We present results from a Chandra survey of 11 nearby, face-on spiral galaxies. 24 observations totaling 900 ks of new and archival Chandra data reveal more than 1000 X-ray point sources associated with the galaxies, diffuse emission, and hundreds of serendipitous sources. We discuss source populations and luminosity functions and show that the

We have compiled a database of Chandra-HRC snapshot images covering most of the M31 disk. The database consists of 5 HRC fields. All fields were observed at 16 different epochs covering a baseline of nearly 2 years. The merged image has a mean total exposure time of 17 ks. These data were analyzed to measure the mean fluxes of ~130 sources, most of

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V838 Mon has undergone one of the most mysterious stellar outbursts on record. The spectrum at maximum closely resembled a cool AGB star, evolving toward cooler temperatures with time, never reaching optically thin conditions or showing increasing ionization and a nebular stage. The latest spectral type recorded is M8-9. The amplitude peaked at ΔV

We present high-time-resolution spectroscopy of the non-eclipsing old nova V533 Herculis (N Her 1963). It is the second nova remnant affected by the `SW Sex syndrome'. A modulation of the equivalent width of the emission lines with a period of 23.33 min has been detected. This, together with the strong He IIλ4686 emission characteristic of magnetic

From the peak of a gravitational microlensing high-magnification event in the A component of QSO 2237+0305, which was accurately monitored by the Gravitational Lenses International Time Project collaboration, we derived new information on the nature and size of the optical V-band and R-band sources in the distant quasar. If the microlensing peak is