Is a Dark-Matter Galaxy Orbiting the Milky Way?

People used to think that the heavens were a vast clockwork, with planets and moons moving in circular orbits like a vast timepiece. Recent advances have shown us that this stellar machinery is far vaster than they ever suspected - even our galaxy has satellites, mini-galaxies orbiting the Milky Way and some of them could be very interesting indeed.

We now know about two dozen of these satellite galaxies. One of the most recent is "Segue 1", uncovered by the Sloan Digital Sky Survey (SDSS), whose extremely low light-to-mass ratio makes it a particularly significant cosmic find. Despite having a mass of a million suns it is nowhere near as luminous as astronomers would expect, with only a couple of hundred stars visible. They think "How can so much matter be so dark?", then they go "Dark matter!" and at this point we like to believe their monocle flies out and they dash down the street shouting Eureka.

Of course, the actual physics of arriving at this conclusion is a tiny bit more complicated, but the result is the same: Marla Geha (Yale professor of astronomy) and colleagues believe that it's a galaxy composed mainly of dark matter. A handy thing to have around when you're trying to study the stuff or even prove that it exists.

The SDSS has made many such observations possible, picking out objects in the sky which have the bad manners not to twinkle twinkle bright enough, despite being little stars. These mini-galaxies and other previously unobservable objects offer a wealth of data on galaxy formation, evolution, and even the composition of the universe itself.

Posted by Luke McKinney

Original here

Lift could take passengers straight into space

By Jon Swaine

Japanese scientists are attempting to build a lift that will take passengers 62,000 miles into space.

The project could see the realisation of a vision that has inspired science fiction writers for generations.

	A Nasa image of how a 'space elevator' might look

The lift's carriages, which will themselves require new feats of engineering, would move up and down 22,000 mile-long cables.

Those cables would need to be stronger and lighter than any material ever woven.

They would be anchored to the ground and disappear into the sky, eventually reaching a satellite docking station orbiting above the Earth.

Scientists hope that as well as carrying human passengers, the carriages could also haul huge, solar-powered generators that could power homes and businesses back on Earth. It could also remove barrels of nuclear waste, dumping them into space.

"Just like travelling abroad, anyone will be able to ride the elevator into space," Shuichi Ono, chairman of the Japan Space Elevator Association, told The Times.

Japan's promise to spend £5 billion on the project has sparked swift reaction from other quarters: several competing space lift projects are now believed to be under way, with Nasa among those involved.

An international conference is to be held in Japan in November, aiming to draw up a detailed timetable for the machine's production.

One of the biggest challenges is expected to be producing a fabric for the lift's cables. It must be extremely light while also resilient enough to resist the various matter that it will be struck by in space. It is expected that an answer will be found in carbon nanotubes - microscopic particles woven into fibres.

Professor Yoshio Aoki, a director of Japan's Space Elevator Association and a professor of precision machinery engineering at Nihon University, said the cables would need to be 180 times stronger than steel. It would also need to four times stronger than the strongest carbon nanotube fibre ever produced, he added.

On the question of how the lift's carriages will be powered, Prof Aoki said: "We are thinking of using the technology employed in our bullet trains.

"Carbon nanotubes are good conductors of electricity, so we are thinking of having a second cable to provide power all along the route."

It is thought the concept of the lift was first envisioned by the great sci-fi writer Arthur C Clarke, in his 1979 book The Fountains of Paradise.

Original here

Scientists succeed in spoofing GPS signals

Good luck blaming those speeding tickest on GPS spoofing now

Zoom

<>

Here's a story to send a shiver down the spine of anyone who relies on their GPS sat nav or mobile. Scientists at Cornell University have managed to trick a GPS receiver into accepting signals from rogue transmitters instead of the genuine orbiting satellites.

It took a year of electronic tinkering, but boffins today demonstrated how a phony receiver could be placed near a navigation device, where it would track, modify, and retransmit the signals from the GPS satellite constellation. Gradually, the victim navigation device would accept the counterfeit navigation signals.

