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We present 24 μm and 70 μm images of a non-radiative shock in the Cygnus Loop supernova remnant, obtained with the Multiband Imaging Photometer on board the Spitzer Space Telescope. The observed emission is from dust grains heated in the post-shock region. The 70 μm to 24 μm flux ratio depends on the dust heating and the dust destruction rates, and thereby it is a sensitive tracer of the gas density and temperature in the shocked plasma. We model the dust emission and grain destruction in the post-shock flow, and find that the observed 70 μm to 24 μm flux ratios are produced for post-shock densities, nH∼2.0 cm-3 and electron temperatures of about 0.20 keV. We find that about 35% of the dust has been destroyed in the shock, and that non-thermal sputtering (i.e. sputtering due to bulk motion of the grains relative to the gas) contributes significantly to the dust destruction. [ABSTRACT FROM AUTHOR]

Cataclysmic variables are the nearest and most easily studied laboratories for understanding accretion onto compact objects. FUSE has provided the first significant sample of high resolution, high S/N spectra of such objects in the wavelength range 900–1183 Å. As expected, the FUSE spectra of most nova-like variables and dwarf novae in outburst show broad features associated with emission from the inner accretion disk. Detailed modeling has proven difficult, however, because the flux near the Lyman limit is higher than expected, indicating that the vertical structure of the disk differs significantly from that of normal stellar atmospheres of similar temperature and gravity. Wind features, due to OVI and CIII, are also evident in many systems, and in most cases are accompanied by fairly narrow lower ionization-state lines that are blue shifted by no more than a few 100 km s-1. These narrower features and the small number of systems with P-Cygni-like profiles suggest that most of the wind features observed with FUSE arise in material fairly near the disk surface, a picture quite different from that inferred from analyses of longer wavelength HST data. Dwarf nova systems in optical quiescence show FUV emission from the WD, which is heated by and cools after outbursts, and from the disk, and, surprisingly, at least in some cases, the hot spot. Here I will briefly illustrate the contributions FUSE has made to our understanding of cataclysmic variables, describe the quantitative state of the modeling, and suggest where we might go from here. [ABSTRACT FROM AUTHOR]

At this conference we have seen a wealth of new results on young supernova remnants, the supernovae that produce them, the environments that surround them, and the pulsars or more exotic compact objects that may be left behind. Great progress has been made through the combination of observations at wavelengths from radio through gamma rays—both from the ground and from space—with creative theoretical efforts and powerful computational models. Especially impressive are the many spectacular early results of X-ray observations from the Chandra and XMM-Newton missions. In this paper, we give a personal view of some of the highlights of the conference, colored by the perspective of almost six decades (three for each of us) of work on SNRs. [ABSTRACT FROM AUTHOR]