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My interest in the history of the Struve family is long-standing but lay dormant until 1972, when I found myself organizing a symposium of the International Astronomical Union in memory of the second Otto Struve. To satisfy my own curiosity, I investigated the precise relationships of the famous astronomers in the family and published an account of them, based mainly on secondary sources. The exercise made me a ware that there was no biography in English of the first and probably still the greatest astronomer in the clan - Friedrich Georg Wilhelm Struve. Wilhelm's son, the first Otto, wrote an account (in German) of his father's life, intended primarily for family and close friends and --though printed-- not generally available. Through the kindness of a family member I have a copy from which I have been able to work. The Soviet historian of science, Z. K. Sokolovskaya, wrote a biography in Russian, in 1964, to mark the centenary of Wilhelm's death. This had a limited edition, and my efforts to obtain a copy failed. Neither work has, in its entirety, been translated into English, although Michael Meo of Oakland, California, and Kevin Krisciunas of Hilo, Hawaii, have kindly made available to me their unpublished translations of some sections of the latter. In the of a complete copy, however, when I decided to attempt an English absence language biography, I thought it best to do so independently of Sokolovskaya's.

The Journal on Advanced Studies in Theoretical and Experimental Physics, including Related Themes from Mathematics

Praise for the first edition: "A terrific blend of the science and the history." Martha Haynes, Goldwin Smith Professor of Astronomy, Cornell University, New York, USA "The book is a treat... Highly recommended for public and academic libraries." Peter Hepburn, now Head Librarian, College of the Canyons, Santa Clarita, California, USA Today, we recognize that we live on a planet circling the sun, that our sun is just one of billions of stars in the galaxy we call the Milky Way, and that our galaxy is but one of billions born out of the Big Bang. Yet, as recently as the early twentieth century, the general public and even astronomers had vague and confused notions about what lay beyond the visible stars. Can we see to the edge of the universe? Do we live in a system that would look, from a distance, like a spiral nebula? This fully updated second edition of Minding the Heavens: The Story of Our Discovery of the Milky Way explores how we learned that we live in a galaxy, in a universe composed of galaxies and unseen, mysterious dark matter. The story unfolds through short biographies of seven astronomers: Thomas Wright, William Herschel, and Wilhelm Struve of the eighteenth and nineteenth centuries; the transitional figure of William Huggins; and Jacobus Kapteyn, Harlow Shapley, and Edwin Hubble of the modern, big-telescope era. Each contributed key insights to our present understanding of where we live in the cosmos, and each was directly inspired by the work of his predecessors to decipher "the construction of the heavens." Along the way, the narrative weaves in the contributions of those in supportive roles, including Caroline Herschel—William’s sister, and the first woman paid to do astronomy—and Martha Shapley, a mathematician in her own right who carried out calculations for her spouse. Through this historical perspective, readers will gain a new appreciation of our magnificent Milky Way galaxy and of the beauties of the night sky, from ghostly nebulae to sparkling star clusters. Features: Fully updated throughout to reflect the latest in our understanding of the Milky Way, from our central supermassive black hole to the prospect of future mergers with other galaxies in our Local Group. Explains the significance of current research, including from the Gaia mission mapping our galaxy in unprecedented detail. Unique and broadly appealing approach. A biographical framework and ample illustrations lead the reader by easy, enjoyable steps to a well-rounded understanding of the history of astronomy. Leila Belkora (Ph.D., Astrophysics) is a science writer. She earned her doctorate from the University of Colorado-Boulder, specializing in solar radio astronomy. She has previously taught university physics, astronomy, and communication for engineers. She lives in Southern California and enjoys local astronomy outreach activities.

Current Aspects of Exobiology covers the philosophical aspects, scientific approach, and related research problems in exobiology. Most of the chapters are presented at the Current Research in Exobiology Symposium, held at the Jet Propulsion Laboratory on February 26-28, 1963. This book is composed of 10 chapters and begins with an overview of the nature and occurrence of extraterrestrial living matter. The next chapters survey certain line of evidence concerning extraterrestrial life, including investigation of organo-chemical evolution, organic remains in meteorites, microorganisms of Middle Precambrian Age, and the survival capabilities and the performance of earth organisms in simulated extraterrestrial environments. These topics are followed by discussions on the interesting issues on the possibility of a primordial lunar life and the possibilities of life on mars. A chapter considers the various scientific efforts to detect life outside earth, including experiments on small, unmanned biological laboratories to the surfaces of the planets. Another chapter looks into the possibility of the accidental introduction of terrestrial microorganisms to other planets during the course of space exploration by unmanned spacecraft. The concluding chapters explore the potential of radio search for other intelligent species in space. Exobiologists and researchers in the related fields of exobiology who are interested in extraterrestrial life will find this book invaluable.

