Oct 3, 2015

New 'Gilgamesh' Verse is Epic

A serendipitous deal between a history museum and a smuggler has provided new insight into one of the most famous stories ever told: “The Epic of Gilgamesh.”

The new finding, a clay tablet, reveals a previously unknown “chapter” of the epic poem from ancient Mesopotamia. This new section brings both noise and color to a forest for the gods that was thought to be a quiet place in the work of literature. The newfound verse also reveals details about the inner conflict the poem’s heroes endured.

In 2011, the Sulaymaniyah Museum in Slemani, in the Kurdistan region of Iraq, purchased a set of 80 to 90 clay tablets from a known smuggler. The museum has been engaging in these backroom dealings as a way to regain valuable artifacts that disappeared from Iraqi historical sites and museums since the start of the American-led invasion of that country, according to the online nonprofit publication Ancient History Et Cetera.

Among the various tablets purchased, one stood out to Farouk Al-Rawi, a professor in the Department of Languages and Cultures of the Near and Middle East at the School of Oriental and African Studies (SOAS) at the University of London. The large block of clay, etched with cuneiform writing, was still caked in mud when Al-Rawi advised the Sulaymaniyah Museum to purchase artifact for the agreed upon $800. [In Photos: See the Treasures of Mesopotamia]

With the help of Andrew George, associate dean of languages and culture at SOAS and translator of “The Epic of Gilgamesh: A New Translation” (Penguin Classics, 2000), Al-Rawi translated the tablet in just five days. The clay artifact could date as far back to the old-Babylonian period (2003-1595 B.C.), according to the Sulaymaniyah Museum. However, Al-Rawi and George said they believe it’s a bit younger and was inscribed in the neo-Babylonian period (626-539 B.C.).

Al-Rawi and George soon discovered that the stolen tablet told a familiar story: the story of Gilgamesh, the protagonist of the ancient Babylonian tale, “The Epic of Gilgamesh,” which is widely regarded as the first-ever epic poem and the first great work of literature ever created. Because of the time period when the story was written, the tale was likely inscribed on “tablets,” with each tablet telling a different part of the story (kind of like modern chapters or verses).

What Al-Rawi and George translated is a formerly unknown portion of the fifth tablet, which tells the story of Gilgamesh, king of Uruk, and Enkidu (the wild man created by the gods to keep Gilgamesh in line) as they travel to the Cedar Forest (home of the gods) to defeat the ogre Humbaba.

The new tablet adds 20 previously unknown lines to the epic story, filling in some of the details about how the forest looked and sounded.

“The new tablet continues where other sources break off, and we learn that the Cedar Forest is no place of serene and quiet glades. It is full of noisy birds and cicadas, and monkeys scream and yell in the trees,” George told Live Science in an email.

Read more at Discovery News

Angry Little Stars Could Produce Life-Friendly Exoplanets

Red dwarf stars may be able to support habitable exoplanets after all — through complex tidal interactions between star and planet, global magnetic fields could evolve, protecting hypothetical life forms from the red dwarfs’ ferocious nature.

Once identified as the perfect place to search for habitable exoplanets, in recent years, the life-giving reputation of red dwarf stars has taken a downturn. Sure, red dwarfs are abundant in our galaxy and we’ve spotted many with planetary systems, but the environment surrounding these tiny stars are generally considered to be a bad place for alien life to set up home.

For starters, red dwarfs are much smaller and therefore dimmer (and cooler) than our sun, so the distance a hypothetical “Earth-like” planet would need to orbit the star is much closer than the distance at which the Earth orbits the sun. The “habitable zone” — the region surrounding a star that isn’t too hot nor too cold for water to persist in a liquid state on that planet’s surface — is more compact around red dwarfs, creating a host of problems.

Although small, many red dwarfs observed are known as “flare stars” — basically angry little stars that generate powerful flares, drenching any nearby planets in powerful doses of radiation. These savage stellar storms, including powerful stellar winds, will likely sterilize any habitable zone planet, ensuring they remain uninhabitable (for biology as we know it in any case). In addition to the horrible stellar weather, planets orbiting within a red dwarf’s habitable zone will likely become “tidally locked” with the star; one hemisphere will always be sun-facing, whereas the far side will be in perpetual darkness.

But in new research by University of Washington scientists published in the journal Astrobiology, a planet in a compact orbit around a red dwarf star could receive a gravitational boost that could act as a planetary immune system of sorts, potentially shielding the worst radiation from sterilizing nearby worlds. This mechanism would put red dwarfs back in the life-hunting arena.

It was generally thought that tidally-locked planets were devoid of planetary magnetic fields, like the magnetosphere that surround Earth. But this may not be the case.

While orbiting a red dwarf star, a potentially habitable planet will likely become locked, resigning one hemisphere to an eternity of perpetual light. The close proximity to the star will also result in tidal heating in the planet’s mantle — during its orbit, the star’s gravitational field will periodically squash the world, driving a dynamo of heating. Much like Jupiter’s hellish moon Io, where tidal heating from Jupiter’s tides drive the most violent examples of volcanoes in the solar system, these worlds would experience tidal heating, just on a less extreme scale.

