The Les Houches school of physics has always played a pioneering role in the development of French and European science since its birth. In our field, it can be noted the sessions held in 1974 and 1983 (physics and chemistry of the interstellar medium) to prepare the community to IRAM, in 1991 and 1998 for ISO, in 1990 for the teledetection and space use of heterodyne techniques (Odin, SMOS and MIRO on Rosetta) and in 2007 for the Herschel venture.
For the first time, three complementary techniques will be used on the same spacecraft to observe the Far Infrared domain that cannot be observed from the ground due to atmospheric opacity: coherent detection techniques, spectrophotometry and imaging at Terahertz frequencies. Most of the laboratories working in these technologically difficult areas (experiments at 2 Kelvin are complicated enough in the laboratory, but in space it is a real challenge) have built these instruments in worldwide consortia.
This session has been supported by CNRS, INSU, CEA, CNES, ESA, MESR, Observatoire de Paris, Observatoire de Marseille-Provence and Université Joseph Fourier. P.J. Encrenaz, Herschel Mission Scientist.