Announcements

12 November 2021: As one of the world’s leading astronomy organisations, the European Southern Observatory (ESO) is fully committed to fighting climate change by reducing the environmental impact of its activities. The ESO Directors Team has now approved a new set of measures to gradually decrease the organisation’s carbon footprint over the coming years. The measures are inspired by the United Nations guidelines and build upon the actions ESO had already adopted in the past. ESO carries out the design, construction and operation of powerful ground-based observing facilities, providing astronomers worldwide with some of the best tools for their research and discoveries. This work leads to invaluable scientific and technological progress and other societal benefits, but also unavoidably places demands on resources, energy and the environment. In a carbon audit conducted in 2019, ESO’s 2018 footprint budget was estimated to be around 28 000 tonnes of CO2 equivalent per year (tCO2e/yr) [1], with ...

6 October 2021: The largest adaptive mirror ever built, the M4 mirror for ESO’s upcoming Extremely Large Telescope (ELT), has reached an important milestone in its development: all six petal-shaped segments that make up the mirror are now completed. M4, the fourth mirror in the light path of the telescope, can change shape quickly and very precisely, and is a key part of the ELT’s adaptive optics system. Light from cosmic objects is distorted by our planet’s atmosphere, producing blurred images. To correct for these distortions, the ELT will use advanced adaptive-optics hardware and software, some of which has been specially developed for the telescope. This includes powerful lasers that create artificial reference stars when there aren’t stars bright enough close to the object of interest to allow measurements of atmospheric distortions, and fast and accurate sensing cameras that measure these distortions. The measurements are then passed to extremely fast real-time computers that ...

11 June 2021: Preparations are being put in place to resume construction work on ESO’s Extremely Large Telescope (ELT) at Cerro Armazones in Chile, following disruption due to the COVID-19 pandemic, which forced the closure of the site in mid-2020. As work on manufacturing and design elements of the ELT in Europe progressed steadily, the evolution of this complex and ambitious project, set to revolutionise modern astronomy, has been closely monitored over the past year. ESO’s ELT is now expected to deliver the first scientific observations in September 2027, about half a year after an initial “telescope technical first light”. In the last few weeks, the Italian consortium ACe (Cimolai, Astaldi) in charge of the dome and main structure construction, has started preparations to resume on-site activities on ESO’s ELT in the Chilean Atacama Desert, within the health and safety restrictions established by the country’s authorities. With this important return to work in ...

2 March 2021: The latest edition of ESO's journal, The Messenger, is now available online. This is a special issue dedicated to the instrumentation programme for ESO’s Extremely Large Telescope (ELT). Selecting instruments for any telescope is a crucial step, making sure that the astronomical community it serves can undertake the scientific projects for which the telescope was designed. ESO has been working with its community of astronomers and instrument builders to establish the sequence in which the instruments planned for the ELT will be built and delivered to the observatory. This edition of The Messenger provides a status overview of the ELT instrumentation programme. Highlights from this special issue: Instrumentation for ESO’s Extremely Large Telescope SUPER — AGN Feedback at Cosmic Noon Mapping the Youngest and Most Massive Stars in the Tarantula Nebula with MUSE-NFM Download The Messenger in PDF format or visit The Messenger website to subscribe and receive a free ...

22 January 2021: The European Southern Observatory (ESO) is a testament to research, innovation, and collaboration in Europe with a far reaching and invaluable impact on society. The new publication “ESO’s Benefits to Society” explores ESO’s contributions to its Member States across five areas: science and engineering, economy and innovation, talent development, education and outreach, and international collaboration and policy. In science and engineering, ESO and its telescopes have been instrumental in several ground-breaking discoveries. In 2020, for example, a Physics Nobel Prize was awarded for research on the Milky Way’s black hole done with ESO telescopes. ESO enables discoveries such as this by constructing and operating world-leading observatories, which push the boundaries of engineering. ESO innovations extend beyond the organisation’s remit; for example, techniques from MUSE, an instrument on ESO’s Very Large Telescope, are being transferred for use in medicine and cancer diagnostics. ESO additionally provides economic benefits to society. In 2019, ...

