Euclid Space Telescope Unveils Cosmic Treasure Trove: 26 Million Galaxies Captured in First Data Release

Treasure trove of galaxies, glimpses of deep fields

On 19 March 2025, the European Space Agency's Euclid mission releases its first batch of survey data, including a preview of its deep fields. Here, hundreds of thousands of galaxies in different shapes and sizes take centre stage and show a glimpse of their large-scale organisation in the cosmic web. Covering a huge area of the sky in three mosaics, the data release also includes numerous galaxy clusters, active galactic nuclei and transient phenomena, as well as the first classification survey of more than 380,000 galaxies and 500 gravitational lens candidates compiled through combined artificial intelligence and citizen science efforts. All of this sets the scene for the broad range of topics that the dark Universe detective Euclid is set to address with its rich dataset. "Euclid shows itself once again to be the ultimate discovery machine. It is surveying galaxies on the grandest scale, enabling us to explore our cosmic history and the invisible forces shaping our Universe," says ESA's Director of Science, Prof. Carole Mundell. "With the release of the first data from Euclid's survey, we are unlocking a treasure trove of information for scientists to dive into and tackle some of the most intriguing questions in modern science. With this, ESA is delivering on its commitment to enable scientific progress for generations to come." Tracing out the cosmic web in Euclid's deep fields Euclid has scouted out the three areas in the sky where it will eventually provide the deepest observations of its mission. In just one week of observations, with one scan of each region so far, Euclid already spotted 26 million galaxies. The farthest of those are up to 10.5 billion light-years away. The fields also contain a small population of bright quasars that can be seen much farther away. In the coming years, Euclid will pass over these three regions tens of times, capturing many more faraway galaxies, making these fields truly 'deep' by the end of the nominal mission in 2030. But the first glimpse of 63 square degrees of the sky, the equivalent area of more than 300 times the full Moon, already gives an impressive preview of the scale of Euclid's grand cosmic atlas when the mission is complete. This atlas will cover one-third of the entire sky -- 14,000 square degrees -- in this high-quality detail. "It's impressive how one observation of the deep field areas has already given us a wealth of data that can be used for a variety of purposes in astronomy: from galaxy shapes, to strong lenses, clusters, and star formation, among others," says Valeria Pettorino, ESA's Euclid project scientist. "We will observe each deep field between 30 and 52 times over Euclid's six year mission, each time improving the resolution of how we see those areas, and the number of objects we manage to observe. Just think of the discoveries that await us." To answer the mysteries it is designed for, Euclid measures the huge variety of shapes and the distribution of billions of galaxies very precisely with its high-resolution imaging visible instrument (VIS), while its near-infrared instrument (NISP) is essential for unravelling galaxy distances and masses. The new images already showcase this capability for hundreds of thousands of galaxies, and start to hint at the large-scale organisation of these galaxies in the cosmic web. These filaments of ordinary matter and dark matter weave through the cosmos, and from these, galaxies formed and evolved. This is an essential piece in the puzzle towards understanding the mysterious nature of dark matter and dark energy, which together appear to make up 95% of the Universe. "The full potential of Euclid to learn more about dark matter and dark energy from the large-scale structure of the cosmic web will be reached only when it has completed its entire survey. Yet the volume of this first data release already offers us a unique first glance at the large-scale organisation of galaxies, which we can use to learn more about galaxy formation over time," says Clotilde Laigle, Euclid Consortium scientist and data processing expert based at the Institut d'Astrophysique de Paris, France. Humans and AI classify more than 380,000 galaxies Euclid is expected to capture images of more than 1.5 billion galaxies over six years, sending back around 100 GB of data every day. Such an impressively large dataset creates incredible discovery opportunities, but huge challenges when it comes to searching for, analysing and cataloguing galaxies. The advancement of artificial intelligence (AI) algorithms, in combination with thousands of human citizen science volunteers and experts, is playing a critical role. "We're at a pivotal moment in terms of how we tackle large-scale surveys in astronomy. AI is a fundamental and necessary part of our process in order to fully exploit Euclid's vast dataset," says Mike Walmsley, Euclid Consortium scientist based at the University of Toronto, Canada, who has been heavily involved in astronomical deep learning algorithms for the last