Burn your sat nav immediately

"GPS is woven into our technology infrastructure, just like the power grid or the water system," said Professor Kintner, director of the Cornell GPS Laboratory. "If it were attacked, there would be a serious impact." Mums lost on the way to Iceland, salesmen slightly late for meetings, geeks disorientated in PC World, that kind of thing.

The US government has been worried about GPS spoofing since at least 2003, when it published seven possible counter-measures against such attacks. "We're fairly certain we could spoof all of these, and that's the value of our work," said one of the Cornell researchers.

If my pizza delivery guy is late again, I'm blaming these guys. But I still want my free garlic bread.

By Mark Harris

Original here

Babies have a sense of rhythm, which could be used to help them develop

By Daily Mail Reporter

Babies have a sense of rhythm from early on in life

It will be months before they talk, walk or even sit up. But at just a day old, babies have a strong sense of rhythm, say researchers.

Newborns are also sensitive to pitch and melody, they found.

Experts said that introducing a child to music at an early age could enhance these innate musical abilities and also help them learn to talk.

The fledgling musical talent was discovered by Hungarian researchers during a study of more than 100 boys and girls who were only one or two days old.

They played the babies music as they slept and measured their brain activity.

The researchers found that their brains computed changes in beat, tone and melody.

For instance, if a key beat was missed from a rhythmic pattern, the baby's brain registered the change.

A change in pitch, similar to that between male and female voices, also provoked a reaction.

The Hungarian Academy of Sciences study was part of a threeyear European project on how the brain processes music and other sounds, co-ordinated by Dr Susan Denham, of Plymouth University.

She said: 'What is perhaps most significant is that not only do babies' brains register changes in beat, pitch and simple melodic patterns but they do so more or less automatically, as they are fast asleep during these experiments.

'People come into the world with brains that are wired-up to detect patterns'.

Dr Denham added: 'A lot of music reflects the rhythms and contents of speech. If you are listening to music you will also probably be more sensitive to speech rhythm.'

Original here

NYC Trade Center dig exposes Ice Age landscape

NEW YORK - Crews excavating the World Trade Center site this summer for the foundations of a new skyscraper have uncovered features carved into the bedrock by glaciers about 20,000 years ago, including a 40-foot-deep pothole.

Exposing the solid rock beneath at the ground zero site in lower Manhattan is critical for supporting what will be Tower 4 of the new World Trade Center, being built by Silverstein Properties.

"You want to make sure you're not perching something on a ledge," said Anthony Pontecorvo, a supervising structural engineer at Mueser Rutledge Consulting Engineers, which is working on the project.

While removing the overlying soil is an engineering necessity, the digging has given scientists a rare window into the deep past and formations like the huge pothole.

"There are areas in local parks that have small vertical potholes exposed," Cheryl J. Moss, the senior geologist at Mueser Rutledge, told The New York Times. "But I'm not aware of anything in the city with a whole, self-contained depression on this scale."

Moss and Pontecorvo plan to deliver a lecture about the geology of the site Wednesday at the Tribute W.T.C. Visitor Center next to the ground zero site.

The reminders of the power of glaciers won't be around for long. The pothole and other features are being covered, filled in or blasted away.

"It's nice to look at, but it's all got to go," said Robert B. Reina, a supervising structural engineer at Mueser Rutledge.

Original here

Polar bears resort to cannibalism as Arctic ice shrinks

By Marsha Walton

(CNN) -- Summer is over in the northern hemisphere, but it's been another chilling season for researchers who study Arctic sea ice.

Disappearance of Arctic ice cover may affect storm systems, storm tracks and crops, according to researchers.

1 of 2

"It's definitely a bad report. We did pick up little bit from last year, but this is over 30 percent below what used to be normal," said Walt Meier, a research scientist with the National Snow and Ice Data Center in Boulder, Colorado.

