For the First Time, Astronomers Measure the Mass of a Star Using General Relativity

By Nathaniel Scharping | June 7, 2017 3:27 pm
The white dwarf Stein 2051 B, and the background star, visible as a small dot, that allowed its mass to be measured. (Credit: NASA, ESA, and K. Sahu (STScI))

The white dwarf Stein 2051 B, and the background star, visible as a small dot, that allowed its mass to be measured. (Credit: NASA, ESA, and K. Sahu (STScI))

For the first time, astronomers have measured the mass of a star by observing the way its mass deforms light passing by it.

It’s an observation that Einstein predicted but thought could never actually happen, due to the incredibly precise alignment between distant astronomical objects it entails. But using modern observing tools, researchers recently found and tracked two distant stars as they lined up almost perfectly. Read More

CATEGORIZED UNDER: Space & Physics, top posts
MORE ABOUT: physics, stargazing, stars

These Pine Trees Always Point Toward the Equator, But Why?

By Nathaniel Scharping | June 6, 2017 1:50 pm
Cook Pines line a walkway in Sri Lanka (Credit: eFesenko/Shutterstock)

Cook Pines line a walkway in Sri Lanka (Credit: eFesenko/Shutterstock)

In a world of upright trees, one species dares to be different.

Cook pines, a type of tall, slim evergreen native to a remote island in the South Pacific, at first glance appear to be falling over. Many tilt precariously to the side as if caught in a heavy wind, though no breeze ruffles their foliage. Though it may seem the result of chance, observe a stand of Cook pines, especially in locations far from their native habitat, and a kind of unnerving hive-mentality emerges. The trees all lean the same way, as if commanded by some ur-pine from afar. Read More

CATEGORIZED UNDER: Living World, top posts
MORE ABOUT: plants

Battle of the Breads: Industrial White or Artisanal Whole-Grain?

By Carl Engelking | June 6, 2017 11:00 am
shutterstock_78409531

(Credit: Seregam/Shutterstock)

What’s a more healthful option for a sandwich: industrially processed white bread, or artisanal whole-grain bread?

To those who seek clear-cut, black-and-white answers to burning questions like this one, we apologize preemptively. The answer is both; it simply depends on who’s eating it. Read More

CATEGORIZED UNDER: Health & Medicine, top posts
MORE ABOUT: nutrition

This Exoplanet Is So Hot, It Might Be Evaporating

By Nathaniel Scharping | June 5, 2017 1:44 pm
Kelt-9b and its parent star, which heats its surface to temperatures nearly as hot as the sun. (Credit: NASA/JPL-Caltech/R. Hurt (IPAC))

Kelt-9b and its parent star, which heats its surface to temperatures nearly as hot as the sun. (Credit: NASA/JPL-Caltech/R. Hurt (IPAC))

Astronomers recently announced the discovery of the hottest known giant exoplanet.

Sitting 650 light years away in the constellation Cygnus, Kelt-9b is a scorching ball of gas roughly three times the size of Jupiter. Temperatures there are estimated to reach 7,800 degrees Fahrenheit, hot enough that the planet’s atmosphere may be evaporating away into space, leaving a comet-like tail in its wake. Read More

CATEGORIZED UNDER: Space & Physics, top posts
MORE ABOUT: exoplanets

Algorithm Accurately Reconstructs Faces From A Monkey’s Brain Waves

By Nathaniel Scharping | June 2, 2017 1:38 pm
The library of actual and reconstructed faces used in the experiments. The right sid fo each column was generated soloely from neuron activity. (Credit: oris Tsao/Cell Press)

The library of actual and reconstructed faces used in the experiments. The right side of each column was generated solely from neuron activity. (Credit: Doris Tsao/Cell Press)

When you see a face, what indicates that it is, indeed, a face?

