Dorset area that replicates early Mars to help future probes discover life
Image credit: pa
An area of Dorset which mimics the conditions of early Mars could give scientists clues about where to look for life on the Red Planet in future missions.
The county’s St Oswald’s Bay is home to highly acidic sulphur streams that host bacteria that thrive in extreme conditions.
Now scientists at Imperial College, London, believe they have found ancient traces of fatty acids - key building blocks of biological cells – in these acidic streams.
Because the environment is so similar to that of Mars during its middle-ages, the findings hint that life might once have existed on the planet. When small organisms die, they leave a biological footprint in the form of fatty acids (the building blocks of cells) preserved in rock. By applying their findings to Mars, the scientists concluded that there could be the equivalent of nearly 12,000 Olympic sized pools of organic matter on the planet representing traces of past life.
Researcher Jonathan Tan, from Imperial College London, said: “St Oswald’s Bay is a present-day microcosm of middle-aged Mars. As the acid streams dry up, like during Mars’ ‘drying period’, they leave geothite minerals behind which preserve fatty acids that act as biological signatures.”
The iron-rich mineral goethite turns to hematite which is very common on Mars and gives the planet its red colour. Examining rock deposits around St Oswald’s Bay, the scientists found goethite hosting many microbes as well as traces of their fossilised organic remains.
Professor Mark Sephton, head of Imperial’s Department of Earth Science & Engineering, said: “Mars harboured water billions of years ago, meaning some form of life might have thrived there."
“If life existed before the water dried up, it would probably have left remains that are preserved to this day in Martian rock.”
Previous missions to find life on Mars have used heat to look for microbial remains in rock. Scientists suspect the heat might have caused minerals to react with and destroy any organic matter, possibly explaining why we have not yet identified traces of life. However, heating goethite or haematite does not destroy organic matter, meaning scientists are more likely to find remnants of life, if they exist.
Nasa’s latest Mars probe launched earlier this month with a mission to discover more information about the internal workings of the red planet.