Tim Furniss/LONDON

Alcatel Space has been selected by the European Space Agency (ESA) to design, build, test and launch Herschel and Planck science satellites together aboard an Ariane 5E-SV booster in February 2007. The $332 million deal is the largest ever awarded in the field of European space science.

Details of the contract are sketchy and an official announcement is due at next month's Paris air show, but it is known that Astrium and Alenia Aerospazio will be named as major subcontractors.

Herschel, formerly known as the Far Infrared/Submillimetre Space Telescope, is the last Cornerstone mission in ESA's Horizon 2000 programme, while Planck, formerly Cobras/Samba, is Horizon 2000's medium-sized mission.

The experiment module of the Planck satellite will be built by Alcatel, which is also to be responsible for integration and testing of the satellites. Astrium will build the Herschel cryostat and Alenia the service modules of both craft.

The 9m (30ft) long Herschel will be equipped with a 3.5m diameter cryogenically-cooled telescope to study the formation and evolution of stars and galaxies. The 3,300kg (7,270lb) craft, set to operate for three years, will concentrate on shorter wavelengths using spectrometers and photometers. It will have 10 times the sensitivity of ESA's Infrared Space Observatory, which was launched in 1995.

The 1,500kg Planck will study cosmic microwave background radiation left over from the creation of the universe in what is thought to have been a "big bang". It will use a 1.5m diameter telescope with 50 times the sensitivity of NASA's Cosmic Background Explorer, launched in 1989. Planck has a design life of 18 months.

The Ariane 5E-SV, equipped with a 17m-long payload shroud, will place the spacecraft at the L2 Langrangian point of the Earth-Sun system, 1.5 million km (0.9 million miles) from Earth in the opposite direction to the sun.

The 5E-SV will be introduced in 2002. It incorporates a new uprated Vulcain 2 first stage engine.

Source: Flight International