The question has vexed neuroscientists for quite some time, especially because humans seem to be so darn good at recognizing faces — not just in other people, but on sandwiches, in car grills, and even on other planets. The phenomenon even has a name, pareidolia. It is thought that our brain’s ability to conjure faces from random objects is due to something called configural processing—a face is more than the sum of its parts. We don’t need to put together the various components of a face — eyes, nose, ears — we just recognize one when we see it. Read More

CATEGORIZED UNDER: Mind & Brain, top posts
MORE ABOUT: psychology, Senses

The Omentum: A Curtain of Tissue That Keeps Our Guts Working

By Nathaniel Scharping | June 1, 2017 2:14 pm
(Credit: Wikimedia Commons)

(Credit: Wikimedia Commons)

A push to renew research into an understudied gut organ is gaining momentum.

The organ in question? The omentum. It’s a curtain of fatty tissue that hangs down from our stomach and liver and wraps around the intestines, and is known to play a role in immune responses and metabolism, although exactly how that happens is only dimly understood.

Because the omentum doesn’t have a discrete function like, say, our stomach, it can be easy to overlook. But, as a new review published in the journal Trends in Immunology Thursday argues, it seems to interact with the bag of organs that makes up our digestive system in complex and important ways, fighting disease and fine-tuning how the system works to keep us in fighting shape. Read More

CATEGORIZED UNDER: Health & Medicine, top posts

Retreating Ice Sheet Spurred Massive Methane Blowouts on the Seafloor

By Carl Engelking | June 1, 2017 1:00 pm
andreassen4HR

Methane still seeps from these craters on the Barents Sea floor, formed some 12,000 years ago when pent-up methane burst from sediment. (Illustration Credit: Andreia Plaza Faverola/CAGE)

A massive reserve of methane — a greenhouse gas more potent than carbon dioxide — is trapped deep within the seafloor.

In northern latitudes, thick ice sheets act as a lid sequestering gases at the right temperature and pressure. But when that ice melts, it’s akin to popping a cork on a pressurized bottle of champagne, rapidly releasing large volumes of the pent-up gas.

For proof that warmer conditions can spur violent belches, a team of scientists based in Norway looked to the Barents Sea, where high-resolution bathymetry — water depth measurements — revealed a seafloor pockmarked with giant craters, some more than a half-mile wide and nearly 100 feet deep. In a study published this week in Science, the researchers say methane gas blowouts formed these scars some 12,000 years ago after a major glacial retreat in the Arctic.

As thawing continues at Earth’s poles, what happened here long ago may be a harbinger of what’s to come.

Under Pressure

At the seafloor, methane exists as a hydrate, an icy mixture of gas and water that is stable within a narrow range of pressures and temperatures. Methane hydrates represent a vast store of untapped energy, though they aren’t currently being exploited for production.

Roughly 23,000 years ago, glaciers in the Barents Sea sat atop the sedimentary bedrock and provided pressure that kept chunks of methane hydrate at equilibrium.

craters

The swathe of the Barents Sea seafloor researchers studied, roughly 270 square miles, contains 100 sizable craters. (Illustration Credit: K. Andreassen/CAGE)

But the ice melted over thousands of years, reducing the glaciers’ stabilizing pressure. This caused chunks of methane hydrate to melt and allowed gases from deeper within the bedrock to bubble up, forcing seafloor sediments upward. Eventually, this formed dome-shaped mounds bloated with gases, called pingos. But they wouldn’t last very long.

Decomposing methane hydrates and bubbling gases carved channels in the pingos and weakened their structural integrity. Eventually, the pingos collapsed, quickly expelling large volumes of methane and forming the craters that scientists observed in their study.

“These mounds were over-pressured for thousands of years, and then the lid came off. They just collapsed releasing methane into the water column” says Karin Andreassen, lead author of the study and professor at the Centre for Arctic Gas Hydrate, Environment and Climate.

An Ice Sheet Harbinger?

Still today, methane steadily seeps from some 600 gas flares scattered around the field of craters researchers studied. Throughout the world’s oceans, much of the gas that seeps from flares never reaches the atmosphere; instead, methane often dissolves in the ocean, or is converted to carbon dioxide by microbes in the sediments or water column.

