Discoveries about life on Earth inspire Beagle 2
14 December 2000
The nineteenth century spirit of discovery is inspiring the effort to land the first probe on Mars in the twenty first century. Last week, as if to give the inspiration a boost, the largely-British team building the Beagle 2 lander for Mars Express held the second meeting for 'adjunct' scientists in one of the finest nineteenth century monuments to discoveries about life on Earth - the Natural History Museum in London.Beagle 2 is named after the ship in which the illustrious nineteenth century scientist, Charles Darwin sailed when he developed his ideas about evolution and made some of mankind's most significant discoveries about life on Earth. The tiny probe's quest is to find evidence for past or present life on Mars and so make similarly significant discoveries about the possibility of life beyond Earth. No other mission to Mars planned for at least the next decade has exobiology so central to its mission.
Almost within sight of the giant skeleton of Diplodocus in the Natural History Museum's august entrance hall, the discussion turned to the experiments on board Beagle 2, the environment on Mars, and the chance of finding evidence for past and present life.
As Earth and Mars experienced similar early histories, the chances of primitive life (though nothing so advanced as Diplodocus) on early Mars are good, said Andri Brack from the Centre de Biophysique Moleculaire, France and chairman of the adjunct scientists group. Beagle 2 will fulfil all the requirements necessary to search for life: it will land in a sedminetary region where fossils could have been preserved, examine sub-surface samples protected from oxidation at the surface, measure the isotopic ratio of organics and minerals, look for visual and chemical evidence of water, and generally monitor the local environment.
All these tasks must be accomplished in just 180 sols (Martian days which are almost the same length as an Earth day). The first few days will be spent running pre-programmed sequences, imaging the site and running the environmental sensors, Mark Sims, Beagle 2 project manager from Leicester University told the meeting. Only after about a month will the lander be ready to start doing detailed rock and soil analysis. "It'll take quite a bit of time before we're ready to pick up the first rock, but sometimes slow operations are good operations," said Sims.
Any space probe that lands on another solar system body has to meet standards of cleanliness laid down in international law. In Beagle 2's case this is 300 000 spores in total, Judith Pillinger from the Open University said. The plan is to use 'clean' manufacturing methods, sterilisation of some parts and cleaning protocols that will get rid of dead spores as well as live ones. "We don't want to scupper our experiments by taking our own life there, dead or alive," says Pillinger. Beagle 2 will use various levels of protection to maintain its cleanliness including the heat shield to protect the lander when it travels through the Martian atmosphere and internal bioshields and bioseals.
The adjunct scientists are a gathering of people interested in the science Beagle 2 will do, but with no formal status on the project. "The group is open to all comers," Colin Pillinger, Beagle 2 Consortium Leader from the Open University said in a plea for more members, especially from Europe. "We want to increase the pool from which the instruments providers can recruit collaborators," he said. The frequency of meetings is expected to increase in the run up to launch in June 2003.
For further information on the adjunct scientists' group contact Andri Brack e-mail: brack
cnrs-orleans.fr
