I'll let the experts explain:

Using conventional lenses, it's not possible to focus light waves or sound waves to a spot size smaller than half the wavelength of the light. To get around these limitations, a lens must refract, or literally bend light backward. No naturally occurring materials have a negative index of refraction, but some materials carefully designed in the lab, called metamaterials, do.

Fang, a mechanical science professor at the University of Illinois at Urbana-Champaign, is using an array (pictured above) of specially shaped, water-filled cavities in a piece of aluminum, which supposedly work together to refract the sound by resonating in a particular way. It's all sort of unclear, and nobody has yet figured out how to get around that whole wavelength issue, but this could be the start of even crazier stealth technology, which is always fun to see—or not see. Get it? Because it's stealth. [Technology Review]

Conclusion 1: This Is Atlantis, Dammit!

The enigmatic lines were found under the sea off the north-western coast of Africa. This location is awfully close to one of the spots Plato, Legendary Smart Dude, had pinpointed as a possible resting place of Atlantis. In addition, the site is about the same size as Plato described. And if we accept Google's explanation, why is this the first such grid we've seen, in this very suspicious location?

Conclusion 2: It's Not Atlantis, Dammit!

Google claims that the lines are remnants of the sonar traces left by boats as they surveyed the area. Plus, Plato described Atlantis as being designed as a series of concentric circles, not a grid. Sub-argument: Plato's description of Atlantis was fictional, and the entire internet is really bored.

I think the arguments speak for themselves. ATLANTIS IS OBVIOUSLY REAL! [CNET, Google]

A Royal Navy source told the Times:

It is remarkably difficult to detect a modern submarine with sonar and we work very hard with our own submarines, as do our allies, in making them as quiet as possible so they are not detectable.

And he's serious about that—even after realizing they'd hit something, the French crew couldn't tell what it was. They wrote the object off as a shipping container, only to find out that they had actually collided with another submarine upon docking three days later, after the government had deduced the collision from routine information exchanges with the British.

The problem was that both submarines use passive sonar to map out their surroundings, which doesn't give away their location with the 'pings' of active sonar, and is somewhat less sensitive. Without these 'pings', it was nearly impossible for either sub's passive sonar to detect the other's, leading to the collision and subsequent confusion.

In reality, the whole thing was a bit more subdued than initial reports (or our imaginations) led us to believe. The subs, which were traveling very slowly, just sort of bonked into on another, and the only critical damage to either vessel was to the French sub's sonar system. [Times Online]

What happens is the bats' internal echolocation, which tracks movement, attracts them to the blades of wind turbines, which presents another fairly obvious problem. But a University of Calgary researcher, puzzled by bats dying off in large numbers around wind farms in southern Alberta has found that those that don't get cut down by the blades (surprisingly only 50%) are actually dying from exploded lungs, or barotrauma; the low pressure areas around the spinning rotors, as explained by our friend Bernoulli, cause the bats' tiny air sacs to burst. Even those that do get knocked out of the sky by the blades have their lungs popped beforehand—of the 188 dead bats in the study, 90% had barotrauma as the cause of death.

I'm thinking this is going to have to remain one of those problems without an immediate solution. Hopefully the bats will evolve to realize that the massive spinning turbine blades do not equal a tasty insectoid meal. [New Scientist, Photo: Zeusandhera]

Those mad scientists over at Wicked Lasers provided some pictures of the process. For those sensitive to the graphic misuse of A/V equipment, parental discretion is advised.

Upgrades. – Mark Wilson

Making the Sonar [hacked gadgets]
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Biomimetic Bat-Bot [Treehugger]