decade. "We're building the tools as well as providing the measurements. In this way we can deliver cutting-edge science in a matter of weeks, compared with the years-long process of analysing big surveys like these in the past," he adds. A major milestone in this effort is the first detailed catalogue of more than 380,000 galaxies, which have been classified according to features such as spiral arms, central bars, and tidal tails that infer merging galaxies. The catalogue is created by the 'Zoobot' AI algorithm. During an intensive one-month campaign on Galaxy Zoo last year, 9976 human volunteers worked together to teach Zoobot to recognise galaxy features by classifying Euclid images. This first catalogue released today represents just 0.4% of the total number of galaxies of similar resolution expected to be imaged over Euclid's lifetime. The final catalogue will present the detailed morphology of at least an order of magnitude more galaxies than ever measured before, helping scientists answer questions like how spiral arms form and how supermassive black holes grow. "We're looking at galaxies from inside to out, from how their internal structures govern their evolution to how the external environment shapes their transformation over time," adds Clotilde. "Euclid is a goldmine of data and its impact will be far-reaching, from galaxy evolution to the bigger-picture cosmology goals of the mission." Gravitational lensing discovery engine Light travelling towards us from distant galaxies is bent and distorted by normal and dark matter in the foreground. This effect is called gravitational lensing and it is one of the tools that Euclid uses to reveal how dark matter is distributed through the Universe. When the distortions are very apparent, it is known as 'strong lensing', which can result in features such as Einstein rings, arcs, and multiple imaged lenses. Using an initial sweep by AI models, followed by citizen science inspection, expert vetting and modelling, a first catalogue of 500 galaxy-galaxy strong lens candidates is released today, almost all of which were previously unknown. This type of lensing happens when a foreground galaxy and its halo of dark matter act as a lens, distorting the image of a background galaxy along the line of sight towards Euclid. With the help of these models, Euclid will capture some 7000 candidates in the major cosmology data release planned for the end of 2026, and in the order of 100,000 galaxy-galaxy strong lenses by the end of the mission, around 100 times more than currently known. Euclid will also be able to measure 'weak' lensing, when the distortions of background sources are much smaller. Such subtle distortions can only be detected by analysing large numbers of galaxies in a statistical way. In the coming years, Euclid will measure the distorted shapes of billions of galaxies over 10 billion years of cosmic history, thus providing a 3D view of the distribution of dark matter in our Universe. "Euclid is very quickly covering larger and larger areas of the sky thanks to its unprecedented surveying capabilities," says Pierre Ferruit, ESA's Euclid mission manager, who is based at ESA's European Space Astronomy Centre (ESAC) in Spain, home of the Astronomy Science Archive where Euclid's data will be made available. "This data release highlights the incredible potential we have by combining the strengths of Euclid, AI, citizen science and experts into a single discovery engine that will be essential in tackling the vast volume of data returned by Euclid." Notes As of 19 March 2025, Euclid has observed about 2000 square degrees, approximately 14% of the total survey area (14 000 square degrees). The three deep fields together comprise 63.1 square degrees. Euclid 'quick' releases, such as the one of 19 March, are of selected areas, intended to demonstrate the data products to be expected in the major data releases that follow, and to allow scientists to sharpen their data analysis tools in preparation. The mission's first cosmology data will be released to the community in October 2026. Data accumulated over additional, multiple passes of the deep field locations will be included in the 2026 release. About Euclid Euclid was launched in July 2023 and started its routine science observations on 14 February 2024. In November 2023 and May 2024, the world got its first glimpses of the quality of Euclid's images, and in October 2024 the first piece of its great map of the Universe was released. Euclid is a European mission, built and operated by ESA, with contributions from its Member States and NASA. The Euclid Consortium -- consisting of more than 2000 scientists from 300 institutes in 15 European countries, the USA, Canada and Japan -- is responsible for providing the scientific instruments and scientific data analysis. ESA selected Thales Alenia Space as prime contractor for the construction of the satellite and its service module, with Airbus Defence and Space chosen to develop the payload module, including the telescope. NASA provided the detectors of the Near-Infrared Spectrometer and Photometer, NISP. Euclid is a medium-class mission in ESA's Cosmic Vision Programme.

