GEOPHYSICS, ASTROPHYSICS, AND ASTRONOMY

This work is the result of contributions from 52 active researchers in geophysics, astrophysics and astronomy. We have followed a philosophy of directness and simplicity, while still allowing contributors flexibility to expand in their own areas of expertise. They are cited in the contributors’ list, but I take this opportunity to thank the contributors for their efforts and their patience. The subject areas of this dictionary at the time of this writing are among the most active of the physicalsciences.Astrophysics and astronomy are enjoying a new golden era, with remarkable observations in new wave bands (y-rays, X-rays, infrared, radio) and in new fields: neutrino and (soon) gravitational wave astronomy. High resolution mapping of planets continuously yields new discoveries in the history and the environment of the solar system. Theoretical developments are matching these observational results, with new understandings from the largest cosmological scale to the interior of the planets. Geophysics mirrors and drives this research in its study of our own planet, and the analogies it finds in other solar system bodies. Climate change (atmospheric and oceanic long-timescale dynamics) is a transcendingly important societal, as well as scientific, issue. This dictionary provides the background and context for development for decades to come in these and related fields. It is our hope that this dictionary will be of use to students and established researchers alike. It is a pleasure to acknowledge the assistance of Dr. Helen Nelson, and later, Ms. Colleen McMillon, in the construction ofthis work. Finally, I acknowledge the debt I owe to Dr. C.F. Keller, and to the late Prof. Dennis Sciama, who so broadened my horizons in the subjects of this dictionary.