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10 Places To Visit Before You Die

Today is Earth Day, and to celebrate, we’re showing off Mother Nature’s beautiful side with truly stunning images of this beautiful planet.

 

Wisteria Flower Tunnel – Japan

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Tulip Fields – Netherlands Read more →

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Mount Roraima – South America

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Lake Retba – Sengal

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Solar du Uyuni – Bolivia

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Red Beach – China

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Bern, Switzerland

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The Pearl Waterfall, Jiuzhaigou Valley, China

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Cinque Terre, Rio Maggiore, Italy

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Keukenhof Gardens – Netherlands

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Three-million-year-old landscape beneath Greenland Ice Sheet

Glaciers are commonly thought to work like a belt sander. As they move over the land they scrape off everything — vegetation, soil, and even the top layer of bedrock. So scientists were greatly surprised to discover an ancient tundra landscape preserved under the Greenland Ice Sheet, below two miles of ice.

“We found organic soil that has been frozen to the bottom of the ice sheet for 2.7 million years,” said University of Vermont geologist Paul Bierman — providing strong evidence that the Greenland Ice Sheet has persisted much Read more →

longer than previously known, enduring through many past periods of global warming.

He led an international team of scientists that reported their discovery on April 17 in the journal Science.

Antique landscapes

Greenland is a place of great interest to scientists and policymakers since the future stability of its huge ice sheet — the size of Alaska, and second only to Antarctica — will have a fundamental influence on how fast and high global sea levels rise from human-caused climate change.

“The ancient soil under the Greenland ice sheet helps to unravel an important mystery surrounding climate change,” said Dylan Rood a co-author on the new study from the Scottish Universities Environmental Research Centre and the University of California, Santa Barbara, “how did big ice sheets melt and grow in response to changes in temperature?”

The new discovery indicates that even during the warmest periods since the ice sheet formed, the center of Greenland remained stable; “it’s likely that it did not fully melt at any time,” Vermont’s Bierman said. This allowed a tundra landscape to be locked away, unmodified, under ice through millions of years of global warming and cooling.

“The traditional knowledge about glaciers is that they are very powerful agents of erosion and can effectively strip a landscape clean,” said study co-author Lee Corbett, a UVM graduate student who prepared the silty ice samples for analysis. Instead, “we demonstrate that the Greenland Ice Sheet is not acting as an agent of erosion; in fact, at it’s center, it has performed incredibly little erosion since its inception almost three million years ago.”

Rather than scraping and sculpting the landscape, the ice sheet has been frozen to the ground, “a refrigerator that’s preserved this antique landscape,” Bierman said.

Cosmic signal

The scientists tested seventeen “dirty ice” samples from the bottommost forty feet of the 10,019-foot GISP2 ice core extracted from Summit, Greenland, in 1993. “Over twenty years, only a few people had looked hard at the sediments from the bottom of the core,” Bierman said. From this sediment, he and a team at the University of Vermont’s Cosmogenic Nuclide Laboratory extracted a rare form of the element beryllium, an isotope called beryllium-10. Formed by cosmic rays, it falls from the sky and sticks to rock and soil. The longer soil is exposed at Earth’s surface, the more beryllium-10 it accumulates. Measuring how much is in soil or a rock gives geologists a kind of exposure clock.

The researchers expected to only find soil eroded from glacier-scoured bedrock in the sediment at the bottom of the ice core. “So we thought we were going looking for a needle in haystack,” Bierman said. They planned to work diligently to find vanishingly small amounts of the beryllium — since the landscape under the ice sheet would have not been exposed to the sky. “It turned out that we found an elephant in a haystack,” he said; the silt had very high concentrations of the isotope when the team measured it on a particle accelerator at Lawrence Livermore National Laboratory.

“On a global basis, we only find these sorts of beryllium concentrations in soils that have developed over hundreds of thousands to millions of years,” said Joseph Graly, who analyzed the beryllium data while at the University of Vermont.

The new research, supported by funding from the National Science Foundation, shows that “the soil had been stable and exposed at the surface for somewhere between 200,000 and one million years before being covered by ice,” notes Ben Crosby, a member of the research team from Idaho State University.

To help interpret these unexpected findings, the team also measured nitrogen and carbon that could have been left by plant material in the core sample. “The fact that measurable amounts of organic material were found in the silty ice indicates that soil must have been present under the ice,” said co-author Andrea Lini at the University of Vermont — and its composition suggests that the pre-glacial landscape may have been a partially forested tundra.

“Greenland really was green! However, it was millions of years ago,” said Rood, “Greenland looked like the green Alaskan tundra, before it was covered by the second largest body of ice on Earth.” To confirm their findings about this ancient landscape, the researchers also measured beryllium levels in a modern permafrost tundra soil on the North Slope of Alaska. “The values were very similar,” said Bierman, “which made us more confident that what we found under Greenland was tundra soil.”

