Proceedings of IAU Symposium No. 95 held in Bonn, Federal Republic of Germany, 26-29 August 1980

This Symposium, the first devoted entirely to the measurement and the role of magnetic fields in the non-solar Universe, was held in Heidelberg, on June 19-23, 1989. The meeting began with review talks on magnetic phenomena near the solar photosphere, corona, and in stellar winds, since these nearby "laboratories," studied for many years, provide much of the prior knowl edge of magnetic effects in astrophysical plasmas. The Symposium contained presentations of considerable new work concerning the role of magnetic fields in accretion disks, bipolar outflows, and related magnetic phenomena in molecular clouds and star forming regions. Both observa tions and related theory of the large-scale magnetic fields in the Milky Way were covered, in addition to a session on the more general theme of magnetohydrodynamics of galactic magnetic fields. Dynamo mechanisms were discussed in considerable detail. It was apparent that recent observational data on polarized emission from external galaxies are now of sufficiently high quality that meaningful tests of large-scale field amplification, and of ideas on the origin of galactic magnetic fields, can be undertaken. Both new observations and numerical simulation work were described in the context of active galaxy nuclei, supernova remnants, radio source jets and extended lobes, and also in the environment of galaxy clusters. Recent large-scale computer simulations incorporating magnetic fields in star formation, radio source jets, and many other phenomena were presented, and much of this was very new."

More than a decade has passed since pulsars were discovered at Cambridge by J. Bell and A. Hewish. The past 13 years have seen ex tensive and at first rather hectic research, and a considerable amount of observational and theoretical knowledge has been accumulated. Looking back over one decade of pulsar research, it seems worth while to ask what the real impact of the detection was and if our view of the universe has changed as a result of this discovery. The excite ment of the first months and years has ebbed down considerably, with the result that pulsar research has become the task of a few scientists, working in small groups, scattered over many countries. As more and more knowledge was acquired, pulsars changed eventually from the bizarre pUlsing objects -- as they were considered in the beginning -- to more normal stars of astrophysical interest. Still, pulsars are the manifestation of matter in its most extreme form -- neutron star matter -- for which an equivalent can be found on earth only in the very nucleus of an atom. Neutron stars were predicted quite early in the history of modern astrophysics, and although many of their features were already known from theoretical studies, astro physicists were not sure if we had the slightest chance to actually "see" these objects. It therefore took some time after the historical detection paper of Hewish and coworkers before astronomers became con vinced that pulsars were neutron stars."

This Symposium, the first devoted entirely to the measurement and the role of magnetic fields in the non-solar Universe, was held in Heidelberg, on June 19-23, 1989. The meeting began with review talks on magnetic phenomena near the solar photosphere, corona, and in stellar winds, since these nearby "laboratories," studied for many years, provide much of the prior knowl edge of magnetic effects in astrophysical plasmas. The Symposium contained presentations of considerable new work concerning the role of magnetic fields in accretion disks, bipolar outflows, and related magnetic phenomena in molecular clouds and star forming regions. Both observa tions and related theory of the large-scale magnetic fields in the Milky Way were covered, in addition to a session on the more general theme of magnetohydrodynamics of galactic magnetic fields. Dynamo mechanisms were discussed in considerable detail. It was apparent that recent observational data on polarized emission from external galaxies are now of sufficiently high quality that meaningful tests of large-scale field amplification, and of ideas on the origin of galactic magnetic fields, can be undertaken. Both new observations and numerical simulation work were described in the context of active galaxy nuclei, supernova remnants, radio source jets and extended lobes, and also in the environment of galaxy clusters. Recent large-scale computer simulations incorporating magnetic fields in star formation, radio source jets, and many other phenomena were presented, and much of this was very new."