Wednesday, September 26, 2007

Beagle 2

Credit: ESA

Back to our history...

Launched with Mars Express was Beagle 2, a lander that was developed separately from Mars Express, which was a project of the European Space Agency (ESA). Beagle 2 was conceived by a group of British academics headed by Professor Colin Pillinger of the Open University, in collaboration with the University of Leicester. The spacecraft's purpose was to search for signs of Martian life, past or present, and its name reflected this goal, as Professor Pillinger explained:

HMS Beagle was the ship that took Darwin on his voyage around the world in the 1830s and led to our knowledge about life on Earth making a real quantum leap. We hope Beagle 2 will do the same thing for life on Mars.

A point at 10.6° North, 270° West in Isidis Planitia, a large flat sedimentary basin that overlies the boundary between the ancient highlands and the northern plains of Mars, was chosen as the landing site. The lander was expected to operate for about 180 days and an extended mission of up to one Martian year (687 Earth days) was thought possible. The Beagle 2 lander objectives were to characterize the landing site geology, mineralogy, geochemistry and oxidation state, the physical properties of the atmosphere and surface layers, collect data on Martian meteorology and climatology, and search for possible signatures of life.

Promotion for Beagle 2 was somewhat unusual for your typical mission to Mars. In an effort to publicize the project and gain financial support, the designers sought and received the endorsement and participation of British artists. The mission's call-sign was composed by the band Blur, and the "test card" (Calibration Target Plate) intended for calibrating Beagle 2's cameras and spectrometers after landing was painted by Damien Hirst.

Beagle 2's instruments included a robotic arm known as the Payload Adjustable Workbench (PAW), designed to be extended after landing. The PAW contained a pair of stereo cameras, a microscope (with a 6 micrometer resolution), a Mössbauer spectrometer, an X-ray spectrometer, a drill for collecting rock samples, and a spotlamp. In addition, a Rock Corer/Grinder could collect a core sample from inside any rocks within reach of the robot arm. Rock samples were to be passed by the PAW into a mass spectrometer and gas chromatograph in the body of the lander, called the Gas Analysis Package (GAP). This instrument was to measure the relative proportions of different isotopes of carbon. Since carbon is thought to be the basis of all life, these readings could have revealed whether the samples contained the remnants of living organisms.

In addition, Beagle 2 was equipped with a small "mole" (Planetary Undersurface Tool, or PLUTO), to be deployed by the arm. PLUTO had a compressed spring mechanism designed to enable it to move across the surface at a rate of about 1 cm every 5 seconds, and to burrow into the ground and collect a subsurface sample in a cavity in its tip. The mole was attached to the lander by a power cable about three meters long, which could be used as a winch to bring the sample back to the lander.

The above photo is of the back side of Beagle 2, slowly drifting away from Mars Express. This image, taken December 19, 2003, shows the lander when it was about 20 meters away from Mars Express, on its way to Mars.

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