COBE/DIRBE image of M31. Each field represents 5° × 5° of the DIRBE, mission‐averaged data sets in each band. The DIRBE images have been normalized to 1.0 for the brightest pixel and logarithmically stretched so that the residual background emission after background subtraction can be seen. The peak intensities after background subtraction are 2.2, 1.9, 1.1, 0.55, 1.8, 1.9, 9.1, 23.6, and 17.2 MJy sr⁻¹ for the 1.25–240 μm DIRBE bands. The stretching factors in these logarithmic gray‐scaled images are 7:1 for 1.25–3.5 μm; 5:1 for 4.9 μm; 1:1 for 12, 25, 140, 240 μm; 3:1 for 60 μm; and 4:1 for 100 μm.