For the first time, a European space probe is to fly to Mars and land on the planet by the end of 2003. "Mars Express" shall investigate whether there was once water on our neighboring planet Mars and whether life was formed at that time.
At 150 million euros, this will be the most cost-effective mission ever undertaken. This has been made possible by the use of proven technologies and developments of the comet probe "Rosetta" and "Mars 96".
Furthermore, the European Space Agency ESA has transferred greater responsibilities to industrial companies. The space company Astrium is the prime contractor for the construction and development of the "Mars Express".
At the end of 1998, the European Space Agency ESA added "Mars Express" to its long-term program "Horizon 2000 Plus". This was the first project of the newly formed series of "Flexible Missions".
These are low-cost missions up to 175 million euros and with short construction times. "Flexible Missions" was ESA's response to the NASA strategy of cheaper, better, faster".
With "Mars Express" ESA wanted to compensate the loss of the Russian Mars mission "Mars 96", in which European scientists were involved to a large extent. In November 1996, the launch of "Mars 96" failed and the probe crashed into the Pacific.
In March 1999, Astrium was awarded a contract for 60 million euros for the construction and development of "Mars Express". Since then, development has been in full swing. "Mars Express"' electrical and functional integration has started in Toulouse. The spacecraft structure has been delivered and the propulsion system is currently being built.
Compared to previous space missions, the industry has assumed more management tasks in "Mars Express". Astrium is, for example, in dined contact with the scientists entrusted with the instrument design and is responsible for the interfaces to the probe.
The leading principle of strict adherence to the cost frame by observing the safety standards, can be achieved by the use of proven technologies. In this respect, the "Rosetta" mission plays an important role. This comet probe was also built by Astrium and is to be launched half a year before "Mars Express".
The hardware and software could be used to a large extent, for example the attitude and orbit control system. ESA was also able to save costs since its control center in Darmstadt employs the technology for the control of ,,Rosetta" for ,,Mars Express". Furthermore, personnel can be saved on account of the fact that members of ESOC will support both missions.
Astrium was also able to use developments in commercial telecommunication satellites. These include the control and propulsion system as well as the structure of electronic sub-units. Another cost-saving factor has been the reproduction of scientific instruments which were to fly on "Mars 96".
These include an infrared camera for the mineralogical analysis of the Martian surface, two spectrometers for the measurement of water vapor, carbon dioxide and ozone in the atmosphere and, in particular, the high-resolution stereo camera (HRSC).
The HRSC is a masterpiece of optics developed and constructed by Astrium as prime contractor. At that time, Astrium had built a second camera model for test purposes. After the accident of "Mars 96", this model was modified for "Mars Express".
Instead of the originally planned ground resolution of up to ten meters, it is to detect pram-sized details from a distance of 250 kilometers. This was made possible by the integration of an additional high-resolution stereo channel developed and built by the German Aerospace Center (DLR). Four other channels supply color images and two channels are required for photometric measurements. A special feature is the possibility to produce stereo images.
With this variety of observation modes, HRSC opens a multitude of prospects to the planet researchers. It will, for instance, be used for searching signs of a former ocean or rivers. For example, it is assumed that the arctic region was previously covered with water. A wide plain is extending there, whose margins resemble coastal lines.
Thanks to its high resolution, the HRSC is able to provide further information in this respect. Recently, U.S. researchers have discovered ditches at the slopes of wide canyons. Water may have emerged from the rocks and flown towards the bottom. In this case, too, the high-resolution images of the stereo camera may provide more information.
A radar on board the Mars Express orbiter is also very interesting from a scientific point of view. It consists of two radar antennas with a length of 20 meters each, which are to scan the Martian surface.
The radar waves will penetrate into the ground to a depth of two to three kilometers and will be reflected from different strata. Thus, different layers of rock, lava and sand can be proven.
In particular, it will be possible to detect reservoirs of water ice in the ground. Any evidence of water is valuable because it helps to reveal the climatic history of our neighboring planet. According to current knowledge, water is the basic prerequisite for the formation of life.
The "Beagle" has landed
The "Beagle 2" lander represents a major technical challenge comprising of the most ambitious science payload to total mass ratio ever attempted. It was named after the ship "HMS Beagle" in which Charles Darwin sailed around the world in the early 1830's. His investigations, in particular on the Galapagos islands, were the inspiration for his theory of evolution. Now, "Beagle 2" is to search for signs of life on Mars - a continuation of man's quest for answers.