14 January 2021: ESO has launched a new website to deliver a wealth of information about its Extremely Large Telescope (ELT), a forthcoming observatory that will study the Universe from Chile’s Atacama Desert. Created for a wide range of audiences, the general public and astronomy experts alike can dive into the website to discover the new telescope, its instruments, and how it will further our knowledge of the cosmos. The website showcases some of the most important scientific questions that astronomers hope the ELT will answer, complemented by striking visuals of the telescope, its surrounding structure and its various instruments and mirrors. It also features interesting facts about the ELT, which will be the largest visible and infrared light telescope in the world with a 39-metre main mirror, some of the history behind this ambitious and challenging telescope, as well as a timeline with some of the project’s most important milestones. This is ...

4 December 2020: The Extremely Large Telescope (ELT), ESO’s new flagship telescope being built to answer the biggest questions about our Universe, has received a 10% increase to its budget. The funding boost approved by the ESO Council — the organisation’s main governing body — brings the total cost of the project to €1.3 billion. The 39-metre telescope, being erected in Cerro Armazones near ESO’s Paranal Observatory in northern Chile, will start operating later this decade. “Council’s decision means ESO has the funds to build an ambitious and extremely powerful science machine, fully integrated with ESO’s Paranal Observatory, that meets the longer-term aspirations of the astronomy community,” says ESO Director General Xavier Barcons. Overall, 80% of the ELT’s budget is being invested in contracts with industry in ESO member states and in Chile. The funding boost will strengthen the scientific capabilities of the under-construction telescope, bringing them in line with those envisioned in ...

24 November 2020: M1, the main mirror of ESO’s Extremely Large Telescope (ELT), is moving closer to completion with the approval of the final design for its edge sensors, with its positions actuators also nearing this key milestone. The sensors and actuators are crucial to the optical quality and functionality of the giant 39-metre mirror. The ELT is planned to start operating later this decade in the Chilean Atacama Desert. The primary mirror on the ELT, M1, is composed of 798 hexagonal segments, made of a thin glass-ceramic material. To ensure the optical quality of the mirror, its segments have to work together to maintain the mirror’s shape, despite changes in the telescope's position and in external conditions, such as temperature, pressure and wind. Movable supports and sensors for the mirror, namely the M1 position actuators and edge sensors, allow each mirror segment to move independently and with nanometric (1 millionth of a ...

19 November 2020: While the construction of ESO's Extremely Large Telescope (ELT) in Chile's Atacama Desert is on hold due to the COVID-19 pandemic, important progress on the project is being made elsewhere. In the past few months, design activities for the telescope’s dome have been completed (in a process called final design review) and manufacturing of the dome components is currently ongoing. The extensive design review solved several complex problems inherent to building a top-performing science machine, with strict scientific requirements, in the extreme environment of the Atacama Desert. Engineers also had to ensure the operational requirements were met: high reliability, low maintenance, and resistance to earthquake and strong winds, for example. The latest renderings show what the dome will look like, and how subtle but important changes were made from the older designs. The ELT dome and telescope structure contract was placed with the Italian consortium ACe (Cimolai, Astaldi). It covers ...

6 November 2020: A major component of ESO’s Extremely Large Telescope (ELT), its first prefocal station or PFS-A, is now close to completing its final design review. With this milestone nearly reached, ESO has signed a contract with Spanish company IDOM for a second prefocal station, PFS-B. The two ELT prefocal stations, which are designed and manufactured by IDOM, are large structures measuring over 9 metres tall and each standing on supporting platforms, located on opposite sides of the telescope main structure. Working at the interface between the telescope’s five-mirror system and its instruments, they have a triple function: control the telescope mirror alignment (including the precise pointing on-sky of the telescope structure), ensure the segmented main mirror continues to act as one, and distribute light to the telescope instruments. Sensing starlight to check alignment The ELT is extremely sensitive to very small changes in environmental conditions, which will shift the mirrors out ...

