by Ludwig Scheibe (TU Berlin), March 2025
Located in the Atacama Desert in Northern Chile as part of the Paranal Observatory, the Very Large Telescope (VLT) is one of the largest and most advanced optical telescope facilities in the world. It is operated by the European Southern Observatory ESO, and started operations in 1999.
The main instruments of the VLT are four individual optical and infrared telescopes with apertures of 8.2 metres each. Although they usually operate independently, they can be combined via interferometry to reach increased resolutions. There are also four smaller auxiliary 1.8m-telescopes.
The VLT hosts ESPRESSO, the flagship spectrograph of ESO and one of the world’s leading instruments for characterizing exoplanets with the radial velocity method, allowing observers to determine a planet’s mass very precisely.
Among the notable discoveries made using the VLT is 2M1207 b, the first exoplanet directly imaged exoplanet, published in 2004. Another example is Proxima Centauri b, the exoplanet around our nearest neighbor star, which was discovered in 2016 in large part using radial velocity measurements made with the VLT.
To learn much more about the VLT, including a large collection of pictures taken with it, visit the official VLT website.