- Vital structural elements have been built for the
future Gaia mission
The structural frame, which is the only one of its kind in the world,
was created by brazing 17 separate silicon carbide segments together. The work
was a cooperative effort between Astrium and Boostec. Astrium, the prime
contractor for the Gaia mission, designed the frame, whilst Boostec, a
specialist in silicon carbide structures, was responsible for its construction.
The 3-meter diameter frame will provide mechanical support and stability
for all the satellite’s components. These include two telescopes and a 200-kg
focal plane, weighing a total of 670 kg. Boostec performed the machining and
sintering of the segments, before they were brazed together in the
large-diameter furnace first developed to cast the primary mirror for the
Herschel space observatory.
Gaia’s structural frame was made from silicon carbide to ensure that it
provides the satellite’s optical systems with the high level of stability they
require. Gaia’s mirrors will also be made from silicon carbide.
Astrium introduced this ceramic compound for space applications years ago, and
has been developing its optimal usage ever since. Silicon carbide offers
excellent rigidity and stability, with a high level of thermal conductivity and
a low coefficient of thermal expansion, which means it is well suited to the
extremes of space.
The Gaia programme is a key scientific mission for ESA and will be
essential for developing our understanding of the makeup of the stars, and ultimately
the formation and composition of our galaxy.
Through Gaia, it will be possible to determine
the location of 15-magnitude stars down to an accuracy of 10 to 25 millionths
of a second of arc. This is equivalent to an observer in Toulouse
being able to measure the thickness of a hair in Paris, or spot a one euro coin on the surface
of the Moon.
After several feasibility and technical pre-development studies were performed,
Astrium was named the prime contractor for the mission in 2006. The programme
is now going through the manufacturing, assembly and test phase. Astrium in the
UK
is responsible
for developing the Video Processing
unit, as well as validating the onboard
software and the active antenna. The Astrium teams in Friedrichshafen,
Germany, are responsible for
the propulsion and thermal systems, while in Spain, the Barajas centre in Madrid, has recently delivered the carbon
structure of the satellite.
Astrium is
also responsible for the design and development of the satellite's onboard
optical instrumentation.
Astrium, a
wholly owned subsidiary of EADS, is dedicated to providing civil and defence
space systems and services. In 2008, Astrium had a turnover of €4.3 billion and
more than 15,000 employees in France,
Germany, the United Kingdom, Spain
and the Netherlands.
Its three main areas of activity are Astrium Space Transportation for launchers
and orbital infrastructure, Astrium Satellites for spacecraft and ground
segment and Astrium Services for the development and delivery of satellite services.
EADS
is a global leader in aerospace, defence and related services. In 2008,
EADS generated revenues of €43.3 billion and employed a workforce of more
than 118, 000.
Press contacts:
Daniel
Mosely (Astrium UK) Tel.:
+44 (0)1 438 77 8180
Matthieu Duvelleroy (Astrium FR) Tel.:
+33 (0) 1 77 75 80 32
Ralph Heinrich (Astrium GER) Tel.: +49 (0) 89 607 33971
Francisco Lechón (Astrium SP) Tel.:
+34 91 586 37 41
www.astrium.eads.net
