By D.M. LevinePosted 03.07.2011 at 12:56 pm 0 Comments
On February 10, 2009, a U.S. and a Russian satellite collided 500 miles above Siberia, adding at least 2,000 chunks to the roughly 100 million pieces of debris currently orbiting Earth. These scraps of satellites, abandoned rocket parts, jettisoned fuel and flecks of paint travel between 7,000 and 18,000 miles an hour, colliding with increasing frequency, which could lead to a feedback loop known as the Kessler syndrome.
Painful sound waves could keep wetsuit-clad terrorists away from ships
By Gregory MonePosted 03.22.2006 at 2:00 am 0 Comments
Since the bombing of the U.S.S. Cole in 2000, protecting docked ships-both military and commercial-has been a big priority in the fight against terrorism. The Department of Homeland Security has already awarded $489 million to help guard the nation´s ports, spurring a number of innovative ideas, the latest of which is an underwater system that blasts enemy swimmers with painful acoustic waves. Patented by the Raytheon Corporation last October, the system is the brainchild of former Navy and Raytheon acoustics expert Frederick Di Napoli. His scheme is simple: Generate a region of high-pressure, low-frequency sound around the ship, creating a sort of sonic fence that â€shocksâ€ anything that swims through it. Although a diver would probably flee from pain, Di Napoli says, "you could really dial up the pressure and make it lethal if you had to."