Science News
General relativity caught in action around black hole
Wobbling disk of orbiting debris shows yanking and twisting of spacetime
By Andrew Grant
GENEVA — An effect of general relativity that is barely measurable on Earth has been spotted in full force around a black hole.
Physicists detected the signature of a black hole twisting the fabric of spacetime around it. The discovery offers the best evidence yet of this relativity-driven twisting effect, known as frame dragging, around a black hole where it is most powerful. The research was reported December 16 at the Texas Symposium on Relativistic Astrophysics.
Researchers captured the extreme frame dragging by analyzing X-rays emanating from a disk of star debris swirling around a black hole about 28,000 light-years away in the Milky Way. The data suggest that the disk’s matter is on a wild ride as the spacetime it occupies gets yanked and warped by the spinning black hole.
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Uncovering the science of sand dune ‘booms’
By Andrew Grant
It starts as a hum, barely audible above the howl of the winds shimmying between sand dunes. Then it builds. Within seconds, the sound resembles a World War II–era prop plane flying low overhead. But there’s nothing there. “It’s very mystical and eerie,” says Nathalie Vriend, a mechanical engineer and geophysicist at the University of Cambridge.
This resounding roar, called a boom, has intrigued desert explorers for centuries. Yet only recently have scientists demystified the source of booms and softer, shorter-lived burps that emanate from deserts’ sandy slopes. Much of the new insight has come from Vriend. Her extremely hands-on research, which includes sliding down towering dunes, has revealed that tumbling sand induces pressure pulses that course above and below the surface to produce a cacophony of peculiar noises.
Vriend wasn’t exactly born to be a desert explorer. She grew up in a Dutch village with a climate closer to Seattle than to the Sahara. At Caltech in 2004, she read a magazine article on desert booms and burps — and was inspired to do her Ph.D. research on the topic
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Technology News
Donald Trump wants to shut off the Internet
The Republican presidential candidate suggests that the US cut off Iraq and Syria from the Web.
by Laura Hautala
If terrorists are using the Internet, then take the Internet away.
That's what Donald Trump, the front-runner to be the Republican nominee for president of the United States, suggested last night at the final debate of the year.
Trump tempered the remark by saying the US should shut down the Web in ISIS-controlled Syria and Iraq, but his idea could still be a logistical nightmare.
It was one of many suggestions last night from candidates making grand claims about what they'd do to keep the Internet from helping terrorists and other bad guys. From expanding the NSA's collection of phone call data to hacking China, everything was on the table.
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California’s New Self-Driving Car Rules Are Great for Texas
Alex Davies
California has drafted rules for the public deployment of autonomous cars, finally giving us a look at how regulators will react once self-driving tech is ready to go past the testing phase. The news is not good for anyone looking to let go of the wheel and let the robot do all the work.
The rules, proposed as a draft by the state DMV on Wednesday, lay out a variety of requirements for manufacturers that want to offer autonomous driving to the public. The DMV will host public forums to discuss the regulations, which won’t be finalized before later next year.
The rules seem reasonable at first. To be certified, the car must be tested in a variety of situations by a knowledgeable, independent third party. The customer will get some sort of training, going over how the technology works. The car’s required to carry a data recorder, and the human onboard is responsible for any traffic violations. The manufacturer must pay a $33,000 to $50,000 processing fee, and may have to cover any costs incurred during certification. All the paperwork submitted to the DMV has to be on company letterhead.
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Environmental News
Ice rafts traveling farther and faster across the Arctic Ocean
Contamination risks rise as ice-trapped pollutants go along for the ride
By Thomas Sumner
SAN FRANCISCO — Climate change could turn the Arctic Ocean into an ice autobahn. Sea ice, much of it chunks of floating ice, is becoming younger and thinner as old ice melts. That new ice travels farther and faster than older ice, carrying dirt, organisms and pollution along for the ride, new research shows.
Tracking the movements of Arctic ice over several years, researchers noticed that ever larger areas of ice now make the trek from one side of the ocean to the other. That movement means that the far-flung reaches of the Arctic are becoming more connected, Robert Newton said December 16 at the American Geophysical Union’s fall meeting. That’s a problem, as migrating ice will boost the risk of widespread environmental disaster from events such as oil spills, said Newton, an oceanographer at Columbia University's Lamont-Doherty Earth Observatory in Palisades, N.Y.
“You might imagine that the ice is this pristine environment, but that’s not true,” he said. “The ice in the Arctic is surprisingly polluted, and when the ice travels from one part of the Arctic to the other, it carries all that material with it.”
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Growing parasite threat to finches made famous by Darwin
By Matt McGrath
Finches in the Galapagos Islands are being threatened by a parasitic fly that attacks their young.
A new mathematical model suggests that the birds may succumb to this pest in 50 years.
But the authors say that human intervention could alleviate the risk of extinction.
