We present high-time-resolution multicolour observations of the quiescent soft X-ray transient V404 Cyg obtained with ULTRACAM. Superimposed on the ellipsoidal modulation of the secondary star are large flares on time-scales of a few hours, as well as several distinct rapid flares on time-scales of tens of minutes. The rapid flares, most of which

We analyze a time series of high angular resolution magnetograms of quiet Sun Inter-Network (IN) magnetic fields. These magnetograms have a spatial resolution better than 0farcs5, a noise of some 20 G, and they have been obtained at the disk center during the minimum of the solar cycle. The IN regions show a typical unsigned flux density of the

The agreement with PPARC and NWO has ensured operational continuity of the ING, whilst, at the same time, providing additional time for Spanish astronomers. The IAC contribution consists of qualified staff, astronomers and engineers, plus an infrared imaging spectrograph for the WHT (LIRIS). The overall IAC contribution is equivalent to about half

We analyze the Hα emission line profiles of the HII region populations in three disc spiral galaxies and find evidence of wing features at 40-90 km/s from the central peak in a significant fraction of regions. We explain the wing features as due to a shell expanding inside the HII region, quantify the energy involved and present two possible

We report optical and near-infrared follow-up observations of GRB 011121 collected predominantly at ESO telescopes in Chile. We discover a break in the afterglow light curve after 1.3 days, which implies an initial jet opening angle of about 9°. The jet origin of this break is supported by the fact that the spectral energy distribution is

The Gravitational Lenses International Time Project (GLITP) collaboration observed the first gravitational lens system (QSO 0957+561) from 2000 February 3 to March 31. The daily VR observations were made with the 2.56-m Nordic Optical Telescope at Roque de los Muchachos Observatory, La Palma, Spain. We have derived detailed and robust VR light