Future tense

Many geologists are seeking a long-term view of the history of the Greenland Ice Sheet, including how it moves and has shaped the landscape beneath it — with an eye toward better understanding its future behavior. It’s 656,000 square miles of ice, containing enough water, if fully melted, to raise global sea levels twenty-three feet — “yet we have very little information about what is happening at the bed with regards to erosion and landscape formation,” said Corbett.

What is clear, however, from an abundance of worldwide indicators, is that global temperatures are on a path to be “far warmer than the warmest interglacials in millions of years,” said Bierman. “There is a 2.7-million-year-old soil sitting under Greenland. The ice sheet on top of it has not disappeared in the time in which humans became a species. But if we keep on our current trajectory, the ice sheet will not survive. And once you clear it off, it’s really hard to put it back on.”

‘Dressed’ laser aimed at clouds may be key to inducing rain, lightning

The adage “Everyone complains about the weather but nobody does anything about it” may one day be obsolete if researchers at the University of Central Florida’s College of Optics & Photonics and the University of Arizona further develop a new technique to aim a high-energy laser beam into clouds to make it rain or trigger lightning.

The solution? Surround the beam with a second beam to act as an energy reservoir, sustaining the central beam to greater distances than previously possible. The secondary “dress” beam refuels and helps prevent the dissipation of the high-intensity primary beam, which on its own would break down quickly. A report on the project, “Externally refueled optical filaments,” was recently published in Nature Photonics.

Water condensation and lightning activity in clouds are linked to large amounts of static charged particles. Stimulating those particles with the right kind of laser holds the key Read more →

to possibly one day summoning a shower when and where it is needed.

Lasers can already travel great distances but “when a laser beam becomes intense enough, it behaves differently than usual — it collapses inward on itself,” said Matthew Mills, a graduate student in the Center for Research and Education in Optics and Lasers (CREOL). “The collapse becomes so intense that electrons in the air’s oxygen and nitrogen are ripped off creating plasma — basically a soup of electrons.”

At that point, the plasma immediately tries to spread the beam back out, causing a struggle between the spreading and collapsing of an ultra-short laser pulse. This struggle is called filamentation, and creates a filament or “light string” that only propagates for a while until the properties of air make the beam disperse.

“Because a filament creates excited electrons in its wake as it moves, it artificially seeds the conditions necessary for rain and lightning to occur,” Mills said. Other researchers have caused “electrical events” in clouds, but not lightning strikes.

But how do you get close enough to direct the beam into the cloud without being blasted to smithereens by lightning?

“What would be nice is to have a sneaky way which allows us to produce an arbitrary long ‘filament extension cable.’ It turns out that if you wrap a large, low intensity, doughnut-like ‘dress’ beam around the filament and slowly move it inward, you can provide this arbitrary extension,” Mills said. “Since we have control over the length of a filament with our method, one could seed the conditions needed for a rainstorm from afar. Ultimately, you could artificially control the rain and lightning over a large expanse with such ideas.”

So far, Mills and fellow graduate student Ali Miri have been able to extend the pulse from 10 inches to about 7 feet. And they’re working to extend the filament even farther.

“This work could ultimately lead to ultra-long optically induced filaments or plasma channels that are otherwise impossible to establish under normal conditions,” said professor Demetrios Christodoulides, who is working with the graduate students on the project.

“In principle such dressed filaments could propagate for more than 50 meters or so, thus enabling a number of applications. This family of optical filaments may one day be used to selectively guide microwave signals along very long plasma channels, perhaps for hundreds of meters.”

Other possible uses of this technique could be used in long-distance sensors and spectrometers to identify chemical makeup. Development of the technology was supported by a $7.5 million grant from the Department of Defense.

 

 

 

Source: sciencedaily

Scientists discover brain’s anti-distraction system

Two Simon Fraser University psychologists have made a brain-related discovery that could revolutionize doctors’ perception and treatment of attention-deficit disorders.

This discovery opens up the possibility that environmental and/or genetic factors may hinder or suppress a specific brain activity that the researchers have identified as helping Read more →

us prevent distraction.

The Journal of Neuroscience has just published a paper about the discovery by John McDonald, an associate professor of psychology and his doctoral student John Gaspar, who made the discovery during his master’s thesis research.

This is the first study to reveal our brains rely on an active suppression mechanism to avoid being distracted by salient irrelevant information when we want to focus on a particular item or task.

McDonald, a Canada Research Chair in Cognitive Neuroscience, and other scientists first discovered the existence of the specific neural index of suppression in his lab in 2009. But, until now, little was known about how it helps us ignore visual distractions.

“This is an important discovery for neuroscientists and psychologists because most contemporary ideas of attention highlight brain processes that are involved in picking out relevant objects from the visual field. It’s like finding Waldo in a Where’s Waldo illustration,” says Gaspar, the study’s lead author.

