Euclid Telescope Delivers Unprecedented Visible-Light Mosaic of the Mil Way’s Galactic Bulge

On 23 March 2025 ESA’s Euclid telescope devoted 26 hours to imaging the Mil Way’s central bulge. Nine pointings, each larger than the full Moon, were combined into a mosaic that resolves over 60 million stars, nebulae and clusters. Euclid’s visible-light camera matches Hubble’s resolution but covers a field 270 times wider, a task that would take the Keck Observatory about 2 000 hours.

ESA’s Euclid Space Telescope the Most Detailed Image of the Centre of the Milky WayWired MagazineEuclid, the European telescope built to map the dark universe billions of light-years away, spent a single 26-hour stretch staring into the crowded center of the Milky Way and resolved more than 60 mi

Euclid, launched in 2023 to map dark energy and dark matter, was not originally tasked with bulge imaging. Nevertheless, its sharp optics and wide field excel in crowded regions. After fixing stray-ice on the optics, the telescope delivered the high-quality data released on 24 June 2026.

Euclid, the European telescope built to map the dark universe billions of light-years away, spent a single 26-hour stretch staring into the crowded center of the Milky Way and resolved more than 60 mi

• Late 2023 – Euclid reaches orbit and starts commissioning.

ESA’s Euclid Space Telescope the Most Detailed Image of the Centre of the Milky Way

• 23 Mar 2025 – 26-hour bulge imaging.

Euclid, the European telescope built to map the dark universe billions of light-years away, spent a single 26-hour stretch staring into the crowded center of the Milky Way and resolved more than 60 mi

• 24 Jun 2026 – Mosaic released.

ESA’s Euclid Space Telescope the Most Detailed Image of the Centre of the Milky Way

• 30 Aug 2026 (target) – Roman Space Telescope launch, will re-observe the same field.

Euclid, the European telescope built to map the dark universe billions of light-years away, spent a single 26-hour stretch staring into the crowded center of the Milky Way and resolved more than 60 mi

The mosaic resolves > 60 million stars across nine pointings, each larger than the full Moon. Its field of view is 270 × Hubble’s and saves ~2 000 Keck hours; 51 known planetary systems appear in the frame.

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The crowded bulge is optimal for gravitational microlensing, in which a foreground star and any planet briefly amplify a background star’s light. Euclid’s mosaic supplies a precise “before” image of stellar positions and motions, enabling Roman to derive accurate planet masses from later microlensing events. Ground-based surveys have found ~300 such planets; Roman aims to detect > 2 600, including cold, distant worlds beyond other methods.

Euclid, the European telescope built to map the dark universe billions of light-years away, spent a single 26-hour stretch staring into the crowded center of the Milky Way and resolved more than 60 miWired MagazineESA’s Euclid Space Telescope the Most Detailed Image of the Centre of the Milky Way

ESA’s press release noted that the image will let scientists use microlensing to confirm exoplanets and measure their masses more precisely. NASA’s launch brief stressed Roman’s infrared cadence and its plan to repeatedly survey the same Euclid field, producing a coordinated dataset.

Euclid, the European telescope built to map the dark universe billions of light-years away, spent a single 26-hour stretch staring into the crowded center of the Milky Way and resolved more than 60 mi

Sources contain no published criticism. The main limitation is that bulge imaging lies outside Euclid’s original dark-energy mandate, requiring mission time to be repurposed. Engineers report stray-ice issues have been resolved and data quality meets expectations.

Euclid, the European telescope built to map the dark universe billions of light-years away, spent a single 26-hour stretch staring into the crowded center of the Milky Way and resolved more than 60 mi

> “During the last 20 years, almost 300 exoplanets have been discovered using this technique, all with ground-based telescopes and all towards the center of our galaxy. This image from Euclid includes 51 known planetary systems—and it will assist in studying many more that will be found.” — Jean-Philippe Beaulieu, Euclid observing-campaign lead

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Roman’s launch will enable repeated infrared monitoring of the Euclid field, turning the static star catalog into a dynamic exoplanet survey. Together the datasets aim for a comprehensive microlensing planet census and refined models of the Mil Way’s central stellar population.

Euclid, the European telescope built to map the dark universe billions of light-years away, spent a single 26-hour stretch staring into the crowded center of the Milky Way and resolved more than 60 mi