Into the deep (field) with ESA's Euclid 'dark universe' telescope: Space photo of the day

Many galaxies are visible in this deep field exposure, and its just a part of a larger mosaic, zoomed in 16 times. The European Space Agency's (ESA) Euclid mission released its first batch of survey data on Wednesday (March 19), including a preview of its deep fields revealing hundreds of thousands of galaxies in different shapes and sizes. This image, which is just one zoomed-in area from three released mosaics, represents a data release from ESA's Euclid spacecraft that includes numerous galaxy clusters, active galactic nuclei and transient phenomena, as well as the first classification survey of more than 380,000 galaxies and 500 gravitational lens candidates compiled using both artificial intelligence and human efforts. "With the release of the first data from Euclid's sky survey, we are unlocking a treasure trove of information for scientists to dive into and tackle some of the most intriguing questions in modern science," said Carole Mundell, ESA's Director of Science, in a statement. "With this, ESA is delivering on its commitment to enable scientific progress for generations to come." This is from Euclid's Deep Field South, a first glimpse of 63 square degrees of the sky, the equivalent area of more than 300 times the full moon. By comparison, when complete, Euclid's atlas will cover one-third of the entire sky - 14,000 square degrees - in this high-quality detail. In this particular view, galaxies can be identified by their elongated shape or spiral arms. Some are viewed edge-on, while one prominent spiral galaxy at the bottom center is face-on. At the far right, between the middle and top of the image, are galaxies interacting with each other. Galaxy clusters are also seen near the bottom center, where features that are smeared into arcs represent gravitational lensing. The Euclid spacecraft has already seen 26 million galaxies with the farthest up to 10.5 billion light-years away. Through its survey, astronomers will learn more about galaxy shapes and star formation, among other subjects of study. "We will observe each deep field between 30 and 52 times over Euclid's six year mission, each time improving the resolution of how we see those areas, and the number of objects we manage to observe. Just think of the discoveries that await us," said Valeria Pettorino, ESA's Euclid project scientist.

Euclid opens data treasure trove, offers glimpse of deep fields

On 19 March 2025, the European Space Agency's Euclid mission releases its first batch of survey data, including a preview of its deep fields. Here, hundreds of thousands of galaxies in different shapes and sizes take center stage and show a glimpse of their large-scale organization in the cosmic web. Covering a huge area of the sky in three mosaics, the data release also includes numerous galaxy clusters, active galactic nuclei and transient phenomena, as well as the first classification survey of more than 380 000 galaxies and 500 gravitational lens candidates compiled through combined artificial intelligence and citizen science efforts. All of this sets the scene for the broad range of topics that the dark universe detective Euclid is set to address with its rich dataset. "Euclid shows itself once again to be the ultimate discovery machine. It is surveying galaxies on the grandest scale, enabling us to explore our cosmic history and the invisible forces shaping our universe," says ESA's Director of Science, Prof. Carole Mundell. "With the release of the first data from Euclid's survey, we are unlocking a treasure trove of information for scientists to dive into and tackle some of the most intriguing questions in modern science. With this, ESA is delivering on its commitment to enable scientific progress for generations to come." Tracing out the cosmic web in Euclid's deep fields Euclid has scouted out the three areas in the sky where it will eventually provide the deepest observations of its mission. In just one week of observations, with one scan of each region so far, Euclid had already spotted 26 million galaxies. The farthest of those are up to 10.5 billion light-years away. The fields also contain a small population of bright quasars that can be seen much further away. In the coming years, Euclid will pass over these three regions tens of times, capturing many more faraway galaxies, making these fields truly 'deep' by the end of the nominal mission in 2030. But the first glimpse of 63 square degrees of the sky, the equivalent area of more than 300 times the full moon, already gives an impressive preview of the scale of Euclid's grand cosmic atlas when the mission is complete. This atlas will cover one-third of the entire sky -- 14 000 square degrees -- in this high-quality detail. "It's impressive how one observation of the deep field areas has already given us a wealth of data that can be used for a variety of purposes in astronomy: from galaxy shapes, to strong lenses, clusters, and star formation, among others," says Valeria Pettorino, ESA's Euclid project scientist. "We will observe each deep field between 30 and 52 times over Euclid's six-year mission, each time improving the resolution of how we see those areas, and the number of objects we manage to observe. Just think of the discoveries that await us." To answer the mysteries it is designed for, Euclid measures the huge variety of shapes and the distribution of billions of galaxies very precisely with its high-resolution