Revealing the Red Planet

Next June, Leicester University will embark on a mission to Mars - via the Beagle II lander, which it helped to design. Geoff Watts reports.

From December next year, if all goes well, a small patch of the surface of Mars will be for ever Leicester. That month will see the Beagle II lander, part-designed at Leicester, descending to the Red Planet in preparation for the latest attempt to answer a question that has been fascinating space buffs for decades: is there now or (more likely) has there ever been life on Mars?

It seems therefore apt that Leicester should be the launchpad for this year's British Association Festival of Science, which begins next Monday. The festival will cover everything from science cinema to wildlife crime and, fittingly, there is a section on "Space - the new frontier", which includes a session on how to be a rocket scientist and a debate about whether the UK should participate in the European Space Agency's manned space programme.

Although the UK has historically decided to play no part in manned activities, Leicester is among a group of universities at the forefront of ESA programmes such as Beagle II. The lander, usually described as resembling a metre-wide pocket watch, will be carried to its destination by the ESA's Mars Express, due to be launched next June. Once the Beagle II has been parachuted into place, it will open up to deploy four solar panels with which to charge its batteries. And when fully powered it will extend its Paw - the appropriately canine acronym for its position adjustable workbench.

The Paw - a platform sitting at the end of a 70cm robotic arm and carrying all Beagle's instruments - was designed and built at Leicester's Space Research Centre. So too was one of the instruments, an X-ray spectrophotometer for studying the elemental composition of Martian rocks and soil. But the biggest challenge was Leicester's key task: integrating and assembling the Paw's instrument package.

"Organised chaos" is how the centre's Mark Simms laughingly describes the process. But although the instruments were made separately by various commercial and academic organisations in Britain and elsewhere in Europe, the scientists involved have avoided the personal or institutional clashes that can easily subvert any international collaboration. "The team members don't think of themselves as belonging to separate groups," Simms says. "They think of themselves just as Beagle II. As a single virtual organisation with clear lines of authority. And if there is a problem, everyone mucks in to solve it."

According to Alan Wells, director of the Space Research Centre, Leicester has the UK's largest campus-based space science group. Its history can be traced back to the early 1960s, to a young postdoctorate called Ken £who was studying X-ray emissions from the Sun. His camera (a bit like a Kodak box Brownie, but with X-ray film) needed calibration. Leicester had the facilities. £came to use them and decided to stay. He is now the about-to-retire head of Leicester's department of physics and astronomy.

Initially in collaboration with University College London, £built a reputation for X-ray astronomy at Leicester. In the 1970s, the university decided to back a substantial programme of space-system technology and engineering. Alan Wells was appointed to handle it; he has overseen the subsequent growth from 20 people to about 60. Although also due for retirement this September, he is staying on for another year - so it is on his watch that the Beagle II launch will take place.

The instruments mounted on Beagle II's Paw - they include three spectrometers, a microscope, two cameras, and a corer-grinder for taking rock samples - weigh just 8.7kg - a remarkable feat of miniaturisation. "A lot of lateral thought went into it," Simms says. "If a component could be made to do two jobs, it was."

Although itself immobile, Beagle II will carry a mole: a self-burying device on the end of a tether by which it is powered and controlled. The mole will hammer itself into the soil, collect samples down to a depth of 1.5m, then go into reverse and hammer its way back up.

The search for extinct life relies on an idea developed by Colin Pillinger of the Open University. His instruments on the Paw will be looking for an isotope of carbon (C13) in rock samples. Biologically produced carbon compounds contain different proportions of C13 from those formed geologically. But the technique requires material that hasn't been exposed for long periods to the Martian atmosphere. Hence the need for an instrument to cut cores out of the inside of rocks, and for the mole to take samples from well below the surface.

Beagle II will spend its first ten days on Mars mapping the locality. Only then will the sample collecting begin. Each complete cycle - going to a rock, cutting a core, bringing it back and analysing it - will take six or seven days.

The actual conduct of the experiments is anything but exciting, Simms says. "It is like watching paint dry. The control of Beagle II is not done in real time. You send instructions, then get a reply half a day or two days later depending on where Mars Express is with respect to Beagle.

"We should be able to get most of the science done in 60 to 70 days, but you have to allow for things to go wrong. The mission is funded to last 180 days on the surface. Hopefully it'll last longer than that, but there are no guarantees. From the second it lands it is dying. Its electronics are being subjected to vast temperature excursions. Its solar panels are getting covered with dust."

Some of the Beagle II operations will be run from Leicester's National Space Centre. This visitor attraction, supported by the Millennium Commission and backed by the university, the city council and local commerce, opened in June last year. It aims to foster a wider public interest in space research, and Leicester University has contributed much to its development. If visitor numbers are anything to go by, the centre is proving to be a success.

As a joint author of the original proposal, Wells is delighted. "We had a target of 300,000 visitors in the first year. In fact, we hit that figure six weeks early. We've also had visits from 1,800 schools. That is a lot of young people."

Although the National Space Centre helps draw public attention to Leicester's interest in space science, the university's reputation rests principally on Beagle II and its many other research interests. Earth observation satellites, for example. The more conscious we become of ourselves as a global community, and the more we maltreat our shared environment, the greater will be the demand for data of the kind best acquired by satellite images and measurements.

John Remedios is a lecturer in earth observation science. He and his colleagues are involved in several major projects, including a scheme for the accurate measurement of the surface temperature of the sea - important in the analysis of global warming - and the study of ozone depletion and the transport of atmospheric pollutants. "We use space observation to give us data on any aspect of the Earth and its climate," Remedios says.

Much of Leicester's research is purely academic - the Swift project, for example. This, says Wells, is studying the brief bursts of gamma rays that reach us from distant space. "The theorists have had a wonderful time trying to explain them, with very little data to constrain their imaginations. The bursts are difficult to pin down because they only last from a fraction of a second up to ten seconds."

A few years ago it was discovered that each short-lived gamma-ray burst is followed by an afterglow of X-rays. These offer sufficient time to locate an event precisely and point an optical telescope at it. It has been possible to associate some of these events with particular galaxies, calculate their distance, and hence work out how much energy is being liberated. The events giving rise to these bursts turn out to be among the most violent in the universe.

Leicester has joined with Nasa Goddard Space Center and Penn State University to devise systems for locating a gamma-ray burst and training an X-ray telescope on it within 100 seconds. Leicester staff built some of the key elements of the telescope.

But not all the centre's joint programmes with industry are space-related. Some X-ray detection equipment developed for use in satellites has been adapted for tracking radio-labelled anti-cancer drugs.

For all the diversity of interest, however, it remains Leicester's involvement with Beagle II and the question of life on Mars that catches the public imagination. Simms knows that the mission may not yield any clear answers. For one thing, he points out, it is difficult to prove a negative. And then, more cheerfully, adds a further thought. "Of course, any positive indication would mean you would want to go back with even more sophisticated instruments."

The British Association Festival of Science runs from September 9-13 at the University of Leicester.