• J. V. Evans


The Symposium on Planetary Atmospheres and Surfaces, held at Woods Hole, Massachusetts, August 11–15, 1969, was the successor to an earlier symposium held in May 1965 in Puerto Rico, whose proceedings were published in vol. 69D, no. 12 (1965) of Radio Science. Both meetings were organized through the initiative of Commission II of URSI (Radio Propagation in Non-Ionized Media), who secured the sponsorship of URSI (International Union of Radio Science), the IAU (International Astronomical Union), and, in the case of this Symposium, of COSPAR (Committee on Space Research). Financial support for the Symposium was provided by URSI.

Whereas the earlier symposium dealt almost exclusively with the results of radar and radio astronomy, the most exciting new results since then have been obtained by space research. Thus, in planning the new symposium the organizers sought to bring together workers in the two fields. This was deemed particularly important in the study of the moon, since it is now possible to determine how well radio and radar astronomy succeeded in describing the properties of the lunar surface prior to its physical investigation by use of landed vehicles. Based on such a comparison, one may be able to apply the radio techniques to planetary surface investigations with greater confidence. Accordingly, four sessions of the symposium were devoted to the moon, permitting extensive reviews of the results secured by the Ranger, Orbiter, and Surveyor vehicles. The organizers and chairmen of these sessions were: Dr. H. Masursky, U. S. Geological Survey; Dr. G. H. Pettengill, Arecibo Ionospheric Observatory; Dr. L. D. Jaffe, Jet Propulsion Laboratory; and Prof. Z. Kopal, University of Manchester. A highlight of the meeting was some preliminary reports on the results of the Apollo experiments. From the talks and lively discussion it would seem that, although there are matters of detail to be ironed out, we now have a good physical description of the surface properties of the moon and recognize that both external and internal processes have played a part in shaping them. However, considerable work has to be done before we may hope to understand the full history of the moon and its origin.