ESO Announcements

Ximena Lincolao, Chilean Minister of Science Technology, Knowledge, and Innovation, visits ESO Headquarters

Fri, 10 Jul 2026 16:45:00 +0200

Today, 10 July 2026, the Chilean Minister of Science, Technology, Knowledge, and Innovation, Ximena Lincolao, visited ESO’s Headquarters in Garching bei München, Germany together with a small delegation. The visit, the second by a Chilean Science Minister in just two years, marks the first time the new Minister, who took office just a few months ago, visits ESO’s premises. It underscores the close collaboration between ESO and Chile, which remains vibrant and strong since the organisation and the country first signed a partnership agreement more than 60 years ago.

The visitors were welcomed by ESO Director General Xavier Barcons, ESO Director for Science Jarle Brinchmann, ESO Director of Engineering Sara Krauss, ESO Director of Programmes Adrian Russell and ESO’s Institutional Affairs Officer Beatrice Kioko. During the visit, Minister Lincolao had the opportunity to learn more about ESO’s development activities in Germany and operations in Chile, as well as its contributions to the development of Chilean astronomy, societal engagement and opportunities for local industry.

As part of the visit, they toured ESO’s Headquarters, including ESO’s Large Integration Hall, where components of ESO's Extremely Large Telescope are assembled, and other engineering facilities. Minister Lincolao also met with several ESO staff members, including Chilean staff working at the ESO Headquarters, before visiting the ESO Supernova Planetarium & Visitor Centre.

ESO Director General Xavier Barcons said: "Chile has the world’s most pristine dark skies for astronomy, which we are privileged to observe with our telescopes in the country, while contributing to the growth of Chilean astronomy and fostering technological innovation. We are very honoured to welcome Science Minister Lincolao to our headquarters in Germany to further strengthen our collaboration, for mutual benefit.”

ESO Annual Report 2025 now available

Wed, 08 Jul 2026 16:00:00 +0200

The ESO Annual Report 2025 is now available online, offering an engaging and high-level overview of ESO’s activities from the past year. The report was recently approved by the ESO Council at its June 2026 meeting.

Among the highlights are:

The latest progress in the construction of ESO’s Extremely Large Telescope (ELT), including the topping out ceremony for the ELT dome.
A major milestone for the Very Large Telescope (VLT) Interferometer and the GRAVITY+ project, as the VLT’s Unit Telescopes 1, 2 and 3 are equipped with laser guide star units.
The groundbreaking ceremony for CTAO-South, the southern array of the Cherenkov Telescope Array Observatory, now under construction at ESO’s Paranal site.
A selection of the fascinating scientific results published during 2025 using observations from ESO facilities.
ESO’s ongoing mission to protect dark and quiet skies, as well as how ESO contributes to and engages with society and our communities.
News from the La Silla Paranal Observatory and the Atacama Large Millimeter/submillimeter Array (ALMA), including forthcoming instruments and upgrades.
Technology development and R&D that keeps ESO facilities at the forefront of astronomy.

A “What is ESO?” introduction and “ESO’s year in numbers” at the start give an introduction to the organisation at a glance, and the report is illustrated throughout with beautiful astronomical images and photographs of the activities, observatory sites, and people.

This report is available to download for free and printed copies will be available in the ESOshop, free of charge with the exception of shipping costs, in the coming weeks.

ESO signs contract for next-generation deformable mirror for the VLT

Mon, 22 Jun 2026 16:00:00 +0200

Today, at ESO’s Headquarters in Garching, Germany, ESO and the AdOptica consortium signed a contract for the design and production of a new adaptive mirror, to be installed at our Very Large Telescope (VLT). AdOptica, a consortium made up of two Italian companies, Microgate and A.D.S. International, is a long-standing ESO industrial partner, working on projects such as the adaptive M4 mirror for ESO’s Extremely Large Telescope. ESO’s Director General Xavier Barcons, together with Roberto Biasi of Microgate and Daniele Gallieni of A.D.S. International were present for the signing.

