Introduction

Abstract

This handbook is a revision of the third edition of Allen’s Astrophysical Quantities [1], published in 1973, with further printings in 1976, 1981, and 1983. An attempt has been made to follow the original format, but the great advances in astronomical and astrophysical subfields have made this very difficult. More modern styles have been adopted, and many more subjects have been included. However, the original concept to present a rather concise, but still extensive, listing of astrophysical quantities has been retained. It is expected that scientists can use this book for quick information and also for key references to more detailed data sources.