NASA's Viking missions to Mars in the 1970s showed the Martian soil to be disappointingly lifeless and depleted in organic materials, the chemical precursors necessary for life. Last year, in the driest part of Chile's Atacama Desert, the
research team conducted microbe-hunting experiments similar to Viking's
, and no evidence of life was found. The
scientists called the finding "highly unusual" in an environment exposed to the atmosphere... The Atacama appears
to be the only place on Earth Viking would have found no trace of life.
--SONO Wasa. com
Which of these weather phenomena is responsible for the findings in the excerpt?
O La Nina
O El Nino
O Position on the Continent
Orographic Effect (Rain-Shadow)