The Herschel Space Observatory


A schematic view of the Herschel Observatory. On the right the location of the science instruments on the focal plane is shown.

Herschel is an ESA cornerstone mission planned as a Space Observatory covering from the far infrared to sub-millimetre spectral domain.
With a 3.5-metres primary mirror, Herschel is the largest telescope ever launched and it hosts three scientific instruments on the focal plane (PACS, SPIRE and HIFI) capable of performing spectroscopy and photometry in the 55-670 µm range.
Herschel is designed to observe the coldest regions in the Universe, providing a new contribution to the understanding of the evolution of the Universe. Herschel pursues the following key scientific objectives:

  • investigate the formation and the evolution of stars, stellar systems and planetary systems;
  • study the formation of early epoch galaxies and their subsequent evolution;
  • elucidate the interaction between successive generations of stars and the interstellar medium;
  • unveil the chemical properties of the interstellar medium as well as of planets, comets and asteroids.

Look at Herschel Mission Overview and Key Programmes presentation and paper. For a spreading of the Herschel Mission see the brochure.

Herschel was launched on 14 May 2009

Herschel was successfully launched from the European Spaceport in Kourou (French Guiana) onboard an Ariane 5 ECA together with the Planck satellite.
Herschel operates in a large (80000 km) orbit around the second Lagrangian point (L2) of the Sun-Earth-Moon system, situated at 1.5 million kilometres away from the Earth.
The Herschel lifetime is determined by the evaporation of the helium contained in the cryostat, allowing at least 3 years of Routine Phase. A nominal estimation of the end of helium content in the cryostat is fixed on December 2012.


The L2 point.
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Layout of Herschel (up) and Plack (bottom)
within Ariane 5 ECA.
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For further information about the Herschel Space Observatory, see the Spacecraft and Observatory Weg pages.