An article in New Scientist suggests that our search for life on Mars may have missed something…

A paper by Rafael Navarro-Gonzalez of the University of Mexico and others demonstrates that the GCMS (gas-chromatograph mass spectrometer)  instrument was incapable of detecting organic compounds even in Mars-like soils from various locations on Earth. This includes Chile’s Atacama desert, where other tests prove that living microbes are indeed present.

In some soils – including samples taken from Rio Tinto in Spain, which contain iron compounds similar to those detected in Mars soils by NASA’s rover Opportunity, the sensitivity of the GCMS was actually a million times lower than its claimed threshold for detection.

So, basically what this means is that if some alien race used NASA-like technology to probe parts of Earth,  they too would have gone home empty handed.  Hmmmmm.  Maybe that’s just as well.