Life on Mars

Materials World magazine
,
1 Sep 2012

NASA’s latest space rover has successfully landed on Mars, but how close are we to discovering life on the red planet? A clue may lie much closer to home – on a remote Scottish hillside, no less.

So after years of meticulous planning, a multi-billion dollar budget, the best people in their respective fields collaborating to achieve personal and team targets some called impossible, amazing images that captivated the world and a general feeling of ‘what next?’, an incredible journey finally came to an end earlier this month. No, not the London Olympics, but the NASA Mars Science Laboratory rover Curiosity, which touched down on the red planet on 6 August.

It might look like something I used to bolt together with my Meccano number 5 set (although I think the plutonium-238 radioisotope thermo-electric generator only came with the number 10 set), but it is the suite of cameras on Curiosity that is really impressive, including the Hand Lens Imager for extreme close-up pictures of rocks, soil and the holy grail of Martian exploration – ice. It also has an eye-level high-resolution stereo mast camera, for wide-angle shots and inspecting material collected by the robotic arm. And, for the first time, the rover incorporated a camera to capture high-definition colour video footage of the actual descent. These cameras might be state-of-the-art, but what struck me about the first images beamed back was just how ordinary and Earth-like the planet’s surface appeared – it could be any dusty corner of the American mid-west.

It isn’t, of course, and during its two-year mission Curiosity will analyse dozens of samples scooped from the surface or drilled from just below it. The hope is that such analysis will reveal whether conditions have been favourable for microbial life and if there is evidence of possible past life. Previous missions have proven the existence of water on Mars (albeit no longer in liquid form), and water is a crucial component for life. According to Dr Robert Zubrin, founder of the Mars Society, if life is a natural, chemical development wherever liquid water, reasonable temperatures and various minerals occur, then why shouldn’t there be evidence of it on Mars?

If so, this would have profound implications on the probability of life elsewhere in the universe. As Dr Zubrin says, ‘If life can develop wherever it has a decent planet, it means that the universe is filled with life. And if life is everywhere, it means intelligence is everywhere. It means we’re living in an inhabited universe.’

One small clue to such an outcome may already be apparent – and much closer to home. The mineral macaulayite is believed to exist only in a quarry at the foot of Bennachie, a small but distinctive range of hills in Aberdeenshire, UK. According to a report by BBC Scotland, some Mars scientists believe it could be the same mineral that gives the planet its red colour. Macaulayite occurs as a secondary mineral formed in deeply weathered granite in the presence of water, so if it is found on Mars, it provides further proof of water existing at some time in the planet’s history. The mineral was discovered in the seventies in an outcrop of reddened, deeply weathered granite, and a detailed description was published in Mineralogical Magazine in March 1984, by researchers from Aberdeen’s Macaulay Institute led by mineralogist Jeff Wilson.

Apart from a few dedicated mineralogists, Bennachie is better known for its more ancient history – neolithic standing stones, Bronze Age settlements, Iron Age hill-top forts, and possibly the site of the Battle of Mons Graupius between the Romans and Picts more than 2,000 years ago. If its connection to Mars is proven, it would provide a wonderful link between this mysterious past and the truly Olympic effort by the NASA team.