http://www.space.eads.net/web1/press...AGES&langue=en


Venus Express - ready to study Venusian atmosphere
EADS Space Press Release
July 7, 2005

Venus Express, the first European space probe to
investigate the planet Venus has completed the development, integration
and test phase in Toulouse. Venus Express is being manufactured by EADS
Astrium as prime contractor for ESA (European Space Agency). The
research probe is scheduled for launch on board a Soyuz-Fregat rocket
from the Baikonur Cosmodrome (Kazakhstan) in late October 2005. EADS is
the principal shareholder of Starsem, the launch provider, with 35%,
Arianespace holding 15%.

For two Venusian years (500 Earth days), the probe will investigate the
atmosphere of the hottest planet in terms of structure, composition and
dynamics. Venus Express, carrying seven scientific instruments
(spectrometers, imagers and a plasma analyser) will orbit the second
planet of the solar system at an altitude between 250 and 66,000
kilometres by flying above its poles.

Analysing and understanding the prevailing conditions in the atmosphere
and in the near environment of Venus is of critical importance to
understanding long term climatic processes governing the evolution of
life on Earth.

By re-using both Mars Express spacecraft design and the available
instruments from the Mars Express and Rosetta programs, Venus Express
meets the triple challenge of achieving its scientific objectives, cost
efficiency and its unparalleled development schedule.

Venus Express development began in the autumn of 2002. In the last few
months the spacecraft has successfully passed its entire environmental
test campaign in Intespace Toulouse and is currently undergoing the
final functional test prior to Flight Acceptance Review in early July.
Departure to Baikonour is planned by August this year.

Specific solar panels for the mission

As the Venus mission requires guiding the spacecraft towards the sun
the
layout of the solar generators has to be very special. The design is
necessary for the solar arrays to withstand the high temperature loads
encountered during its mission. After Mercury, Venus is the Sun's
nearest planet and consequently solar radiation is considerably higher
than on Earth. Additionally, the solar arrays will be exposed to the
sunlight reflection from the Venusian atmosphere, the so-called albedo.
The solar arrays have been designed and qualified for operating
temperatures between -167?C and +158?C. It delivers a power of 821
watts
in the Earth's orbit and 1,468 watts in the Venusian orbit at the end
of
its four-year mission. Shortly after launch, Venus Express will unfold
its solar arrays which will remain deployed during the whole mission.

EADS Astrium is Europe's leading satellite system specialist. Its
activities cover complete civil and military telecommunications and
Earth observation systems, science and navigation programmes, and all
spacecraft avionics and equipment. EADS Astrium is a wholly owned
subsidiary of EADS SPACE, which is dedicated to providing civil and
defense space systems. In 2004 EADS SPACE had a turnover of EUR2.6
billion
and 11,000 employees in France, Germany, the United Kingdom and Spain.

EADS is a global leader in aerospace, defense and related services. In
2004, EADS generated revenues of EUR 31.8 billion and employed a
workforce
of more than 110,000.


Technical Data

Dimensions: 1.5 x 1.8 x 1.4 m
Mass at launch overall 1250 Kg
Propellant: 570 Kg
Payload 90 Kg

Propulsion:
Thrust of the main engine: 400 N
8 manoeuvring thrusters with 10 N thrust each

Power Supply:
Solar Panels, AsGa cells triple junction, Area ~5 m?, power 1450 W
(at
Venus)
3 Lithium-Ion Batteries with 24 Ah each.

Communication:
Two-way communication system in two wave lengths (S/X band).
Daily data transfer rate: 500 to 4300 Mbits

Launcher:
Soyuz/Fregat