In 1999, Hurricane Gert formed on the eastern side of the Atlantic and began the long trip to Bermuda. Along the way, it happened to pass over a hydrophone (an underwater microphone) planted half a mile deep in the mid-Atlantic.
And made a little noise.
A hurricane’s intense wind whips the waves into a churning frenzy, and deep below the surface of the ocean the turbulence creates a “rushing sound whose volume is a direct indicator of the storm's destructive power,” according to an MIT press release.
MIT engineering professor Nicholas Makris, in a paper from a forthcoming Geophysical Research Letters, takes data from Gert's cacophonous performance and proposes a new way to gauge the destructive power of an oncoming cyclone.
In 2006, invisibility cloaks took the world by storm, thanks to a joint effort by mathematicians, physicists and Harry Potter.
This year, however, the physicists have another surprise: you can be invisible AND silent!
Two independent teams of scientists came up the plans for a “cloak of silence,” a device which will be able to create a pocket of silence around an object by redirecting sound waves. Some physicists used to think such a device was mathematically impossible, but the two teams, one from Duke and the other from the Hong Kong University of Science and Technology, say their equations check out. (Image courtesy of Duke.)
The technology can be used by engineers to build better concert halls or hide submarines from sonar, but it’s unlikely that the scientists will come up with a cloak you can throw over your neighbor’s noisy dog. (And if a tree fell in the forest and everyone was wearing an acoustic cloak, would it make a noise?)
Check out the trailer for his forthcoming film project, Terra Nova: The Antarctica Suite -- it's stuffed to the gills with nerdy factoids about ice, wave acoustics, glacier ecology, and the like.