ESO's VLT has four 8-metre Unit Telescopes but at present only one of them, UT4, has an adaptive optics facility, which includes a deformable mirror (the secondary, second in the path of light), as well as four lasers. Using either natural guide stars or artificial guide stars created by these lasers as references, we can measure how much the light from cosmic objects is deformed by Earth’s atmosphere. The adaptive or deformable mirror, which can change its shape very fast and with nanometric precision, then cancels out the deformation of the light in real time, giving us a much sharper view of the cosmos than would otherwise be possible. Because of its adaptive optics systems, together with highly demanded instruments, UT4 is one of the most oversubscribed telescopes on Earth.

Since November 2025, Unit Telescopes 1, 2 and 3 have each been equipped with a laser, as part of the GRAVITY+ upgrade. While these lasers are currently only used for observations with the VLT Interferometer, when all Unit Telescopes are observing together, they can also be used for stand-alone observations (with suitable instruments) — if the telescope they are projected from is equipped with a deformable mirror.

By procuring the production of a new deformable secondary mirror, which is planned for installation on UT3, ESO will expand the adaptive optics capabilities of the VLT with the help of AdOptica, who also built the deformable secondary mirror on UT4. This will reduce the pressure on UT4, since instruments equipped with a wavefront sensor can now also be installed on UT3 and benefit from state-of-the-art adaptive optics corrections. Ultimately, the improvements will allow more observations of cosmic objects in finer detail than is possible today.

The ESO-Government of Chile Joint Committee has opened the national application period for 2026

Wed, 03 Jun 2026 16:00:00 +0200

The ESO-Government of Chile Joint Committee has opened the application process for its national financing fund for 2026. In this new round, more than 500 million Chilean pesos will be distributed among the selected initiatives.

To continue driving and supporting scientific and technological development in Chile through astronomy, ESO and the Government of Chile have been funding projects since 1995 that promote astronomical research, the development of advanced human capital, technological innovation, education, and science outreach within the country.

Thus, academic projects such as the "Laboratorio de Polvo Cósmico de la Universidad Diego Portales” cultural projects such as "Reconocimiento y puesto Valor del Patrimonio Astronómico” and artistic projects such as "Pintura Cósmica” were financed by this fund in 2025.

The ESO-Government of Chile Joint Committee, responsible for establishing the fund’s guidelines and evaluating proposals, is composed of representatives from the European Southern Observatory and the Chilean Government. Chile is represented by the Division of Science, Energy, Education, Innovation, and Astronomy (DECYTI) of the Ministry of Foreign Affairs, with the participation of the Ministry of Science, Technology, Knowledge, and Innovation and the Chilean Astronomical Society (SOCHIAS).

Proposals must be submitted no later than July 20, 2026, at 11:59 p.m. Chilean time, in English or Spanish, using the following online form. Applications must follow the rules indicated in the link at the bottom of the page.

For further information and inquiries, please contact María Adriana Arrau at the ESO Representative Office in Chile.

ESO and DZA sign collaboration agreement

Wed, 03 Jun 2026 14:00:00 +0200

ESO has signed an agreement with the German Centre for Astrophysics (DZA), a major research infrastructure for astrophysics and related technology development being established in the city of Görlitz in eastern Germany, right on the border with Poland. This new collaboration will identify shared research priorities and develop dedicated R&D projects, in areas including optical and near-infrared detector and radio receiver technologies, and novel instrumentation and telescopes. The partnership will also establish training opportunities for young researchers and engineers, as well as exchange programmes for students and staff.

This agreement is part of ESO's Technology Development Programme (TecDev), through which ESO collaborates with leading research organisations to advance key technologies that make the organisation’s mission possible. The goal is to keep ESO's facilities at the forefront of astronomy by taking early-stage technologies and developing them into mature solutions for future projects. Currently, TecDev focuses on five main areas: adaptive optics technologies; science detectors; calibration sources for spectroscopy; technologies in mm and sub-mm astronomy; and validation of technologies using ESO’s infrastructure.

As an immediate goal for the near future, collaboration on optical and near-infrared image sensors is an attractive area of joint research and development. The vibrant ecosystem of semiconductor industries and academia in and around Dresden, in the immediate vicinity of Görlitz, provides excellent opportunities for development in this area.

The DZA is an emerging major research hub in Germany, whose mission includes providing access to international astronomical facilities. The joint effort between ESO TecDev and the Centre for Technology Development at DZA to develop and promote new technologies for telescope instrumentation will be beneficial to both ESO and the DZA, as well as to the scientific community at large.