During his time on the Galapagos in the early 1830s, Charles Darwin noticed that finches on different islands in the chain were quite similar but had large variations in their beaks, depending on the local food source.
Because the islands are so far from the mainland, Darwin concluded that the birds had begun as one species and then started to evolve into separate varieties of finch.
There are between 14 and 18 species on the Galapagos - but this study looked at one of the most common, the medium ground finch. Around 270,000 of these birds are found on Santa Cruz island.
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Medical News
To treat the heart, start with the gut
Potential drug targeting intestinal bacteria stops chain reaction that leads to artery plaque
By Sarah Schwartz
Blocking gut reactions could help defend against heart disease.
Intestinal microbes break down the essential nutrient choline, abundant in meat and eggs, into a compound that leads to hardening of the arteries. A drug candidate that prevents the microbes from making this chemical conversion can reduce both the amount of this compound and the extent of artery damage in mice, researchers report online December 17 in Cell.
Manipulating gut bacteria to treat various diseases has clinical promise, says physician and microbiologist Martin Blaser of the New York University Langone Medical Center. “It’s a very exciting idea that may change the future therapies that are available for doctors.” He notes that this study addresses a particularly important and common disease: atherosclerosis, in which fatty plaques build up inside arteries, increasing the risk of heart attack and stroke.
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A brain link to autism
Scientists find neurotransmitter that ties in with disorder's behavior
Harvard University
In a discovery that could offer valuable new insights into understanding, diagnosing and even treating autism, Harvard scientists for the first time have linked a specific neurotransmitter in the brain with autistic behavior.
Using a visual test that is known to prompt different reactions in autistic and normal brains, a research team led by Caroline Robertson, a Junior Fellow of the Harvard Society of Fellows, was able to show that those differences were associated with a breakdown in the signaling pathway used by GABA, one of the brain's chief inhibitory neurotransmitters. The study is described in a December 17 paper in Current Biology.
"This is the first time, in humans, that a neurotransmitter in the brain has been linked to autistic behavior - full stop," Robertson said. "This theory - that the GABA signaling pathway plays a role in autism - has been shown in animal models, but until now we never had evidence for it actually causing autistic differences in humans."
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Space News
Peake: What will the astronaut be doing in space?
David Shukman
After seeing the Canadian astronaut Chris Hadfield performing with his guitar or Scott Kelly of Nasa doing airborne somersaults, many might wonder if the ISS has a serious point.
The reality is that everyone sent up there faces a very busy timetable which involves managing a range of experiments that make use of the state of weightlessness.
The space station is a giant laboratory and every inhabitant is expected to get involved in the research.
Just by being in space, Tim himself will serve as a lab rat, allowing his body to be monitored in great detail - with 23 different sets of measurements in all.
By the end of his mission, he will be all too familiar with the regular processes of gathering samples of his blood and urine. Space research is not for the squeamish.
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Wolf 1061c: Potentially Habitable Super-Earth Spotted 14 Light-Years Away
by Natali Anderson
Wolf 1061 is a red dwarf star located in the constellation Ophiuchus, only 14 light-years from Earth.
The three exoplanets discovered orbiting this star are between 1.3 and 5.2 times the size of our own, according to the team led by Dr Duncan Wright of the University of New South Wales.
“We have found strong Doppler signals in data for Wolf 1061 that indicate the presence of three planets: a 1.36 Earth minimum-mass planet with an orbital period P = 4.888 d (Wolf 1061b), a 4.25 Earth minimum-mass planet with orbital period P = 17.867 d (Wolf 1061c), and a probable 5.21 Earth minimum-mass planet with orbital period P = 67.274 d (Wolf 1061d),” the team wrote in a paper accepted for publication in the Astrophysical Journal Letters (arXiv.org preprint).
“All of the planets are of sufficiently low mass that they may be rocky in nature.”
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Odd News
Precise method underlies sloppy madness of dog slurping
Mechanisms of how dogs drink revealed
Virginia Tech
Stories about lap dogs are everywhere, but researchers at the Virginia Tech College of Engineering can tell the story of dog lapping.
Using photography and laboratory simulations, researchers studied how dogs raise fluids into their mouths to drink. They discovered that sloppy-looking actions at the dog bowl are in fact high-speed, precisely timed movements that optimize a dogs' ability to acquire fluids.
Their discovery appears today in the Proceedings of the National Academy of Sciences.
Researchers also compared what they learned about how dogs drink with what they knew from previous studies of cats. The scientists discovered that even though feline and canine mouths structurally are similar, their approaches to drinking are as different as -- cats and dogs.
"We know cats and dogs are quite different in terms of behavior and character," said Sunghwan "Sunny" Jung, an associate professor of biomedical engineering and mechanics. "But before we did fundamental studies of how these animals drink fluids, our guess was dogs and cats drink about the same way. Instead we found out that dogs drink quite differently than cats."
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