imaging visible instrument (VIS), while its near-infrared instrument (NISP) is essential for unraveling galaxy distances and masses. The new images already showcase this capability for hundreds of thousands of galaxies, and start to hint at the large-scale organization of these galaxies in the cosmic web. These filaments of ordinary matter and dark matter weave through the cosmos, and from these, galaxies formed and evolved. This is an essential piece in the puzzle towards understanding the mysterious nature of dark matter and dark energy, which together appear to make up 95% of the universe. "The full potential of Euclid to learn more about dark matter and dark energy from the large-scale structure of the cosmic web will be reached only when it has completed its entire survey. Yet the volume of this first data release already offers us a unique first glance at the large-scale organization of galaxies, which we can use to learn more about galaxy formation over time," says Clotilde Laigle, Euclid Consortium scientist and data processing expert based at the Institut d'Astrophysique de Paris, France. Humans and AI classify more than 380 000 galaxies Euclid is expected to capture images of more than 1.5 billion galaxies over six years, sending back around 100 GB of data every day. Such an impressively large dataset creates incredible discovery opportunities, but huge challenges when it comes to searching for, analyzing and cataloging galaxies. The advancement of artificial intelligence (AI) algorithms, in combination with thousands of human citizen science volunteers and experts, is playing a critical role. "We're at a pivotal moment in terms of how we tackle large-scale surveys in astronomy. AI is a fundamental and necessary part of our process in order to fully exploit Euclid's vast dataset," says Mike Walmsley, Euclid Consortium scientist based at the University of Toronto, Canada, who has been heavily involved in astronomical deep learning algorithms for the last decade. "We're building the tools as well as providing the measurements. In this way we can deliver cutting-edge science in a matter of weeks, compared with the years-long process of analyzing big surveys like these in the past," he adds. A major milestone in this effort is the first detailed catalog of more than 380 000 galaxies, which have been classified according to features such as spiral arms, central bars, and tidal tails that infer merging galaxies. The catalog is created by the "Zoobot" AI algorithm. During an intensive one-month campaign on Galaxy Zoo last year, 9976 human volunteers worked together to teach Zoobot to recognize galaxy features by classifying Euclid images. This first catalog released today represents just 0.4% of the total number of galaxies of similar resolution expected to be imaged over Euclid's lifetime. The final catalog will present the detailed morphology of at least an order of magnitude more galaxies than ever measured before, helping scientists answer questions like how spiral arms form and how supermassive black holes grow. "We're looking at galaxies from inside to out, from how their internal structures govern their evolution to how the external environment shapes their transformation over time," adds Clotilde. "Euclid is a goldmine of data and its impact will be far-reaching, from galaxy evolution to the bigger-picture cosmology goals of the mission." Gravitational lensing discovery engine Light traveling towards us from distant galaxies is bent and distorted by normal and dark matter in the foreground. This effect is called gravitational lensing and it is one of the tools that Euclid uses to reveal how dark matter is distributed throughout the universe. When the distortions are very apparent, it is known as "strong lensing," which can result in features such as Einstein rings, arcs, and multiple imaged lenses. Using an initial sweep by AI models, followed by citizen science inspection, expert vetting and modeling, a first catalog of 500 galaxy-galaxy strong lens candidates has been released, almost all of which were previously unknown. This type of lensing happens when a foreground galaxy and its halo of dark matter act as a lens, distorting the image of a background galaxy along the line of sight towards Euclid. With the help of these models, Euclid will capture some 7000 candidates in the major cosmology data release planned for the end of 2026, and in the order of 100 000 galaxy-galaxy strong lenses by the end of the mission, around 100 times more than currently known. Euclid will also be able to measure "weak" lensing, when the distortions of background sources are much smaller. Such subtle distortions can only be detected by analyzing large numbers of galaxies in a statistical way. In the coming years, Euclid will measure the distorted shapes of billions of galaxies over 10 billion years of cosmic history, thus providing a 3D view of the distribution of dark matter in our universe. "Euclid is very quickly covering larger and larger areas of the sky thanks to its unprecedented surveying capabilities," says Pierre Ferruit, ESA's Euclid mission manager, who is based at ESA's European Space Astronomy Center (ESAC) in Spain, home of the Astronomy Science Archive where Euclid's data will be made available. "This data release highlights the incredible potential we have by combining the strengths of Euclid, AI, citizen science and experts into a single discovery engine that will be essential in tackling the vast volume of data returned by Euclid."