President of the Czech Republic and Chilean Minister of Foreign Affairs visit ESO’s Paranal Observatory in Chile

Mon, 20 Apr 2026 16:00:00 +0200

Petr Pavel, President of the Czech Republic, his wife Eva Pavlová, Francisco Pérez Mackenna, Chilean Minister of Foreign Affairs, and a large Czech delegation have concluded a visit to ESO’s Paranal Observatory in Northern Chile. The delegation included the Czech Ambassador to Chile, Pavel Bechny, the President of the Czech Academy of Sciences, Radomír Pánek, the President of the Astronomical Institute of the Czech Academy of Sciences, Michal Bursa, as well as journalists and representatives of Czech companies.

ESO’s Director General Xavier Barcons welcomed President Pavel, Minister Pérez Mackenna and the rest of the delegation to the Paranal Observatory on 17 April. The visitors toured ESO's Extremely Large Telescope (ELT) construction site, before heading to the Very Large Telescope (VLT), where they observed the opening of one of the telescopes. Later in the evening, they watched the lasers from the VLT platform — a key element of the telescope’s adaptive optics system that compensates for turbulence in the Earth’s atmosphere — and visited the VLT control room. During their stay, the high-level visitors had the opportunity to experience Paranal's facilities and outstanding dark skies in person, as well as find out more about the ELT and how it will expand our understanding of the Universe. The delegation also learned about the business opportunities created by ESO's development of cutting-edge technology..

The Czech Republic, joined ESO in 2007, becoming the first Member State from the Central and Eastern European region. Czech institutions have made important contributions to the development of instruments and telescopes owned by ESO and those hosted at ESO sites. For instance, Czech companies have contributed to both Paranal and ELT instrumentation. Further south, at ESO’s La Silla Observatory, a consortium led by the Czech Academy of Sciences has also given new life to ESO’s 1.52m telescope, with the PLATO Spec instrument.

"We are very pleased to welcome President Pavel and his delegation to Paranal,” said Barcons. “The Czech Republic has been a very engaged and supportive ESO Member State for almost 20 years. The introduction of an engineering and scientific trainee programme at ESO for Czech nationals, now a model for other Member States, and the engagement of Czech institutes in ELT instrumentation, are examples of how the collaboration between ESO and the Czech Republic is both advancing astronomy and investing in the next generation of scientists and engineers."

Regarding the presence of Minister Pérez Mackenna during the visit, Barcons said: "The Chilean Minister of Foreign Affairs' participation on this visit underscores the solid and fruitful relationship that ESO has maintained with Chile — which hosts all of our existing telescopes — for more than six decades. Technology developed by the Czech Republic and other ESO Member States bears scientific fruits in large part thanks to this long-standing collaboration with Chile, whose remarkably dark and pristine skies we are privileged to observe from ensure the highest scientific value of the observations."

Puerto de Ideas Antofagasta 2026: second night tour at Paranal Observatory will take place on 25 April

Fri, 10 Apr 2026 17:00:00 +0200

Following a successful first edition, the European Southern Observatory (ESO) will hold its second public night tour of ESO’s Paranal Observatory in northern Chile. The tour is taking place in the context of ESO’s participation in the Puerto de Ideas Antofagasta 2026 Science Festival, happening in the nearby city of Antofagasta. This tour will take place on Saturday 25April.: Registration is free, and spots are limited and assigned on a first-come, first-served basis.

Key Information:

Where: Paranal Observatory

When: Saturday, 25 April.

Time: Bus departs from Antofagasta at 14:30 and leaves Paranal Observatory at 19:50, when the tour ends.

Registration: Free and open to the public on a first-come, first-served basis.
- Registration opens on April 16 via the Puerto de Ideas website.

Capacity: 40. Limited spots available, on a first-come, first-served basis.

What does the visit include?
- Round-trip bus transportation from a pickup point in the city of Antofagasta, which will be communicated to confirmed visitors.
- The tour at the observatory will last three hours, during which visitors will be able to see the opening of ESO’s Very Large Telescope (VLT), watch the sunset from the Cerro Paranal platform, and visit the control room where the telescopes are operated. Additionally, depending on operational conditions, the tour will include access to one of the VLT Unit Telescopes (UT) and the Paranal Residencia.
- At the end of the tour, there will be a guided naked-eye sky observation during which visitors can appreciate the beauty of the world’s clearest skies and become familiar with some of the celestial objects visible at this time of the year.

