Auxiliary telescopes at Paranal Observatory, Cerro Paranal, Chile. These 1.8-metre telescopes are secondary telescopes for the Very Large Telescope (VLT). The VLT comprises four 8.2-metre mirror telescopes, the images of which combine to produce an image equal to that obtained by one 16 metre diameter mirror. This makes the VLT one of the most powerful telescopes in the world. The auxiliary telescopes allow observations while the main telescope is in use. The VLT is operated by the European Southern Observatory. It is at an altitude of 2600 metres in the Atacama Desert, one of the driest places on Earth. This provides the VLT with excellent viewing conditions.