Noordwijk/Friedrichshafen/Toulouse, 12 February 2009 – The launch of Herschel, the largest space telescope ever built, is being heralded as the year's absolute highlight in astronomy and Airbus Defence and Space is the driving force behind this momentous event.
As part of an international industrial consortium led by Thales Alenia Space, Airbus Defence and Space Friedrichshafen has been responsible for building the payload module, which consists of the cryostat, the optical bench, the scientific instrument harness, the solar array and sun shade (Airbus Defence and Space subsidiary Dutch Space), and finally the interface structure to the telescope and the service module (Airbus Defence and Space Spain). Airbus Defence and Space also integrated the Herschel satellite in Friedrichshafen and tested it at ESTEC, Airbus Defence and Space Toulouse built the telescope with a light weight main mirror (3.5-metre-diameter, 350 kg), the largest mirror ever built for space application, which provided the programme’s primary technical challenge. By contrast, the Hubble telescope is equipped with a 2.4-metre-diameter mirror weighing about 1 ton.
The 3.3-tonne Herschel satellite is currently being transported to the European Space Centre in Kourou, French Guiana. In the next few days, a team of 30 engineers from Airbus Defence and Space will support the preparation of the infrared observatory for its launch onboard Ariane 5. Airbus Defence and Space is also the lead company for the Ariane 5 rocket, which will launch the Herschel telescope on April 16, 2009.
The scientists will use the Herschel space telescope to look billions of light years into space and hence examine in detail the birth of stars. Herschel will be able to observe the evolution of stars and galaxies in the infrared range, at resolutions never before achieved. Herschel will be deployed at the second Lagrangian point (L2), which is around 1.5 million kilometres from Earth.
Herschel will be able to detect even the slightest heat radiating from cosmic dust when it starts condensing to form stars and galaxies. To avoid sensitive instruments being “blinded” by the heat generated by themselves, they have to be cooled to minus 271,5 degrees Celsius, which is less than 2 degrees above absolute zero. The low temperature is attained by 2,300 litres of superfluid helium inside the cryostat being sufficient for more than 4 years of operating in space.
Looking deep into space for a better understanding of the stars
Astronomers can see an entirely different universe in the infrared spectral range than in visible light. The advantage of infrared beams is that they can also penetrate dust clouds and therefore allow scientists critical insights into the birth processes of stars and their planetary systems. A young star begins radiating visible light when it is sufficiently compressed by gravity to set off nuclear fusion processes deep inside it. Just before the fusion begins, the so-called protostar is still very cold and only gives off heat at a few degrees Kelvin. Researchers are especially curious about this radiance, as it provides information on a star's early development stage.
Another goal of the researchers is to analyze young galaxies that are located billions of light years away from us. They were created a short time after the Big Bang and generated up to one hundred times more stars than is the case in galaxies today. Because the universe is expanding, the light from these “teenage” galaxies is shifted to longer wavelengths, an event referred to by astronomers as a spectral red shift. The radiation from these young galaxies, billions of light years away, is therefore predominantly in the infrared part of the spectrum – and this is precisely the range in which the Herschel sensors work.
Using high-resolution spectroscopy, Herschel will also examine the composition of the surfaces and atmospheres of planets.
The space telescope was named after Friedrich Wilhelm Herschel (1738-1822), who discovered the planet Uranus and who also identified infrared radiation in 1800, and his sister Caroline Herschel (1750 – 1848), who discovered 8 comets and 3 nebulae.
Airbus Defence and Space, a wholly owned subsidiary of AIRBUS Group, is dedicated to providing civil and defence space systems and services. In 2007, Airbus Defence and Space had a turnover of €3.5 billion and 12,000 employees in France, Germany, the United Kingdom, Spain and the Netherlands. Its three main areas of activity are Airbus Defence and Space for launchers and orbital infrastructure, Airbus Defence and Space for spacecraft and ground segment and its wholly owned subsidiary Airbus Defence and Space for the development and delivery of satellite services.
AIRBUS Group is a global leader in aerospace, defence and related services. In 2007, AIRBUS Group generated revenues of €39.1 billion and employed a workforce of more than 116, 000.
Jeremy Close (Airbus Defence and Space UK) Tel.: +44 (0)1 438 77 3872
Matthieu Duvelleroy (Airbus Defence and Space FR) Tel.: +33 (0) 1 77 75 80 32
Mathias Pikelj (Airbus Defence and Space GER) Tel.: +49 (0) 7545 8 9123
Francisco Lechón (Airbus Defence and Space SP) Tel.: +34 91 586 37 41