Euclid spacecraft captures 26 million galaxies in just one week

Serving tech enthusiasts for over 25 years. TechSpot means tech analysis and advice you can trust. What just happened? The European Space Agency's Euclid mission released its first batch of survey data this week, providing a glimpse of hundreds of thousands of galaxies in diverse shapes and sizes, as well as numerous galaxy clusters, active galactic nuclei, and transient phenomena like supernovae and gamma-ray bursts. The data covers a substantial area of the sky in three mosaics, showcasing the mission's capability to explore the large-scale organization of galaxies within the cosmic web. "Euclid shows itself once again to be the ultimate discovery machine. It is surveying galaxies on the grandest scale, enabling us to explore our cosmic history and the invisible forces shaping our Universe," said ESA's Director of Science, Prof. Carole Mundell. She added that this data release unlocks a treasure trove of information for scientists to tackle some of the most intriguing questions in modern science. In just one week of observations, Euclid has identified 26 million galaxies, the farthest located up to 10.5 billion light-years away. These deep fields also contain a small population of bright quasars, some of which are visible from even greater distances. Over the coming years, Euclid will revisit these regions tens of times, capturing many more distant galaxies and making these fields truly 'deep' by the end of the mission in 2030. The initial glimpse of 63 square degrees of the sky previews the scale of Euclid's grand cosmic atlas, which will eventually cover one-third of the entire sky - 14,000 square degrees - in high-quality detail. "We will observe each deep field between 30 and 52 times over Euclid's six-year mission, each time improving the resolution of how we see those areas, and the number of objects we manage to observe," said Valeria Pettorino, ESA's Euclid project scientist. "Just think of the discoveries that await us." Euclid's high-resolution Visible Imaging System (VIS) and near-infrared instrument (NISP) are crucial for measuring galaxy shapes and distances, respectively, providing insights into the large-scale organization of galaxies within the cosmic web. This is essential for understanding dark matter and dark energy, which comprise about 95 percent of the universe. Euclid is expected to capture images of over 1.5 billion galaxies, generating around 100 GB of data daily. Combining AI algorithms and citizen science is vital when analyzing this vast dataset. "We're at a pivotal moment in terms of how we tackle large-scale surveys in astronomy," said Mike Walmsley, a Euclid Consortium scientist. "AI is a fundamental and necessary part of our process in order to fully exploit Euclid's vast dataset." Strong gravitational lenses captured by Euclid Euclid is also a powerful tool for studying gravitational lensing, a phenomenon where light from distant galaxies is distorted by foreground matter. The mission has already identified 500 strong lens candidates, most of which were previously unknown. Euclid aims to capture thousands more such lenses over its mission by combining AI models with citizen science and expert vetting. The mission's first cosmology data will be released in October 2026.

