La Silla Observatory
ESO's first observatory
The La Silla Observatory is located on the outskirts of the Chilean Atacama Desert, 600 km north of Santiago de Chile and at an altitude of 2400 metres. Like other observatories in this geographical area, La Silla is located far from sources of light pollution and, like the Paranal Observatory, home to the Very Large Telescope, it has one of the darkest night skies on the Earth. La Silla has been an ESO stronghold since the 1960s. Here, ESO operates two of the most productive 4-metre class telescopes in the world.
The 3.58-metre New Technology Telescope (NTT) broke new ground for telescope engineering and design and was the first in the world to have a computer-controlled main mirror (active optics), technology developed at ESO and now applied to most of the world's current large telescopes.
The La Silla Observatory is the first world-class observatory to have been granted certification for the International Organization for Standardization (ISO) 9001 Quality Management System.
The infrastructure of La Silla is also used by many of the ESO Member States for targeted projects such as the Swiss 1.2-metre Leonhard Euler Telescope, the Rapid Eye Mount telescope (REM) and the TAROT Telescope gamma-ray burst chaser, as well as more common user facilities such as the MPG/ESO 2.2-metre and the Danish 1.54-metre Telescopes. The 67-million pixel Wide Field Imager on the MPG/ESO 2.2-metre Telescope has taken many amazing images of celestial objects, some of which have now become icons in their own right.
A tour of the La Silla Observatory
Click on the image to take a Virtual Tour in and nearby La Silla.
Chile night time only! During the day the webcam shows the last frame before sunrise. The red letters indicate telescopes that are observing right now (T—the ESO 3.6-metre telescope, N— New Technology Telescope and D—the MPG/ESO 2.2-metre telescope). Please, see more on La Silla - All Sky Camera.
Visit the La Silla Observatory
- Journalists, science writers and producers, please see Media Visits
- Tourist, students and lay people, please see the Weekend Visits page
Science with the Telescopes at La Silla
With about 300 refereed publications attributable to the work of the observatory per year, La Silla remains at the forefront of astronomy. La Silla has led to an enormous number of scientific discoveries, including several "firsts". The HARPS spectrograph is the undisputed champion at finding low-mass extrasolar planets. It detected the system around Gliese 581, which contains what may be the first known rocky planet in a habitable zone, outside the Solar System (eso0722). Several telescopes at La Silla played a crucial role in linking gamma-ray bursts — the most energetic explosions in the Universe since the Big Bang — with the explosions of massive stars. Since 1987, the ESO La Silla Observatory has also played an important role in the study and follow-up of the nearest recent supernova, SN 1987A.
More about Science at La Silla
- Science with ESO Telescopes
- Some of the ESO Top 10 Astronomical Discoveries were done using telescopes on La Silla
More about La Silla Observatory
- More interesting facts are available on the FAQs page
- More images and videos are available in the ESO multimedia archive.
- Exhibition panels for download
- Read more on about this observatory on the La Silla Handout in PDF format
- For Scientists: for more detailed information, please see our technical pages
La Silla Observatory Timelapse
La Silla Trailer
Download the La Silla trailer in the video archive.
Decommissioned La Silla 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.