Physics & Mathematics

‘Heartbeats’ may keep galaxies churning

Until now, astronomers haven’t been able to offer a full explanation for why the Milky Way and other galaxies produce new stars at a relative snail’s pace. While they have known for decades that high turbulence keeps huge clouds of hydrogen gas from condensing into stars, they haven’t identified all the causes of the galactic perturbations. In a coming report researchers in San Diego say they have discovered that a well-known, but overlooked source of heating?regular outbursts of ultraviolet radiation from clusters of very large, bright stars?may play a significant role in keeping the Milky Way’s gas continually stirred up.

Common diabetes drug successfully used to treat pituitary tumor

Using a common diabetes drug, researchers in Los Angeles have successfully treated pituitary tumors that cause a potentially life-threatening condition known as Cushing’s syndrome. The most common type of Cushing’s syndrome is caused by prolonged high-level exposure of a hormone called ACTH (adrenocorticotropin), which is secreted in excess by tumors of the pituitary gland, situated at the base of the brain and, which controls growth, metabolism and reproduction. Although the disorder is rare, it affects more women than men by a ratio of 5:1. Symptoms include weight gain with rounding of the face; increased fat in the neck; thinning skin; excess hair growth on the face neck, chest abdomen and thighs; muscle weakness and bone loss (osteoporosis); high blood sugar; diabetes; and high blood pressure.

Scientists Boost Tally at Uranus

A new moon of the planet Uranus has been discovered and confirmed by a team of astronomers at NASA’s Jet Propulsion Laboratory. This most-recently discovered natural satellite, named S/2001 U 1, brings the total number of confirmed uranian moons to 21. The new kid on the block — and five others like it — have very irregular, eccentric orbits that don’t share the same orbital plane as the larger moons of Uranus. Ranging in size from 10 to 20 kilometers, these moons are thought to be remnants of ancient collisions that occurred at the early stage of planetary formation.

Aluminum shows strange behavior; research solves old mystery

Aluminum — one of nature’s best conductors of electricity conductors of electricity — may behave like a ceramic or a semiconductor in certain situations, according to an Ohio State University scientist and his colleagues. Among the findings that appear in the current issue of the journal Science: When it comes to forming tiny structures in computer chip circuits and nanotechnology, aluminum may endure mechanical stress more than 30 percent better than copper, which is normally considered to be the stiffer metal

Chandra casts cloud on alternative to dark matter

You can't see me, but I'm thereNew evidence from NASA’s Chandra X-ray Observatory challenges an alternative theory of gravity that eliminates the need for dark matter. The observation also narrows the field for competing forms of dark matter, the elusive material thought to be the dominant form of matter in the universe. An observation of the galaxy NGC 720 shows it is enveloped in a slightly flattened, or ellipsoidal cloud of hot gas that has an orientation different from that of the optical image of the galaxy. The flattening is too large to be explained by theories in which stars and gas are assumed to contain most of the mass in the galaxy. “The shape and orientation of the hot gas cloud require it to be confined by an egg-shaped dark matter halo,” said a researcher involved in the stoudy. “This means that dark matter is not just an illusion due to a shortcoming of the standard theory of gravity ? it is real.”

New planet detection technique can spot even small worlds around distant stars

An extrasolar planet has been discovered using a new technique that will allow astronomers to detect planets no other current method can. Planets around other stars have been previously detected only by the effect they have on their parent star, limiting the observations to large, Jupiter-like planets and those in very tight orbits. The new method uses the patterns created in the dust surrounding a star to discern the presence of a planet that could be as small as Earth or in an orbit so wide that it would take hundreds of years to observe its effect on its star.

Freeway living not for the weak of lung

Get a little distance from the matter.In case there was any doubt, researchers in — where else? — Los Angeles have determined that living near a freeway exposes you to a lot more pollution than if you lived further away. Specifically, a UCLA team found people who live, work or travel within 165 feet downwind of a major freeway or busy intersection are exposed to potentially hazardous particle concentrations up to 30 times greater than normal background levels.

