It just carries on working: The German HRSC onboard Mars Expressnow in its third year (Forwarded)

Deutsches Zentrum für Luft- und Raumfahrt (DLR)
Koeln, Germany

Contact:

Elke Heinemann
German Aerospace Center (DLR)
Corporate Communications, Online Communication - DLR Web Portal
Tel.: +49 2203 601-2867
Fax: +49 2203 601-3249

Prof.Dr. Ralf Jaumann
German Aerospace Center
Institute of Planetary Research, Planetary Geology
Tel.: +49 30 67055-400
Fax: +49 30 67055-402

Ulrich Köhler
Institute of Planetary Research
Tel.: +49 30 67055-215
Mobile: +49 175 1641737
Fax: +49 30 67055-402

10 January 2007

It just carries on working: The German HRSC onboard Mars Express now in
its third year

Exactly three years ago today, the High Resolution Stereo Camera (HRSC)
onboard the Mars Express probe captured its first image data of our
neighbouring planet. After more than 3800 orbits of Mars, the camera has
imaged an area larger than North and South America with a resolution of
between ten and twenty metres per pixel, in colour and in 3D. The camera
experiment onboard the European Space Agency's (ESA) first planetary probe
is being managed by the German Aerospace Center (DLR). The Freie
Universität Berlin (FUB) is playing the leading scientific role in the
HRSC.

"The instrument is still working perfectly after nearly 4000 orbits of
Mars," commented the delighted Ralf Jaumann, experiment manager from the
DLR Institute for Planetary Research in Berlin-Aldershof, about the
reliability of the HRSC, "and there's no reason why the HRSC shouldn't
provide us with many more years of service." The scientific leader of the
HRSC experiment, the Principal Investigator (PI), Gerhard Neukum, from the
FUB, is also confident that the defined objectives can be achieved, at
least by the end of this year. "We will have mapped over fifty percent of
Mars in very high resolution, in colour and, most excitingly, in 3D
format," explains the scientist.

"Having said that, together with the leaders of the other six experiments
on Mars Express we are striving to obtain a second extension to this
mission: We want to record as much of the surface as possible in the
Hirsch's maximum resolution of ten to twenty metres per pixel." ESA will
come to a decision on a further extension of Mars Express at the end of
February.

The complex image data from DLR and FUB will be integrated onto a global
3D image map in one of the DLR-sponsored special projects from 2007. Over
the next few years, this will give Mars scientists from all over the world
access to what we call "digital terrain models": The HRSC will generate a
topographical collection of data from the surface of Mars of a quality
which has never been seen before. Pictures taken by the stereo camera in
resolutions from ten to a hundred metres per pixel cover approximately two
thirds of the surface of Mars. The objective of this camera experiment is
to record images of half of the planet in a resolution of 10-20 metres per
pixel in 3D and in colour by the provisional end of the Mars Express
mission on 31 October 2007.

The camera, built and developed at DLR by a team led by the Principal
Investigator in cooperation with German industry partners, scans strips of
terrain on the surface of Mars using nine banks of light-sensitive sensors
set at right-angles to the direction of flight. These strips, which are
imaged at different angles of view and through four colour filters, are
many hundreds of kilometres in length. As expected, the HRSC painlessly
came through a phase for the second time at the end of 2006 when Mars
disappeared behind the Sun and the camera remained switched off for
several weeks for safety reasons. The HRSC project is currently the most
comprehensive German experiment to be involved on a planetary mission.

The HRSC had already taken its first image strips of some 700 kilometres
in length on 10 January 2004 during Mars Express' tenth orbit. This took
place while the orbit was being fine-tuned by staff at the ESA mission
control centre in Darmstadt. A few hours later, these digital image
signals reached the HRSC Experiment Team in the DLR Institute for
Planetary Research in Berlin, for the first time making it possible to
identify details of the Mars landscape on the monitor amid enthusiastic
response from the scientists and engineers involved.

"Even today, in routine operations, we are discovering ever more
fantastic, but above all highly interesting, details from a scientific
point of view," says a delighted Gerhard Neukum. In three years, the HRSC
has recorded 45 million square kilometres in a resolution of between ten
and twenty metres per pixel. That represents 31% coverage of the 145
million square kilometres of Mars's surface, which is approximately the
same size as all of Earth's continents put together. About 80 million
square kilometres were recorded at a resolution of more than 40 metres per
pixel (54.4%): That represents roughly an area eight times the size of
Europe. In total, 68% or almost 100 million square kilometres was covered.
Experiment manager Ralf Jaumann added: "With a length of 4000 kilometres,
we have created the largest recorded image in the Solar System!"

