The years 2012/2013 mark the 50th anniversary of the theoretical prediction that Brown Dwarfs, i.e. degenerate objects which are just not massive enough to sustain stable hydrogen fusion, exist. Some 20 years after their discovery, how Brown Dwarfs form is still one of the main open questions in the theory of star formation. In this volume, the pioneers of Brown Dwarf research review the history of the theoretical prediction and the subsequent discovery of Brown Dwarfs. After an introduction, written by Viki Joergens, reviewing Shiv Kumar's theoretical prediction of the existence of brown dwarfs, Takenori Nakano reviews his and Hayashi's calculation of the Hydrogen Burning Minimum Mass. Both predictions happened in the early 1960s. Jill Tarter then writes on the introduction of the term 'Brown Dwarf', before Ben Oppenheimer, Rafael Rebolo and Gibor Basri describe their first discovery of Brown Dwarfs in the 1990s. Lastly, Michael Cushing and Isabelle Baraffe describe the development of the field to the current state of the art. While the book is mainly aimed at the Brown Dwarf research community, the description of the pioneering period in a scientific field will attract general readers interested in astronomy as well.

Theideatocelebrate50yearsoftheSalpeterIMFoccurredduringtherecent IAU General Assembly in Sydney, Australia. Indeed, it was from Australia that in July 1954 Ed Salpeter submitted his famous paper "The Luminosity Function and Stellar Evolution" with the rst derivation of the empirical stellar IMF. This contribution was to become one of the most famous astrophysics papers of the last 50 years. Here, Ed Salpeter introduced the terms "original mass function" and "original luminosity function", and estimated the pro- bility for the creation of stars of given mass at a particular time, now known as the "Salpeter Initial Mass Function", or IMF. The paper was written at the Australian National University in Canberra on leave of absence from Cornell University (USA) and was published in 1955 as 7 page note in the Astroph- ical Journal Vol. 121, page 161. To celabrate the 50th anniversary of the IMF, along with Ed Salpeter’s 80th birthday, we have organized a special meeting that brought together scientists involved in the empirical determination of this fundamental quantity in a va- ety of astrophysical contexts and other scientists fascinated by the deep imp- cations of the IMF on star formation theories, on the physical conditions of the gas before and after star formation, and on galactic evolution and cosmology. The meeting took place in one of the most beautiful spots of the Tuscan countryside, far from the noise and haste of everyday life.

This volume provides a state-of-the-art review of our current knowledge of brown dwarfs and very low-mass stars. The hunt for and study of these elusive objects is currently one of the most dynamic areas of research in astronomy for two reasons. Brown dwarfs bridge the gap between stars and planets, and they may constitute an important part of the 'dark matter' of the Universe. This volume presents review articles from a team of international authorities who gathered at a conference in La Palma to assess the spectacular progress that has been made in this field in the last few years.

Finally, the entire body of our scientific knowledge of the universe is available in one definitive volume. Scientific American, the oldest and most popular science magazine in the world, has prepared the most comprehensive and comprehensible book on the subject ever. Under the direction of renowned astronomer David H. Levy, this spectacular book assembles the best minds in science to give clear and accessible explanations of the nature of the cosmos. Newly commissioned essays by working scientists at the top of their fields and classic writings by such luminaries as Albert Einstein, Francis Crick, and Carl Sagan take us to the frontiers of space and time-from sub-atomic particles to the edge of the universe. Both thoughtful and provocative, this book asks-and answers-the big questions, such as: o How did our solar system evolve? o What forces lie at the center of the atom? o What is the size of the universe? o What is dark matter? o What is the possibility of extraterrestrial life? o What is the importance of superstrings? o How do galaxies form? Dazzling full-color and black-and-white photographs aid in articulating the latest theories about the size, age, nature, and expansion of the universe, and make this book a delight to behold. Essays are grouped by topic, from the largest phenomena, such as the formation of the universe, down to the smallest detail, such as the makeup of an atom. In addition, each section contains an illuminating introduction by David Levy that binds the essays together and creates a whole picture. The Scientific American Book of the Cosmos is a valuable addition to the bookshelf of both professional astronomers and science enthusiasts alike.

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Immerse yourself on an interstellar journey through "A Story of More than 5000 Worlds'' as it explores the fascinating story of celestial discovery and the enduring quest of researchers and scientists to find life beyond Earth. This comprehensive book navigates the intricacies of star and planet formation, shedding light on the enigmatic life cycle of stars like our Sun to pulsars and black holes and the dynamic processes that define the fate of planets. Marvel at the ingenuity of exoplanet detection methods, from the accurate detection of stellar wobbles to the precise monitoring of starlight dimming during transits, and peer into the future with innovative techniques that take advantage of the deformation or curvature of the space-time caused by massive objects. The classification of these distant worlds from rocky planets to gas giants lays the groundwork for the book's climax: the search for life. Exploring biosignatures and technosignatures, from the organic and chemical traces of potential life, to the echoes of advanced technological civilizations, this book expands our understanding of the dynamicity of the universe and our place within it. It's an invitation to ponder humanity's greatest question – are we alone? – while navigating through the Drake Equation and other Search for Extraterrestrial Intelligence (SETI) concepts, and the silence that has prompted ideas like the Fermi Paradox, and the Great Filter. The book, in addition to acting as an engaging read for anyone interested in these subjects and given the number of topics included and the breadth of the discussions, could also be used as a complementary textbook for students at both high school and non-science bachelor levels, in introductory or fundamental astronomy courses.

A fascinating account of the pioneering astronomer who claimed (erroneously) to have discovered a planet outside the solar system. There are innumerable planets revolving around innumerable stars across our galaxy. Between 2009 and 2018, NASA's Kepler space telescope discovered thousands of them. But exoplanets—planets outside the solar system—appeared in science fiction before they appeared in telescopes. Astronomers in the early decades of the twentieth century spent entire careers searching for planets in other stellar systems. In The Lost Planets, John Wenz offers an account of the pioneering astronomer Peter van de Kamp, who was one of the first to claim discovery of exoplanets. Van de Kamp, working at Swarthmore College's observatory, announced in 1963 that he had identified a planet around Barnard's Star, the second-closest star system to the Sun. He cited the deviations in Barnard's star's path—“wobbles” that suggested a large object was lurching around the star. Van de Kamp became something of a celebrity (appearing on a television show with “Mr. Wizard,” Don Henry), but subsequent research did not support his claims. Wenz describes van de Kamp's stubborn refusal to accept that he was wrong, discusses the evidence found by other researchers, and explains recent advances in exoplanet detection, including transit, radial velocity, direct imaging, and microlensing. Van de Kamp retired from Swarthmore in 1972, and died in 1995 at 93. In 2009, Swarthmore named its new observatory the Peter van de Kamp Observatory. In the 1990s, astronomers discovered and confirmed the first planet outside our solar system. In 2018, an exoplanet was detected around Barnard's Star—not, however, the one van de Kamp thought he had discovered in 1963.