PLANCK mission is an astronomy mission of the ESA scientific program. PLANCK will carry 2 instruments at the focal plane, one of them being HFI (High Frequency Instrument) realised in partnership between CNES and several international laboratories, under prime contractorship of the IAS (Institut d'Astrophysique Spatiale) in Orsay.

PLANCK is dedicated to the study of the origin of the Universe in the submillimeter domain. It will realise a cartography of the anisotropies of the CMB (Cosmic Microwave Background) which acts as the radiation of a black body at 2.73 K, covering all the sky with an angular resolution of about 5 arcsec (by comparison to the 7° of its predecessor Cobe) and a sensitivity in temperature of about 2x10^-6.