Composite image of the field of view mapped in the Horsehead nebula (Barnard 33). Left: horsehead nebula and adjacent H II region IC 434 imaged by Euclid Early Release Observations (ESA/Euclid/Euclid Consortium/NASA). Right: zoomed-in image of the edge of the Horsehead nebula imaged with data combined from the ALMA 7 m and the IRAM 30 m telescopes. The emission of different N-bearing molecules are represented: CH₃CN (J_K = 6₀–5₀, in green) and HC₃N (J = 11–10, in blue). The emission from hot ionized gas is also shown, traced by the Hα line (in red) observed with the 0.9 m KPNO telescope (Pound et al. 2003). The average beam size of the ALMA 7 m+30 m observations and a physical scale reference are shown in the bottom left and bottom right corner, respectively.