A new prime focus corrector for the WEAVE project for the William Herschel Telescope is being produced. The corrector consists of six lens elements, the largest being 1.1 m in diameter. It also incorporates an Atmospheric Dispersion Corrector. Testing procedures for the WEAVE prime focus corrector lens elements are described here. Critical issues

Eine der rätselhaftesten astronomischen Entdeckungen der letzten Jahre waren die seltsamen Helligkeitsschwankungen des Sterns KIC 8462852 in den Daten des Weltraumteleskops Kepler. Neue Beobachtungen zeigen, dass diese Variationen von der Absorption durch feinen Staub herrühren, der sich vermutlich von Planetesimalen nahe dem Stern löst.

We present here SPECULOOS, a new exoplanet transit search based on a network of 1m-class robotic telescopes targeting the 1200 ultracool (spectral type M7 and later) dwarfs bright enough in the infrared (K-mag

The Sun is an ideal object for the development of Multi-Conjugate Adaptive Optics (MCAO) since solar structure provides multiple "guide stars" in any desired configuration. Current MCAO systems imply a number of wavefront sensors, each of them sensing an area of the Sun. The plenoptic camera is a novel concept for wavefront sensing, capable of

The instrument FRIDA (inFRared Imager and Dissector for Adaptive optics) is an integral field spectrograph (near infrared) operating at the wavelength range of 0.9 to 2.5um with imaging capability for being used at the Nasmyth B platform of the Gran Telescopio de Canarias (GTC). FRIDA is a collaborative project led by the Instituto de Astronomía

Bars are common galactic structures in the local universe that play an important role in the secular evolution of galaxies, including the Milky Way. In particular, the velocity distribution of individual stars in our galaxy is useful to shed light on stellar dynamics, and provides information complementary to that inferred from the integrated light