Euclid captures 26 million galaxies in vivid deep field photos - Earth.com

The European Space Agency (ESA) has unveiled the first survey data from its Euclid mission. The images feature a spectacular collection of galaxies, clusters, and deep cosmic fields. This release previews what will soon become one of the largest cosmic maps ever created. Three deep field mosaics highlight hundreds of thousands of galaxies. Their shapes, brightness, and distributions offer a rich visual of the cosmic web. Each observation captures active galactic nuclei and rare, short-lived celestial events. These glimpses already provide hints about the unseen forces shaping our Universe. The Euclid mission mapped 63 square degrees of galaxy-filled sky in just one week. That area equals 300 full Moons. It captured more than 26 million galaxies, including quasars up to 10.5 billion light-years away. The plan is for Euclid to scan each of the three deep regions 30-52 times before 2030. The final sky map will cover one-third of the sky, around 14,000 square degrees. These repeat passes will build an incredibly detailed 3D cosmic atlas that will help researchers explore how galaxies formed and how dark matter shaped their journey. "We are unlocking a treasure trove of information for scientists to dive into," stated Professor Carole Mundell, director of science at the European Space Agency. Each new observation sharpens our view of the universe's large-scale structure. Filaments of normal and dark matter stretch across space like a vast web. These filaments are where galaxies formed and evolved. Euclid's visible and near-infrared instruments offer precision in measuring the shapes and distances of these galaxies. "Just think of the discoveries that await us," noted Valeria Pettorino, an astrophysicist who works on the Euclid Project. ESA scientists expect these images to refine our understanding of dark matter and dark energy. Together, these two invisible components make up 95% of the cosmos. Euclid's massive galaxy dataset requires fresh strategies. Every day, it sends back 100 GB of data. Scientists use AI models and citizen science to process this flood of information. A key result is a new catalogue of over 380,000 galaxies classified by shape and features. "AI is a fundamental and necessary part of our process," noted Mike Walmsley, a Euclid Consortium scientist based at the University of Toronto, Canada, who has been heavily involved in astronomical deep learning algorithms for the past decade. . The Zoobot algorithm, trained by nearly 10,000 volunteers, now classifies galaxies by traits like spiral arms and mergers. This first catalogue is just 0.4% of what Euclid is expected to deliver. When light travels to us from faraway galaxies, it doesn't always move in a straight line. If it passes through matter - like a galaxy or a cluster of galaxies - on the way, the light gets bent. This bending is called gravitational lensing. It's a natural effect caused by gravity and helps scientists detect dark matter, which we can't see directly. Using artificial intelligence and help from human volunteers, Euclid has already found 500 possible examples of strong gravitational lenses. Most of these had never been seen before. By the end of the mission, it is anticipated that Euclid will find about 100,000 strong lenses. That's a hundred times more than we currently know. Each one gives scientists a powerful tool to study how dark matter is spread out across the Universe and how galaxies are shaped by it. "We are combining the strengths of Euclid, AI, citizen science, and experts into a single discovery engine," said Pierre Ferruit, ESA's Euclid mission manager. By March 2025, Euclid had already scanned 2,000 square degrees of the sky, packed with galaxies. That's about 14% of its total planned survey. This work is just the start. The mission will share its first full set of cosmology data in October 2026. That upcoming release will include many repeated observations of three special regions called deep fields. These repeated scans will give scientists a clearer, more detailed view of those distant parts of the Universe. Euclid launched in July 2023. It began regular science work in February 2024. ESA built the spacecraft with support from NASA and companies like Thales Alenia Space and Airbus. The mission is backed by the Euclid Consortium, a global team of over 2,000 scientists from 15 countries. You can now explore the first deep field images through the ESASky platform. This is just the beginning. Euclid will continue to uncover the hidden structure of the cosmos. Details of the latest Euclid Project images are available in this ESA press release. Image Credit: ESA/Euclid/Euclid Consortium/NASA, image processing by M. Walmsley, M. Huertas-Company, J.-C. Cuillandre -- - Like what you read? Subscribe to our newsletter for engaging articles, exclusive content, and the latest updates.