Can I get there on my own?
- No. ESO provides round-trip transportation from the pickup point in the city of Antofagasta only for confirmed visitors. It is not permitted to arrive at the observatory by your own means.

When is the next night tour?
- Unlike regular Saturday tours, these night tours are held only on select dates throughout the year, generally in conjunction with special regional or national events. Each new date will be announced on this website and on ESO Chile’s Instagram: @eso.chile .

ESO launches first programme of night tours of scientific observatories in Chile

Fri, 13 Mar 2026 18:00:00 +0100

In March 2026, on the occasion of Chile’s Astronomy Day celebrations, ESO will mark a milestone by launching its first programme of public night tours at its La Silla and Paranal observatories. These visits will give people from Chile and around the world the opportunity to see some of the Organisation's most iconic telescopes, as well as enjoy the planet's most pristine dark skies. TICKETS ARE SOLD OUT FOR THE MARCH 21ST TOUR.

The programme will offer at least eight visits per year, during which the public will see the opening of telescopes at sunset in La Silla or Paranal and observe the stars, with the naked eye, under one of the darkest skies in the world. The programme will also include guided tours of different areas of the observatories, round-trip transportation from different cities in the Antofagasta and Coquimbo regions, as well as some surprises.

The first visit will take place at the Paranal Observatory on March 21 as part of the celebrations for Astronomy Day in Chile. It will also have the collaboration of the Antofagasta Region office of Chile’s National Tourism Service (SERNATUR). The rest of the night tours at Paranal and La Silla will be scheduled annually to coincide with emblematic dates, including the Puerto de Ideas Antofagasta festival, Chile’s National Heritage Day, Chilean Science Week, among others.

For this inaugural tour, registration will be through SERNATUR Antofagasta's social media channels and will be open to anyone in the region, including domestic and international tourists. For future visits, registration details will be provided through ESO's official channels.

These new night tours will last three hours at the observatories, where visitors will be able to watch the sunset from the observatories and visit the control rooms from where the telescopes operate. In addition, depending on operational conditions, the visits will allow visitors to see areas of ESO’s telescopes such as the Very Large Telescope (VLT) at Paranal or the New Technology Telescope (NTT) at La Silla.

Each visit will also include a guided observation of the sky with the naked eye, during which visitors will be able to appreciate the beauty of the world's most pristine skies and familiarise themselves with some of the celestial objects visible at different times of the year.

For decades, ESO has offered a regular programme of public visits that attracts more than 7,000 people a year and that, until now, only included daytime tours. Regarding this, Laura Ventura, ESO's Deputy Representative in Chile, said: “We are proud to be able to enrich the programme of visits to our observatories, so that more people, particularly from the respective regions and communities, can learn about this scientific, technological, and natural heritage that is unique in the world. It is a dream of many years that is now coming true.”

Italian Minister of University and Research visits ELT site

Fri, 13 Mar 2026 14:00:00 +0100

Anna Maria Bernini, the Italian Minister of University and Research, and a small delegation have completed a visit to ESO’s Extremely Large Telescope (ELT) in Chile’s Atacama Desert. The group included Valeria Biagiotti, Italy’s Ambassador to Chile, and Roberto Ragazzoni, President of the Italian National Institute for Astrophysics (INAF) and ESO Council Member. During the visit, the Minister and her delegation learnt about ESO’s groundbreaking facilities and saw first-hand the progress at Cerro Armazones, where the ELT is being constructed.

On 12 March, ESO’s Director General Xavier Barcons and ELT Programme Manager Roberto Tamai welcomed Minister Bernini — who travelled to Chile for the inauguration of the country’s new President — and briefed the visitors on ESO’s mission and operations. The delegation then toured the ELT site, learning about the 'world’s biggest eye on the sky' and Italy's substantial contributions to the project. Later, they visited the future southern-hemisphere site of the Cherenkov Telescope Array Observatory, located just a few kilometres from the ELT.

