Longitude distribution of emission components along the Galactic plane at b = 0° in the range l = 90° to 270°. The data are all smoothed to 1° resolution except the gamma-ray data with a FWHM of 88′. The components shown are 408 MHz (mainly synchrotron), 28.4 GHz (similar AME and free-free), 70.4 GHz (mainly free-free), 353 GHz (dust), CO, gamma-rays, pulsar numbers (representing supernovae), and 100 μm. The gamma-ray and pulsar data are at N_side = 64 and N_side = 32 respectively, to account for the relatively low sampling. The pulsar data are uniformly surveyed from l = 270° to 40°; at l = 40° to 90° the survey sensitivity is lower. The Galactic centre is off-scale so that the diffuse emission can be displayed.