The lAU Symposium No. 78, "Nutation and the Earth's Rotation," was held in Y~ev, USSR, from 23 to 28 May, 1977. The Organizing Committee included E. P. Fedorov and R. O. Vicente (Joint Chairmen), W. Fricke, J. Kovalevsky, P. Melchior, N. Pariisky, M. Rochester, C. Sugawa, G. Wilkins and Ya. Yatskiv, who presided over the Local Organizing Com mittee. The meeting was sponsored by Commission 19 and co-sponsored by Commissions 4, 8, and 31. There were 114 registered participants from 14 countries. The main topics covered were as follows: the specification of nutation in the lAU system of astronomical constants; determination of forced nutation and nearly diurnal free polar motion from astronomical observations; expected use of lunar ranging data and long baseline interferometers for precise measurement of the nutation terms; models of the internal constitution of the Earth as the basis of a new theory of nutation; the effect of the ocean and liquid core on the rotation of the Earth; and the interaction between Earth tides and nutation.

This book describes how changes in the Earth's orientation are observed and computed in terms of tidal forcing and models of the Earth's interior.

Covering both astronomical and geophysical perspectives, this book describes changes in the Earth's orientation, specifically precession and nutation, and how they are observed and computed in terms of tidal forcing and models of the Earth's interior. Following an introduction to key concepts and elementary geodetic theory, the book describes how precise measurements of the Earth's orientation are made using observations of extra-galactic radio-sources by Very Long Baseline Interferometry techniques. It demonstrates how models are used to accurately pinpoint the location and orientation of the Earth with reference to the stars, and how to determine variations in its rotation speed. A theoretical framework is also presented that describes the role played by the structure and properties of the Earth's deep interior. Incorporating suggestions for future developments in nutation theory for the next generation models, this book is ideal for advanced-level students and researchers in solid Earth geophysics, planetary science and astronomy.

Planetary science is a truly multidisciplinary subject. The book deals with the atmospheres, surfaces and interiors of the planets and moons, and with the interplanetary environment of plasma and fields, as well as with asteroids and meteorites. Processes such as accretion, differentiation, thermal evolution, and impact cratering form another category of entries. Remote sensing techniques employed in investigation and exploration, such as magnetometry, photometry, and spectroscopy are described in separate articles. In addition, the Encyclopedia chronicles the history of planetary science, including biographies of pioneering scientists, and detailed descriptions of all major lunar and planetary missions and programs. The Encyclopedia of Planetary Sciences is superbly illustrated throughout with over 450 line drawings, 180 black and white photographs, and 63 color illustrations. It will be a key reference source for planetary scientists, astronomers, and workers in related disciplines such as geophysics, geology, and the atmospheric sciences.

Proceedings of IAU Symposium No. 48 held in Morioka, Japan, May 9-15, 1971

Published by the American Geophysical Union as part of the Geophysical Monograph Series, Volume 59. As part of the Nineteenth General Assembly of The International Union of Geodesy and Geophysics Symposium (IUGG) in Vancouver, Canada, Union Symposium U4, "Variations in Earth Rotation" was held August 18-19 1987. The Convenor was Dennis D. McCarthy, U.S. Naval Observatory with P. Paquet, Observatoire Royal de Belgique and M. G. Rochester, St. Johns University serving as co-convernors. In a session on internal structure of the Earth papers dealt with the geophysical effects on Earth rotation parameters. Mantle anelasticity increases the free core nutation (FCN) period by a few days. The period of the FCN and the amplitudes of the main nutation components are sensitive to the ellipticity of the core?]mantle boundary (CMB), and a non-hydrostatic increase of 400m in the flattening of the CMB is a possible explanation of the discrepancies from theory. An alternative suggestion rests on the subseismic description of the nutation spectrum of the stratified liquid core. Evidently new models will have to take into account contributions from the oceans, mantle anelasticity, non-hydrostatic pre-stress, CMB topography and internal core structure.