Publisher's Synopsis
As a contribution towards the International Space Year, the Space Agency Forum was formed which studied the properties of Venus and Mars and their relation to the Earth. The object was to better understand our planetary neighbours and how their characteristics may give insight into processes on Earth. The project was carried out at two COSPAR symposia. The first, entitled "Atmospheres of Venus and Mars" included sessions on the ionospheres, thermospheres, middle atmospheres, evidence for lightning, and atmospheric evolution. The results presented in this volume are based on measurements from various planetary spacecraft including Pioneer Venus, Galileo, Venera 15, Phobos 2 and Viking, as well as ground based observations from Earth. The second symposium, "Future Exploration of Mars", included sessions on science issues, data analysis and applications, approved missions, network missions, aeronomy and surface missions and future advanced missions.