The HERSCHEL satellite is about 7 metres hight and 4.3 metres width, for a launch mass of about 3.25 tonnes. Alcatel in Cannes, France, lead the industrial consortium which built the HERSCHEL satellite with Astrium in Friedrichshafen, Germany, and Alenia in Turin, Italy.

The HERSCHEL satellite is manufactered in parallel with PLANCK satellite by a common project team. HERSCHEL and PLANCK will be simultaneously launched in 2009 by an ARIANE 5 launcher. The transit time towards Lagrange L2 point will be approximately 4 months. The satellite should operate for at least 3 years.

PACS (Photoconductor Array Camera and Spectrometer) which is composed of an imaging photometer containing two bolometer matrix at 300 mK (Blue: 60 to 130 µm ; Red: 130 to 210 µm) and a spectrometer constituted of two stressed Ge:Ga photoconductor in the bands 57 to 210 µm.
SPIRE (Spectral and Photometric Imaging REceiver) which is composed of an imaging photometer (R~3) on three simultaneous bands at 250 µm (three bolometer matrix 32x32 at 300 mK), 350 µm (242) and 500 µm (162) covering a field of view of 4'x4' and a medium resolution FTS spectrometer (R~10-1000) at 200-300 µm (162) and 300-670 µm (122) covering a field of view of 2'x2' (two bolometer matrix at 300 mK).
HIFI (Heterodyne Instrument for FIrst) which will realize very high resolution spectroscopy. It contain five mixers with SIS junction, double polarity, operating in the 480 to 1250 GHz band, two HEB mixers, simple polarity, operating in the 1410 to 1910 GHz band and an AOS spectrometer as well as autocorrelators in parallel on 4 GHz.