Some observations suggest that quiescent solar prominences can be considered as composed by small-scale loops, or fibrils, which are stacked one after another in both the vertical and horizontal directions. In a previous work we studied, in Cartesian geometry, the propagation of fast MHD waves in a two-dimensional magnetostatic model representing

The soft X-ray transient (SXT) XTE J1859+226 has been optically monitored from Tenerife using the IAC-80 and OGS 1m telescopes since its outburst on 1999 Oct 10 (see IAUC 7274, 7279). This R-band CCD photometry revealed a smooth decline of 0.017 mag/day for most of the next 8 months in parallel with that seen by the RXTE ASM, until two large ( ~2.5

Near-IR images of the prototype LINER/Seyfert type 1 galaxy NGC 1097 observed with the Very Large Telescope using adaptive optics disclose with unprecedented detail a complex central network of filamentary structure spiraling down to the center of the galaxy. The structure, consisting of several spiral arms, some almost completing a revolution

We present the discovery of 15 new T2.5-T7.5 dwarfs (with estimated distances ~24-93pc), identified in the first three main data releases of the United Kingdom Infrared Telescope (UKIRT) Infrared Deep Sky Survey. This brings the total number of T dwarfs discovered in the Large Area Survey (LAS) (to date) to 28. These discoveries are confirmed by

Lyα emitter (LAE) surveys have successfully used the excess in a narrowband filter compared to a nearby broadband image to find candidates. However, the odd spectral energy distribution (SED) of LAEs combined with the instrumental profile has important effects on the properties of the candidate samples extracted from these surveys. We investigate

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