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Sat, 27 May 2017
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Cloud Lightning

What lightning does to rock quantified

© Reto Gieré
The study examined a rock fulgurite -- a thin layer of glass that forms when lightning strikes a rock's surface. The sample was collected from northern Italy's Mount Mottarone.
Benjamin Franklin, founder of the University of Pennsylvania, is believed to have experimented with lightning's powerful properties using a kite and key, likely coming close to electrocuting himself in the process. In a new set of experiments at Penn, researchers have probed the power of lightning in a less risky but much more technologically advanced fashion.

Chiara Elmi, a postdoctoral researcher in Penn's Department of Earth and Environmental Science in the School of Arts & Sciences, led the work, which used a suite of techniques to examine a fulgurite, a thin layer of glass that forms on the surface of rock when lightning hits it. Among other findings, the study discovered that, based on the crystalline material in the sample, the minimum temperature at which the fulgurite formed was roughly 1,700 degrees Celsius.

"People have been using morphological and chemical approaches to study rock fulgurites, but this was the first time a rock fulgurite was classified from a mineralogical point of view," Elmi said. "I was able to adapt an approach that I've used before to study the effects of meteorite impact in rocks and sediments to analyze a tiny amount of material in order to understand the phase transitions that occur when a lightning hits a rock."

Solar Flares

NASA footage captures sun shooting giant strands of plasma (VIDEO)

© NASA
The strands were several times the size of Earth.
Giant strands of plasma several times the size of earth danced on the surface of the sun in a spectacular solar show. The beautiful display was captured by a NASA camera capable of filming the intense light emitted by the star.

The 40-second video consists of a series of images captured over a 22-hour period between May 2 and 3. Magnetic forces pulled at the strands, turning them into twisting lines that stretched across the surface of the sun.

NASA's Solar Dynamics Observatory used a camera which isolates ultraviolet light to capture the mesmerizing show. Despite being several times the size of the earth, according to NASA, the strands are not expected to cause any havoc elsewhere in the solar system.


Telescope

Stunning! Hubble image captures hundreds of galaxies 6 billion light-years away

© NASA, ESA/Hubble, HST Frontier F
Abell 370 is one of the first galaxy clusters in which astronomers observed gravitational lensing, the warping of space-time by the cluster’s gravitational field that distorts the light from galaxies far behind it. Arcs and streaks in the picture are the stretched images of background galaxies.
In a breathtaking image of hundreds of galaxies, the Hubble Space Telescope provides an incredible display of a phenomenon known as gravitational lensing.

The telescope, run jointly by NASA and the European Space Agency, imaged a region six billion light-years away containing the galaxy cluster Abell 370.

Gravitational lensing, first proposed by physicist Albert Einstein in his general theory of relativity, warps space-time, bending light. In the case of this image, galaxies beyond the cluster spread out along multiple paths and appear in a few locations.

The longest streak in the image is the most dramatic display of lensing: there are four separate images of the single galaxy as the stretches and bends in an arc. In fact, all the arcs in this image are galaxies being bent through gravitational lensing.

Archaeology

Homo naledi, a newly added species to human family tree may have lived alongside our early ancestors

© Mark Thiessen
This reconstruction of Homo naledi by paleoartist John Gurche was crafted from skull remains from the Rising Star cave system's Dinaledi and Lesedi Chambers. H. naledi had primitive skeletal features, but the face, skull, and teeth show enough modern features to justify its placement in the genus Homo.
A year and a half after adding a puzzling new member to the human family tree, a team of researchers working in South Africa have offered an additional twist: the species is far younger than its bizarrely primitive body would suggest, and may have shared the landscape with early Homo sapiens.

First discovered in 2013 by two cavers exploring the Rising Star cave system near Johannesburg, a stunning trove of hominin remains—the single richest fossil site of its kind ever found in Africa—revealed a tiny-brained species with shoulders and a torso like an ape's, but with some unshakably humanlike features as well. The mosaic's name: Homo naledi, after the Sesotho word for "star."

Now, the species's star shines that much brighter. In papers published Tuesday in eLife, the team—led by University of the Witwatersrand (Wits) paleoanthropologist Lee Berger—provides an age range for the remains first reported in 2015: between 236,000 and 335,000 years old. The team also describes a second chamber within Rising Star that contains yet-undated H. naledi remains.

Eggs Fried

Turning chicken poop and weeds into biofuel

© Subversify Magazine
"Say what?"
Chicken is a favorite, inexpensive meat across the globe. But the bird's popularity results in a lot of waste that can pollute soil and water. One strategy for dealing with poultry poop is to turn it into biofuel, and now scientists have developed a way to do this by mixing the waste with another environmental scourge, an invasive weed that is affecting agriculture in Africa. They report their approach in ACS' journal Energy & Fuels.

Poultry sludge is sometimes turned into fertilizer, but recent trends in industrialized chicken farming have led to an increase in waste mismanagement and negative environmental impacts, according to the United Nations Food and Agriculture Organization. Droppings can contain nutrients, hormones, antibiotics and heavy metals and can wash into the soil and surface water. To deal with this problem, scientists have been working on ways to convert the waste into fuel. But alone, poultry droppings don't transform well into biogas, so it's mixed with plant materials such as switch grass.

Samuel O. Dahunsi, Solomon U. Oranusi and colleagues wanted to see if they could combine the chicken waste with Tithonia diversifolia (Mexican sunflower), which was introduced to Africa as an ornamental plant decades ago and has become a major weed threatening agricultural production on the continent.