14 October 2020: How do astronomers explore the Universe beyond the human senses? A new show from Evans & Sutherland, made in association with ESO and the Houston Museum of Natural Science offers an insight into the greatest revolution in astronomy since the invention of the telescope. Unseen Universe invites you to step into the wondrous new age of exploration and understanding. For millions of years, our view of the heavens was limited by our eyes, allowing us to see only a narrow band of electromagnetic radiation we call visible light. Now, we have the technology that allows us to look at the sky with superhuman sight and accuracy. The planetarium show Unseen Universe presents an exciting look at cutting-edge astronomy. Learn more about the supercomputers that link clusters of telescopes, continents apart. Follow the fleet of spaceborne observatories that extend our senses across space and time. Find out how the new detectors ...

23 September 2020: The 2021 edition of one of our most popular products, the ESO Calendar, is now available and can be purchased from the online ESOshop and in the ESO Supernova Planetarium & Visitor Centre. The calendar’s cover features a spectacular starscape around the relatively unknown central object, Gum 15, a nebula in which stars are being born. The image also features one of the closest supernova remnants to Earth, which exploded between 11 000 and 12 300 years ago and is located 800 light-years away from our cosmic home. For the month of March, the bright band of the Milky Way arcs above the ALMA antennas on the Chajnantor plateau. One of the closest stellar nurseries to Earth, the Orion Nebula, is the chosen image for July and the massive 3-tonne blank for the Extremely Large Telescope’s (ELT) secondary mirror is the star of September. Finally, in December the viewer will ...

11 September 2020: The Royal Observatory Greenwich has announced the results of its hugely popular, global photographic competition, a yearly contest to find the most beautiful and spectacular visions of the cosmos. The winners of Insight Astronomy Photographer of the Year 2020 will be showcased in the Insight Investment Astronomy Photographer of the Year exhibition at the National Maritime Museum, opening to the public on 23 October 2020. ESO joined the competition in 2016 by contributing a judge and further spreading the word about the competition among its community. French photographer Nicolas Lefaudeux has outcompeted thousands of amateur and professional photographers from around the globe to win the Royal Observatory Greenwich’s title of Insight Investment Astronomy Photographer of the Year 2020. Winning images in the other categories and special prizes include the breath-taking Aurora Borealis above Hamn i Senja, Skaland, in Norway by Nicholas Roemmelt (Germany); the image taken by Łukasz Sujka (Poland) ...

25 August 2020: An international team of experts, including ESO staff, has produced a new report that explores practical ways to address the impact of large satellite constellations on astronomy. The report concludes that large constellations of bright satellites in low Earth orbit will fundamentally change ground-based optical and infrared astronomy and could impact the appearance of the night sky for stargazers worldwide. It also offers a roadmap for observatories and satellite operators to work together to lessen these impacts. The report offers two main findings. First, low-Earth-orbiting satellites disproportionately affect science programmes that require twilight observations, such as searches for Earth-threatening asteroids or for the visible-light counterparts of fleeting gravitational-wave sources. Satellites orbiting below 600 kilometres have limited interference with astronomical observations during the night’s darkest hours. But satellites at higher altitudes, such as the 1,200-km-high constellation planned by OneWeb, can be illuminated all night long during summer and for much of ...

18 June 2020: The ESO Annual Report 2019 is now available. It presents a summary of ESO’s many activities throughout the year. The contents include: Research highlights from ESO facilities, including the first image of the shadow of a supermassive black hole, groundbreaking investigations of exoplanets and how the shapes and characteristics of asteroids are being uncovered in unprecedented detail from the ground. A summary of activities at ESO’s front-line observatories in Chile: 2019 was a very special year for the La Silla Observatory, marking 50 years since its inauguration. The celebrations of this anniversary were further distinguished by the opportunity to witness a rare total solar eclipse at the observatory. The latest news from the Atacama Large Millimeter/submillimeter Array (ALMA) and ESO's Extremely Large Telescope (ELT). News about ESO staff and infrastructure, and recommendations from the ESO Visiting Committee. This product is available to download for free and will soon be available ...

