It would appear that the US President has been briefed by Phoenix scientists about the discovery of something more 'provocative' than the discovery of water existing on the Martian surface. This news comes just as the Thermal and Evolved Gas Analyzer (TEGA) confirmed experimental evidence for the existence of water in the Mars regolith on Thursday."

Asked to speculate yesterday on what it may have now found, Dr Clarke said the instrument was designed, among other things, to spot dissolved ammonium and nitrate salts.

"On Earth, if you have a lot of ammonium and nitrate it usually means there is organic activity. We excrete it as waste and other organisms use it."

High volumes of such chemistry in a river could point to effluent run-off from a farm. While not life itself, "it could be a sign of biology