Press Release

Mars Express – How to be Fastest to the Red Planet

By SpaceRef Editor
May 30, 2003
Filed under , ,
Mars Express – How to be Fastest to the Red Planet

ESA’s Mars Express is a pioneering mission for several reasons. It is the
first European voyage to Mars, it has been built at much less than the
usual cost, and in record time.


Mars Express is the first example of ESA’s new style of developing
scientific missions: faster, smarter and more cost-effective, but without
compromising reliability and quality – there have been no cuts in tests or
pre-launch preparations. Mars Express will face demanding technical
challenges during its trip to the Red Planet and ESA engineers have worked
hard to make sure it meets them.


"With Mars Express, Europe is building its own expertise in many fields.
This ranges from the development of science experiments and new
technologies – new for European industry – to the control of a mission
that includes landing on another planet. We have never done this before,"
says Rudi Schmidt, Mars Express Project Manager.


Quicker, smarter: safe!


Mars Express’s design and development phase has taken about four years,
compared with about six years for previous similar missions. And its cost,
300 million euros, is much less than other comparable planetary missions.
The "magic" lies in the new managerial approach being used.


This new approach includes the reuse of existing hardware and instruments.
Also, the mission was developed by a smaller ESA team, who gave more
responsibility to industry. Mars Express has been built by a consortium of
24 companies from ESA’s 15 Member States and the United States, led by
Astrium as prime contractor.


However, mission safety was never compromised. "Although we were under
heavy pressure towards the end of the project, we did not drop any of the
planned tests to save time. I call this a fast design phase, followed by
thorough testing activity," says Schmidt.


This new streamlined development method will continue with Venus Express
and probably other future missions.


Launch


Mars Express will be launched on 2 June on board a Soyuz-Fregat rocket
from the Baikonur Cosmodrome in Kazakhstan. The mission consists of an
orbiter and a lander, called Beagle 2. In its launch configuration, Mars
Express is a honeycombed aluminium box that measures 1.5 by 1.8 by 1.4
metres (excluding solar panels), and weighs 1223 kilograms in total. The
Beagle-2 lander travels attached to one side of the spacecraft, folded up
rather like a very large pocket watch. Arrival at Mars is scheduled for
late December this year, when Beagle 2 will land while the orbiter is
entering its orbit around Mars.


The last activities of an intense launch campaign are taking place in
Baikonur at this very moment. Mars Express arrived at the Cosmodrome on 20
March. The spacecraft, fuelled with 457 kilograms of propellant, was
mounted on the Soyuz launcher on 24 May in a process that the Russians
call "marriage". The whole structure was rolled out to the launch pad on
29 May, four days before launch.


The fastest possible trip to Mars


One of the reasons scientists had to develop Mars Express so quickly
arises from the fact that, this summer, Mars and the Earth will be
especially close to each other. Although launch opportunities to go to
Mars occur every 26 months – when the Sun, Earth and Mars form a straight
line – this year the planets will be at their closest, which happens every
15 to 17 years. On top of that, calculations had shown that the best
combination of fuel expenditure and travel time could only be achieved by
launching in the period between 23 May and 21 June. The Mars Express team
had to work very hard to meet this launch window.


As a tribute from one European high-tech organisation to another, Mars
Express is carrying a small container of Ferrari red paint to the Red
Planet.


After the launch


Mars Express will separate from the Soyuz Fregat upper stage 90 minutes
after liftoff. Then the solar arrays will open and the spacecraft will
make contact with ESA’s ground station in New Norcia, Western Australia.


Mars Express will be travelling away from Earth at a speed of 3 kilometres
per second. A crucial operation at this early stage of the trip will be to
release the Beagle-2 launch clamps three days after launch. These clamps
are extra gears to make sure that the lander stays securely attached to
the spacecraft during the launch, but once in space they are not needed
any more. A pyrotechnic device will be activated to release them. This
will be a key step, necessary so that Beagle 2 can be ejected when the
spacecraft arrives at Mars.


Every effort has been made to ensure that things go smoothly. Schmidt
says: "We have tested all aspects of the mission well enough to be
confident that there will be no errors or trivial mistakes. Mars Express
has been developed in record time, but there have been no compromises on
testing, including the ground segment."


Orbiting and landing on Mars


Six days before arrival at Mars, the lander will be released. This
operation is regarded as one of the most complex of the Mars Express
mission. Beagle 2, which weighs only 65 kilograms, is too light to carry a
steering mechanism and is not designed to receive commands during cruise
and landing. So Beagle 2 can only reach its planned landing site by
relying on the orbiter to put it into the correct trajectory and drop it
at a very precise point in space and at a specified speed. The ground
control team at the European Space Operations Centre (ESOC) in Darmstadt,
Germany, will guide this manoeuvre. To be ready for the approach to Mars
and the ejection operations, engineers have been training for months with
simulators that resemble sophisticated computer games. Tests will continue
after Mars Express’s launch.


Approaching Mars, the orbiter will eject the lander and then be left on a
collision course with the planet. In another key manoeuvre, ground
controllers will have to adjust its trajectory, reducing its speed to 1.8
kilometres per second. At that speed, the planet’s gravity will be able to
"capture" the Mars Express orbiter and put it into Mars orbit. Ground
controllers will still have to perform several manoeuvres to get the
spacecraft into its final operational state – a highly elliptical polar
orbit – from where the scientific observations can begin.


In the meantime, Beagle 2 will have landed on Mars. The landing area
covers a large ellipsis, 300 kilometres long and 150 kilometres wide, on
an equatorial region called Isidis Planitia. It was chosen in the light of
the strong Martian winds and the relatively smooth surface of the site.
The lander will deploy parachutes, and then large gas-filled bags will
protect it as it bounces to a halt on the surface. Once landed, Beagle 2
will emit a "beep", a signal that will tell operators at the United
Kingdom’s Jodrell Bank radio telescope station that it has touched down
safely. This 9-note call sign was composed for the Beagle-2 team by the
British pop group, Blur.


Mars Express will investigate the Martian surface, subsurface, and
atmosphere for at least two years. The lander will operate on the surface
for about six Earth months, relaying its data to Earth through the
orbiter.


Mars Express will help answer fundamental questions about Mars, such as
the presence and quantity of water, and possible signs of present or past
life. In the worldwide effort to explore the Red Planet in recent years,
the European Mars Express mission represents the most thorough
investigation of Mars attempted so far.



For further information please contact:


ESA – Communication Department
Media Relations Office
Tel: +33(0)1.53.69.7155
Fax: +33(0)1.53.69.7690

For more information about the Mars Express mission and launch campaign
visit:
http://www.esa.int/marsexpresslaunch


Live images of the Mars Express spacecraft are available at:
http://sci2.esa.int/spacecam/marsexpress.htm


For more information about the ESA science programme, visit:
http://sci.esa.int


For more information about ESA visit:
http://www.esa.int


SpaceRef staff editor.