In this process, approximately 1.5 terabytes of compressed data from Mars
Express were sent back to Earth. The HRSC Experiment Team in Berlin
Adlershof decompresses and calibrates these packages of raw data and tests
them for minor data errors. The Experiment Team then converts all data
into geometric image mapping projections. Then, so-called "digital terrain
models" are generated by combining different HRSC channels, where the
third dimension becomes visible and altitude measurements can be prepared
in the image data. The different data products will be made available to
all scientists through ESA and NASA data archives after about six months.

Mars Express took six months to cover the 55 million kilometres, which
separate Earth from our neighbouring planet and arrived on 25 December
2003. Originally, the mission was planned to last only one Mars year,
which is the equivalent of two Earth years. The huge scientific success of
the mission prompted the ESA to prolong it, initially through 2006 and
2007.

As well as Mars Express there are also the two NASA probes Mars Odyssey
(arrival at Mars on 24 October 2001) and Mars Reconnaissance Orbiter
(arrival 10 March 2006) currently actively engaged in orbit around Mars.
Only recently, NASA lost all contact with the Orbiter Mars Global
Surveyor, a ten-year old, extremely successful "Mars veteran". Spirit and
Opportunity, two NASA Rovers have been roaming slowly over the arid
surface of Mars since January 2004, almost as long as Mars Express. None
of these Mars missions are competing with each other and area instead
mutually complementary within the framework of a worldwide Mars
Exploration programme. In this context, the Hirsch's 3D image data is
forming the basis of a topographical map covering the whole of Mars.

These HRSC images have provided the answers to numerous scientific
questions: The 45 strong HRSC science team was able to identify traces
left behind by glaciers, water courses and surface water million or even
billions of years ago on today's arid surface, and clarify when and where
water and ice formed the surface of Mars -- mainly in the early part of
the planet's four and a half billion year history.

The topographical image maps will also be used to select future landing
zones for unmanned Mars probes. Within the framework of its Aurora
programme at the start of the new decade, ESA is planning intensive
exploration of Earth's moon and in particular Mars in the ExoMars project
which is being hailed as a "Flagship mission" to our neighbouring planet.

Amongst other things, ExoMars will be attempting to provide insights to
still unanswered questions concerning the existence of past or even
present life on Mars by using a Rover vehicle capable of covering wide
areas of terrain. DLR will be collaborating with different scientific
contributions and technical developments on ExoMars and the team from the
Freie Universität Berlin will also be making their own scientific
contribution.

The HRSC camera experiment on the European Space Agency Mars Express
mission is led by Principal Investigator (PI), Professor Gerhard Neukum,
(Freie Universität Berlin), who was also responsible for designing the
high-resolution stereo camera. The science team comprises 45
co-investigators from 32 institutes and ten nations. The camera was
developed at the German Aerospace Center (DLR) led by PI G. Neukum and
built in cooperation with industrial partners (EADS Astrium, Lewicki
Microelectronic GmbH and Jena-Optronik GmbH). It is operated from the DLR
Institute of Planetary Research in Berlin-Adlershof in conjunction with
ESA/ESOC. The systematic processing of the HRSC data takes place at DLR.
The illustrations shown here were generated by the PI group at the
Institute of Geological Science at the Freie Universität Berlin in
conjunction with the DLR Institute of Planetary Research.

Related articles

* HRSC - the High Resolution Stereo Camera
http://www.dlr.de/mars/en/desktopdef...944_read-1409/

Related links

* DLR Mars Express Special
http://www.dlr.de/mars
* DLR Institute of Planetary Research / HRSC
http://solarsystem.dlr.de/Missions/express/
* DLR Reg. Planetary Image Facility (RPIF)
http://solarsystem.dlr.de/RPIF/bestand.shtml
* FU Berlin, Inst. for Geosciences
http://www.geoinf.fu-berlin.de/eng/p...mars/index.php
* ESA Portal / Mars Express and HRSC
http://www.esa.int/SPECIALS/Mars_Express/

IMAGES:

* An ice-filled crater at Mars' north pole

http://www.dlr.de/en/DesktopDefault....-Image.1.2770/

* HRSC - the High Resolution Stereo Camera

http://www.dlr.de/en/DesktopDefault....d-Image.8.478/

* Ice and dust layers

http://www.dlr.de/en/DesktopDefault....-Image.1.2771/

* Three years of Martian mapping with HRSC

http://www.dlr.de/en/DesktopDefault....-Image.1.2772/