5 June 2020: METIS, the powerful imager and spectrograph for ESO’s Extremely Large Telescope (ELT), has passed its Preliminary Design Review at ESO’s headquarters in Garching, Germany. METIS, short for Mid-infrared ELT Imager and Spectrograph, will make full use of the giant main mirror of the telescope to study a wide range of science topics, from objects in our Solar System to distant active galaxies. METIS will be extremely well suited to study the life cycle of stars, from infant stars and planet-forming discs to older stars near the end of their lifetime. The ELT will be the largest optical to mid-infrared telescope on Earth when it starts operations towards the middle of this decade. With its 39-metre primary mirror and advanced adaptive-optics systems, it will have six times the resolution of the James Webb Space Telescope. METIS will take full advantage of this remarkable telescope and its adaptive optics to probe the ...

11 May 2020: The latest edition of ESO's quarterly journal, The Messenger, is now available online. Find out the latest news from ESO on topics ranging from new instruments to the latest science discoveries. Highlights of this edition include: 2018 Visiting Committee Report: H.-W. Rix SPHERE Unveils the True Face of the Largest Main Belt Asteroids: P. Vernazza et al. The ASPECS Survey: M. Aravena et al. Download The Messenger in PDF format or visit The Messenger website to subscribe and receive a free printed copy. This product is also available in the ESOshop. Confirm your ESO Messenger subscription to the print edition by 10 September. Please hold on to your envelope when it arrives — further details are on the back page of The Messenger.

9 March 2020: Final update (23 May 2022): From 28 May, ESO will reopen public visits to its observatory sites in Chile, following two years of pandemic-related closures. For more information, please check our dedicated announcement. Update (9 May 2022): At its headquarters in Garching, ESO started a new phase of its ramp-up plan this week, with staff now generally working full-time on site. Some COVID-19 health and safety measures remain. Visitors can now come to HQ, subject to receiving an invitation and completing a health declaration form, including acknowledgement of the applicable COVID-19 safety rules. The ESO Supernova Planetarium and Visitor Centre is operating with its normal opening hours and is offering planetarium shows and tours in the exhibition, subject to COVID-19 health and safety measures. Update (30 March 2022): Two years after operations at ESO’s observatories in Chile were scaled back due to the pandemic, the organisation has now moved the ...

19 February 2020: M1, the primary mirror of ESO's Extremely Large Telescope (ELT), is the centrepiece of the revolutionary astronomy machine currently under construction in Chile's Atacama Desert. Too large to be made from a single piece of glass, the 39-metre-diameter mirror will consist of 798 hexagonal segments, each about 5 centimetres thick and measuring 1.4 metres across. Producing 798 segments (plus a few additional pieces) that can work together as a single giant mirror to deliver unprecedented astronomical data is an engineering challenge with milestones worth celebrating. M1 segments begin their life at SCHOTT in Germany as blanks made of Zerodur©, a glass-ceramic material that has very low thermal expansion. After the casting and machining of the blanks to their approximate shape at SCHOTT, the segments are delivered to Safran Reosc, in France. The first 24 segments are currently at Safran Reosc ready to be polished. Polishing facility inaugurated in Poitiers To ...

4 February 2020: The Big Science Business Forum 2020 (BSBF2020) is the second such event, intended as a one-stop-shop where European businesses and other stakeholders can learn about future investments and procurements on the part of Europe’s Big Science organisations. The event is organised by an International Organising Committee consisting of 10 Big Science organisations, ESO being one of them. The event will be hosted by the Centre for the Development of Industrial Technology (CDTI), Ministry of Science, Innovation and Universities and CIEMAT - Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas. It takes place from 6 to 9 October 2020 in Granada, Spain. Update 8 October 2020: Given the current situation, the BSBF2020 International Organising Committee (IOC) has decided to postpone the BSBF2020 event to 28 September - 1 October 2021. In the meantime, several webinars are being organised. Big Science is a term that encapsulates the way in which scientific progress increasingly ...