Design optics and technology for large spaceborne astronomical telescopes.

The last 50 years have seen a tremendous progress in the research on quasars. From a time when quasars were unforeseen oddities, we have come to a view that considers quasars as active galactic nuclei, with nuclear activity a coming-of-age experienced by most or all galaxies in their evolution. We have passed from a few tens of known quasars of the early 1970s to the 500,000 listed in the catalogue of the Data Release 14 of the Sloan Digital Sky Survey. Not surprisingly, accretion processes on the central black holes in the nuclei of galaxies — the key concept in our understanding of quasars and active nuclei in general — have gained an outstanding status in present-day astrophysics. Accretion produces a rich spectrum of phenomena in all bands of the electromagnetic spectrum. The power output of highly-accreting quasars has impressive effects on their host galaxies. All the improvement in telescope light gathering and in computing power notwithstanding, we still miss a clear connection between observational properties and theory for quasars, as provided, for example, by the H-R diagram for stars. We do not yet have a complete self-consistent view of nuclear activity with predictive power, as we do for main-sequence stellar sources. At the same time quasars offer many “windows open onto the unknown". On small scales, quasar properties depend on phenomena very close to the black hole event horizon. On large scales, quasars may effect evolution of host galaxies and their circum-galactic environments. Quasars’ potential to map the matter density of the Universe and help reconstruct the Universe’s spacetime geometry is still largely unexploited. The times are ripe for a critical assessment of our present knowledge of quasars as accreting black holes and of their evolution across the cosmic time. The foremost aim of this research topic is to review and contextualize the main observational scenarios following an empirical approach, to present and discuss the accretion scenario, and then to analyze how a closer connection between theory and observation can be achieved, identifying those aspects of our understanding that are still on a shaky terrain and are therefore uncertain knowledge. This research topic covers topics ranging from the nearest environment of the black hole, to the environment of the host galaxies of active nuclei, and to the quasars as markers of the large scale structure and of the geometry of spacetime of the Universe. The spatial domains encompass the accretion disk, the emission and absorption regions, circum-nuclear starbursts, the host galaxy and its interaction with other galaxies. Systematic attention is devoted to some key problems that remain outstanding and are clearly not yet solved: the existence of two quasar classes, radio quiet and radio loud, and in general, the systematic contextualization of quasar properties the properties of the central black hole, the dynamics of the accretion flow in the inner parsecs and the origin of the accretion matter, the quasars’ small and large scale environment, the feedback processes produced by the black hole into the host galaxy, quasar evolutionary patterns from seed black holes to the present-day Universe, and the use of quasars as cosmological standard candles. The timing is appropriate as we are now witnessing a growing body of results from major surveys in the optical, UV X, near and far IR, and radio spectral domains. Radio instrumentation has been upgraded to linear detector — a change that resembles the introduction of CCDs for optical astronomy — making it possible to study radio-quiet quasars at radio frequencies. Herschel and ALMA are especially suited to study the circum-nuclear star formation processes. The new generation of 3D magnetohydrodynamical models offers the prospective of a full physical modeling of the whole quasar emitting regions. At the same time, on the forefront of optical astronomy, applications of adaptive optics to long-slit spectroscopy is yielding unprecedented results on high redshift quasars. Other measurement techniques like 2D and photometric reverberation mapping are also yielding an unprecedented amount of data thanks to dedicated experiments and instruments. Thanks to the instrumental advances, ever growing computing power as well as the coming of age of statistical and analysis techniques, the smallest spatial scales are being probed at unprecedented resolution for wide samples of quasars. On large scales, feedback processes are going out of the realm of single-object studies and are entering into the domain of issues involving efficiency and prevalence over a broad range of cosmic epochs. The Research Topic "Quasars at all Cosmic Epochs" collects a large fraction of the contributions presented at a meeting held in Padova, sponsored jointly by the National Institute for Astrophysics, the Padova Astronomical Observatory, the Department of Physics and Astronomy of the University of Padova, and the Instito de Astrofísica de Andalucía (IAA) of the Consejo Superiór de Investigación Cientifica (CSIC). The meeting has been part of the events meant to celebrate the 250th anniversary of the foundation of the Padova Observatory.