The 10th ESLAB Symposium was held at Grossenzersdorf near Vienna on 10-13 June 1975 under the title 'The Scientific Satellite Programme During the Inter national Magnetospheric Study'. The Symposium was attended by an invited audience of 60 scientists from the ESA Member States, the United States, Japan, Canada and Austria. Following a report by the joint COSPAR-IUCSTP Special Working Group, the International Magnetospheric Study (lMS) is proposed as an international co operative enterprise of limited duration, having as its principal objective the achie vement of a comprehensive, quantitative understanding of the dynamical processes operating in the Earth's plasma and field environment. In order to accomplish this objective, it is thought to be necessary to carry out simultaneous measurements with nearly identical instrumentation at various points in space. These measurements will need to be made in combination with appropriate observations at or near the Earth's surface. Besides near-Earth observations by ground-based, rocket- and balloon-borne instrumentation, satellite investigations are expected to make an important contri bution to the IMS. A number of satellites assigned to magnetospheric research have recently been launched, or will be launched shortly, to be operational during the IMS. The European Space Agency has devoted two of its forthcoming scientific satellites - GEOS and ISEE-B - to magnetospheric and interplanetary research.

The 10th ESLAB Symposium was held at Grossenzersdorf near Vienna on 10-13 June 1975 under the title 'The Scientific Satellite Programme During the Inter national Magnetospheric Study'. The Symposium was attended by an invited audience of 60 scientists from the ESA Member States, the United States, Japan, Canada and Austria. Following a report by the joint COSPAR-IUCSTP Special Working Group, the International Magnetospheric Study (lMS) is proposed as an international co operative enterprise of limited duration, having as its principal objective the achie vement of a comprehensive, quantitative understanding of the dynamical processes operating in the Earth's plasma and field environment. In order to accomplish this objective, it is thought to be necessary to carry out simultaneous measurements with nearly identical instrumentation at various points in space. These measurements will need to be made in combination with appropriate observations at or near the Earth's surface. Besides near-Earth observations by ground-based, rocket- and balloon-borne instrumentation, satellite investigations are expected to make an important contri bution to the IMS. A number of satellites assigned to magnetospheric research have recently been launched, or will be launched shortly, to be operational during the IMS. The European Space Agency has devoted two of its forthcoming scientific satellites - GEOS and ISEE-B - to magnetospheric and interplanetary research."

OPENING ADDRESS XI LIST OF PARTICIPANTS XV SESSION 1 THE ATMOSPHERE AND IONOSPHERE BELOW 150 km L. Thomas SOME OUTSTANDING PROBLEMS IN THE NEUTRAL AND IONIZED ATMOSPHERE BETWEEN 60 AND 150 km ALTITUDE 3 Peter M. Banks HIGH-LATITUDE IONOSPHERE-ATMOSPHERE INTERACTIONS (Abstract) 19 V. Domingo SOLAR RADIATION VARIATION AND CLIMATE 21 R. Bernard MAREES ET ONDES PLANETAIRES DANS LA BASSE THERMOSPHERE ET LA HAUTE MESOSPHERE 43 Michel Blanc and Paul Amayenc CONTRIBUTION OF INCOHERENT SCATTER RADARS TO THE STUDY OF MIDDLE AND LOW LATITUDE IONOSPHERIC ELECTRIC FIELDS 61 SESSION 2 THE OZONOSPHERE T. M. Donahue BASIC PROCESSES IN THE STRATOSPHERE AND THE MESOSPHERE (Abstract) 93 VI TABLE OF CONTENTS Ivar S. A. Isaksen CHEMICAL MODELS OF THE NEUTRAL ATMOSPHERE 95 M. Ackerman MEASUREMENTS OF MINOR CONSTITUENTS IN THE STRATOSPHERE 107 A. Vidal-Madjar, R. G. Roble, W. G. !iankin,G. Artzner, R. M. Bonnet, P. Lemaire, and J. C. Vial HIGH-RESOLUTION ATMOSPHERIC EXTINCTION MEASUREMENTS FROM THE FRENCH EXPERIMENT ON BOARD THE NASA SPACECRAFT OSO-8 117 M. Anderegg, J. E. Beckman, A. F. M. Moorwood, H. H. Hippelein, J. P. Baluteau, E. Bussoletti, A. Marten, and N. Coron HIGH-R~rOLUTION ATMQrPHERIC EMISSION SPECTROSCOPY AT 120 cm AND 535 cm WITH A RAPID-SCAN INTERFEROMETER AND 91 cm AIRBORNE TELESCOPE 129 Erwin Schanda, Joachim Fulde, and Klaus Kunzi MICROWAVE LIMB SOUNDING OF STRATOSPHERE AND MESOSPHERE 135 SESSION 3 METEOROLOGY IN THE IONOSPHERE AND STRATOSPHERE Hans-Jurgen Bolle CRITICAL CLIMATE PARAMETERS AND THEIR MONITORING FROM SPACE 149 R. J. Murgatroyd, A. O'Neill, and S. A.