The researchers developed a process to pre-treat chicken droppings, and then have anaerobic microbes digest the waste and Mexican sunflowers together. Eight kilograms of poultry waste and sunflowers produced more than 3 kg of biogas -- more than enough fuel to drive the reaction and have some leftover for other uses such as powering a generator. Also, the researchers say that the residual solids from the process could be applied as fertilizer or soil conditioner.

Attention

Sound advice: Human noise pervasive even in US protected areas, threatens endangered species

© US National Park Service
An acoustic recording station at Alcatraz Island in San Francisco Bay, Golden Gate National Park, California.
Protected areas in the United States, representing 14 percent of the land mass, provide places for respite, recreation, and natural resource conservation. However, noise pollution poses novel threats to these protected areas, according to a first-of-its-kind study from scientists at Colorado State University and the U.S. National Park Service.

Researchers found that noise pollution was twice as high as background sound levels in a majority of U.S. protected areas, and caused a ten-fold or greater increase in noise pollution in 21 percent of protected areas.

Comment: "Although plants can't hear..." Plants do respond to vibration, which is the main component of sound. One might be able to make a case that noise directly, rather than indirectly, affects plants.
...plants can discern the sound of predators through tiny vibrations of their leaves — and beef up their defenses in response. ... When pure tones are played, some experiments have seen changes in plant growth, germination or gene expression. For instance, one recent study showed that young roots of corn will grow toward an auditory source playing continuous tones and even responded better to certain frequencies. ... Although it has not been proved, the suspicion is that plants can perceive sound through proteins that respond to pressure found within their cell membranes. Sound waves cause their leaves to vibrate ever so slightly, causing the plant to respond accordingly.



Life Preserver

Icelandic babies who can stand at four months make science headlines

© Iceland Monitor/ Eva Björk Ægisdóttir
A baby at a swimming class in Iceland. This class is at Ungbarnasund Erlu in Reykjavik.
Results of research conducted by Icelandic professor of neuropsychology, Hermundur Sigmundsson, have been published in a respected science magazine called Frontiers of Psychology and have gained much attention. This was reported by today's Morgunblaðið.

According to his research, children as young as four months old can stand by themselves, if they receive the right stimulation and exercise.

Robot

Terminator robots - The military is using human brain waves to teach robots how to shoot

© NASA
A 2009 photo from the he Human Engineering Methods (HEM) Research Lab.
Modern sensors can see farther than humans. Electronic circuits can shoot faster than nerves and muscles can pull a trigger. Humans still outperform armed robots in knowing what to shoot at — but new research funded in part by the Army may soon narrow that gap.

Researchers from DCS Corp and the Army Research Lab fed datasets of human brain waves into a neural network — a type of artificial intelligence — which learned to recognize when a human is making a targeting decision. They presented their paper on it at the annual Intelligent User Interface conference in Cyprus in March.

Why is this a big deal? Machine learning relies on highly structured data, numbers in rows that software can read. But identifying a target in the chaotic real world is incredibly difficult for computers. The human brain does it easily, structuring data in the form of memories, but not in a language machines can understand. It's a problem that the military has been grappling with for years.

"We often talk about deep learning. The challenge there for the military is that that involves huge datasets and a well-defined problem," Thomas Russell, the chief scientist for the Army, said at a recent National Defense Industrial Association event. "Like Google just solved the Go game problem."

Top Secret

Newest secret US spacecraft returns to Earth after over 700 days in orbit

© AP Photo/ US Air Force
After over 2 years in space, advanced US re-entry X-37B Orbital Test Vehicle spacecraft successfully landed at NASA's Kennedy Space Center.

This was the fourth flight of this vehicle. Boeing started the secret X-37B Orbital Test Vehicle project under NASA's aegis in 1999. Originally, the reusable X-37 was intended to repair satellites in orbit. However, in 2004 the program was classified and handed over to the US Air Force.

According to the US Air Force, the X-37B Orbital Test Vehicle is "the newest and most advanced re-entry spacecraft."

Attention

Study: Alarming decrease in oceans' dissolved oxygen level

© Georgia Tech
Global map of the linear trend of dissolved oxygen at the depth of 100 meters.
A new analysis of decades of data on oceans across the globe has revealed that the amount of dissolved oxygen contained in the water - an important measure of ocean health - has been declining for more than 20 years.

Researchers at Georgia Institute of Technology looked at a historic dataset of ocean information stretching back more than 50 years and searched for long term trends and patterns. They found that oxygen levels started dropping in the 1980s as ocean temperatures began to climb.

"The oxygen in oceans has dynamic properties, and its concentration can change with natural climate variability," said Taka Ito, an associate professor in Georgia Tech's School of Earth and Atmospheric Sciences who led the research. "The important aspect of our result is that the rate of global oxygen loss appears to be exceeding the level of nature's random variability."

The study, which was published April in Geophysical Research Letters, was sponsored by the National Science Foundation and the National Oceanic and Atmospheric Administration. The team included researchers from the National Center for Atmospheric Research, the University of Washington-Seattle, and Hokkaido University in Japan.

Falling oxygen levels in water have the potential to impact the habitat of marine organisms worldwide and in recent years led to more frequent "hypoxic events" that killed or displaced populations of fish, crabs and many other organisms.