Health & Science
A piece of a fallen ‘star’; Fusion in a laboratory?; Let the kid fidget; The value of circumcision
A piece of a fallen ‘star’For the first time, astronomers have been able to track an asteroid as it traveled through space, lit up the Earth’s atmosphere as a shooting “star,’’ and landed on the ground in pieces. In October 2008, scientists at Arizona’s Catalina Sky Survey observatory first sighted an asteroid they named 2008 TC3. They tracked the 88-ton space rock hurtling through space toward Earth, until it finally hit our atmosphere in the early morning of Oct. 6, 2008, over northern Sudan. The asteroid exploded, lit up the sky, and came down as a rain of thousands of fist-size chunks of meteorite. A group of scientists and students set out to search for these fragments, and found 47 pieces of flaky, black rock strewn over an 18-mile stretch of the Nubian desert. Analysis showed that 2008 TC3 was a rare, “F class’’ asteroid, which has been detected through telescopes but never seen on the ground. Astronomers believe this type of asteroid was formed at the birth of our solar system, 4.6 billion years ago, when rocks and gas were coalescing into planets. Researchers tell National Geographic that the meteorite may serve as “a Rosetta stone’’ that will help them better understand how the solar system formed.
Fusion in a laboratory?Cold fusion would be the answer to the world’s energy problems, generating limitless energy out of such commonplace substances as seawater, with no radioactivity and at very low cost. Fusion, the energy source for the sun and all the stars in the universe, occurs when atoms are forced together at immense pressures, causing nuclei to combine or “fuse.’’ Twenty years ago, University of Utah scientists claimed they’d succeeded in producing a “cold’’ fusion reaction in the laboratory, but nuclear physicists disputed their conclusions. Now, another group of scientists says it has succeeded in combining atomic nuclei at room temperature, producing energy—and this time, the claim is being taken more seriously. Pamela Mosier-Boss and her team at Space and Naval Warfare Systems Command in San Diego used a very similar method to the one used in the disputed experiment two decades ago, and found that it does indeed yield high-energy neutrons. Some scientists find the evidence convincing. “In my view, it’s a cold fusion effect,’’ Peter Hagelstein of the Massachusetts Institute of Technology tells New Scientist. Some skeptics remain unconvinced that fusion occurred, but Steven Krivit, editor of New Energy Times, said the study was “big’’ and would lead to further research.
Let the kid fidgetTeachers may be frustrated by children who squirm in their seats, roll their heads, or play with their school supplies during class. But a new study has found that for kids with attention deficit/hyperactivity disorder, fidgeting isn’t a sign of inattention—it’s their way of staying focused. Children with ADHD have trouble learning because their cortexes aren’t as alert in normal classroom situations, making it hard for them to put complex ideas and facts into their short-term memories. That’s why these kids often respond well to Ritalin, which is a stimulant. (It’s also why adults find that caffeine helps them to concentrate better.) In a study of 8- to 12-year-old boys, says Time, ADHD researcher Mark Rapport of the University of Central Florida found that kids with the disorder did concentrate better when they could fidget and swivel in their chairs. So parents and teachers shouldn’t nag kids to sit still, Rapport says. “When they are doing homework, let them fidget, stand up, or chew gum,’’ he says. “Severely limiting their activity could be counterproductive.’’ The value of circumcision The rate of circumcision in the U.S. has declined to 56 percent, as many parents have come to question the value of surgically removing a baby boy’s foreskin. But a new study of 3,000 men in Uganda has found further evidence that circumcision does significantly reduce the risk of infection by sexually transmitted diseases, says The New York Times. In this group of men, circumcision reduced the risk of herpes infection by 25 percent, and human papillomavirus (HPV) infection by 35 percent. Earlier studies had found that circumcision reduced the risks of infection by the AIDS virus by up to 60 percent. “Evidence now strongly suggests that circumcision offers an important prevention opportunity and should be widely available,” say Dr. Matthew Golden and Dr. Judith Wasserheit, the study’s authors. Researchers aren’t sure why circumcision offers protection, but theorize that foreskins may serve as a hiding place for viruses and may develop micro-tears during sex that offer viruses easy access to the body.