This past summer, the Arctic sea ice dwindled to its second lowest level. Arctic sea ice is usually 1 to 3 meters, or as much as 9 feet thick. It grows during autumn and winter and shrinks in the spring and summer.

Scientists have monitored sea ice conditions for about 50 years with the help of satellites. Changes in the past decade have been alarming to climate researchers and oceanographers.

"It is the second lowest on record. ... If anything, it is reinforcing the long-term trend. We are still losing the ice cover at a rate of 10 percent per decade now, and that is quite an increase from five years ago," Meier said. "We are still heading toward an ice cover that is going to melt completely in the summertime in the Arctic."

Arctic ice helps regulate and temper the climate in many other parts of the world. The less ice there is, the more dramatic the impact. Huge sheets of ice reflect solar radiation, keeping our planet cool. When that ice melts, huge expanses of darker, open ocean water absorb the heat instead, warming things up.

Although few humans live in the Arctic, the disappearance of this ice cover can have effects far beyond the few residents and the wildlife of this harsh region. Ice cover loss can influence winds and precipitation on other continents, possibly leading to less rain in the western United States and creating more in Europe.

"That warming is going to spread to the lower latitudes, to the United States, and it's going to affect storm systems and storm tracks, the jet stream; that's going to affect crops and all sorts of things," Meier predicted.

So, just how much ice is disappearing?

Less than 30 years ago, there would still be 7 million square kilometers or 2.5 million square miles of ice left at the end of an Arctic summer. That's now dropped by almost 40 percent. See how much Arctic sea ice has disappeared »

"Seven million square kilometers roughly corresponds to an area of the lower 48 United States. So back in the early 1980s, the lower 48 states would be covered in sea ice in the summer," Meier said. "Now we've essentially lost sea ice east of the Mississippi River and even beyond. So that's a significant amount of area."

The best known consequence of disappearing sea ice in the Arctic is the loss of the polar bear habitat. Learn more about polar bears and their habitat »

"The Arctic sea ice melt is a disaster for the polar bears," according to Kassie Siegel, staff attorney for the Center for Biological Diversity. "They are dependent on the Arctic sea ice for all of their essential behaviors, and as the ice melts and global warming transforms the Arctic, polar bears are starving, drowning, even resorting to cannibalism because they don't have access to their usual food sources."

Scientists have noticed increasing reports of starving Arctic polar bears attacking and feeding on one another in recent years. In one documented 2004 incident in northern Alaska, a male bear broke into a female's den and killed her.

In May, the U.S. Department of Interior listed the polar bear as a "threatened" species under the Endangered Species Act. In a news release, U.S. Interior Secretary Dirk Kempthorne stated, "loss of sea ice threatens and will likely continue to threaten polar bear habitat. This loss of habitat puts polar bears at risk of becoming endangered in the foreseeable future, the standard established by the ESA for designating a threatened species."

What is the future for Arctic sea ice? Some scientists believe that in just five years, the Arctic may be ice-free during the summer.

"The Arctic is kind of the early warning system of the climate," Meier said. "It is the canary in the coal mine, and the canary is definitely in trouble."

Original here

New Electric Car From Chrysler by 2010 // Pics

Chrysler Shocks Electric Car Timeline With New Plug-ins for 2010: Live First Look (With Dodge EV Test Drive!)

AUBURN HILLS, Mich. — In a surprise move here this morning amid struggling sales numbers from its dealers and fuel-efficient buzz from competitors, Chrysler announced that it's charging into the electric vehicle market a lot sooner than expected. The automaker just unveiled a trio of battery-powered vehicles—including an all-electric, 200-mile-range Dodge sports car that we revved up near its 120-mph top speed on the test track and think could give the Tesla Roadster a run for its money—and plans to bring one of them to market by 2010, aligning Chrysler with the timetable for General Motors' Chevy Volt.

