New Extragalactic Perspectives in the New South Africa

The date: September 30, 1880 The place: A private observatory in Hastings-on-Hudson Profession of the observer: A medical doctor The instrument: An l1-inch Clark refractor. The significance of that night marked one of the truly great turning points in the development of astronomical techniques: Dr Henry Draper, a wealthy New York medical doctor, had secured the first photograph of a nebula: a 51-minute exposure on a dry gelatinobromide plate showing the wispy nebulosity of the Orion Nebula. By March 1882, Draper had secured an exposure of 137 minutes, showing far richer detail of both bright and dark features. The rest is histapy. The photographic era heralded in a universe where hints of the presence of cosmic dust were strongly alluded to: from star-forming regions such as Messier 17, to the Horsehead Nebula in Orion, to the striking dark finger in the Cone Nebula, to the magnificent dark bands in the plane of our Milky Way. "Historically, astromomers from the very beginning have been afraid of dust.

Inhalt

Changing perceptions of the morphology and dust content in galaxies.- How cold could galaxies be?.- Temperature fluctuations and very cold dust.- The interstellar medium as observed by COBE.- Molecular gas in spiral galaxies.- Cold dust signatures on SNR gamma ray spectra.- Optical and infrared images of galaxies: What's to be learned?.- Optical, IR and HI observations of a large complete cluster sample.- The relationship between near IR extinction and CO emission.- Extinction and dust column density in spiral disks from FIR vs UV-Optical comparison.- The effects of supergiants on the infrared light distribution in galaxies.- Reflections at the Registration Desk.- Distribution and Content of dust in overlapping galaxy systems.- Evolution and emission of cold, warm and hot dust populations in diffuse and molecular clouds.- Organics and ices in galactic dust.- Studies of NIR dust absorption features in the nuclei of Active and IRAS galaxies.- Tiny grains and large molecules in the Milky Way and other galaxies.- The role of UV observations in understanding dust and its morphology.- Studies of interstellar dust and gas with the far ultraviolet cameras and far ultraviolet imaging spectrograph space shuttle investigations.- High spatial resolution 50 and 100 micron KAO observations of infrared-bright galaxies.- Infrared photometry and dust absorption in highly inclined spiral galaxies.- The nature of interstellar dust in Local Group galaxies from observations of extinction and polarization.- Structure in the distribution of the dust and its impact on extragalactic studies.- Determination of the 3D dust distribution in spiral galaxies.- A 3D dust model for the Sombrero galaxy.- Doubling of the infrared flux from NGC1068: a circumnuclear dust torus?.- Resolving the faint galaxy excess with HST: Results from the Medium Deep Survey.- Spiral structure in galaxies: Competition and cooperation of gas and stars.- Color gradients in M99: Stellar populations or dust?.- Amplitude and shape of spiral arms in K'.- The bulge/disk connection in late-type spirals.- Dust in starburst galaxies: From the ultraviolet to the near infrared.- Near-infrared surface photometry of barred spiral galaxies.- Barred galaxies in the near-IR: Observations and dynamical implications.- Morphology and dynamics of a few giant galaxies with low surface brightness disks.- Secular evolution of galaxy morphologies.- Dusty disks and the structure of early-type galaxies.- Dust and gas in Local Group galaxies.- The nuclear regions of M31, M32 and M33 imaged by the Hubble Space Telescope.- Gas and dust in normal and active galaxies.- mm observations of IRAS galaxies: Dust properties, luminosity functions and contributions to the sub-mm background.- Mapping the cold dust in edge-on galaxies at 1.2mm wavelength.- Internal absorption in spiral galaxies using four colours.- Dust in galaxies: A far infrared perspective.- Search for cold molecular gas.- Galactic structure and morphology of the Milky Way from the TMGS.- Unveiling large-scale structures behind the Milky Way.- The distribution of dust and gas in elliptical galaxies.- The ionized gas in early-type galaxies.- HST imaging of the dust in kinematically distinct core ellipticals.- Dust and gas in the outer parts of galaxies.- Dust spectra of the Milky Way: Primordial molecular hydrogen and helium in the outer Galaxy.- Fundamental aspects of the ISM fractality.- The DM-HI connection.- Very cold gas and dark matter.- Constraints on the surface density of gas in outer galaxy disks from stability analyses.- The changing circumstellar environment of young stars.- Interstellar dust in the solar system.- Pre-stellar cores and the initial conditions for star formation.- Dust and Morphology of high redshift radio galaxies: Clues from scattering.- Dust obscured Quasars.- The opacity of low surface brightness galaxies and their contribution to Quasar absorption.- The morphology of massive, gas-rich low surface brightness galaxies.- 38 micron images of galaxies: The infrared luminosity.- Poster Papers.- Dust in early-type galaxies: New results on the wavelength dependence of the extinction.- New radiative transfer models of disc galaxies and the scale-length test for dust diagnostics.- The distribution of cold dust within the Galaxy.- Detection of extended dust in a radioquiet galaxy at redshift 2.38.- Extinction in the direction of the end-of-bar star formation region.- Sampling the bar population.- Chasing shadows in the TMGS.- Imaging the inner Galaxy.- Fabry-Perot imaging of dust grain processing in M82.- The HI content of a complete sample of Sa galaxies.- Massive galactic halos and dark matter: Unusual properties of neutrinos in the de Sitter Universe.- Dust in a radio galaxy at z=4.25.- Voyager observations of dust scattered starlight.- Dust and stars in the nuclear region of M51.- Gaseous and stellar responses to spiral perturbations detected in the NIR.- Attenuation and stellar population gradients in spiral galaxies.- FIR and CII emissions in NGC6946.- The composition of interstellar dust.- Dust in radio galaxies: Clues to activity.- Defining spiral structure in the flocculent galaxy NGC5055.- Where does dust absorb most light?.- On the angular-momentum transport in spiral and barred galaxies.- Dust, stars and nuclear activity in the centres of Sbc galaxies.- The polarizing properties of dust in NGC5128.- Concluding Thoughts.- Astronomy at the University of the Witwatersrand.- Eyes to the Future: An Interactive Panel/Audience Discussion.- Each Chairperson Reflects on their Session.- The Riddle.- 'Where dust is stars'.- The Participants.- The Colour Plates.