“Our results show clearly that this is only one part of the equation and that active suppression of the irrelevant objects is another important part.”

Given the proliferation of distracting consumer devices in our technology-driven, fast-paced society, the psychologists say their discovery could help scientists and health care professionals better treat individuals with distraction-related attentional deficits.

“Distraction is a leading cause of injury and death in driving and other high-stakes environments,” notes McDonald, the study’s senior author. “There are individual differences in the ability to deal with distraction. New electronic products are designed to grab attention. Suppressing such signals takes effort, and sometimes people can’t seem to do it.

“Moreover, disorders associated with attention deficits, such as ADHD and schizophrenia, may turn out to be due to difficulties in suppressing irrelevant objects rather than difficulty selecting relevant ones.”

The researchers are now turning their attention to understanding how we deal with distraction. They’re looking at when and why we can’t suppress potentially distracting objects, whether some of us are better at doing so and why that is the case.

“There’s evidence that attentional abilities decline with age and that women are better than men at certain visual attentional tasks,” says Gaspar, the study’s first author.

The study was based on three experiments in which 47 students performed an attention-demanding visual search task. Their mean age was 21. The researchers studied their neural processes related to attention, distraction and suppression by recording electrical brain signals from sensors embedded in a cap they wore.

NASA’s Kepler program finds the most Earth-like planet yet

Pretty exciting news from the Kepler Radar Observatory on Thursday – in the form of Kepler-186f. That’s an Earth-like planet in its sun’s happy zone – not too far, not too close, but just the right distance zone to open the promise of life.

The Kepler Mission has been on the lookout via satellite for just such Read more →

a neighbor in the Milky Way. Here’s a look at what some very excited scientists rolled out in the announcement:

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Astronomers have discovered what they say is the most Earth-like planet yet detected — a distant, rocky world that’s similar in size to our own and exists in the Goldilocks zone where it’s not too hot and not too cold for life.

The find, announced Thursday, excited planet hunters who have been scouring the Milky Way galaxy for years for potentially habitable places outside our solar system.

“This is the best case for a habitable planet yet found. The results are absolutely rock solid,” University of California, Berkeley astronomer Geoff Marcy, who had no role in the discovery, said in an email.

The planet was detected by NASA’s orbiting Kepler telescope, which examines the heavens for subtle changes in brightness that indicate an orbiting planet is crossing in front of a star. From those changes, scientists can calculate a planet’s size and make certain inferences about its makeup.

The newfound object, dubbed Kepler-186f, circles a red dwarf star 500 light-years from Earth in the constellation Cygnus. A light-year is almost 6 trillion miles.

The planet is about 10 percent larger than Earth and may very well have liquid water — a key ingredient for life — on its surface, scientists said. That is because it resides at the outer edge of the habitable temperature zone around its star — the sweet spot where lakes, rivers or oceans can exist without freezing solid or boiling away.

The planet probably basks in an orange-red glow from its star and is most likely cooler than Earth, with an average temperature slightly above freezing, “similar to dawn or dusk on a spring day,” Marcy said.

The discovery was detailed in Friday’s issue of the journal Science.

View image on Twitter

 

Lead researcher Elisa Quintana at NASA’s Ames Research Center said she considers the planet to be more of an “Earth cousin” than a twin because it circles a star that is smaller and dimmer than our sun. While Earth revolves around the sun in 365 days, this planet completes an orbit of its star every 130 days.

“You have a birthday every 130 days on this planet,” she said.

Scientists cannot say for certain whether it has an atmosphere, but if it does, it probably contains a lot of carbon dioxide, outside experts said.

“Don’t take off your breathing mask if you ever land there,” said Lisa Kaltenegger, a Harvard and Max Planck Institute astronomer who had no connection to the research.

Despite the differences, “now we can point to a star and know that there really is a planet very similar to the Earth, at least in size and temperature,” Harvard scientist David Charbonneau, who was not part of the team, said in an email.

Since its launch in 2009, Kepler has confirmed 961 planets, but only a few dozen are in the habitable zone. Most are giant gas balls like Jupiter and Saturn, and not ideal places for life. Scientists in recent years have also found planets slightly larger than Earth in the Goldilocks zone called “super Earths,” but it is unclear if they are rocky.

The latest discovery is the closest in size to Earth than any other known world in the habitable region.

Kepler-186f is part of a system of five planets, all of which are roughly Earth’s size. However, the other planets are too close to their star to support life.

Astronomers may never know for certain whether Kepler-186f can sustain life. The planet is too far away even for next-generation space telescopes like NASA’s overbudget James Webb, set for launch in 2018, to study in detail.

Kepler completed its prime mission and was in overtime when one of the wheels that keep its gaze steady failed last year. NASA has not yet decided whether to keep using the telescope to hunt for planets on a scaled-back basis.

 

 

 

 

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