The familiar ring around the moon is an example of an atmospheric halo, which is a signature of ice crystals in the air, though the focus here is on odd radius halos. The shape of the ice crystals responsible is only just becoming understood, and is determined by angle x, which has yet to be identified. Tape and Moilanen (their affiliations are not stated), discuss the phenomenon and its possible causes. Some of the material is accessible to lay readers with some scientific background, and some requires college-level mathematics. One of their goals is to encourage the former to notice atmospheric halos--for example different sized ones around the sun--and to marvel at the mystery they present as well as their beauty. Annotation :2006 Book News, Inc., Portland, OR (booknews.com).

Very Good,No Highlights or Markup,all pages are intact.

Many nations conduct research and engage in other scientific activities on our frozen continentâ€"Antarctica. Each year the U.S. National Committee for the Scientific Committee on Antarctic Research (SCAR) compiles a book that includes these nations' reports of scientific pursuits undertaken by their citizens in Antarctica during the previous austral summer and of planned activities for the next season. This book details the activities that occurred in 1990 and is of particular value to policymakers and scientists throughout the world who are planning Antarctic programs.

A 24-hour practical guide to skywatching.

We live in a world of optical marvels - from the commonplace but beautiful rainbow, to the rare and eerie superior mirage. But how many of us really understand how a rainbow is formed, why the setting sun is red and flattened, or even why the sky at night is not absolutely black? This beautiful and informative guide provides clear explanations to all naturally occurring optical phenomena seen with the naked eye, including shadows, halos, water optics, mirages and a host of other spectacles. Separating myth from reality, it outlines the basic principles involved, and supports them with many figures and references. A wealth of rare and spectacular photographs, many in full color, illustrate the phenomena throughout. In this new edition of the highly-acclaimed guide to seeing, photographing and understanding nature's optical delights, the authors have added over 50 new images and provided new material on experiments you can try yourself.