Physics Buzz

Ghost knifefish use electricity as a sixth sense. Now scientists exploring tropical jungle streams have unearthed secrets regarding how these fish use electric signals to communicate in the wild. This work could shed light on how nervous systems in general process weak, ambiguous sensory data, which could help improve the design of bionic devices that interact with the nervous system.

Emperor penguins are lords of the cold. They thrive in frigid conditions that would make human popsicles out of anyone relying on only the hair nature gave them for protection. Many researchers have bundled up and braved harsh Antarctic winters to study these fascinating birds and their strategies for survival. In 2011, a team of international scientists reported that tight-knit huddles of Emperor penguins exhibit wave-like motions. Every 30-60 seconds waves will propagate throughout the huddle, which can consist of thousands of penguins at a time, allowing penguins at the huddle’s chilly outskirts to move inward to the warm center and those at the center to relinquish their turn. The team’s observations generated more questions than answers. Was there a lead penguin that triggers the wave each time? How do the waves compare with the collective behavior of other masses such as bird flocks, fish schools and traffic jams? And why do the waves move throughout the huddle in the dire

It swims in the ocean, dances on water and glides through air, what is it? Not much of a riddle since the solution is in the title, but how bizarre that a single family of fish evolved to achieve three feats of which most animals can perform only one. Patricia Yang, a graduate student of mechanical engineering at the Georgia Institute of Technology, raises flying fish in a tank in Taiwan. She is one of the few scientists around the world to study flying fish in a laboratory setting instead of their natural environment. In the lab, she could get a close look at the initial steps any fish must make before taking flight. One being breaking the surface-tension barrier between water and air. Credit: Theron Trowbridge While the fish were still in their juvenile state, measuring no longer than two centimeters, Yang and a group of scientists from Georgia Tech and the National Sun Yat-sen University in Taiwan trained them to launch into the air on command. Using high-speed videography,

Via:  Flavia FF As promised, today's Physics Central Podcast is about the physics of mosh pits! Ever notice when you're walking through a crowded place that people tend to organize themselves into lanes (without anyone telling them to)? You can actually make the comparison between that sort of behavior and the way a bunch of birds manage to form a flock, even when they don't have an exact flight plan. But organizing yourself into a line with other people makes sense; it could just be that we all see what's happening and make the most logical decision. But data showing the collective behavior of very large crowds of people in more extreme cases (like a mass panic) show that collective behaviors still emerge. So in the extreme case of a mosh pit, do those same collective behaviors emerge? Do people suddenly act like birds in a flock or particles in a gas? Some early research by Jesse Silverberg and Matthew Bierbaum of Cornell University shows that yes: collecti

In 1961, Yuri Gagarin became the first person to reach outer space and orbit the Earth. But Gagarin's flight may not have been possible without the help of many brave, furry astronauts that went into space before him. Throughout the 1950s and 1960s, the Soviet Union launched dozens of dogs into space to test flight conditions and space environments. Some of the dogs went on to become national heroes, but the program also had its share of tragedies. A stamp from the United Arab Emirates commemorating Laika—the first dog to orbit the Earth. Image Courtesy NIH.