ESO Survey Telescopes
Mapping the sky in the finest detail
Two new and powerful telescopes — the Visible and Infrared Survey Telescope for Astronomy (VISTA) and the VLT Survey Telescope (VST) — are operational at ESO’s Paranal observatory in northern Chile. They are arguably the most powerful dedicated imaging survey telescopes in the world and are hugely increasing the scientific discovery potential of the Paranal Observatory.
A Tour at Paranal Observatory
Click on the image to take a Virtual Tour in and nearby the VLT.
Visit Paranal Observatory
- Journalists, science writers and producers, please see Media Visits
- Tourist, students and lay people, please see the Weekend Visits page
Science with the Survey Telescopes
Many of the most interesting astronomical objects — from tiny, but potentially dangerous, near-Earth asteroids to the most remote quasars — are rare. Finding them is like looking for a needle in a haystack. The largest telescopes, such as ESO’s Very Large Telescope (VLT) and the NASA/ESA Hubble Space Telescope, can only study a minute part of the sky at any one time, but VISTA and the VST are designed to photograph large areas quickly and deeply. The two telescopes are currently performing a total of nine carefully designed surveys and will create vast archives of both images and catalogues of objects that will be harvested by astronomers for decades to come. The Survey Telescopes will have a vital role in preparing the way for future facilities such as the Extremely Large Telescope (ELT) and the James Webb Space Telescope (JWST).
The scientific goals of the surveys include many of the most exciting problems in astrophysics today, ranging from the nature of dark energy to the threat of near-Earth asteroids. Large teams of astronomers throughout Europe will conduct the surveys. Some of the surveys will cover most of the southern sky while others will focus on smaller areas.
Interesting objects discovered by the Survey Telescopes will form targets for detailed study both by the neighbouring VLT and by other telescopes on Earth and in space. Both Survey Telescopes are housed in domes close to the VLT and share the same exceptional observing conditions as well as the same highly efficient operational model.
Both VISTA and the VST will produce huge quantities of data — a single picture taken by VISTA has 67 megapixels and images from OmegaCam on the VST will have 268 megapixels. The two Survey Telescopes will produce far more data every night than all the other instruments on the VLT combined. Together the VST and VISTA will produce more than 100 Terabytes of data per year.
More about the ESO Survey Telescopes
- More interesting facts are available on the FAQs page
- More images and videos are available in the ESO multimedia archive.
- Read more on about this observatory on the Survey Telescopes Handout in PDF format
- For Scientists: for more detailed information, please visit the VST website and the VISTA website
ESO Survey Telescopes
Stars form in dense clouds of the interstellar medium, but even in these densest regions the pressure is comparable to the most tenuous vacuum created in a laboratory on Earth. In these clouds, the temperatures are below -200 degrees Celsius.
The skies over the ESO sites in Chile are so dark that on a clear moonless night it is possible to see your shadow cast by the light of the Milky Way alone.
The Paranal observatory site is so remote that everything needed must be brought in specially. The 60 000 litres of water that are used per day are delivered by truck from Antofagasta.