Context. BL Lacertae objects are variable at all energy bands on time scales down to minutes. To construct and interpret their spectral energy distribution (SED), simultaneous broad-band observations are mandatory. Up to now, the number of objects studied during such campaigns is very limited and biased towards high flux states. Aims: We present

Abstract image available at: http://adsabs.harvard.edu/abs/1976A&A....50..389M

We study the far-infrared emission properties of the nearby starburst galaxy NGC 253 based on IRAS maps and an ISOPHOT map at 180 μm. Based on the analysis of the light profiles, we have been able to identify three main structural components: an unresolved nuclear component, an exponential disk, and a kiloparsec-scale bar. In addition, we also

Narrow-band Hα+[NII] imaging and long-slit spectroscopy at intermediate resolution from [NeV] lambda3426 to [SIII] lambda9532 of the LINER galaxies NGC 4579 and 6500 are analysed. Both galaxies show circumnuclear emission, extending 2kpc from the nucleus of NGC 4579 in a loop structure and 1 kpc from the nucleus of NGC 6500 in a bright knot to the

We report spectral time series of the late O-type runaway supergiant HD 188209. Radial velocity variations of photospheric absorption lines with a possible quasi-period of ~6.4d have been detected in high-resolution echelle spectra. Night-to-night variations in the position and strength of the central emission reversal of the Hα profile occurring

Context. X-Shooter is the first second-generation instrument for the ESO-Very Large Telescope. It is a spectrograph covering the entire 300-2480 nm spectral range at once with a high resolving power. These properties enticed us to observe the well-known trans-Neptunian object (136199) Eris during the science verification of the instrument. The