Cospar's executive director

Cospar's executive director

2. NEWS FROM COSPAR the illustrious Institut de France. The venue, which was built by Cardinal Mazarin and also hosts the world famous Academia Fran...

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2.

NEWS FROM COSPAR

the illustrious Institut de France. The venue, which was built by Cardinal Mazarin and also hosts the world famous Academia Francalse, provided the perfect atmosphere of dignity for a meeting of intense scientific debate and appreciation of Stan's outstanding scientific achievements. The credit for an excellent local organization goes entirely to Isaac Revah, Stan's successor in office, and CaSPAR's Associate Director Aaron Janofsky, who ensured that the meeting ran smoothly. The scientific organizers (G. Haerendel and D. Breitschwerdt) were particularly pleased that all the invited speakers immediately accepted their invitations to attend and to contribute.

2.1. COSPAR'S EXECUTIVE DIRECTOR Professor Stanislaw Grzedzielski retired as Executive Director of CaSPAR on 31 January 2001. Before taking up his position at CaSPAR, in July 1993, he had served for many years as Director of the Centre for Space Research of the Polish Academy of Sciences, and he was active in a number of ICSU bodies (IAU, IUGG/IAGA and SCaSTEP). He is returning to Poland to continue his scientific career, after 71f2 years at the CaSPAR helm. Professor Grzedzielski brought a wealth of valuable experience to CaSPAR and provided excellent, stable leadership over the years. This was celebrated on 23 January with a special Colloquium held in his honour in Paris.

(Report by D. Breitschwerdt and G. Haerendel)

The meeting started with an opening address by the CaSPAR President, Gerhard Haerendel, who also chaired the morning sessions. The first part was devoted to the Local Bubble and the local inter-stellar medium (L1SM), and the first talk - by D. Breitschwerdt (MPE Garching) - set the stage for the connection between the heliosphere and the L1SM. After summarizing key observations of the local clouds that surround the solar system, and of the Local Bubble, a region of 200 parsecs in diameter filled with dilute gas radiating in the X-ray part of the spectrum, in which both the clouds and the heliosphere are embedded, key problems were outlined: why is the pressure in the local clouds more than five times less than in the Local Bubble? Where do the local clouds originate? Why is He in the local cloud overionized with respect to H? Why can the spectrum of the Local Bubble not be fitted by a single hot plasma in collisional ionization equilibrium? Tentative answers were: (i) the clouds could be the result of an instability caused by the interaction between the Local Bubble and the neighbouring Loop I bubble, (ii) the Local Bubble plasma is not in ionization equilibrium and can therefore have a lower temperature and pressure. In the following talk by B. Wood (University of Colorado) a detailed report on the structure and topography of the clouds in the L1SM was given (so-called astronephography). Observations of absorbing intervening matter towards nearby stars reveal not only the 3D spatial structure of warm gas, but also its LSR velocity. We know that the local interstellar cloud (L1C) and the neighbouring G cloud have velocities of about 25 km/s.

On 23 January 2001, an international one day colloquium, entitled 'The interstellar environment of the heliosphere', was held in honour of CaSPAR's leaving Executive Director Stanislaw Grzedzielski on the premises of

An interesting new result was the possible deceleration of clouds as they sweep over the heliosphere, with no plausible mechanism as yet to hand. The solar system would eventually leave the L1C within less than 3000 years, as

The new Executive Director is Dr Isaac Revah. Dr Revah retired at the end of 1997 from the CNES (Centre National d'Etudes Spatiales) and, subsequently, worked at the French Academy of Sciences as Scientific Adviser to the Foreign Secretary where he was responsible for relations with the main international scientific academies (USA, China, Russia, Canada, India, Israel, Japan... ). Between 1984 and 1997, he held various responsibilities at CNES including Director of Programmes, Director of Environment and Director of External Relations. Before that, his scientific career as an ionospheric researcher, using meteor radar observations, was reoriented to remote sensing of environmental parameters of the Earth's atmosphere and of the vertical structure of planetary atmospheres. Between 1979 and 1984, he was Director of the CRPE (Centre de Recherche en Physique de l'Environnement Terrestre et Planetalre) - a joint laboratory of CNRS and CENT (Centre National d'Etudes des Telecommunications).

2.2. COSPAR COLLOQUIUM ON THE INTERSTELLAR ENVIRON· MENT OF THE HELIOSPHERE IN HONOUR OF STANISLAW GRZEDZIELSKI ON HIS RETIREMENT

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