ESO celebrates 50 years of “Euro-astronomy”

Today the European Southern Observatory is celebrating its 50th anniversary. This article retraces the story of one of Europe's greatest laboratories, which came into being with CERN's support and assistance.


La Silla, June 1968. The three telescopes in the background are (from left to right): the Grand Prism Objectif (GPO, first light in 1968), the ESO 1 metre telescope (1966), and the ESO 1.5 metre telescope (1968). They have been decommissioned. The white dome closest to the viewer is the ESO 1 metre Schmidt telescope, which began work in 1971. Image: ESO/E. Maurice.

In the spring of 1953, in Leiden in the Netherlands, a group of astronomers including Walter Baade, Jan Oort, Adriaan Blaauw, Otto Heckmann and Jan Bannier (who was then President of CERN's Provisional Council) for the first time discussed the possibility of founding a European space observatory. The objective was to build it in the southern hemisphere where there were very few observatories with powerful telescopes.

Almost 10 years later, on 5 October 1962 -  exactly 50 years ago to the day!* - representatives of five European countries (Belgium, France, Germany, the Netherlands and Sweden) met in Paris to bring this project to life by signing the European Southern Observatory (ESO) Convention. ESO’s Convention was largely inspired by the CERN Convention, as the two organisations were similar and some of the ESO Council members were also members of the CERN Council. Indeed, ESO and CERN are still the two participating organisations of the same pension fund.

The following year, Otto Heckman, the then ESO Director-General, concluded an agreement with the Chilean government with a view to building the observatory 2,400 m above sea level on the La Silla site in the mountainous region of Chile’s Atacama Desert. November 1966 saw the commissioning of ESO’s first telescope, which had a diameter of 1 metre. 20 years later the Very Large Telescope (VLT), the world's largest optical telescope, was officially inaugurated.

La Silla, today. This photograph shows two new telescopes. The silver dome is that of the MPG/ESO 2.2 metre telescope, which has been in operation since early 1984. On the far left is the Danish 1.54 metre telescope, in use since 1979. Image: ESO/E. Maurice.

In 1970 ESO and CERN signed a collaboration agreement. This was quickly followed by the setting-up of the Telescope Division and the installation of ESO’s Sky Atlas Laboratory at CERN in Geneva. It wasn't until 1980 that all ESO’s departments were brought together at the present site in Garching, near Munich in Germany. And it is in Garching that the 50th anniversary celebrations are taking place today. As the current ESO Director-General Tim de Zeeuw proudly observed at the beginning of the year: “At the dawn of 2012, our 50th anniversary year, we are ready to enter a new era, one that not even the initial bold dreams of ESO’s founding members could have anticipated. Extremely large telescopes will seek to answer some of humanity’s most demanding questions. This is undoubtedly one of the most exciting moments for astronomers and especially for the astronomers of ESO’s Member States."

*CERN celebrated its 58th anniversary on 29 September this year.


ESO and its 15 Member States

1962: the five founding states, Belgium, France, Germany, the Netherlands and Sweden, sign the ESO Convention.
1967: Denmark becomes the sixth Member State.
1982: Switzerland and Italy become members of ESO.
2001: Portugal accedes to membership of ESO.
2002: the United Kingdom becomes the 10th Member State.
2004: Finland becomes a Member State.
2007: Spain and the Czech Republic accede to ESO.
2009: Austria signs.
2010: Brazil signs the accession agreement. It will soon become the first non-European Member State.


Don't miss the article devoted to ESO’s 50th anniversary in the latest edition of the CERN Courier. The article includes further details of the links between ESO and CERN.

ESO has made a documentary to celebrate its 50th anniversary: "Europe to the Stars — ESO's first 50 years of Exploring the Southern Sky". For more information and to watch the film click here.

More information on the history of ESO can be found in the book entitled "The Jewel on the Mountaintop", and in the illustrated publication "Europe to the Stars".


by Anaïs Schaeffer