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Submission + - NASA Successfully Tests The 'Impossible' Microwave Thruster (valuewalk.com) 1

Joe_NoOne writes: NASA has achieved a breakthrough in space propulsion technology, albeit at a small experimental level. Researchers at the space agency have successfully tested the microwave thrusters that can work without any propellant. It was considered impossible because the propulsion system violates the law of conservation of momentum.

NASA said the electric propulsion device generated a force that is not attributable to any classical electromagnetic phenomena. The amount of thrust generated was only 30-50 MicroNewtons (mN), even less than the weight of an iPhone. But the fact that the system generated even a small amount of thrust without any onboard source of fuel clearly violates the law of conservation of momentum

Submission + - Why is Sun's Corona 300 times hotter than its surface ? (scienceworldreport.com) 4

Taco Cowboy writes: There has been a phenomenon that has puzzled scientists for decades. Sun's Corona has been measured to be 300 times hotter than Sun's surface

"That's a bit of a puzzle," said Jeff Brosius, space scientist at NASA's Goddard Space Flight Center. "Things usually get cooler farther away from a hot source. When you're roasting a marshmallow you move it closer to the fire to cook it, not farther away."

Only recently Scientists have gathered some of the strongest evidence to explain what makes the sun's outer atmosphere so much hotter than its surface.

The new observations come from just six minutes worth of data from one of NASA's least expensive type of missions, a sounding rocket. The EUNIS mission, short for Extreme Ultraviolet Normal Incidence Spectrograph, was launched on April 23, 2013 to gather a new snapshot of data every 1.3 seconds to track the properties of material over a wide range of temperatures in the complex solar atmosphere

The sun's visible surface, called the photosphere, is some 6,000 Kelvins, while the corona regularly reaches temperatures which are 300 times as hot and EUNIS was able to pick up a wavelength of light corresponding to that 10 million degree material

The culprit is known as " Nanoflares " — a constant peppering of impulsive bursts of heating, none of which can be individually detected — provide the mysterious extra heat

"The fact that we were able to resolve this emission line so clearly from its neighbors is what makes spectroscopists like me stay awake at night with excitement," said Brosius. "This weak line observed over such a large fraction of an active region really gives us the strongest evidence yet for the presence of nanoflares"

Submission + - Battery-free Wi-Fi connectivity could fuel 'Internet of Things' (washington.edu)

vinces99 writes: Imagine a world in which your wristwatch or other wearable device communicates directly with your online profiles, storing information about your daily activities where you can best access it – all without requiring batteries. Or, battery-free sensors embedded around your home that could track minute-by-minute temperature changes and send that information to your thermostat to help conserve energy. This not-so-distant “Internet of Things” reality would extend connectivity to perhaps billions of devices. Sensors could be embedded in everyday objects to help monitor and track everything from the structural safety of bridges to the health of your heart. But having a way to cheaply power and connect these devices to the Internet has kept this from taking off.

Now, University of Washington engineers have designed a new communication system that uses radio frequency signals as a power source and reuses existing Wi-Fi infrastructure to provide Internet connectivity to these devices. Called Wi-Fi backscatter, this technology is the first that can connect battery-free devices to Wi-Fi infrastructure. The researchers will publish their results at the Association for Computing Machinery’s Special Interest Group on Data Communication‘s annual conference this month in Chicago. The team also plans to start a company based on the technology.

Submission + - The hacking of NASDAQ (businessweek.com)

puddingebola writes: Businessweek has an account of the 2010 hacking of the NASDAQ exchange. From the article, "Intelligence and law enforcement agencies, under pressure to decipher a complex hack, struggled to provide an even moderately clear picture to policymakers. After months of work, there were still basic disagreements in different parts of government over who was behind the incident and why. “We’ve seen a nation-state gain access to at least one of our stock exchanges, I’ll put it that way, and it’s not crystal clear what their final objective is,” says House Intelligence Committee Chairman Mike Rogers, a Republican from Michigan, who agreed to talk about the incident only in general terms because the details remain classified. “The bad news of that equation is, I’m not sure you will really know until that final trigger is pulled. And you never want to get to that.”"

Submission + - Star Trek "warp drive" crushes diamonds to dust (sciencemag.org)

sciencehabit writes: The world’s largest laser, a machine that appeared as the warp core in "Star Trek into Darkness", has attained a powerful result: It's squeezed diamond, the least compressible substance known, 50 million times harder than Earth's atmosphere presses down on us. The finding should help scientists better understand how material behaves at the great pressures that prevail deep inside giant planets.

