Planck is Europe's first mission to study the Cosmic Microwave Background, the relic radiation from the Big Bang, which occurred about 14 thousand million years ago. This radiation was initially energetic, but with the continued expansion of the Universe, what was once a searing fireball has since cooled to become a background sea of microwaves. Planck rotates to scan the sky and measure the temperature variations across this microwave background with much better sensitivity, angular resolution and frequency range than any previous satellite, giving astronomers an unprecedented view of our Universe when it was extremely young, just 300 000 years old.
The spacecraft was lofted into space in a double launch, together with ESA's Herschel space telescope, on board an Ariane 5 ECA launcher on 14 May 2009. Planck is 4.2 m high and has a maximum diameter of 4.2 m; the Planck Mission Operations Control Centre (MOC) is located at ESOC, Darmstadt, Germany.
More information: http://www.esa.int/planck
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