Mosaic of Euclid observations in the northern sky (DR1-Foundation)

ensci_euclid20261112c November 12th, 2026

Credit: ESA/Euclid/Euclid Consortium/NASA, image processing by J.-C. Cuillandre and E. Bertin, CC BY-SA 3.0 IGO

This mosaic from ESA’s Euclid space telescope is based on data released on 12 November 2026 as part of Euclid’s first major data release: DR1-Foundation. The mosaic comprises 740 observations collected in autumn 2024 and spring 2025 as part of the Euclid Wide Survey, and covers 367 deg2 of the northern sky.

The mosaic is nearly 500 gigapixels in size. The small but especially bright oval standing out to the lower left is the spiral galaxy Messier 81, embedded within a wispy tangle of blue-hued clouds (dusty filaments known as ‘galactic cirrus’). Messier 81 lies around 12 million light-years away – close enough for Euclid’s sharp optics to capture its individual stars – and lies at the centre of the Messier 81 group (a group of around 38 galaxies).

[Technical details: This colour image was obtained by combining VIS data and NISP photometry in Y, J, and H bands. VIS and NISP enable observing astronomical sources in four different wavelength ranges. Aesthetics choices led to a combination of these four bands to be cast onto the traditional Red-Green-Blue colour channels used to represent images on our digital screens (RGB). The blue, green, red channels capture the Universe seen by Euclid around the wavelength 0.7, 1.1, 1.3, and 1.7 micron respectively. In the image, the stars have six prominent spikes due to how light interacts with the optical system of the telescope in the process of diffraction. The empty regions within the mosaic were intentionally avoided during the survey due to the presence of very bright stars, which would ‘blind’ Euclid’s sensitive instrumentation. The tilted rectangles in the picture mark regions heavily hit by X-rays and therefore masked out during processing.]

Provider: Euclid

Image Source: https://euclid.caltech.edu/image/euclid20261112c-mosaic-of-euclid-observations-in-the-northern-sky-dr1-foundation

Image Use Policy: CC BY-SA 3.0 IGO or ESA Standard Licence