The Plancky map of the Coma cluster obtained by combining the HFI channels from 100 GHz to 857 GHz. North is up and west is to the right. The map is corrected for the additive constant y_off. The final map bin corresponds to FWHM = 10′. The image is about 130  arcmin × 130  arcmin. The contour levels are logarithmically spaced by 2^1/4 (every 4 lines, y increases by a factor 2). The outermost contour corresponds to y = 2 × σ_noise = 4.6 × 10^-6. The green circle indicates R₅₀₀. White and black crosses indicate the position of the brightest galaxies in Coma. The white sectors indicate two regions where the y map shows a local steepening of the radial gradient (see Sect. 7 and Fig. 6).