Italy, an ESO Member State since 1982, has played a pivotal role in many of the organisation's technological and scientific achievements. For example, several current and future instruments operating on ESO telescopes were built by consortia led by INAF institutes. Italy also maintains a leading role in the ELT: a consortium of Italian companies is currently constructing the dome and telescope structure, representing the largest ground-based astronomy contract ever awarded. The direct economic return to Italian companies and institutions participating in ESO projects exceeded 360 million EUR over the 2008-2025 period.

More than 1100 studies with ESO data published in 2025

Tue, 10 Mar 2026 14:00:00 +0100

Around 1150 studies using data collected at ESO's observatories were published last year — the second year in a row that publications have exceeded 1100. It also marks the ninth consecutive year where observations at ESO's facilities have led to more than 1000 published studies annually. The ESO Library, Documentation, and Information Services Department have updated their publication statistics to include 2025 with a detailed breakdown of the contributions from each ESO facility [1].

As in previous years, data from ESO's Very Large Telescope (VLT) and the VLT interferometer (VLTI) have dominated in publications, contributing to around 670 studies in 2025. The facilities' broad range of instruments, plus the location at Paranal Observatory in Chile's Atacama Desert — a site with unique observing conditions including pristine dark skies — make them a flagship in ground-based astronomy. The Multi Unit Spectroscopic Explorer (MUSE) continues its six-year streak as the most productive VLT/I instrument, with data in over 200 papers. A highlight from MUSE last year was the publication of an ultra-detailed thousand-colour image of the Sculptor Galaxy. Another highlight from the VLT published last year used data from the Ultraviolet and Visual Echelle Spectrograph (UVES), the second most productive VLT instrument with over 120 papers in 2025, to find a planet in a perpendicular orbit to a pair of stars.

The survey facilities, ESO’s Visible and Infrared Survey Telescope for Astronomy (VISTA) and the VLT Survey Telescope (VST) [2], also found at Paranal Observatory, produced data for over 100 papers. Data from ESO's first observatory, La Silla, contributed to about 200 studies last year, an increase from 177 in 2024. This shows how the observatory remains at the forefront of research, especially thanks to instruments such as HARPS, High Accuracy Radial velocity Planet Searcher, on ESO's 3.6-metre telescope.

The Atacama Large Millimeter/Submillimeter Array (ALMA), co-owned by ESO, provided data for over 550 publications in 2025. Around half of these papers relied on observing time granted to astronomers based in Europe. Highlights of ALMA studies published last year include the discovery of oxygen in the most distant known galaxy and observations of the creation of a new solar system. Located next to ALMA, observations from the Atacama Pathfinder Experiment (APEX), which was operated and hosted by ESO until the end of 2025, led to around 45 papers last year. Of these, close to 20 used data obtained during ESO observing time.

A record number of publications employed data from the ESO Science Archive Facility, with around 530 papers relying partly or exclusively on archival data. This also made 2025 the year with the highest percentage of ESO publications using the archive, at 46%, underscoring the value of legacy observations in cutting-edge astronomical research. Furthermore, over a quarter of all 2025 publications relied on archival data alone, without any ESO observations obtained by the authors themselves.

The impressive publication numbers emphasise the significant role ESO plays in helping astronomers advance our understanding of the Universe. This is made possible thanks to the work of the wider astronomical community and ESO staff, the advanced technology of ESO’s facilities, and the continued support of ESO’s member states and of Chile.

Notes

[1] Papers can use data from more than one facility, therefore the total number cannot be calculated by adding all publications of the individual sites.

[2] The VST project was a joint venture between ESO and the Capodimonte Astronomical Observatory, part of the Italian National Institute for Astrophysics (INAF). As of 1 October 2022, this is a sole project of INAF, hosted by ESO at Paranal. Only papers based (entirely or partly) on ESO VST time are included in the statistics.

More Information

The statistics presented here are derived from the ESO Telescope Bibliography (telbib), a database of refereed papers published by the ESO users community. Telbib is developed and curated by the ESO Library, Documentation, and Information Services Department. While text-mining scripts are applied when screening the literature for ESO data papers, articles are carefully examined by the curators before they are added to the database to ensure that all telbib papers use partly or exclusively data from ESO facilities for which observing time was recommended by ESO. The public telbib interface provides visualisations of search results including on-the-fly graphs and predefined charts.