VLT Survey Telescope


The VLT Survey Telescope (VST) is the latest major telescope to be installed at ESO’s Paranal Observatory (eso1119). It is the largest telescope in the world designed for surveying the sky in visible light. This state-of-the-art 2.6-m telescope has joined the ESO VLT on Cerro Paranal, a perfect location for ground-based astronomical observations. It is equipped with an enormous 268-megapixel camera called OmegaCAM that is the successor of the very successful Wide Field Imager (WFI) currently installed at the 2.2-m MPG/ESO Telescope on La Silla.

Like the VLT, the VST covers a wide-range of wavelengths from ultraviolet through optical to the near-infrared (0.3 to 1.0 microns). But whereas the largest telescopes, such as the VLT, can only study a small part of the sky at any one time, the VST is designed to photograph large areas quickly and deeply.

With a total field view of 1°x 1°, twice as broad as the full Moon, the VST supports the VLT with wide-angle imaging by detecting and pre-characterising sources, which the VLT Unit Telescopes can then observe further.

The VST compriseds two mirrors, a primary mirror (M1) with a diameter of 2.61 m and a smaller secondary mirror (M2) with a 93.8 cm diameter. The telescope is also equipped with a single dedicated focal plane instrument: OmegaCAM. This huge (16k x 16k pixels) CCD camera was built by an international consortium of five institutions: Netherlands Research School for Astronomy (NOVA), Kapteyn Astronomical Institute, Universitäts-Sternwarte München, Astronomical Observatory of Padova and ESO.

Science with the VST

The VST is dedicated to survey programmes. With its state-of-the-art camera, the quality of its optics, and the exceptional seeing conditions of Paranal, VST is making important discoveries in a wide of areas of astrophysics and cosmology. In planetary science, the survey telescope aims to discover and study remote Solar System bodies such as trans-Neptunian objects, as well as search for extrasolar planet transits. The Galactic plane is also being extensively studied and is providing astronomers with data crucial to understand the structure and evolution of our Galaxy. Further afield, the VST is exploring nearby galaxies, extragalactic and intra-cluster planetary nebulae, and performing surveys of faint object and micro-lensing events. In the field of cosmology, the VST is targeting medium-redshift supernovae to help pin down the cosmic distance scale and understand the expansion of the Universe. The VST is also looking for cosmic structures at medium-high redshift, active galactic nuclei and quasars to further our understanding of galaxy formation and the Universe’s early history.

The VST project is a joint venture between the European Southern Observatory and the Capodimonte Astronomical Observatory (OAC), part of the Italian National Institute for Astrophysics (INAF). The Italian centre designed the telescope while ESO is responsible for the civil engineering works at the site.

The telescope became operational in 2011.

Science goals

Devoted to surveys. Milky way, extragalactic planetary nebulae, cosmology.

More about the VST

Live image

Follow the VST on this live image updated every hour during daytime. Click on it to enlarge.

Webcam | 21 Oct 2015 02:00 CEST
Last image before nightfall


Name: VLT Survey Telescope
Site: Cerro Paranal
Altitude: 2635 m
Enclosure: Compact optimised cylindrical enclosure
Type: Optical survey telescope
Optical design: Modified Ritchey-Chrétien Reflector with correctors
Diameter. Primary M1: 2.61 m
Material. Primary M1: Astro-Sitall
Diameter. Secondary M2: 0.938 m
Material. Secondary M2: Astro-Sitall
Mount: Alt-Azimuth fork mount
First Light date: 8 June 2011
Active Optics: Yes
Images taken with the VST: Link
Images of the VST: Link
Press Releases with the VST: Link