Chrysler officials, who reinforced their case for an entirely hybrid fleet at least partially powered by batteries, said at a news conference on Tuesday that they're aiming to sell all three cars—extended-range plug-in versions of a Jeep Wrangler and Chrysler Town & Country were unveiled in addition to the Dodge EV—within a decade. But how fast they reach dealerships, CEO Bob Nardelli cautioned, may well depend on whether the federal government comes through with a package of loan guarantees for Detroit's Big Three.

"You're going to see the electrification of all vehicles" in the years ahead, said Frank Klegon, Chrysler's executive vice president for product development. That will range from full battery power to simpler systems, like Stop/Start, which temporarily shuts off an engine at a stoplight. Indeed, Klegon forecasts that "at least 50 percent of the market" will consists of pure EVs or extended-range electric vehicles (EREVs) by around 2020.

The former category very well could include the Dodge EV. If the look is familiar, that's because the body and platform are borrowed from the Lotus Europa sportscar (not the Lotus Elise, as you might first imagine). There have been minor modifications made to squeeze in a 200-kilowatt motor and a lithium-ion battery pack that, in production, would yield somewhere between 150 and 200 miles on a charge. Doug Quigley, engineering lead for Chrysler's ENVI advanced powertrain division that is also working on three concepts we saw at the Detroit auto show this year, said the rear-drive two-seater should be able to launch from 0-to-60 in under 5 seconds. He wouldn't say how much under, but the goal is to be faster than the Lotus with a target of the mid-13-second range for the 1/4-mile run. And if our 20-minute test drive on the 2-mile track here is any indication, that should be very doable. The new EV handles like a charm, with sharp steering and some serious giddyup—we could feel the 100-plus-mph beneath us while hearing nary a thing.

The Jeep and Chrysler plug-ins, like the Volt, both fall into the extended-range category to combine battery and gasoline power. And like GM, Chrysler is aiming for a 40-mile range on electric charges alone, claiming that both vehicles should be able to hit 400 miles with an 8- or 9-gal. tank of gas. Chrysler modified its newest Jeep Wrangler for the white plug-in truck unveiled here today—and that should mean the same off-road capabilities. The minivan is a slightly upmodded version of the popular Town & Country, with the underbody tubs—used to hide the Stow-and-Go seats in a conventional Chrysler minivan—housing the large battery packs.

So which of the three new electric cars will come to market first? Chrysler isn't saying—in part, President Tom LaSorda acknowledged, because the company has yet to decide. There are serious questions to answer, including what batteries the company will use—and who will supply them. The good news, Klegon said, is that the number of potential battery vendors has "tripled" in recent years. Coming up with reliable, high-power batteries is a clear challenge, but there's also the issue of cost. Lithium-ion technology is phenomenally expensive, but Chrysler, like its competitors, believes that in high volume, costs should plunge.

Meanwhile, the automaker is launching a new joint venture with General Electric (where Chrysler CEO Nardelli first rose to prominence) aimed at developing even more advanced battery systems. One approach that the partners plan to study would pair two different types of batteries, such as lithium-ion and sodium-sulfur, to see if they can yield improved levels of power and performance.

Admittedly short on cash and struggling with sales, Chrysler officials recently have spent a lot of time in Washington, D.C., meeting with the lawmakers who would have to approve a loan guarantee package that might exceed $25 billion for Detroit. Nardelli said he was "very impressed" with the feedback he has gotten, but stressed that without that assistance, there will have to be some "very tough decisions" made about what Chrysler can afford to fund.

Chrysler actually put a fourth product on display here, too: the buggy-size "Peapod" Neighborhood Electric Vehicle (NEV) from the automaker's GEM division. NEVs are, effectively, gussied-up electric golf carts; they have found a small but comfortable niche in places like retirement villages and college campuses. Newly renamed Green Eco-Mobility, GEM will launch the 25-mph Peapod and its 30-mile-range sometime next year, with more eco-friendly rides to come from the division—and its parent company, suddenly back in the game in a big way—in the new decade. —Paul Eisenstein

Original here