Announcements

14 March 2024: The construction of ESO’s Extremely Large Telescope (ELT) in the Chilean Atacama Desert has reached a new milestone: a team at ESO’s Paranal Observatory have added a reflective, shiny layer, as well as special sensors, to the first segments of the telescope’s primary mirror. This “coating” means the segments are now essentially ready to start observing the skies, once installed at the heart of the world’s largest optical telescope later this decade. The 39-metre primary mirror of ESO’s ELT, known as M1, will be by far the largest mirror ever made for a telescope. Too large to be made from a single piece of glass, it will consist of 798 glass-ceramic hexagonal segments, each about five centimetres thick and 1.5 metres across. The mirror segments are manufactured in Europe in a multi-step, multinational process. The first 18 made their way across the ocean to Paranal earlier this year, and coating ...

28 February 2024: For the seventh year in a row, observations conducted at ESO’s observatories have led to more than 1000 scientific publications in a year. Recently, the ESO Library, Documentation, and Information Services Department has updated their detailed statistics on publications using ESO data, presenting each facility's contributions in 2023 [1]. The most significant contributions to these publications come from ESO’s Very Large Telescope (VLT) and the VLT Interferometer (VLTI) at Paranal Observatory, which yielded data included in over 600 studies. Highlights include the detection of distant gas clouds with leftovers from the first stars in the Universe and the most distant fast radio burst to date. For the last four years, the Multi Unit Spectroscopic Explorer (MUSE) has been the most productive VLT instrument, producing data for over 200 papers in 2023 alone. Also located at Paranal Observatory, the Visible and Infrared Telescope for Astronomy (VISTA) and the VLT Survey Telescope ...

15 February 2024: Delegations representing 102 countries agreed last week to discuss the impact of large satellite constellations on astronomy at a meeting of the United Nations Committee on the Peaceful Uses of Outer Space (UN COPUOS). After intense discussions, COPUOS’ Scientific and Technical Subcommittee has agreed to add an agenda item for the next five years with the title: "Dark and Quiet Skies, astronomy and large constellations: addressing emerging issues and challenges". As the UN’s top body for space-related matters, the committee deals with all topics related to international cooperation and the exploration of space and planetary bodies, including the deployment of satellites, space debris mitigation, long-term sustainability of space and the use of orbital slots. The proposal championed by ESO’s partner and host state Chile and ESO’s member state Spain — both countries hosting significant international astronomy infrastructure — was informed by the astronomy community and received widespread support from many ...

29 January 2024: Astronomers have, for the first time, made a direct measurement of the mass of a distant black hole, one so far away that light from its surroundings took 11 billion years to reach us. The team, led by Taro Shimizu at the Max Planck Institute for Extraterrestrial Physics in Germany, found the black hole, called J0920, to have a mass of about 320 million times that of the Sun. This achievement, described in a paper published today in Nature, has been made possible thanks to GRAVITY+, a series of ongoing upgrades to ESO’s Very Large Telescope Interferometer (VLTI) and its GRAVITY instrument. To directly measure the mass of a black hole, astronomers use telescopes to track the movement of gas and stars around it. The faster these move, the more mass is encased within the material’s orbit. This technique has been used to measure the mass of nearby black holes, ...

16 January 2024: After a 10 000 km journey across the world, the first mirror segments of ESO’s Extremely Large Telescope (ELT) have safely arrived in their next home, the ELT Technical Facility at ESO’s Paranal Observatory in the Chilean Atacama Desert. A total of 18 segments (out of 798) of the telescope’s main mirror (M1) successfully made the trip from Europe to South America, first arriving in Chile at the Antofagasta Terminal International (ATI) port last week. Once complete, the ELT’s M1 will be over 39 metres across, making it the world’s largest eye on the sky. Such scale means that the mirror can’t be cast in one piece, thus, 798 hexagonal segments will work together to form M1. An additional 133 will be produced to facilitate the segments’ recoating. Embarking on a remarkable voyage that began near Poitiers, France, where the ELT segments were finished, they then traveled by road to ...

