Cosmic Microwave Background
The Cosmic Microwave Background (CMB) is the residual thermal radiation from the early universe, dating back to approximately 380,000 years after the Big Bang. It provides a snapshot of the universe at that time, offering critical evidence for the Big Bang theory.
Source: esa.int
APODs including "Cosmic Microwave Background"
Microwave Milky Way
09/07/2010
Seen from our edge-on perspective, the Milky Way Galaxy sprawls across the middle of this false-color, all sky view. The expansive microwave map is based on 1 year's worth of data from instruments onboard the sky-surveying Planck spacecraft. Remarkably, the bright stripe of gas and dust clouds along the galactic plane and the galaxy's enormous arcing structures seen at microwave energies are hundreds or thousands of light-years away, while the mottled regions at the top and bottom represent the Cosmic Microwave Background (CMB) radiation, some 13.7 billion light-years distant. Left over from the Big Bang, fluctuations in the CMB reflect the origins of structure in the evolving universe. Analyzing the microwave data, Planck scientists plan to separate the contributions of the Milky Way and CMB radiation. The work will ferret out the characteristics of the CMB across the entire sky and glean information about the make up of our Milky Way Galaxy.