Probing the early and present Universe with Planck
This multi-colour all-sky image of the microwave sky has been synthesized using data spanning the full frequency range of Planck, which covers the electromagnetic spectrum from 30 to 857 GHz.
The grainy structure of the CMB, with its tiny temperature fluctuations reflecting the primordial density variations from which the cosmic web originated, is clearly visible in the high-latitude regions of the map, where the foreground contribution is not predominant - this is highlighted in the top inset, from the 'first light' survey.
A vast portion of the sky, extending well above and below the Galactic Plane, is dominated by the diffuse emission from gas and dust in the Milky Way, which shines brightly at Planck's frequencies. While the galactic foreground hides the CMB signal from our view, it also demonstrates the extent of our Galaxy's large-scale structure and its emission properties. The two central insets emphasize the strength of the Galactic Plane's emission, as well as the rich texture of loops and spurs emanating from it.
Two extremely active regions of star formation are also highlighted, namely the giant molecular clouds of Perseus (left), and Orion (right).