10 January 2024: This week, the Dutch Minister of Education, Culture and Science, Robbert Dijkgraaf, visited ESO facilities in Chile at La Silla, Paranal and Chajnantor. While visiting for the official inauguration of the BlackGEM telescopes, a Dutch-Belgian project hosted by ESO at its La Silla Observatory, Minister Dijkgraaf took the opportunity of being in Chile to tour all of ESO’s observing sites. At Paranal Observatory, he was also able to visit the nearby construction site of ESO’s Extremely Large Telescope. During his visit, Minister Dijkgraaf was welcomed by ESO’s Director General Xavier Barcons. He was accompanied by a high-level delegation, including Mirjam Lieshout-Vijverberg, Vice President and representative for the Netherlands on the ESO Council, and Amina Helmi, also a representative for the country on the ESO Council. The official inauguration of BlackGEM at La Silla also included the participation of the Dutch and Belgian ambassadors to Chile and BlackGEM’s project leader Paul ...

7 December 2023: Tom Ray, Senior Professor and Director of Cosmic Physics at the Dublin Institute for Advanced Studies, Ireland, has been elected as the next president of ESO’s main governing body, the Council. He currently represents Ireland on the ESO Council and is the first Irish national to be elected ESO Council president. “I look forward to continuing my work with the ESO Council, and am honoured to be elected as the next president,” Ray says. “ESO continues to be a leader in ground-based astronomy, and the next few years will bring exciting developments. The Extremely Large Telescope, the world’s biggest eye on the sky, is over halfway completed, while the Very Large Telescope’s new instruments and infrastructure upgrades will ensure it continues to play a key role in exploring the Universe. And ALMA, which is celebrating 10 years of discoveries this year, will be able to produce much more detailed observations ...

29 November 2023: In a significant step in the direction of Open Science, ESO has formally joined the European Open Science Cloud (EOSC) Association as a Member. The Association is the legal entity governing the EOSC. The EOSC is an European Commission initiative to "enable researchers to find, create, share and reuse all forms of digital knowledge – such as publications, data and software – leading to new insights and innovations, higher research productivity and improved reproducibility in science”, in the words of former Commissioner of Innovation, Research, Culture, Education & Youth Mariya Gabriel. ESO has long supported it, by endorsing the EOSC Declaration in 2017 and with its continuing participation in ESCAPE, a project — which stemmed from the EOSC — that brings together the astronomy, astroparticle and particle physics communities in Europe in support of Open Science. By joining the EOSC Association, ESO will now be involved in its governance, as ...

28 November 2023: Today, in a celebration at Cerro Murphy in the Chilean Atacama Desert, the Nicolaus Copernicus Astronomical Center of the Polish Academy of Sciences (CAMK), along with the European Southern Observatory (ESO) and other entities, inaugurated the renewed Rolf Chini Cerro Murphy Observatory. Hosted within ESO’s Paranal Observatory, the Observatory has undergone a major rebuild since 2020 and is ready to begin scientific observations again, marking a new chapter in its history. The Rolf Chini Cerro Murphy Observatory inauguration celebrates the beginning of scientific operations for three new optical telescopes, which will join existing facilities to explore how fast the Universe is expanding. The Observatory is dedicated to the Araucaria Project, a collaboration between astronomers from Chile, the USA and Europe, focused on improving the calibration of the extragalactic distance scale, a combination of methods by which astronomers measure the distance of objects throughout the Universe. The data gathered at the ...

22 November 2023: The ESO–Government of Chile Joint Committee has announced the 20 winning projects of the 2023 call, which will distribute 563 million Chilean pesos. The ESO–Government of Chile Joint Committee funds will be invested in initiatives dedicated to developing scientific and technological research and promoting cooperation in the astronomical field. Astronomy dissemination and education projects throughout Chile will also be financed. This year, the Committee received 94 applications, a record number over the entire fund history, 45% more than in 2022. Of the total, 50% of the applications fall in scientific research, while 30% were proposals for the dissemination and education of astronomical science. “We are very happy with the increase in applications; this means that astronomy, and particularly this fund, is consolidated as a development tool in the Chilean community”, said Luis Chavarría, ESO representative in Chile, after the results were delivered. Since 1996, the ESO–Government of Chile Joint Committee ...