Speeding star indicates mondo black hole in middle of Milky Way

Researchers say they’ve successfully tracked a star racing around a dark mass at the center of our Milky Way galaxy, offering strong support for the theory that a black hole is at the center of our little corner of space. Astronomers at the Max Planck Institute for Astrophysics tracked the orbit of the closest known star to the black hole candidate Sagittarius A*, a dark mass 3,000,000 times the mass of the sun. Following the star for 10 years, they found that it does indeed orbit Sagittarius A*. Approaching the black hole’s maw, the star reaches its highest velocity, whizzing past it at 5,000 kilometers per second.

Discovery of Big Space Object Renews Debate About Pluto’s Status

The identifying of a massive, 745-mile-diameter object at the far reaches of our solar system has reopened a debate regarding the planetary status of that ninth pile from the sun, Pluto.
National Geographic reports that the newly-noticed space item is named Quaoar (pronounced “KWAH-o-ar”) and is located in the Kuiper belt, a celestial district 4 billion miles from Earth and relatively close to Pluto. Like the Disney dog-named sphere, Quaoar is composed of rock and ice. Also, its orbit is similar to Pluto’s but differs from the eight other planets. “Pluto is the largest known Kuiper belt object,” a University of Hawaii astronomer says. “Some people think of it as a planet as well. That’s fine, of course, but the reasons for doing so are historical, or sociological at best.”

Organic semiconductors speed shopping

So there you are, zipping around the Qwik-E-Mart, picking up a dozen eggs, some beer, a carton of Abba Zabba and some smokes. You pull up to the checkout stand and your bill is already waiting for you. While you’ve been shopping, tags on your goods have been chatting with the store’s cash register, tallying your total. That’s the scenario in play with a new RF (radio frequency) technology being developed at the University of Arizona Optical Sciences Centre, which uses organic semiconductors that live on thin plastic films. As reported by Beyond2000, the centre recently acquired a deposition machine that can make such films, depositing layers of organic molecules 10 to 100 nanometers thick onto a plastic substrate. Look for real world uses in the next couple years. And leave the cigarettes behind; they’re bad for you.

It’s the little things we remember

On the plus side (Eds: see the minus side below), Hewlett-Packard today is set to announce what it describes as a breakthrough in building nano-sized computer memory. The company has developed a technique for building a matrix of super-thin platinum wires atop a piece of silicon. So small is the resulting 64-bit memory unit that 1,000 of them could fit on the end of a single strand of hair. Even in the world of PCs, that’s small.

Let’s get small, redux

Intel is set to disclose some of its plans in nanotechnology, sure to be key to the company’s chips for decades to come. As reported by CNET’s News.com, Sunlin Chou, senior VP of technology and manufacturing, will discuss some of the plans next week at the Intel Developer Forum in San Jose. Topping the topics likely to be covered: Carbon nanotubes and multigate transistors. Nanotubes are strings of carbon atoms tightly bonded together that show promise in manufacturing everything from tennis rackets to electronics. In computer chips, they can theoretically be used to replace the wispy metal wires that now define a chip’s circuitry. That could make processors smaller and cheaper. Multigate transistors, meanwhile, are a way of addressing the conundrum faced by all chipmakers: The more powerful processors become, the more electricity must flow through them. But as chips shrink in size, the extremely small transistors that control this flow are growing overloaded, something like hooking up a fire hose to a Waterpik nozzle, as CNET puts it. One way around that is to give each transistor more than one gate, an approach that IBM is using in some of its products already. Although analysts say they doubt Intel will copy this entirely, the company likely has a similar approach up its sleeve.

Come fly with me

Boeing has joined a small group of technology bigwigs trying to test a theory that would let engineers negate some of the effects of gravity. The American aerospace giant is using the work of controversial Russian scientist Yevgeny Podkletnov, who claims to have developed a device that can shield objects from the Earth’s pull. Other researchers claim Podkletnov’s work is hokum, but considering the cost savings such a device would represent for air travel, Boeing seems intent on getting to the bottom of it all. The Russian says he found that objects above a superconducting ceramic disc rotating over powerful electromagnets lost weight, the BBC reports. “The reduction in gravity was small, about 2 percent, but the implications — for example, in terms of cutting the energy needed for a plane to fly — were immense.”