Message from the ESO Director General
The signing of the ESO Convention in 1962 and the creation of ESO was the culmination of the dream of leading astronomers from five European countries, Belgium, France, Germany, the Netherlands and Sweden: a joint European observatory to be built in the southern hemisphere to give astronomers from Europe access to the magnificent and rich southern sky by the means of a large telescope.
The dream resulted in the creation of the La Silla Observatory near La Serena in Chile and eventually led to the construction and operation of a fleet of telescopes, with the 3.6-metre telescope as flagship. As Italy and Switzerland in 1982 joined ESO the construction of the New Technology Telescope, with pioneering advances in active optics, became possible, preparing the way for the next step: the construction of the Very Large Telescope. The VLT made adaptive optics and interferometry available to a wide community.
The decision to build a fully integrated VLT system, consisting of four 8.2-metre telescopes and providing a dozen foci for a carefully thought-out complement of instruments opened a new era in ESO’s history. The combination of a long-term adequately-funded instrument and technology development plan, with an approach where instruments are built in collaboration with institutions in the Member States, and with in-kind contributions in labour compensated by guaranteed observing time, has created the most advanced ground-based optical observatory in the world.
Today, in 2012, the original hopes of the five founding members have not only become reality but ESO has fully taken up the challenge of its mission to design, build and operate the most powerful ground-based observing facilities on the planet.
On the Chajnantor plateau in Northern Chile, together with North American and East Asian partners, ESO is developing the biggest ground-based astronomical project in existence, the Atacama Large Millimeter/submillimeter Array (ALMA). And ESO is preparing to build the world’s biggest eye on the sky, the European Extremely Large Telescope. Constantly at the technological forefront, ESO is ready to tackle new and even as yet unimaginable territories of scientific discovery.
These achievements have brought ESO many notable scientific breakthroughs, including the first image and direct spectrum of an exoplanet, a major stake in the discovery of the acceleration of the Universe and detailed studies of the supermassive black hole in the centre of the Milky Way.
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. It is undoubtedly one of the most exciting times to be an astronomer, and even more so to be an astronomer in an ESO Member State.
I would like to say a big thank you to all ESO staff, past and present — for it is your professionalism, ingenuity and passion that have made ESO the most productive observatory in the world.
On behalf of ESO, I would also like to thank the Council and Committee members and the former Directors General for leading the observatory to new heights in astronomy. It is a great honour for me to be at the helm of ESO today, during a revolutionary period.
The year 2012 is also a time to congratulate all our Member States. The five founding members have been joined by Denmark (1967), Switzerland (1982), Italy (1982), Portugal (2001), the United Kingdom (2002), Finland (2004), Spain (2007), the Czech Republic (2007), Austria (2009), and Brazil, who will become the 15th, as well as the first non-European, Member State after parliamentary ratification of the Accession Agreement signed in December 2010. The Member States have adhered to ESO’s courageous plans to lead ground-based astronomy, and offered us constant support and top-level people.
The scientific community is to be congratulated for keeping astronomy at the forefront of scientific research, as well as our supporters and international partners for believing in our ambitious projects. ESO owes its success in a large part to these collaborations!
To all of you, happy 50th anniversary!

Tim de Zeeuw, ESO Director General
Main events during 2012
- From 3–7 September 2012, ESO's Headquarters will host a scientific symposium to cover topics such as exoplanets, the Solar System, star formation and stellar evolution, cosmology and more.
- On the day of the anniversary, 5 October 2012, ESO aims to organise coordinated public events in the 15 Member States. Put together with the help of ESO's Science Outreach Network and Outreach Partner Organisations, the events will be an excellent way to connect the public at national venues directly with ESO's astronomy community and its breathtaking observatory sites in Chile.
- On 11 October 2012, ESO's Director General, Professor Tim de Zeeuw, and the Council President, Professor Xavier Barcons, will welcome Ministers from the Member States and the host country Chile, the ESO Council, representatives of ESO committees, past ESO Directors General, renowned astronomers and other people who have played key roles for ESO, at a gala anniversary event to take place in Munich.
- During the year, an anniversary exhibition will be on display at selected locations in the Member States. Interested venues may apply to host an exhibition via the contacts below.
- A documentary movie will be released on the anniversary day, together with a sumptuously illustrated book. The movie will also be released as episodes in ESO's popular ESOcast video podcast series. Adrian Blaauw's book, ESO's Early History, will be followed this year by a second history book written by Claus Madsen to complete the 50 years of ESO's history.
- The first Picture of the Week of every month in 2012 will be a special Then and Now feature, presenting ESO sites as they looked in the past and as they look today.
- For those who have witnessed ESO's historical voyage from the inside, either as members of staff or simply as visitors to our sites, we have expanded the Your ESO Pictures Flickr Group to include historical images. Please share your photo memories of ESO with us and everyone else by posting these "postcards from the past" to the group (ann12001).
- To mark the anniversary, some commemorative merchandise items have also been released in the ESOshop, also at bulk rates.
- Send anniversary messages to ESO on ESO's Facebook Page or on Twitter @ESO using the hashtag #ESO50years.
Calendar of anniversary events
If you wish to organise or dedicate an event to ESO’s anniversary and have it listed in the calendar, please write to us at information@eso.org
Fifty Highlights from Fifty Years
View the highlights here
Slideshow of Then and Now Pictures of the Week
Once a month during 2012, a special Then and Now Picture of the Week image will show how things have changed over the decades at the La Silla and Paranal observatory sites, the ESO offices in Santiago de Chile, and the Headquarters in Garching bei München, Germany. The following slideshow will be updated every month as we add more Then and Now photos.