Venus Express - Europe’s mission to Venus

• In operation
• Launched 9 November 2005
• Arrived in orbit 11 April 2006
• Undertaking an extended mission

False colour image taken with the Venus Monitoring Camera on board Venus Express
Credit: ESA

The European Space Agency's (ESA) Venus Express mission was first proposed by Fred Taylor from the University of Oxford. It has been in orbit around the planet for more than two Venusian days - equivalent to 500 Earth days. Venus Express is allowing scientists to investigate the world from the top of its thick cloudy atmosphere down to the fiery volcanic surface. The mission has now been extended until at least 2009.

So far, Venus Express has collected a massive amount of data on the planet's atmosphere. It has also examined the planet's interaction with the solar wind - the stream of charged particles coming from the Sun. Venus Express is equipped with the most advanced instruments ever used for atmospheric investigations of Venus.

On the face of it, the planet Venus should be very similar to the Earth, but with its thick clouds, surface temperatures of an average 467°C and 'runaway' greenhouse effect, Venus has evolved very differently. The study of Venus will add to our knowledge of similar processes taking place on Earth. Results from Venus Express could help us understand the threat from climate change.

Achievements of Venus Express include:

• The first clear images of the planet's south pole. These confirm the presence of a spectacular vortex in the atmosphere which looks like a hurricane but with two 'eyes'.
  
  
• The first sets of 3-D information on the structure and dynamics of the sulphuric acid clouds surrounding the planet, temperature maps of the surface and data on the atmosphere at different altitudes.

Venus Express has confirmed the presence of 'UV absorbers'. These absorb a sizeable amount of the ultraviolet solar energy the planet receives. What substances cause this process remains a mystery.

A study of the higher atmosphere has also revealed a high 'haze' which extends some 100 km above the planet.

Visit the ESA website (link opens in a new window) for the latest news on the mission.

Mission facts

• The second planet from the Sun is named after the Roman goddess of love and beauty.
  
  
• Apart from the moon, Venus is the brightest object in the night sky.
  
  
• Venus is only slightly smaller than Earth and has a very similar chemical composition and density. Despite this, it ranks as one of the most inhospitable places in the Solar System.
  
  
• It appears that Venus started out with large amounts of water on the surface and in the atmosphere but this was stripped away by the solar wind - the stream of charged particles from the Sun. The Earth, on the other hand, has a magnetic shield protecting us from the worst of this onslaught.
  
  
• Despite over 20 missions to Venus, we still know very little about the planet. The last mission was the Magellan craft sent by NASA. This produced just one hour's worth of images before it was destroyed by Venus' immense heat.
  
  
• The first successful landing on Venus was over 30 years ago in 1970. The Soviet probe Venera 7 parachuted a capsule of scientific instruments onto the planet's surface.
  
  
• Due to end December 2009.

Technology

Venus Express is carrying a range of instruments to study the atmosphere, plasma and surface of Venus in great detail. Many instruments on this mission are new versions of ones designed for the Mars Express and Rosetta missions. They have been enhanced to withstand the extreme conditions found on Venus.

The instruments on Venus Express will tell us more about the composition and circulation of the planet, and how its atmosphere has changed over the years. This should tell us a lot more about how our own planet and its surroundings have evolved.

ASPERA 4 - Analyser of Space Plasmas and Energetic Atoms - is studying the interaction between the planet's atmosphere and the solar wind. ASPERA 4 is a new version of the ASPERA 3 instrument used on Mars Express.

The Magnetometer, known as MAG, is measuring the strength and direction of the planet's magnetic field to reveal more about the make-up of the atmosphere.

PFS - Planetary Fourier Spectrometer - is an infrared spectrometer designed to analyse the composition of the atmosphere. However, this instrument failed to open so has not been able to produce any useful results.

SPICAV - Spectroscopy for Investigation of Characteristics of the Atmosphere of Venus - is examining the planet's atmosphere by measuring infrared and ultraviolet radiation.

VeRA - The Venus Radio Science - is measuring radio waves to examine the ionosphere, atmosphere and surface of the planet.

VIRTIS - Visible and Infrared Thermal Imaging Spectrometer - is analysing the layers of the atmosphere and the clouds within it.

VMC - the wide-angle Venus Monitoring Camera - is operating in visible, ultraviolet and near-infrared light to map the surface of the planet.

UK involvement

The mission was originally proposed by Professor Fred Taylor and two colleagues from the University of Oxford. Professor Taylor is now an 'interdisciplinary scientist' on the mission.

There is British involvement in five of the instruments. Astrium Limited worked on many parts of the design and testing. SciSys supplied the control system and is supporting spacecraft operations at ESA's Operations Centre in Germany.

Imperial College London and Sheffield University are the co-investigators for the magnetometer, which is measuring the planet's magnetic field.

University College London's Mullard Space Science Laboratory and Science & Technology Facilities Council's Rutherford Appleton Laboratory are co-investigators for the ASPERA instrument.