Observational Cosmology Proceedings of the 124th Symposium of the International Astronomical Union, Held in Beijing, China, August 25–30, 1986

The Symposium was held at the Great Wall Sheraton Hotel in Beijing, China in the period August 25-30, 1986. The decision to concentrate on the observational aspects of modern cosmology was taken in part because this conference has come in a period when there have been several international meetings on one aspect of modern cosmology, namely the early universe and its possible relationship to particle physics. While that approach is extremely exciting, it has the disadvantage that its connection with much of observational cosmology is very indirect. Thus there has been little opportunity to discuss critically the wealth of new data that are now becoming available which bear on the structure and evolution of the Universe but not always on its early history. This Symposium was planned to cover all aspects of observational cosmology, with only comparatively minor excursions into theory. Nearly 200 participants attended from 21 countries. A total of 26 invited papers and 73 contributed papers were given. This meant that everyone worked hard and long from 9 A.M. to about 5:30 P.M. for five of the six days of the conference. In addition to oral contributions, space was made available for poster papers and 56 of these were available for study for the duration of the conference.