We present TAURUS Fabry-Perot velocity data in Hα emission of the disc of the grand design spiral M 100 (NGC 4321). We have studied the emission spectra of the 200 H ii regions most luminous in Hα, calibrated in luminosity using photometric Hα imaging from the literature. The emission spectra of individual H ii regions were fitted using one or more

Simultaneous modeling of the line and continuum emission from the nuclear region of the Circinus galaxy is presented. Composite models that include the combined effect of shocks and photoionization from the active center and from the circumnuclear star-forming region are considered. The effects of dust reradiation, bremsstrahlung from the gas, and

A ring-diagram analysis technique has been applied to a region of the Sun of about 15 deg^2 area close to the disk center at dates chosen for several solar rotations in 1996: April 5, May 1, May 28, June 27, July 23, August 20, August 21, and September 18. The horizontal velocity flows inferred directly beneath the solar surface have thus been

We estimate the typical spectrum of spatial fluctuations of intensity due to the penumbral filaments. High angular resolution continuum images are used (cut-off frequencies equivalent to 0.28" wavelength of about 5257 Å). The amplitude of the observed spectra follows the modulation transfer function of our optical system. In other words, the

Results from a photometric search for extrasolar planetary transits across the eclipsing binary CM Dra are presented. The TEP (Transits of Extrasolar Planets) network has observed this star since 1994, and a lightcurve with 617 hours of coverage has been obtained. The data give a complete phase coverage of the CM Dra system at each of the 3 years

Since the launch of SOHO, the Solar Heliospheric Orbital Observatory, the helioseismic observations are nearly uninterrupted. The GOLF instrument (A. Gabriel et al., 1997) measures the mean velocity integrated over the disk. The autocorrelation function of this velocity shows two main features: Firstly, the initial decrease of the peak amplitudes