Giant lasers could control the weather

Zeus, God of the Sky, may be out of work, as scientists at the University of Central Florida believe they've developed a technique -- which involves pointing a high powered laser at the sky -- to induce clouds to drop rain and hurl thunderbolts. Scientists have known that water condensation and lightning activity in storm clouds are associated with large amounts of static charged particles. In theory, stimulating those particles with a laser is the key to harnessing Zeus-like powers. The hard part, scientists say, is creating a laser beam with the right combination of range, precision and strength. "When a laser beam becomes intense enough, it behaves differently than usual -- it collapses inward on itself," explained Matthew Mills, a graduate student in the UCF Center for Research and Education in Optics and Lasers. "The collapse becomes so intense that electrons in the air's oxygen and nitrogen are ripped off creating plasma -- basically a soup of electrons." But students at UCF's College of Optics & Photonics have collaborated with researchers at the University of Arizona to create a "dressed laser" that they think might be up for the challenge of controlling the weather. The dressed laser is a high-power laser beam surrounded by a second beam, which acts as a refueling agent, sustaining the strength and accuracy of the central beam over longer distances. "Since we have control over the length of a filament with our method, one could seed the conditions needed for a rainstorm from afar," said Mills. "Ultimately, you could artificially control the rain and lightning over a large expanse with such ideas." The students recently published their research findings in the journal Nature Photonics. Their efforts were supported by a $7.5 million grant from the Department of Defense.