Wednesday, July 2, 2008

Mars Express


Europe’s mission to Mars
  • In operation
  • Launched 2 June 2003
  • Mission extended until May 2009
With its dramatic images of canyons, craters and frozen lakes, Mars Express has sent back scientific data of unprecedented quality. This is the European Space Agency’s (ESA) first mission to Mars. The spacecraft is investigating the surface and atmosphere, including volcanic and geological activity, the presence of water and the planet’s climate.

The UK has been involved in the design, operation and science of Mars Express. Since arriving at Mars in December 2003, the achievements of Mars Express have been numerous. Highlights include evidence for volcanic and glacial activity on Mars from early in the planet’s history until relatively recently.

One of the mission’s main objectives has been to detect the presence of water – an essential component if there is any chance of finding signs of life. Sub-surface radar sounding has revealed underground water-ice and buried impact basins. An examination of the planet’s surface has provided evidence for a history of water on Mars – water is now known to have been abundant on the planet in the past.

Mars Express may also have detected methane in the atmosphere. This could be an indicator of volcanic activity. The discovery of methane might even suggest there is life on the Red Planet. Any life would be in the form of extremely primitive micro-organisms rather than ‘little green men’.

UK scientists have also been at the forefront of efforts to investigate the auroras discovered in the Martian atmosphere. Because Mars doesn’t have a magnetic field, researchers have concluded that the auroras come about as a result of local magnetic fields generated in the planet’s crust. This makes them unique in our Solar System.

One aspect of the mission that has not been successful was the plan to land a probe on Mars. Built in the UK, Beagle 2 would have drilled into the surface to look for ‘signatures’ of life. Unfortunately, no signals have been detected since Beagle 2 left the Mars Express spacecraft in December 2003 to begin its descent to the Martian surface and its fate is unknown.

European space scientists have confirmed plans to return to Mars as part of the Aurora programme – this time with a rover. The first Aurora mission, ExoMars, is due for launch in 2013.

For the latest news visit the ESA Mars Express mission website.


Mission facts

  • Mars is the most Earth-like planet in the Solar System.

  • The planet is named after the Roman god of war, because of its blood-like colour. The orange-red appearance results from soil rich in iron oxide (rust).

  • Mars boasts scenery on a massive scale. Running roughly along the equator there is an enormous set of 4,000 km long canyons called the Valles Marineris.

  • Mars also has the highest volcano in the Solar System. Three times as high as Mount Everest, Olympus Mons stands at 26 km above the surrounding plain.

  • There is strong evidence for the existence of a frozen sea just below the dusty surface, close to the equator. Images show a flat plain, part of the Elysium Planitia, which is covered with irregular blocky shapes that look just like the broken blocks of sea ice that float off the Antarctic coast.

  • Mars Express was given its name because of the speed with which it was developed. The spacecraft was built and launched in record time, and cost far less than other comparable missions.

  • Beagle 2 was named after the ship in which Charles Darwin sailed when formulating his ideas about evolution.

  • Mars Express completed its planned mission after one Martian year (or 687 Earth days). However, in September 2005, ESA took the decision to extend the mission by an additional Martian year, starting in December 2005.

Technology

Each of the seven instruments on board the orbiter focuses on a different aspect of Mars and its atmosphere:

  • ASPERA (energetic neutral atoms analyser) studies how the stream of charged particles coming from the Sun – the solar wind - interacts with the planet's atmosphere. This will help to explain how water vapour and other gases could have escaped from Mars in the past.

  • HRSC (High Resolution Stereo Camera). The HRSC is imaging the entire planet in 3-D and with a full-colour resolution of about ten metres. Selected areas are being imaged at 2 m resolution. The pictures are being used to produce a map showing exactly where different rocks and minerals are located.

  • MaRS (Mars Radio Science Experiment) is using radio waves to measure the planet's gravity, interior structure and surface roughness.

  • MARSIS (Mars Advanced Radar for Subsurface and Ionosphere Sounding) is a ground-penetrating radar instrument. It enables the orbiter to probe two kilometres beneath the planet’s surface. MARSIS is made up of three antennas: two booms 20 m long, and another seven metres long at right angles to the first two. MARSIS has been able to locate pockets of water that lie below the surface.

  • OMEGA (infrared mineralogical mapping spectrometer) will tell us which minerals make up the surface of Mars and which molecules are present in the planet's atmosphere. Information from this instrument will help us understand what effect water has had on the planet.

  • PFS (Planetary Fourier Spectrometer) is measuring the level of water vapour and ozone in the planet's atmosphere more accurately than any previous mission has managed to do. Because Mars and Earth have so much in common, these findings will also help scientists to understand more about our own atmosphere.

  • SPICAM (ultraviolet and infrared atmospheric spectrometer) will measure the atmosphere of Mars including its ozone content.

UK involvement

The UK, through the Science and Technology Facilities Council (STFC) funding, is involved in three of the instruments on board the spacecraft.

The ASPERA instrument, which is studying how the solar wind interacts with the Martian atmosphere, was built with the involvement of University College London’s (UCL) Mullard Space Science Laboratory and the STFC Rutherford Appleton Laboratory (RAL).

The High Resolution Stereo Colour Imager (HRSC) involves UCL and the Open University (OU).

The ground-penetrating radar, MARSIS, benefits from the expertise of UCL, Queen Mary University of London and the University of Bristol.

The Beagle 2 lander was designed and built in the UK. Astrium Limited and a team from the OU developed Beagle 2 with help from other science and industry partners.

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