La Silla

In this photograph, three telescopes are portrayed, all looking very different from each other. To the right of the water tanks is the ESO New Technology Telescope (NTT), which had its first light on 23 March 1989. This 3.58-metre telescope was the first ever to have a computer-controlled main mirror, which could adjust its shape during observations to optimise image quality. The octagonal enclosure housing the NTT is another technological breakthrough, ventilated by a system of flaps that makes air flow smoothly across the mirror, reducing turbulence and leading to sharper images.

To the right of the NTT is the Swiss 1.2-metre Leonhard Euler Telescope, which has a more traditional dome-shaped enclosure. It is operated by the Geneva Observatory at the Université de Genève in Switzerland, and had its first light on 12 April 1998. It is used to search for exoplanets in the southern sky; with its first discovery being a planet in orbit around the star Gliese 86 (see eso9855). The telescope also observes variable stars, gamma-ray bursts and active galactic nuclei.

In the foreground on the right is a building nicknamed the sarcofago (sarcophagus). This houses the TAROT (Télescope à Action Rapide pour les Objets Transitoires, or Rapid Action Telescope for Transient Objects), which started work at La Silla on 15 September 2006.

This is the present-day photograph from the Then and Now Picture of the Week, Three Very Different Telescopes at La Silla.