The European Space Agency’s Euclid space telescope has captured the largest close-up image ever taken of the Milky Way’s central region. Built from 26 hours of observations, the massive mosaic reveals more than 60 million stars and is expected to become a valuable resource for exoplanet research.
The telescope was launched to study the large-scale structure of the universe and help scientists investigate dark matter and dark energy. Its latest achievement, though, focuses much closer to home. By observing the Milky Way’s galactic bulge, the mission has produced one of the most detailed surveys ever made of the galaxy’s densely populated center.
Thegalactic bulge is one of the most crowded regions in the sky. Millions of stars overlap from our point of view, making it difficult to separate them clearly. The new image shows that Euclid can handle that challenge remarkably well, delivering a detailed view of a region that remains a key target for astronomers.
More Than 60 Million Stars In A Single Image
The mosaic was created from observations made in March 2025. Over a cumulative 26-hour period, the telescope pointed its visible-light camera toward the galactic bulge nine times, with each observation covering an area of sky larger than the full Moon.
As stated by the European Space Agency (ESA), the final image contains more than 60 million stars. The telescope’s performance is particularly notable given that it was originally designed to observe distant galaxies rather than the dense stellar environment found at the center of the Milky Way.
ESA noted that Euclid’s instruments were sensitive enough to separate individual stars throughout the field while maintaining the level of precision required for scientific analysis.
A Useful Tool For Exoplanet Research
The new dataset is expected to support studies of exoplanets, especially those detected through gravitational microlensing. This method relies on the alignment of two stars along an observer’s line of sight. As the foreground star passes in front of a more distant star, its gravity bends and magnifies the background star’s light.
If a planet orbits the foreground star, it can produce an additional signal in the light pattern, allowing astronomers to detect its presence. As mentioned in the release, nearly 300 exoplanets have been discovered through microlensing during the past 20 years, all using ground-based telescopes and observations directed toward the center of the Milky Way.
“During the last twenty years, almost 300 exoplanets have been discovered using this technique, all with ground-based telescopes and all towards the centre of our galaxy. This image from Euclid includes 51 known planetary systems – and it will assist in studying many more that will be found,” explained Jean-Philippe Beaulieu, who initiated the Euclid Galactic Bulge Survey and co-led the Euclid Consortium’s exoplanet working group.
While telescope’s observing campaign was not long enough to capture a complete microlensing event, it still collected valuable information on known stars and planetary systems within the survey region.
A Head Start For Future Planet Hunters
The observations could become particularly valuable once NASA’s Nancy Grace Roman Space Telescope begins its own search for exoplanets. The mission is currently scheduled to launch no earlier than Aug. 30 aboard a SpaceX Falcon Heavy rocket from Kennedy Space Center in Florida.
Roman will use microlensing to find new worlds, often in the same region of the galaxy observed by Euclid. That means astronomers now have a detailed record of many stars before future microlensing events take place.
As noted byNatalia Rektsini of the Paris Institute of Astrophysics, who led the release of the galactic bulge survey data, future observations can be compared with Euclid’s images to track stellar motions over time.
“Since Euclid can clearly separate individual stars, one can then measure how fast they move over time, and use that information to confirm the existence of a planet and determine its mass. This would not be possible with data from one point in time,” she said.
The newly released mosaic therefore serves as both a detailed portrait of the Milky Way’s center and a scientific reference that researchers will be able to revisit as new planetary discoveries emerge from this region of the galaxy.
