Radiating fire and ice, comets as a phenomenon seem part science, part myth. Two thousand years ago when a comet shot across the night sky, it convinced the Romans that Julius Caesar was a god. In 1066, Halley’s Comet was interpreted as a foreshadowing of the death of Harold the Second in the Battle of Hastings. Even today the arrival of a comet often feels auspicious, confirming our hopes, fears, and sense of wonder in the universe. In Comets, P. Andrew Karam takes the reader on a far-ranging exploration of these most beautiful and dramatic objects in the skies, revealing how comets and humanity have been interwoven throughout history. He delves into the science of comets and how it has changed over time; the way comets have been depicted in art, religion, literature, and popular culture; and how comets have appeared in the heavens through the centuries. Comprehensive in scope and beautifully illustrated throughout, the book will appeal not only to the budding astronomer, but to anyone with an appreciation for these compelling and remarkable celestial bodies.

Plain-language explanations and a rich set of supporting material help students understand the mathematical concepts and techniques of astronomy.

Collects six short illustrated volumes covering topics in mathematics, physics, chemistry, biology, evolution, and astronomy.

Reprint of the original, first published in 1869.

The writings of more than 60 authors including Isaac Asimov, Albert Einstein, Stephen Hawking, Pierre Curie, Primo Levi and James Gleick, are represented in this volume. Each expresses a perspective on the Sciences.

This book contains new translations and a new analysis of the procedure texts of Babylonian mathematical astronomy, the earliest known form of mathematical astronomy of the ancient world. The translations are based on a modern approach incorporating recent insights from Assyriology and translation science. The work contains updated and expanded interpretations of the astronomical algorithms and investigations of previously ignored linguistic, mathematical and other aspects of the procedure texts. Special attention is paid to issues of mathematical representation and over 100 photos of cuneiform tablets dating from 350-50 BCE are presented. In 2-3 years, the author intends to continue his study of Babylonian mathematical astronomy with a new publication which will contain new editions and reconstructions of approx. 250 tabular texts and a new philological, astronomical and mathematical analysis of these texts. Tabular texts are end products of Babylonian math astronomy, computed with algorithms that are formulated in the present volume, Procedure Texts.

Dark Matter, Dark Energy and Dark Gravity make life possible!This book for the lay reader provides a summary of the latest astrophysical observational results and theoretical insights into what we know and what we hope to learn about dark matter, dark energy, and dark gravity.How did the profound beauty of our Earth, our Solar System, our Milky Way galaxy and indeed our universe unfold? Dark matter, dark energy, and dark gravity have made all the difference in how the universe has developed, and have been key to creating the overall environment that makes life possible. We have only recently developed the ability to begin unlocking their secrets, thus providing a deeper insight into how a universe of our type is possible. It seems that because of dark matter, dark energy and dark (weak) gravity, our universe has the right attributes for the development of complex structure and the evolution of intelligent life that can engage in the quest to understand our world. These "dark" or more hidden attributes of the cosmos have very good outcomes.In particular, the existence of dark matter makes it easier to form complex structures, including galaxies, stars and planets through gravitational collapse of denser regions of the universe. Planets are the most suitable abodes for the development of life. Dark energy acts to extend the lifetime of the universe by counteracting gravity and driving continued expansion of the universe.Even as far back as the 1930s there has been evidence that most of the matter in the universe was not visible via electromagnetic radiation (optical light, radio waves, etc.). By the last few decades of the 20th century, the case for a considerable amount of this dark matter was very strong. It is the second largest contributor to the total mass-energy of the universe. We don't know what it is and there are various candidates to explain it; nevertheless we see the gravitational effects of dark matter everywhere on the largest scales. Recent observational results indicate that dark matter dominates by a factor of 6 relative to the ordinary matter that makes up stars, planets, and living things.We now know that the major contributor to the mass-energy of the universe is not the substantial dark matter, but the 'newer' so-called dark energy. Dark energy acts to some extent as a negative gravity, and for the last several billion years has driven the expansion of the universe to a faster and faster pace, overcoming even the gravitational effect of dark matter. We have a general idea that it is the irreducible energy found in every volume of space, even in the absence of matter - in the vacuum. We don't understand why it takes the value that it does, one that is small in quantum particle physics terms, but nevertheless is of great significance on the large cosmological scale of the universe. The third important aspect to consider is not a mass-energy component, but the nature of gravity and space-time. The big question here is - why is gravity so relatively weak, as compared to the other 3 forces of nature? These 3 forces are the electromagnetic force, the strong nuclear force, and the weak nuclear force. Gravity is different - it has a dark or hidden side. It may very well operate in extra dimensions beyond the normal 4 dimensions of space-time that we can observe. This is what we mean in this book by "dark gravity".

Astrophysics is often - with some justification - regarded as incomprehensible without at least degree-level mathematics. Consequently, many amateur astronomers skip the math, and miss out on the fascinating fundamentals of the subject. In Astrophysics Is Easy! Mike Inglis takes a quantitative approach to astrophysics that cuts through the incomprehensible mathematics, and explains the basics of astrophysics in accessible terms. The reader can view objects under discussion with commercial amateur equipment.

Plato’s view that mathematics paves the way for his philosophy of forms is well known. This book attempts to flesh out the relationship between mathematics and philosophy as Plato conceived them by proposing that in his view, although it is philosophy that came up with the concept of beings, which he calls forms, and highlighted their importance, first to natural philosophy and then to ethics, the things that do qualify as beings are inchoately revealed by mathematics as the raw materials that must be further processed by philosophy (mathematicians, to use Plato’s simile in the Euthedemus, do not invent the theorems they prove but discover beings and, like hunters who must hand over what they catch to chefs if it is going to turn into something useful, they must hand over their discoveries to philosophers). Even those forms that do not bear names of mathematical objects, such as the famous forms of beauty and goodness, are in fact forms of mathematical objects. The first chapter is an attempt to defend this thesis. The second argues that for Plato philosophy’s crucial task of investigating the exfoliation of the forms into the sensible world, including the sphere of human private and public life, is already foreshadowed in one of its branches, astronomy.