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Cosmic Antimatter Excess Confirmed

Antimatter Detector
© Naval Research Laboratory/NASADetector. The Fermi telescope, visible here as the large silver "box" atop the satellite, has confirmed an anomalous antimatter signal in the cosmic ray spectrum.

In 2008, the Italian satellite PAMELA picked up an unusual signal: a spike in antimatter particles whizzing through space. The discovery, controversial at the time, hinted that physicists might be coming close to detecting dark matter, an enigmatic substance thought to account for 85% of the matter in the universe. Now, new data from NASA's Fermi Gamma-ray Space Telescope confirm the spike. Alas, they also undermine its interpretation as a sign of dark energy.

Theorists generally believe that when two dark matter particles collide, they should annihilate each other to produce ordinary particles, such as an electron and its antimatter twin, a positron. Thanks to Einstein's iconic equivalence between energy and mass, E=mc2, each of those particles should emerge with an energy essentially equal to the mass of the original dark matter particle. So when the PAMELA team saw a spike in the ratio of positrons to the more abundant electrons over a particular slice of the energy spectrum, some physicists got excited. Perhaps PAMELA was seeing evidence of such annihilations.

However, because positrons are produced elsewhere in the universe, including in pulsars and neutron stars, the result was inconclusive at best - although it stirred quite a frenzy. At a conference where the preliminary PAMELA data was being presented, physicists used cell phones to snap photos of the Italian team's slides, then wrote and published papers on the Internet about the data's dark matter significance, all before the results were prepared for submission to a refereed journal.

The plot thickened in 2009 when the Fermi team released data from its own satellite's look at the cosmic ray spectrum, which showed no signals out of the ordinary. However, in that analysis, the Fermi group considered the sum total of all charged particles, electrons, and positrons. That was because the telescope was designed to measure neutral gamma rays and has no onboard magnet for distinguishing negatively charged electrons and positively charged positrons.

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Could Electrical Sprites Hold the Key to Extraterrestrial Life?

Sprites
© University of Alaska FairbanksFull color image of a red lightning sprite.
In 1989, meteorologists discovered sprites. Not the spirits, elves, or pixies that pepper Shakespearean comedies but their equally elusive electrical namesakes. Lightning sprites are large scale electrical discharges inside the clouds above storms that make the upper atmosphere glow, sort of like a fluorescent lightbulb.

Meteorologists have already determined that sprites likely aren't unique to Earth. In fact, this elusive form of lightning might be common throughout the solar system. Now, researchers at Tel Aviv University are asking whether the presence of sprites on other planets could indicate the presence of organic material in their atmospheres.

Though not an uncommon phenomena, sprites are incredibly hard to find and observe. They can only be captured with highly sensitive high speed cameras. Sprites occur in the Earth's Mesosphere, layer between the stratosphere and the thermosphere - about 50 km (31 miles) to 90 km (56 miles) high. At this altitude, the gases that make up our atmosphere are much thinner and unable to hold heat from the Sun making the average temperature a chilly 5°F (-15°C) to as low as -184°F (-120°C).

Cloud Lightning

Tall water waves behave unexpectedly

tall water waves
© Jon WilkeningA snapshot of a standing water wave from the animation below.
In investigating the behavior of large-amplitude standing water waves, mathematician Jon Wilkening of the University of California, Berkeley, has discovered that the waves' behavior cannot be explained as simply as previously proposed. Questions regarding the dynamics of standing water waves have gone unanswered for decades since numerical simulations have not been powerful enough to explore wave behavior with sufficient accuracy. In the new study published in Physical Review Letters, Wilkening has used numerical simulations with a sufficiently high resolution (capable of achieving 26 digits of accuracy) to help better understand the dynamics that occur at the crests of standing water waves.

In his study, Wilkening explains that standing water waves (those that slosh in and out symmetrically) and traveling water waves (those that travel across the surface of the water with a constant shape) have very different "limiting behavior."

"Standing waves and traveling waves both come in families," Wilkening explained to PhysOrg.com. "Larger amplitude waves are more sharply peaked at the crest than lower amplitude waves. 'Limiting behavior' refers to the behavior when you increase the value of the parameter to its maximum value."

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Inside the Brains of Psychopaths

Crime Scene
© Flynt | Dreamstime.comPsycopaths are estimated to make up 1 percent of the population and up to 25 percent of male offenders in federal correctional settings.

Differences in psychopaths' brains may help explain their anti-social behavior, according to new research.

Psychopaths are identified as highly selfish, and lacking in emotion and conscience. Experts estimate that about 1 percent of the general population and as many as 25 percent of male offenders in federal correctional settings are psychopaths. Research looking into the minds of psychopaths has found not only differences in their brains but also, at least in one recent study, speech patterns.

In the new study, which relied on scans of the brains of psychopaths incarcerated in Wisconsin, the researchers found reduced connections between a part of the brain associated with empathy and decision-making, known as the ventromedial prefrontal cortex (vmPFC), and other parts of the brain.

Using two different types of images, the researchers compared the brains of male prisoners diagnosed as psychopaths with those of prisoners who did not receive this diagnosis. Among the psychopathic prisoners, the researchers found weaker connections between the vmPFC and other parts of the brain, including the amygdala.

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Why It Pays to Taste Words and Hear Colors

Colored Numbers
© hkeita | ShutterstockOf the more than 60 known types of synesthesia, grapheme-color synesthesia, in which people see every number or letter tinged with a particular color, is the most common.

