Finding Mars between the cracks

Scotsman.com ^ | 3/19/04 | Jim Gilchrist

[LibWhacker]

JIM GILCHRIST

Charles Cockell opens a growth chamber, tucked away within the Cambridge headquarters of the British Antarctic Survey, to expose rows of Petri dishes. He picks one of them up, its interior slicked with tell-tale green.

"These are going into space," he says, matter-of-factly.

In the corridor outside hangs a stuffed albatross, a trophy from some bygone Antarctic expedition, but the still-living life forms in the Petri dishes have been gleaned on much more recent trips, and not just to Antarctica. These are photosynthetic cyanobacteria - "extremophiles" as they’re known - some from the Antarctic, but others collected in the Negev Desert or, perhaps most appropriately, in the Haughton Crater in Arctic Canada, where they grow in the impact fissures of rock shattered some 23 million years ago when a comet or meteorite slammed into the Earth.

Some scientists believe the seeds of life may have come to Earth riding on such a projectile: now these humble but resilient micro-organisms, in this case the samples from the Negev, will themselves be dispatched into space to see whether they could survive a journey between worlds.

Cockell, an astrobiologist so committed to space exploration that he once stood in a general election on a "Forward to Mars" ticket, is waiting for the resumption of NASA’s space shuttle programme, in abeyance since the Columbia disaster of a year ago but expected to resume in March or April next year. The bacteria will be freeze-dried on to glass discs and kept outside the International Space Station as part of a European Space Agency experiment. "We’ll be looking at the possibility of transfer of organisms from one planet to another, at whether they can survive extreme ultra-violet radiation, extreme cold and vacuum."

Over the past two or three decades, the discovery of extremophiles, organisms which can thrive in conditions which would be intolerable to other life, has re-written the rule book as regards where life can and cannot exist. To astrobiologists such as Cockell, working in the interface between biological and space sciences, the presence of extremophiles in environments as hostile as desert rock, polar ice, boiling sulphurous pools and volcanic vents deep in the ocean has significantly changed thinking on the likelihood of life elsewhere in the universe.

"I suppose the most profound impact is that they expand the known boundaries of life," he agrees. "It’s made us realise there are probably a large number of habitats on different planets which can potentially support life, from the sub-surface of Mars to the oceans of Europa."

Cockell visits the Antarctic with the BAS but also regularly heads towards the other Pole, into Canada’s high Arctic, to don a spacesuit at a simulated Mars base amid the bleak rockscape of the Haughton Crater. A manned mission to Mars may seem far off, but he is among those paving the way. And with the recent spate of data and images from Mars, the publicity surrounding Britain’s sadly silent Beagle Mars probe and President Bush’s pledge that America will send a manned mission there by 2030, Mars has never been more in the public eye. Cockell believes there is "a reasonable chance" that there may be at least microscopic life on Mars, "given that we know that rocks can be transferred between Mars and Earth. Whether rocks ever made it to Mars carrying life from Earth, and whether it would have successfully transferred to Mars, is really unknown".

Hence his interest in the inhabitants of the Petri dishes. Some have already been subjected to simulated space conditions, frozen in a vacuum. "They’ve been on a simulated meteorite trip into space," he says, "and they came back alive."

But while dispatching his microscopic charges into space, he believes that we should be following after. "Man is an exploring animal," he wrote in a letter to the Times last year, forcibly putting the case for manned space missions. Certainly, Cockell’s own CV backs up his claim: now 36, apart from his migrations due south with the BAS, he led the first western expedition into post-communist Mongolia, and flew a specially developed moth-gathering microlight on an environmental study of the Indonesian rainforest, ultimately crashing it into a tree. "It was fun, though," he recalls, "and we also caught about 10,000 moths."

He is a Fellow of the Explorers Club of New York but also, rather more intriguingly, is about to stand down as founding president of the Association of Mars Explorers, when it holds its annual dinner in San Jose, California, at the end of this month.

Like other members of "the Mars Club", as it is known, Cockell may not have actually set foot on the inhospitable planet, but he has worked in the Mars-analogue environment of the NASA Haughton-Mars base on Canada’s Devon Island. Haughton, a 24km-diameter impact crater, is a desolate waste, with environmental and geological conditions which can at least partly simulate conditions on Mars.

Whether rocks ever made it to Mars carrying life from Earth is really unknown

Among agencies and organisations which have made use of its unique facilities is the Mars Institute, a scientifically grounded organisation of which Cockell is a board member.

In some exercises at Haughton, Cockell and his colleagues don spacesuits for simulated "Mars treks". "It’s interesting and quite uncomfortable," he says, "but it does give you a feel for what it would be like to do field work on Mars."

Impact craters such as Haughton also provide insight into his particular speciality - extremophiles, which can flourish within the impact-fragmented rocks - but also give insights into the possible evolution of Mars in terms of its water history. Haughton once contained a crater lake which would have been colonised by the kind of micro-organisms which may yet be found on a Mars now known to have had surface water in the past.

With a view to the artificial "greening" of Mars which some argue could ultimately render the planet humanly habitable, Cockell has subjected cockroaches and other insects to the kind of ultra-low pressures which might be experienced in the early stages of terraforming Mars, and found they survived at surprisingly low pressures.

However, perhaps his most unorthodox venture in the cause of interplanetary exploration was during the General Election of 1996, when he stood against John Major, then Prime Minister, in his Huntingdon constituency, on behalf of the Forward to Mars Party. He took 91 votes. It was prompted by his disgust at the government’s lack of commitment to space exploration - the party slogan was "Time for a change: a change of planet" - but, he says, he found listening to the public’s views on space travel invaluable. "I got to speak to Major on election night. He was very much in favour of what the European Space Agency was doing, but not very keen on getting involved in discussion about what Britain might do."

But does he hope ever to tread the Red Planet in reality? "I think that’s less and less likely. By the time there’s a mission I’ll be too old," he replies. "But I hope I might at least see it happen within my lifetime. In many ways that’s what the Association of Mars Explorers is about; for those who can’t go there at the moment, but want to plan for the day."