The ESA FIRST cornerstone mission

FIRST, the 'Far InfraRed and Submillimetre Telescope', is the fourth cornerstone mission in the European Space Agency (ESA) science programme. It will perform photometry and spectroscopy in the far infrared and submillimetre part of the spectrum, covering approximately the 60-670 mu m range. FIRST will carry a 3.5 metre diameter passively cooled telescope (to be supplied by NASA/JPL), and house a science payload complement (to be supplied by instrument consortia) of two cameras/medium resolution spectrometers (PACS and SPIRE) and a very high resolution heterodyne spectrometer (HIFI) in a superfluid helium cryostat. FIRST will be placed in a transfer trajectory towards its operational orbit around the Earth-Sun L2 point by an Ariane 5 (shared with Planck) in early 2007. Once operational FIRST will offer a minimum of 3 years of routine observations; roughly 2/3 of the available observing time is open to the general astronomical community through a standard competitive proposal procedure.