Euclid Telescope Captures Most Detailed Image of Milky Way's Center

The European Space Agency's Euclid space telescope has captured the largest and most detailed visible-light image ever obtained of the Milky Way's central bulge. The mosaic, composed of nine separate pointings, contains more than 60 million stars, along with nebulae and star clusters. This image will allow scientists to confirm exoplanets via gravitational microlensing and measure their masses more precisely.

Although Euclid was designed to observe billions of distant galaxies, its visible-light camera is sensitive enough to resolve individual stars in the crowded and bright galactic center. On March 23, 2025, Euclid turned toward the galactic bulge and captured the image in just 26 hours. Each of the nine pointings covers an area larger than the full moon.

Euclid's visible-light image quality is comparable to Hubble's, but each Euclid pointing covers 270 times more area in a few hours. The Keck Observatory would need about 2,000 hours to observe the same mosaic.

The new image is ideal for microlensing searches. Jean-Philippe Beaulieu, who led the observing campaign, noted that nearly 300 exoplanets have been discovered via microlensing in the past 20 years, and Euclid's image includes 51 known planetary systems. While Euclid's short campaign couldn't detect new events, it provides data to measure masses of known and future planets.

Natalia Rektsini, who led the data publication, emphasized that Euclid has already captured stars involved in future microlensing events before they align with planets. This means Euclid data will serve as a reference archive for missions like the Nancy Grace Roman Space Telescope, enabling more detailed exoplanet studies and precise mass measurements.