ESO & Chile — A scientific and cultural bridge


A spectacular fiery sunset at Paranal. ESO's VLT platform can be seen in silhouette on the left of the picture, high on the peak of Cerro Paranal.

Credit: ESO/B. Tafreshi (

Chile was the first of ESO’s two host nations (Germany became the second in 1980).

On 6 November 1963 the Government of Chile and the European Southern Observatory (ESO) agreed to site ESO’s astronomical observatory in Chile. This was the start of more than 50 years of working together, and forging an important cultural link between Chile and Europe. Many ground-breaking discoveries have been made at ESO’s observatories and Chilean scientific and technological prowess has developed in step with the advances in astronomy and its associated technologies in ESO’s Member States.

Most importantly, this association has opened up an exciting path into the future — for the benefit of Chile and the ESO Member States, and for the benefit of science and technology in general.

The ESO – Government of Chile Joint Committee

Since 1996, the Chilean astronomical community has had preferential access to observing time on ESO telescopes. Under this agreement, the ESO - Government of Chile Joint Committee was established for the development of astronomy and scientific culture.

This fund finances postdoctoral fellowships and positions for astronomy professors at Chilean universities, infrastructure development, conferences, training for science teachers at primary and secondary level, and astronomy outreach programmes for the general public.


ESO’s Representative in Chile

The Office of the ESO Representation in Chile acts for ESO’s Director General in all matters, including relations with the Chilean authorities, and with the diplomatic missions representing ESO member states. It coordinates ESO's political and legal interests in Chile and promotes a positive relationship between ESO and Chile. Most of the units in ESO are involved in this work in some way.

ESO and Chile today

ESO’s engagement with Chile is a close and fruitful collaboration on many levels, across government, universities, science institutes and industry.

The ESO office in Santiago is an active centre for the education of new generations of researchers, and promotes collaboration and exchanges between European and Chilean institutions. The Chilean astronomical community has preferential access to a percentage of observing time on ESO telescopes, and ESO contributes to the development of astronomy in Chile through the funds managed by the ESO–Government of Chile Joint Committee and the ALMA CONICYT Joint Committee. ESO also undertakes cooperation programmes in the regions where the observatory sites are located and promotes natural conservation and awareness of the local heritage.

Chile has made major contributions to astronomy in this past half century, by providing access to its dark and clear skies and very attractive conditions for the establishment of world-class international observatories. Chile’s own scientific and technological capabilities have also grown impressively, making Chilean scientists and engineers very valuable partners for ESO. ESO’s facilities in Chile have provided numerous opportunities for the involvement of Chilean industry, engineering and science.

A history of success

Discussions about a “European Southern Observatory” began in 1953 and by 1962 it was clear that sites in Chile offered promising conditions. The first ESO Director General, Otto Heckmann, first visited Chile in May 1963. The Chilean authorities and academia were quick to recognise the importance of Heckmann’s visit, and less than six months later, the Convenio, or Agreement, between Chile and ESO was signed.

Construction of the La Silla Observatory began in 1965 and the first ESO telescope was installed soon after. La Silla subsequently acquired several other telescopes, the largest of which were the 3.6-metre telescope (which began operations in 1976), and the 3.5-metre New Technology Telescope (first light in 1989) as well as a 15-metre submillimetre antenna.

La Silla was inaugurated on 25 March 1969 in the presence of the Chilean President Eduardo Frei Montalva and the Swedish Education Minister Olof Palme.

In 1987, the ESO Council approved the project to build the VLT, an array of four Unit Telescopes equipped with 8.2-metre diameter mirrors. The aim was to at construct the most advanced ground-based observing facility for optical and near-infrared astronomy.

In 1990 a donation of land by the Chilean government saw Cerro Paranal selected as the site for the new telescopes. The Paranal Observatory was inaugurated on 5 March 1999 in the presence of President Eduardo Frei Ruiz-Tagle, and it has completely fulfilled its promise. In light of these decisions, the 1963 agreement was amended and significantly expanded in scope, committing ESO to active support of the development of Chilean astronomy and establishing the current level of partnership between ESO and Chile. The new agreement was signed in December 1996.

In 1997, ESO agreed to work with the US National Radio Astronomy Observatory on a major project in millimetre/submillimetre astronomy. The result is ALMA, an array of 66 antennas located on the Chajnantor Plateau. A partnership between ESO, North America and East Asia, in collaboration with Chile, it is the largest astronomical project in the world so far. ALMA was inaugurated by President Sebastián Piñera on 13 March 2013.

In 2014, the green light was given for ESO to take the next big step — to build the 39-metre Extremely Large Telescope (ELT).

Prof. O. Heckmann (ESO Director General 1962-1969) in front of the ESO 1-metre Schmidt telescope. Credit: ESO/S. Laustsen

The ESO Council of December 1996 at Paranal. It attended the inauguration ceremony with many other guests, among them the president of the Republic of Chile and the King of Sweden. Credit: ESO/H.H.Heyer

President of Chile at the time, Sebastian Piñera, among the huge antennas of ALMA, on the day of the telescope's inauguration. Credit: ESO

"A window to the Universe" is one of the five permanent exhibitions installed at the Museum of the Atacama Desert (MDA). This exhibition was designed and donated by ESO as a contribution to the Region of Antofagasta. Credit: ESO

"The Sky in our Hands (El Cielo en Nuestras Manos) is an educational activity offered by the Cruz del Sur public observatory (Southern Cross Observatory). The tour is supported and financed by ESO, through the ESO–Chilean Government Joint Committee 2009. Credit: Southern Cross Observatory/ESO/R.Marin