However, Andreassen says levels of gas trickling from these flares doesn’t compare to the massive volume of methane that can burst into the ocean following a major blowout. Still, it’s unclear if such a voluminous release of methane would in any way affect levels of greenhouse gases in the atmosphere. In February, the U.S. Geological Survey and the University of Rochester concluded that the breakdown of gas hydrates on the seafloor is unlikely to lead to a major uptick in levels of methane in the atmosphere.

siberian-crater

One of the many mysterious craters in Siberia. (Credit: Yamal Governor’s Press Office)

Andreassen and colleagues say their work simply provides a conceptual model for a thaw-blowout cycle, and could serve as a framework to forecast what will happen in years to come in another period of glacial retreat.

Interestingly, a similar process might be playing out on land in Siberia’s Yamal and Gydan peninsulas. There, scientists say they have discovered thousands of pingos on land swollen with methane gas, according to The Siberian Times. It’s believed that Siberia’s mysterious craters form when these pingos blow.

It’s quite clear that Earth belches from time to time, but how these gases ultimately affect the atmosphere, and in turn climate, remains a lingering question.

CATEGORIZED UNDER: Environment, top posts

3rd Gravitational Wave Detection Is About Much More Than Black Holes

By Eric Betz | June 1, 2017 10:00 am
More than a year after detecting the first confirmed gravitational waves, researchers were busy at the Laser Interferometer Gravitational-wave Observatory (LIGO) in Livingston, La., upgrading the massive instrument. (LIGO Lab)

More than a year after detecting the first confirmed gravitational waves, researchers were busy at the Laser Interferometer Gravitational-wave Observatory (LIGO) in Livingston, La., upgrading the massive instrument. (LIGO lab)

Our sun was still dim. Waves crashed on martian beaches. Life was emerging on Earth.

That’s when the ghosts of two dead stars — black holes dozens of times more massive than our sun — merged in a far-off corner of the universe. In their final moments, these binary black holes were circling each other hundreds of times per second, as each one spun at 10 times that rate. Read More

CATEGORIZED UNDER: Space & Physics, top posts

X-ray Blast Produces a ‘Molecular Black Hole’

By Nathaniel Scharping | May 31, 2017 1:53 pm
The LCLS Coherent X-ray Imaging Experimental Station. (Credit: Nathan Taylor/SLAC)

The LCLS Coherent X-ray Imaging Experimental Station. (Credit: Nathan Taylor/SLAC)

When researchers want to take pictures of very small things, like individual molecules, they have to get creative.

When scales shrink to seemingly imperceivable levels, images must be captured using indirect techniques that record how the subject being photographed interacts with its environment. One way to do this is by observing how a beam of particles disperses around the object. Working backward, researchers can then infer what the object in question looks like. Read More

CATEGORIZED UNDER: Space & Physics, top posts
MORE ABOUT: physics

Tree-Climbing Goats Keep the ‘Desert Gold’ Growing

By Mark Barna | May 31, 2017 11:42 am
tree-climbing-goats

Goats grazing on an argan tree in southwestern Morocco. In the fruiting season, many clean argan nuts are spat out by the goats while chewing their cud. (Credit: H. Garrido/EBD-CSIC)

What do goats and squirrels have in common?

They both climb trees, of course. While squirrels live amongst the branches, goats, or at least those in arid regions, climb them for dinner. And that’s good for the goats, and the trees.

Scientists have discovered that the domesticated goats in southern Morocco benefit the argan trees, Argania spinosa, by spitting out the seeds of the fruits they eat, which helps in seed dispersal. Argan trees play an important role in southern Morocco acting as a barrier for the Sahara Desert, and providing locals with wood, food, medicine and other materials. Argan oil, sometimes called “desert gold,” has also emerged as an international luxury commodity, prized for its supposed anti-aging and conditioning properties for hair and skin.  Read More

CATEGORIZED UNDER: Living World, top posts
MORE ABOUT: animals, plants
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