CCD spectroscopic observations from [NeV] lambda3425A to [SIII] lambda9532A of the nucleus and circumnuclear region of the Seyfert 1 NGC 4253 are presented. The nucleus shows circumnuclear emission which is elongated 1.5 kpc to the north-east; the spectrum of this extranuclear emission is well fitted by HII region models with effective temperatures

We present optical photometry and spectroscopy of the nova-like variable V795 Her. The emission lines exhibit an extremely complex structure consisting of several time-variable emission and absorption components. We confirm the spectroscopic modulation of 0.1082d which we attribute to the orbital period of the system. The equivalent widths (EWs) of

The presence of giant shells or loops in giant H II regions is clear witness to the mechanical energy input from massive stars. Here we evaluate the impact that winds may have on the structure of giant nebulae and on their supersonic velocity dispersion. We follow the recent suggestion of Chu and Kennicutt to see whether a combination of a large

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We obtained K-band (2.0-2.5 micron) infrared spectra of the visually obscured superluminal source GRS 1915+105 on three different epochs of the year 1995, at times when it was detected as a hard X-ray source. The three spectra exhibit HI Br(gamma) (2.167 micron) and HeI (2.058 micron) emission lines. The spectral morphology, absolute magnitude, and

There is strong anticipation that the Leonid meteor shower could produce storm-level activity in 1998 and/or 1999. The well-documented Leonid outburst in 1996 and the more poorly observed one in 1994 have been taken by many observers to imply that a storm is imminent, This article explores the possible relationship between the 1996 outburst in