Multi-colour mosaic of the Euclid pointing studied in this work. The area covers 0.58 square degrees. The dark neck of the Horsehead points towards the bright σ Orionis star that is located just outside the field of view. The bright nebular emission crossing the image is the IC 434 H II region, and the bright concentration in the upper left corner is NGC 2023. This paper focuses on the low-reddening part of the field of view that was cleared out by the hot σ Orionis star.