A counter-rotation conundrum
Just when astronomers felt they were getting a handle on how solar systems form, along comes a young star 500 light-years away. It has a disk of dust and gas whirling around it. So far, so good. But the inner part of the disk is whirling in the opposite direction from the rest of the disk.
"We've never seen anything like this," says Anthony Remijan, an astronomer with the National Radio Astronomy Observatory's Very Large Array (VLA) in Socorro, N.M.
He and colleague Jan Hollins, with NASA's Goddard Spaceflight Center in Greenbelt, Md., expect the star one day to host counter-rotating planets. The duo suspects that instead of getting its disk material from one cloud of interstellar dust and gas, the star drew material from two clouds - each with its own direction of rotation. The results are set for publication in the April 1 issue of the Astrophysical Journal.
Nuclear fusion makes the sun shine. It soon may be harnessed for homeland security and bridge repairs as well.
Researchers have developed a table-top, room-temperature device that uses fusion to generate neutrons. The researchers say their work could lead to small, battery-operated neutron "factories" whose particles could be used to hunt for explosives in luggage or search for hidden cracks in steel girders.
The device is a modified version of a small particle accelerator physicists built last year at the University of California at Los Angeles. The UCLA version used a special crystal that generates an electrical field when it is chilled, then warmed. The new device, developed at Rensselaer Polytechnic Institute in Troy, N.Y., improves on it by using two crystals for a more-powerful electric field. And it operates at room temperature. UCLA's device had to be cooled with liquid nitrogen, which increases the device's size, cost, and complexity. The results appear in the Feb. 10 issue of Physical Review Letters.
Sixty years ago this week, the US Army unveiled the Electronic Numerical Integrator and Computer, a computational behemoth that is widely regarded as the granddaddy of today's PCs and laptops. ENIAC's parts list included hundreds of thousand of components and weighed more than 30 tons. Since then, computers have revolutionized the way the world works and plays. And over the years, they have generated their share of fearless forecasts. For example:
"Where a calculator on the ENIAC is equipped with 18,000 vacuum tubes and weighs 30 tons, computers in the future may have only 1,000 vacuum tubes and perhaps weigh 1-1/2 tons." - Popular Mechanics, 1949.
"I think there is a world market for maybe five computers." - Thomas John Watson, IBM chairman, 1943.
"There is no reason for any individual to have a computer in his home." - Ken Olson, founder of Digital Equipment Corp., 1977.
"Experts agree that the best type of computer for your individual needs is one that comes on the market about two days after you actually purchase some other computer." - Dave Barry, humorist.