15 November 2023: The Atacama Large Millimeter/submillimeter Array (ALMA), in which ESO is a partner, has achieved the highest resolution observations since it began operations. During a technical test, a team of experts from the Joint ALMA Observatory (JAO) in Chile, the National Astronomical Observatory of Japan (NAOJ), National Radio Astronomy Observatory (NRAO) in the USA, and ESO, imaged an evolved star with a resolution of 5 milliarcseconds. This shows ALMA can be used by astronomers to observe objects in detail equivalent to seeing a 10-metre-long bus on the Moon. ALMA consists of 66 antennas which can be arranged in different positions across the high-altitude Chajnantor plateau in Chile. Each is equipped with receivers that allow it to observe radio waves in different frequency ranges, or bands. ALMA’s resolution increases both as the maximum separation between antennas increases and as the frequency of the observations increases. The new images were obtained with the ...

6 November 2023: Spearheaded by the European Space Agency (ESA), the Zero Debris Charter aims to address the increasing risks of space debris in Earth’s orbit. Released today at the Space Summit 2023 in Seville, Spain, the charter represents a collaboration between more than 40 space stakeholders, including the European Southern Observatory (ESO). Crucially for ground-based astronomical organisations like ESO, the charter recognises the adverse effects space debris can have on dark and quiet skies and seeks to mitigate them “to the greatest possible extent”. The Zero Debris Charter is an important agreement outlining both principles and actions to prevent and mitigate space debris — the defunct objects in Earth’s orbit such as dead satellites, rocket fragments or other broken-up machinery. As recognised in the charter, space debris can compromise the safety of space activities, as well as any technological or social benefits that these activities provide to humankind. The agreement comes at ...

19 October 2023: Chile, ESO’s partner country and host to all three of its astronomical observatories, has yesterday issued a new standard to protect the country's dark skies, which are considered unique in the world. The new standard, established by the Chilean Ministry of the Environment, aims to control emissions from outdoor lighting and signs, to prevent pollution from artificial luminosity, protecting the astronomical quality of the night skies, the health of people, and biodiversity [1] in Chile. The standard will regulate light emissions throughout Chile, expanding the norm that is already in force in the regions of Antofagasta, Atacama and Coquimbo, where all ESO observatories are located, among other international centres present in the country. Public lighting in Chile will be adjusted to favour the composition of light in amber tones and limit blue light. Likewise, advertising and sports lighting will be subject to schedule control, which, for example, will allow greater ...

16 October 2023: Last week, a time capsule commemorating ESO staff, science, technology and cooperation between ESO and Chile was buried in a ceremony at the construction site of ESO’s Extremely Large Telescope (ELT), on Cerro Armazones in the Chilean Atacama Desert. The capsule was sealed at the first stone ceremony in 2017, when construction on the soon-to-be “world’s biggest eye on the sky” began. Serving as a symbolic message to future generations, it contains mementos from Chilean authorities, including a plaque from the then President of Chile, Michelle Bachelet Jeria, about opening the skies of the country to the questions of an entire planet, as well as drawings from Chilean children featuring the Universe, ESO telescopes and northern Chile landscapes. The capsule also includes a mosaic of photographs of ESO staff and a copy of a book describing the future scientific goals of the telescope [1]. Covering it is an engraved hexagon ...

12 October 2023: On 6 November 1963, the European Southern Observatory (ESO) and the Republic of Chile signed an agreement which started a cooperation in astronomy that had tremendous worldwide impact. This relationship enabled the establishment of unique observatories in the Atacama Desert, such as La Silla, Paranal and ALMA, and the development of strong astronomical communities and cutting-edge scientific breakthroughs. Yesterday, ESO Council and staff, along with diplomats from ESO Member States, Chilean authorities and the scientific community, held a ceremony at the ESO offices in Santiago — the first of several celebrations to mark 60 years of the agreement. The history of Chile and ESO is marked by several milestones that have strengthened this partnership. The first observatory established by ESO was La Silla, inaugurated in 1969 in the region of Coquimbo, 600 km north of Santiago. Here, ESO currently operates some of the most productive optical telescopes of their class. ...

