Context. The BL Lac object S5 0716+714, a highly variable blazar, underwent an impressive outburst in January 2015 (Phase A), followed by minor activity in February (Phase B). The MAGIC observations were triggered by the optical flux observed in Phase A, corresponding to the brightest ever reported state of the source in the R-band. Aims.The

Comet C/2000 WM1 (LINEAR) was observed at ESO when it had its closest approach to the Earth at the beginning of December 2001 (geocentric distance: 0.32 AU). The aim of the observations was the characterization of the solid component of the coma in order to better understand the origin and the correlation between most aspects of this component. The

In a search for the counterpart to the Fermi-LAT source 3FGL J0838.8-2829, we performed a multiwavelength campaign: in the X-ray band with Swift and XMM-Newton; in the infrared and optical with OAGH, ESO-NTT and IAC80; and in the radio with ATCA observations. We also used archival hard X-ray data obtained by INTEGRAL. We report on three X-ray

Single-epoch multifrequency data for the BL Lac objects OI 90.4 and 3C 66A, spanning radio through ultraviolet wavelengths, are presented, as well as other measurements relevant to intensity and spectral-shape variability. Both BL Lac objects exhibit spectral curvature in the infrared-to-ultraviolet region, a properity that is inferred to be usual

We present high resolution images and high dispersion spectra of the planetary nebula IC 4593. Benefiting from superb seeing (0″.4), the narrowband images reveal the existence of a complex system of collimated knots in the inner 15″ of the nebula.The knots, which morphologically resemble outward facing bow-shocks, are located at different position

We used extensive ground-based multisite and archival spectroscopy to derive observational constraints for a seismic modelling of the magnetic β Cep star V2052 Ophiuchi. The line-profile variability is dominated by a radial mode (f1 = 7.148 46 d-1) and by rotational modulation (Prot = 3.638 833 d). Two non-radial low-amplitude modes (f2 = 7.756 03