Saturday, July 01, 2006
A mysterious shiny coating found on rocks in many of Earth's arid environments could reveal whether there was once life on Mars, according to new research.
The research, published in the July edition of the journal Geology, reveals that the dark coating known as desert varnish creates a record of life around it, by binding traces of DNA, amino acids and other organic compounds to desert rocks. Samples of Martian desert varnish could therefore show whether there has been life on Mars at any stage over the last 4.5 billion years.
The researchers hope that these results will encourage any future Mars Sample Return mission to add desert varnish to its Martian shopping list.
The source of the varnish, which looks like it has been painted onto the rocks, has intrigued scientists since the mid nineteenth century, including Darwin, who was so fascinated that he asked the geochemist Berzelius to investigate it.
Released by the Imperial College London on June 30th 2006. Further information can be obtained via the email link given at the bottom of the page.