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| Sunday, 16 October 2005 |
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Junior Observer |  |
| News Business Features Editorial
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Backpacks which light your way
Well, we have got some good news for you. Someday, if you don't mind carrying a heavy load, your backpack might even light your way home. Scientists from the University of Pennsylvania in Philadelphia and the Marine Biological Laboratory in Woods Hole, Massachusetts, USA have invented a backpack that makes electricity from energy produced while its wearer walks. The backpack's electricity-creating powers depend on springs used to hang a cloth pack from its metal frame. The frame sits against the wearer's back, and the whole pack moves up and down as the person walks. A mechanism with gears collects energy from this motion and transfers it to an electrical generator. Surprisingly, the researchers found, people walk differently when they wear the springy packs. As a result, wearers use less energy than when lugging regular backpacks. Also, the way the new packs ride on wearers' backs makes them more comfortable than standard packs, the inventors say. In the new backpack, the pack frame is attached to the body but the cargo-carrying part hangs from springs attached to the frame. As you walk, the cargo compartment jiggles and a special toothed rod (green) moves up and down, turning a gear mounted on a generator that produces electricity. The backpack could be especially useful for soldiers, scientists, mountaineers, and emergency workers who typically carry heavy backpacks. These people often rely on global positioning system (GPS) receivers, night-vision goggles, and other battery-powered devices to get around and do their work. Because the pack can make its own electricity, users don't need to give up space in their packs to lots of extra batteries. For the rest of us, power-generating backpacks could make it possible to walk, play video games, watch TV, and listen to music, all at the same time. Electricity-generating packs aren't on the market yet, but if you do get one eventually, just make sure to look both ways before crossing the street. - Science News for Kids ############ Mystery of the milky seas Out at sea, there are nights when huge patches of the water's surface glow with an eerie (scary) white light. Sailors have been telling tales of these 'milky seas' for hundreds of years, but only now scientists have finally documented the phenomenon. First, Steve Miller of the Naval Research Laboratory and his co-workers scoured (searched thoroughly) ship records for mentions of glowing seas. They found a carefully recorded sighting that dated back to January 25, 1995. It had occurred in the Indian Ocean off the coast of Somalia. The scientists then looked at satellite images taken of this area around that time. The images confirmed the event, and analyses showed that the glowing water covered 15,400 square kilometres. The glow appeared three nights in a row, and the patch moved with the currents. The soft, white light, the researchers say, probably comes from an unusually large population of glowing bacteria called Vibrio harveyi, which live together with microscopic algae. As satellite sensor technology improves, scientists hope to be able to detect glow patches as they happen. Then, investigators can race to the scene and learn more about what's going on. - Science News for Kids |
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As schoolchildren, we all use backpacks. They are convenient because
backpacks can hold your books, lunch, and even a change of clothes,
leaving your hands free to do other things. 