While most of us see sights and hear sounds, some people also hear colors and taste words, a mysterious phenomenon called synesthesia, which occurs when stimulating one of the five senses triggers experiences in an unrelated sense. Now researchers suggest this unusual trait can provide numerous mental benefits, potentially explaining why evolution has kept it around.

Scientists first discovered synesthesia in the 19th century, noting that certain people saw every number or letter tinged with a particular color, even though they were written in black ink. This condition, known as grapheme-color synesthesia, is the most common of the more than 60 known variants of synesthesia.

Although synesthesia can occur due to drug use, brain damage, sensory deprivation and even hypnosis, research has revealed that 2 percent to 4 percent of the general population naturally experiences synesthesia, with the phenomenon tending to run in families. Recent work analyzing the brains of people with grapheme-color synesthesia has revealed it is caused by an increased number of connections between sensory regions of the brain.

A key question regarding synesthesia is why the phenomenon has survived when it might not seem to provide any benefit. Now scientists, in a review of past research in the field, are finding answers from those who have it - synesthetes.

Sherlock

US Scientists Confirm Discovery Of Mastodon Bones in Daytona Beach

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© Unknown
Officials Shut Down Daytona Beach Site After Crews Dig Up Ice Age Mammal

Local officials said scientists at the Museum of Arts and Sciences confirmed Tuesday that the prehistoric animal bones found at a Daytona Beach construction site were that of a Mastodon -- a large mammal belonging to the Ice Age.

Crews working at a storm water project off Nova Road found the ancient bones Friday, and officials said they have shut down the construction site to preserve the discovery.

According to scientists, the fossilized mastodon was between 13,000 and 150,000 years old. The tusked mammal would have weighed several tons, like a prehistoric elephant.

"We're finding some significant pieces -- tusks and vertebrae. We don't know completely what's down there yet, so it gets more exciting the more we dig," Zach Zacharias, of the Museum of Arts and Sciences, said.

Whether there is a full or a partial skeleton, or even more than one creature is still unclear, but scientists said more and more bones have been emerging.

"(Mastodons) were big, hairy animals," Zacharias said.

Teacher and amateur paleontologist Don Brunning and his wife are local experts the museum relies on, and he said the mastodon would have been a contemporary of the giant ground sloth, which was also uncovered locally.

Saturn

Monster Storm Rages on Saturn

Saturn's atmosphere and its rings are shown here in a false color composite made from three images taken in near infrared light through filters that are sensitive to varying degrees of methane absorption. Red and orange colors in this view indicate clouds that are deep in the atmosphere. Yellow and green colors, most noticeable near the top of the view, indicate intermediate clouds. White and blue indicate high clouds and haze. The rings appear as a thin horizontal line of bright blue because they are outside of the atmosphere and not affected by methane absorption.

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© NASA/JPL-Caltech/Space Science InstituteThe head of Saturn's huge northern storm is well established in this view captured early in the storm's development by NASA's Cassini spacecraft in late 2010.
This view looks toward the southern, unilluminated side of the rings from just below the ringplane.

Bulb

Scientists: Faster-than-light finding still holds

The chances have risen that Einstein was wrong about a fundamental law of the universe.

Scientists at the world's biggest physics lab said Friday they have ruled out one possible error that could have distorted their startling measurements that appeared to show particles traveling faster than light.

Many physicists reacted with skepticism in September when measurements by French and Italian researchers seemed to show subatomic neutrino particles breaking what Nobel Prize-winning physicist Albert Einstein considered the ultimate speed barrier.

Better Earth

Breathtaking Time Lapse Video of Earth from Space Station

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© ISS/NASA
Maybe you've heard. There is a one-million pound tinker toy floating 200 miles above the surface of the Earth. The International Space Station zips around the Earth at 17,000 miles per hour and witnesses 17 sunrises and sunsets every day. What you may not know is that in addition to all their other duties, the space station astronauts are pretty good photographers.

The images below were captured from August to October, 2011 from the deck of the International Space Station. The stunning sequences show the Aurora Borealis, night passes over cities, and crackling lightning storms. Images were taken with a special low-light 4K camera and they give some of the best perspectives yet on what it is like to travel aboard the space station.

Sherlock

Whales in the Desert: Fossil Bonanza Poses Mystery

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© AP Photo/Museo Paleontologico de CalderaIn this Aug. 11, 2010 photo released by Chile's Paleontological Museum of Caldera, a paleontologist from the museum prepares a whale fossil at the site where many prehistoric whale fossils were discovered in the Atacama desert near Copiapo, Chile. The fossil is enclosed in a plaster jacket to protect it during transport back to the museum.
More than 2 million years ago, scores of whales congregating off the Pacific Coast of South America mysteriously met their end.

Maybe they became disoriented and beached themselves. Maybe they were trapped in a lagoon by a landslide or a storm. Maybe they died there over a period of a few millennia. But somehow, they ended up right next to one another, many just meters (yards) apart, entombed as the shallow sea floor was driven upward by geological forces and transformed into the driest place on the planet.

Today, they have emerged again atop a desert hill more than a kilometer (half a mile) from the surf, where researchers have begun to unearth one of the world's best-preserved graveyards of prehistoric whales.

Chilean scientists together with researchers from the Smithsonian Institution are studying how these whales, many of the them the size of buses, wound up in the same corner of the Atacama Desert.

"That's the top question," said Mario Suarez, director of the Paleontological Museum in the nearby town of Caldera, about 700 kilometers (440 miles) north of Santiago, the Chilean capital.

Experts say other groups of prehistoric whales have been found together in Peru and Egypt, but the Chilean fossils stand out for their staggering number and beautifully preserved bones. More than 75 whales have been discovered so far - including more than 20 perfectly intact skeletons.