide continuous, real-time data to NOAA for use in forecasting space weather. Eleven of the articles in this volume review scientific progress and outline questions that ACE will address in solar, space-plasma, and cosmic-ray physics. Other articles describe the ACE spacecraft, the real-time solar-wind system, and the instruments used to measure energetic particle composition. |
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