A twilit display

After sunset a partially cloudy sky can cause a beautiful show of colours. In the foreground of this image some of the ESO-operated Auxiliary Telescopes for the Very Large Telescope (VLT) are visible. The VLT is based at the Cerro Paranal site in the Atacama Desert of northern Chile. It is the world's most advanced optical instrument, consisting of four Unit Telescopes with main mirrors of 8.2 metres diametre each, and four smaller Auxiliary Telescopes.