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Ice and Fire: Great Comets to Come was written because a special celestial event climaxes towards the end of 2013 – the arrival, fresh from the Oort Cloud, of Comet C/2012 S1 (ISON). By all predictions – even the most pessimistic ones – this comet is set to be one of, perhaps the most, dazzling comet seen in modern history and has the astronomical world buzzing with anticipation. Skywatchers have already been primed for C/2012 (ISON) earlier in 2013 with the apparition of another naked-eye comet, C/2011 L4 (PanSTARRS), and following C/2012 S1 (ISON) there is the prospect of 2012 K1 (PanSTARRS) reaching naked eye visibility in August 2014. Future bright cometary prospects are also discussed, taking into account the latest predictions. Examining the origin and nature of comets using examples of great comets from the past, this book sets the scene for the arrival of Comet C/2012 S1 and those following it over the next few years in the inner Solar System. Skywatchers and amateur astronomers can learn how to follow, observe and record comets. There is also a guide on how to keep abreast of the latest cometary discoveries and how to use a variety of reputable sources, including publications, websites, programs and apps to visualize and plan observations. The role of the amateur in cometary discovery also is featured, as well as details on how professional astronomers plan to get the most ‘science’ out of cometary apparitions, how and why professionals go about discovering comets, and upcoming plans to visit comets with space probes (and later, perhaps, human visits). Illustrations provide historic images of comets, images from space probes and images of the latest bright comets. Orbital plots and easy-to-follow sky charts are also included. This book is a unique guide that sets the scene by giving a comprehensive history of comets and examples of great comets throughout history and informs the reader about the nature and origins of this spectacular occurence. Expectations are fully covered by explaining not only what the regular person can expect to see, but how amateur astronomers can plan observations and what steps the professionals are taking to ‘get the most science’ from this exciting event.

What are these graceful visitors to our skies? We now know that they bring both life and death and teach us about our origins. Comet begins with a breathtaking journey through space astride a comet. Pulitzer Prize-winning astronomer Carl Sagan, author of Cosmos and Contact, and writer Ann Druyan explore the origin, nature, and future of comets, and the exotic myths and portents attached to them. The authors show how comets have spurred some of the great discoveries in the history of science and raise intriguing questions about these brilliant visitors from the interstellar dark. Were the fates of the dinosaurs and the origins of humans tied to the wanderings of a comet? Are comets the building blocks from which worlds are formed? Lavishly illustrated with photographs and specially commissioned full-color paintings, Comet is an enthralling adventure, indispensable for anyone who has ever gazed up at the heavens and wondered why. Praise for Comet "Simply the best." —The Times of London "Fascinating, evocative, inspiring." —The Washington Post "Comet humanizes science. A beautiful, interesting book." —United Press International "Masterful . . . science, poetry, and imagination." —The Atlanta Journal & Constitution

Comets are small bodies, but of great cosmic relevance. Given its pristine nature, they may preserve valuable and unique information on thechemical and physical processes that took place in theearly solar system, and that may be occurring in the formation of other planetary systems. They might have even played a very important role in the origin of life on Earth. Beyond that, since ancient times comets have inspired awe, superstition, and also curiosity anddebate. Their sudden apparitions challenged the long-held view of the immutability of the heavens, which triggered a long debate on whether comets had a heavenly or terrestrial nature. Therefore, comets have a prominent role in the history of scienti?cthought, that goes back to the most ancient civilizations. The last apparition of comet Halley in 1986 was a landmark since it arouse a great expectation in the scienti?c community and in the public at large. For the ?rst time, a ?otilla of spacecrafts visited a comet. Agreat number of popular and technical books were written on Halley, and comets in general, around the mid-eighties. The interest in comets never subsided after Halley’s passage which is re?ected in the large volume of printed material on these bodies. I have taken the challenge to write a new book on comets that summarizes most of the recent advances on thesubject, including my own workdeveloped during the last 25 years.