FLUG REVUE December 2002: Europe prepares Mars Express

EUROPE PREPARING EXPRESS MISSION TO MARS

By Matthias Gründer

Mars Express was intended from the outset to serve as a touchstone for new procurement and management concepts that were to be used on future projects and were expected to produce considerable savings, and it is already being said that this objective has been fully accomplished. Experience gained during project definition, development and building of the spacecraft and its lander have contributed materially to making it possible for ESA to continue its ambitious Science Programme despite its financial problems (see FLUG REVUE 8/2002).

Directly after the decision to go ahead with the mission, it was decided that the spacecraft should be developed as quickly as possible so as to take advantage of a favourable window of opportunity as regards launching a Mars-bound space vehicle, that would occur in June 2003. It would then be possible to reach orbit around Mars as early as Christmas that year. Mars Express thus constitutes the first "flexi mission” in the ESA Science Programme.

Starting from the payload capacity of the Russian Soyuz rocket with Fregat upper stage that was earmarked for the launch, the scientific equipment configuration was quickly agreed. The seven primary instruments were to include a high-resolution camera, several spectrometers and a radar to penetrate the surface of Mars. For the first time in the history of Mars research, it would thus be possible from an elliptical orbit trajectory to track down any water that might exist, in the form of subterranean rivers, lakes, glacial ice or permafrost.

In addition, a landing device would be searching for traces of former or even still existing life. This lander, contributed by the UK's Open University, was to be financed by independent sponsors, sparing ESA's tight scientific budget. Until funding was secure, the landing platform remained an option, but the mission could still have taken place without it.

FAST AND COST-SAVING

Under a contract dated 30 March 1999, Matra Marconi Space was commissioned to develop and build the space probe. The project was to be implemented at a total cost of only Euro 60 million and in the short time of only four years, thus to all intents and purposes killing two birds with one stone: on the one hand budgetary constraints were forcing ESA to seek more economical ways of building spacecraft, while on the other hand a Mars mission of all things appeared to be the best opportunity to try out the new, less expensive and faster working methods.

The fact that ESA had already developed and built several experiments for the Russian Mars 96 space probe was a contributory factor here. Although this had crashed into the Pacific shortly after launch following failure of the Proton booster, that experience should not have been in vain. Further savings were to be achieved through shorter development times, reuse of existing equipment, new project management methods and the use of a low-cost launcher rocket.

Selection of the instrument payload by ESA's scientific committees and planning of the mission in industry did not follow one after the other as on earlier missions, but were carried out in parallel. This reduced the time from high-level design through to award of the development contract from about five years to little more than one year. The design and development phases lasted less than four years instead of the previous norm of six years.
This earned the space probe its name, with "Express” referring to the rapid implementation of the project. If at all possible, the satellite should make use of any relevant existing technologies. The technologies concerned were not confined to those developed in connection with the above-mentioned Mars 96 mission but extended to ones used on the Rosetta comet probe, and in the meantime the next planetary probe – Venus Express – is already reusing the Mars Express spacecraft design. The "fast, effective and cost-saving” solution bears not entirely unintended parallels to NASA's Discovery programme (see FLUG REVUE 11/2002).

PRECURSOR TO SERIES PRODUCTION

The novel European concept therefore contains industry themes capable of spanning several projects. Under the new approach, new technologies are first of all tried out on small missions, then employed on larger satellites, and finally they are used for flexible missions later on. This technological cycle makes more flights feasible, securing participants an optimised return.

Final approval for the mission was granted by the ESA Science Programme committee at the beginning of June 1999, after the ESA Council at Ministerial Level had approved the allocation of resources at its Brussels meeting the previous month. With total costs capped at only Euro 150 million, it was clear already at this stage that Mars Express would be the cheapest Mars space probe ever to have been launched for the Red Planet.

The instruments to be carried by the orbiter have now been defined as follows:

·HRSC (High-Resolution Stereoscopic Camera) from Germany, modified second prototype for the Mars 96 mission.
·OMEGA (Observatoire pour la Minéralogie, l'Eau, les Glaces et l'Activité) from France, a spectrometer for the visible and near-infrared spectra
·PFS (Planetary Fourier Spectrometer) from Italy for infra-red light
·MARSIS (Mars Advanced Radar for Subsurface and Ionospheric Sounding) from Italy, surface radar and radar altimeter
·ASPERA (Analyser of Space Plasmas and Energetic Atoms) from Sweden, a sensor for neutral and charged particles
·SPICAM (Spectroscopic Investigation of the Characteristics of the Atmosphere of Mars) from France, an ultraviolet spectrometer
·MaRS (Mars Radio Science Experiment) from Germany, a device to investigate radio-wave propagation.

ESA ALSO FUNDING THE LANDER

At this point, however, funding of the British landing platform, which was to bear the name of Beagle 2 (after the ship on which Charles Darwin once sailed around the world in search of proof for his theory of evolution) was not yet certain. When it transpired at the end of the year 2000 that the necessary Euro 40 million could not be raised by private donations, ESA resolved to take over half of the development costs. It would have been a great pity to launch the space probe without the lander, especially as the value of its scientific research findings would far exceed its financial cost.

In the meantime, by the middle of 2001, over 25 companies from 15 countries and some 200 scientists in the research establishments of all the ESA member states were now working on the project, and a year later assembly of the landing platform commenced. Although the tight schedule is one of the essential features of flexi missions, to an observer it is still amazing that essential construction and test phases are only just beginning. Thus, development of the MARSIS radar, which weighs only 12kg, and parachute trials of Beagle 2 began just recently in October 2002, yet the launch date is fixed for June 2003!

Meanwhile no one doubts that the schedule will be met or that the ambitious mission will be a success. Shortly after Mars Express reaches our neighbouring planet in December 2003, Beagle 2 will be lowered by parachute and then in the sedimentary basin of Isidis Planitia, protected by airbags, it will help to answer the question of whether there has ever been life on Mars.

From page 48 of FLUG REVUE 12/2002

Last updated 4 November 2002

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