We compare the detailed distributions of H I, H alpha , and 150 nm far-UV (FUV) continuum emission in the spiral arms of M81 at a resolution of 9" (linear resolution 150 pc at 3.7 Mpc distance). The bright H alpha emission peaks are always associated with peaks in the FUV emission. The converse is not always true; there are many regions of FUV

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Comet Hale-Bopp has shown an extremely elevated level of dust activity during its apparition. We examine the dust activity of the comet, particularly the dust jets which were observed so frequently between discovery and perihelion + 5 months. Other results from observations carried out during the observing campaign have shown that the dust emission

We have obtained new narrowband CCD images, spatially resolved intermediate- and high-dispersion spectroscopic observations of the Ring Nebula (NGC 6720). These data reveal that the bright main nebula is not a real ring, but a closed shell. A prolate ellipsoidal geometry for this shell is inferred from the observed tilts in the [N II] velocity

The continuum and emission lines properties of a sample of 73 blazars is studied, investigating differences and similarities among normal low-polarization quasars (LPQ), radio-loud high polarized quasars (HPQ), and BL Lacertae objects (BLL). We found that at variance with LPQ, most HPQ have power law optical continua (fnu_{prop.to}νalpha^ ) with no

IAUC 6714 available at Central Bureau for Astronomical Telegrams.