27 September 2023: Francesca Primas, Full Astronomer at ESO, has been honoured with the inaugural Nancy Grace Roman Award by the Astronomical Society of the Pacific (ASP). Primas is the first person to receive this award, which was introduced this year to recognise an “individual or group for significant contributions to promoting gender equity and inclusion in astronomy and related fields”. Primas is a renowned astrophysicist researching the chemical evolution of the Milky Way and its satellite galaxies. She’s also a trailblazer in promoting gender equity in astronomy in general and at ESO specifically. Some 15 years ago, she conducted a study on the status of women at ESO to evaluate the gender distribution across the organisation. The results were disappointing, with the study finding only 18% of staff members identified as female, but served as the basis for discussion and future action to promote diversity, equity and inclusion at ESO. Primas spearheaded ...

25 September 2023: Progress in the Cherenkov Telescope Array Observatory (CTAO) –– the world’s most powerful ground-based gamma-ray observatory –– will be bolstered by a recent funding pledge from its governing bodies. On 6 September 2023, the CTAO’s Board of Governmental Representatives and the CTAO gGmbH Council, of which ESO is a member, met to agree on the next steps to advance the CTAO to its construction phase. As part of their unanimous commitment to the progress of the project, all members agreed on a foreseen endorsement of up to approximately 30 million euro for 2024. This significant increase in the CTAO’s funding will allow it to build new infrastructure and double the workforce. The CTAO will consist of two arrays of telescopes: CTAO-North in La Palma, Spain, and CTAO-South at ESO’s Paranal Observatory in Chile. After extensive design and pre-construction activities, such as testing a prototype telescope in the northern site, the ...

14 August 2023: An international team of astronomers and engineers at the Atacama Large Millimeter/submillimeter Array (ALMA), in which ESO is a partner, have made the first measurements using new receivers installed on multiple ALMA antennas. The receivers allow ALMA to observe within the final frequency range — with wavelengths between 2.6 to 4.5 millimetres (67-116 GHz) — for which it was designed. This so-called “Band 2” opens a new window into our cosmic origins, allowing measurements that reveal how distant stars and galaxies form, all the way down to the origins of planets and the building blocks of life. ALMA, located on the Chajnantor Plateau in Chile, consists of a total of 66 antennas, each equipped with an arsenal of highly sensitive receivers. Each receiver type observes within a particular band, or range of wavelengths in the submillimetre/millimetre region of the electromagnetic spectrum. In total these bands cover a window from 0.3 ...

24 July 2023: ESO and the Square Kilometre Array Observatory (SKAO) have signed a cooperation agreement, covering areas such as strategy and governance, communications, international relations, scientific coordination and sustainability, diversity and inclusion. It was signed today at ESO’s Headquarters in Garching, Germany, by SKAO Director General Phil Diamond and ESO Director General Xavier Barcons. SKAO is an intergovernmental organisation that aims to build and operate cutting-edge radio telescopes to transform our understanding of the Universe. There is, therefore, considerable overlap between the interests of SKAO and ESO, whose mission is to design, build and operate advanced ground-based observatories and to foster international collaboration for astronomy. In fact, ESO and SKAO have had close-cooperation links since the establishment of SKAO, with scientists, engineers and administrators of both organisations collaborating on a regular basis. For example, ESO and SKAO have worked together to raise awareness about the need to protect the dark and quiet ...

20 July 2023: The ESO Annual Report 2022 is now available. It presents the many activities of ESO during the year. The contents include, among other topics: The steady progress of the construction of ESO’s Extremely Large Telescope (ELT), both on Armazones and in Europe. Highlights of the latest scientific research enabled by ESO’s facilities, which once again resulted in the publication of more than 1000 refereed papers during the year. Among these highlights, the release of the image of the shadow of the Sgr A* black hole by the Event Horizon Telescope Consortium (using both ALMA and APEX). Commissioning of ERIS (the Enhanced Resolution Imager and Spectrograph) at the VLT and NIRPS (the Near InfraRed Planet Searcher) at the 3.6-metre telescope, as well as the progress on all other instrument projects. ALMA development, including the Band 2 receiver project and the Wide-Band Sensitivity Upgrade. The start of operations of the new Paranal–Armazones ...