Galactic dust emission is concentrated in a bright band along the Galactic plane, with clumps associated with dust-rich regions. It is a foreground with a <Frequency spectrum>[spectrum] different from a 2.7 K blackbody, so multi-frequency observations can help separate it from the CMB. The schematic below illustrates its geometry rather than reproducing observed sky data.

Solution

Past exam of the short options paper shared by Prelims and Parts A and B of the physics course of the University of Oxford / 2016 / S2 / 3 / a / Solution

 Solution (source code)