BY DR EMILY BALDWIN
Posted: 23 June, 2009
An illustration of a dust storm on Mars. New research suggests that intense dust storms could create electrical discharges. Image: Brian Grimm and Nilton Renno.
After reviewing the strength, duration and frequency of the non-thermal activity, as well as the possibility of other sources, the scientists arrived at the conclusion that the dust storm most likely caused dry lightning. The work confirms soil measurements from the Viking landers 30 years ago that suggested that dust storms might be electrically active like Earth’s thunderstorms and therefore might be a source of reactive chemistry, but at the time the theory was untestable.
In 2006, theoretical modelling, laboratory experiments and field studies on Earth led to the conclusion that there was no direct evidence that lightning occurred on Mars. The new research clearly challenges those findings and has significant implications for Mars science.
"It affects atmospheric chemistry, habitability and preparations for human exploration. It might even have implications for the origin of life, as suggested by experiments in the 1950s," says Nilton Renno, a professor in the Department of Atmospheric, Oceanic and Space Sciences.
"Mars continues to amaze us," adds Michael Sanders of the Jet Propulsion Laboratory. "Every new look at the planet gives us new insights."
The new findings will be published in a forthcoming issue of Geophysical Research Letters.