Astrium is responsible for the development and construction of the lander. The requirements to be met by the probe are demanding: on the one hand, it shall withstand temperatures up to minus 125 degrees Centigrade - and yet on the other hand, it must be able to resist violent sand storms with speeds up to 400 kilometers per hour.
"Beagle 2", weighing approximately 60 kilograms, will be separated from the mother ship (Mars Express) and fly towards Mars. A heat shield prevents it from burning in the upper atmosphere.
The parachutes will open at a speed of 1,600 km/h and act as another brake. Finally, airbags will inflate to attenuate the impact. This method proved successful in the U.S. "Mars Pathfinder" probe mission.
"Beagle 2" is to land on an even surface which may previously have been the ground of a large lake or river. After landing, first the lid will open like a pocket watch, then the solar arrays will unfold and finally - if everything has worked correctly "Beagle 2" will signal its arrival by sending a song specifically composed for that purpose by the British pop group Blur - The exploration of the landing area will now have started.
A camera will produce a 360-degree panorama of the surrounding area and at the same time, measurement equipment will take recordings of meteorological values such as wind velocity, temperature and solar radiation.
A novelty "mole" situated at the end of its instrument arm will move across the Martian surface until it meets rock, at this point it will burrow into the ground under the rock to a depth of at least one meter. It is here in this previously "undisturbed" location that Beagle 2 will take samples. The samples are then carried back to the lander where on board analysis will search for organic matter.
Additionally, "Beagle 2" will use stereo cameras to detect for scientifically promising rocks, then using it's probe will extend an instrument arm towards these rocks to remove the outer, weathered layer which is likely to be covered with sand.
Having uncovered the rocks surface "Beagle 2" will use its cameras to take microscopic pictures in order to gain information regarding the rocks mineral composition and age.
It will then use its probe, which is equipped with a gas analysis package and mass spectrometer to determine both the chemical and isotopic composition of the rocks. The results of which will reveal whether the rocks are volcanic or sedimentary, the latter being an indication that there was once water in that area - the most likely of places for life to have existed or even still exist today.
It is known that the isotope carbon-12 is increased in the metabolism of earthly living beings. This means they increase the natural relation of carbon-12 to carbon-13. This characteristic feature has helped researchers in Greenland to find fossils in rocks which were 3.8 billion years old. A comparable finding on Mars would be a sensation. Launch with a Soyuz/Fregat at the beginning of June 2003
A launch window of eleven days will be opened for "Mars Express" on June 1, 2003. During that period, the probe is to be launched on a Russian Soyuz and the new upper stage Fregat from the Russian Baikonur Cosmodrome. Thanks to an extremely favorable Mars-Earth constellation, the flight will only take around six months, resulting in the probe reaching the Red Planet at Christmas 2003.
The orbiter will then enter an almost polar, highly elliptic orbit. On this orbit "Mars Express" will approach the surface up to 250 kilometers and withdraw from it up to 11,500 kilometers. For two Earth years, which corresponds to one Martian year, the onboard measurement equipment is to investigate the planet. Within that period the stereo camera is able to map almost the entire planet.
The researcher may thus expect a "rich harvest". Astrium, Europe's leading space company, is a joint venture owned 75% by EADS and 25% by BAE Systems. With 7,500 employees and an annual turnover of 2 billion Euros, its activities cover science and Earth observation applications, telecommunications and ground systems, military programmes and launchers and orbital infrastructure.
Mars Express at ESA
Subscribe To SpaceDaily Express
Mars Express Will Put Phobos In The Spotlight
Paris - Jun 11, 2001
Phobos, the tiny innermost moon of Mars, is to come under unprecedented scrutiny after Europe's mission to Mars goes into orbit around the Red Planet late in 2003. Mars Express is due to pass within 3000 km of the 22 km diameter moon more than 300 hundred times during its first two year nominal mission lifetime.
|The content herein, unless otherwise known to be public domain, are Copyright 1995-2016 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement All images and articles appearing on Space Media Network have been edited or digitally altered in some way. Any requests to remove copyright material will be acted upon in a timely and appropriate manner. Any attempt to extort money from Space Media Network will be ignored and reported to Australian Law Enforcement Agencies as a potential case of financial fraud involving the use of a telephonic carriage device or postal service.|