14 DAY TRIAL // One of the most peculiar occurrences in nature is the fact that deserts can experience lightning. This should not happen, experts say, as the amount of precipitations in some of the world's driest areas is almost negligible. However, dust storms appear perfectly capable of producing lightning discharges, a fact that would seem to suggest that dust particles can take on electrical charge. Usually, this material is neutral, and so experts have been trying to determine how is it exactly that it becomes charged for many years, Nature News reports.
The fact that some neutral particles are perfectly capable of gaining a net electrical charge has been a phenomenon physicists have been familiar with for centuries. Experts say that this is one of the main reasons why factories such as sugar refineries, or even facilities that process coal, sometimes blow up unexpectedly. A segment of the international scientific community has always argued that a gradual build-up of static electricity may be responsible for this type of occurrences, but this explanation never fully accounted for all the factors involved in the process.
Now, physicist Troy Shinbrot, from the Piscataway, New Jersey-based Rutgers University, proposes a new theory on how electricity appears in dust storms. He says that the static energy explanation never really satisfied him, given the fact that sand and dust are usually incapable of conducting electricity. So he set out to discover the events that eventually lead to these materials producing a large enough electrical field to allow for the formation of massive lightning bolts, similar to the ones in thunderstorms. “These materials are insulators under very dry conditions, so where are the charges coming from?” he asked before beginning the investigation.
Shinbrot's own idea didn't make sense to the expert himself. However, much to his amazement, the idea he developed held up in theoretical and computer simulations. His explanation shows how particles are able to gain polarity in one of their two hemispheres. As they collide and separate, the hemispheres that never come in contact with each other gain additional charges, even as the opposite hemispheres – the ones that attach to other particles – lose theirs through neutralization. This perpetual repolarization would allow particles that were neutral at first to develop very high charges. Details of the research appear online in the April 11 issue of the respected scientific journal Nature Physics.