Submission + - Microsoft CEO to slash 18,000 jobs, 12,500 from Nokia to go (v3.co.uk)

DW100 writes: Satya Nadella has taken an axe to Microsoft's 127,000-strong workforce by announcing a whopping 18,000 job cuts, including 12,500 from the recently integrated Nokia division. At least 13,000 jobs will go within the next six months.

Submission + - Australia repeals carbon tax (wsj.com)

schwit1 writes: After almost a decade of heated political debate, Australia has become the world's first developed nation to repeal carbon laws that put a price on greenhouse gas emissions.

In a vote that could highlight the difficulty in implementing additional measures to reduce carbon emissions ahead of global climate talks next year in Paris, Australia's Senate on Wednesday voted 39-32 to repeal a politically divisive carbon emissions price that contributed to the fall from power of three Australian leaders since it was first suggested in 2007.

Australia, the world's 12th largest economy, is one of the world's largest per capita greenhouse gas emitters due to its reliance on coal-burning power stations to power homes and industry. In 2011, daily emissions per head amounted to 49.3 kilograms (108 pounds), almost four times higher than the global average of 12.8 kilograms, and slightly ahead of the U.S. figure of 48.2 kilograms.

Submission + - Cosmologists Prove Negative Mass Can Exist In Our Universe

KentuckyFC writes: The idea of negative mass has fascinated scientists since it was first used in the 16th century to explain why metals gain weight when they are oxidised. Since then, theoretical physicists have shown how it could be used to create exotic objects such as wormholes and the Alcubierre warp drive. But cosmologists' attempts to include negative matter in any reasonable model of the cosmos have always run into trouble because negative mass violates the energy conditions required to make realistic universes with Einstein's theory of general relativity. Now a pair of cosmologists have round a way round this. By treating negative mass as a perfect fluid rather than a solid point-like object, they've shown that negative mass does not violate the energy conditions as had been thought and so must be allowed in our universe. That has important consequences. If positive and negative mass particles were created in the early universe, they would form a kind of plasma that absorbs gravitational waves. Having built a number of gravitational wave observatories that have to see a single gravitational wave, astronomers might soon need to explain the absence of observations. Negative mass would then come in extremely handy.

Submission + - Japan arrests woman for making a printable 3d model of her vagina

antifoidulus writes: The BBC is reporting that a Japanese woman has been arrested for making a 3d model of her vagina that can be printed using a 3d printer. Megumi Igarashi had sent the printable model to people who sent her money to create it. A police spokesman told AFP news agency she had distributed data that could "create an obscene shape". While giant phalluses are a common spectacle at Japanese fertility festivals, apparently vaginas are still considered "taboo". Ms. Igarashi is fighting the charges.

Submission + - Fossils of Cambrian predator preserved with brain impressions

An anonymous reader writes: Researchers on Wednesday described fossilized remains unearthed in China showing in fine detail the brain structures of a bizarre group of sea creatures that were the top predators more than half a billion years ago. The 520-million-year-old creature, one of the first predators of its day, sported compound eyes, body armor and two spiky claws for grabbing prey. "The animals of the Cambrian are noted for being a collection of oddballs that are sometimes difficult to match up with anything currently living on Earth. But even among these oddities, Anomalocarids stand out (as their name implies). The creatures propelled themselves with a series of oar-like paddles arranged on their flanks, spotted prey with enormous compound eyes, and shoveled them into a disk-like mouth with large arms that resided at the very front of their bodies—although some of them ended up as filter feeders."

Submission + - Nearly 25 years ago, IBM helped save Macintosh (computerworld.com)

dcblogs writes: Apple and IBM, which just announced partnership to bring iOS and cloud services to enterprises, have helped each other before. IBM played a key role in turning the Macintosh into a successful hardware platform at a point when it — and the company itself — were struggling. Nearly 25 years ago, IBM was a part of an alliance that gave Apple access to PowerPC chips for Macintosh systems that were competitive, if not better performing in some benchmarks, than the processors Intel was producing at the time for Windows PCs. In 1991, Apple was looking for a RISC-based processor to replace the Motorola 68K it had been using in its Macintosh line. "The PCs of the era were definitely outperforming the Macintoshes that were based on the 68K," he said. "Apple was definitely behind the power, performance curve," said Nathan Brookwood, principal analyst at Insight 64. The PowerPC processor that emerged from that earlier pairing changed that. PowerPC processors were used in Macintoshes for more than a decade, until 2006, when Apple switched to Intel chips.

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