This tidal heating may not sound particularly life-friendly either, but it turns out that planets that undergo this form of heating are very good at dissipating heat from their cores. As the cores of these planets cool, the conditions may be ripe for the creation of global magnetic fields.

Read more at Discovery News

Oct 2, 2015

Woolly Mammoth Found by Michigan Farmers

Two farmers in Lima Township, Mich. stumbled upon the find of their lives while digging a drainage ditch. About 8 feet down, the Detroit Free Press reports, they struck bone and realized something large was buried in their midst.

Soon University of Michigan researchers were on the scene, and after a more extensive excavation they determined the two farmers had found an adult woolly mammoth skeleton.

Scientists at the site said it was among the most complete woolly mammoth skeletons ever unearthed in Michigan.

Found in the dig were the head, tusks, ribs, and a set of vertebrae. A university paleontologist told the publication it was likely killed by humans some 10,000 to 15,000 years ago.

Its killing by humans explains parts of the mammoth that were missing -- they were likely eaten, the expert said. The creature was between 40 and 50 years old.

From Discovery News

Asteroid, Volcanoes Double Whammy Doomed Dinosaurs

A massive asteroid strike 66 million years ago triggered a string of potent volcanic eruptions that spelled doom for the dinosaurs, US researchers said Thursday.

Just what led to the demise of the dinosaurs is often debated among scientists, and the latest findings in the journal Science suggest that both events are to blame, not one or the other.

Scientists studied the Deccan Traps lava flows in India, and their most accurate dating yet shows that the volcanoes doubled their output in close proximity to the asteroid or comet strike that set off the last mass extinction on Earth.

"Based on our dating of the lavas, we can be pretty certain that the volcanism and the impact occurred within 50,000 years of the extinction, so it becomes somewhat artificial to distinguish between them as killing mechanisms: both phenomena were clearly at work at the same time," said lead researcher Paul Renne, a University of California, Berkeley professor of earth and planetary science.

"It is going to be basically impossible to ascribe actual atmospheric effects to one or the other. They both happened at the same time."

Together, the asteroid impact and the volcanic eruptions would have "blanketed the planet with dust and noxious fumes, drastically changing the climate and sending many species to an early grave," said a statement from UC Berkeley.

The impact of the asteroid changed the underground plumbing in the volcanoes, making some magma chambers larger so they spouted more lava when they erupted.

It would take Earth and its land and ocean life about 500,000 years to emerge from the devastation.

Read more at Discovery News

California Once Had a 2,000-Year-Long Dry Spell

California’s current lengthy drought is really punishing the state’s residents, who’ve been compelled by government restrictions to reduce their water use by nearly a third in a desperate effort to conserve the dwindling amount of H2O left in the state’s reservoirs.

But as a recently-published study in the journal Quaternary Science Reviews reveals, the state once experienced a much longer dry spell — a series of mega-droughts as bad as the one today, strung together over a 2,000-year-period.

Fortunately, though, they occurred at a time — 25,500 to 27,500 years ago — when there weren’t any Californians around yet to complain about not being able to water their lawns.

Paleoecologists Linda Heusser and Jonathan Nichols, of Lamont-Doherty Earth Observatory, did a high-resolution analysis of pollen levels in a sediment core drilled from the bottom of Lake Elsinore, which is to the east of the Santa Ana Mountains near Los Angeles. That method provides the first detailed continuous record of ecological changes in coastal southern California from 32,000 to 9,000 years ago, with shifts measurable on a scale of decades rather than centuries.

Pollen records are unique in that we can capture the vegetation distribution,” Heusser said in a press release. “There are no other records of vegetation that extend through this time. The best we had been able to do before for this time frame was stalagmites inferring precipitation in a cave in New Mexico.”

The pollen count at various levels of the sediment showed that pine trees and juniper, which dominated the region’s ecosystem until about 27,500 years ago, were replaced by dryland herbs, shrubs and chaparral for about 2,000 years. Then, the pine trees and junipers began to return.

The researchers also found that changes in the pollen record also correlate with analysis of sediment cores from the Pacific Ocean just off Santa Barbara, which show that that the ocean was warmer during the periods that droughts occurred. That suggests that ocean conditions may have been the driver of the mega droughts.

From Discovery News

This Ferocious Arachnid Is Death Wrapped in Mystery

"Oh God what is that thing!?"
You may have come across a 2004 image of an American soldier in Iraq holding two huge “camel spiders,” one of which had clamped its jaws on the other. Huge. As in, they alone were reason enough to get out of Iraq. Now, they aren’t really spiders, and through a trick of perspective (they’re just close to the camera) they look way bigger than they really are. Don’t get me wrong, the strange, hairy camel spiders do grow to six inches long—not too shabby. But size is far from the most fascinating thing about these beasts.

Camel spiders are arachnids like true spiders, but they belong to a different order, solifugae. (Depending on who you ask, camel spiders are so-called because some species have humps on their backs or because of the myth that they eat camel stomachs.) Also called wind scorpions for their incredible speed (and hey, why not confuse them for another kind of arachnid while we’re at it), these things have jaws like you wouldn’t believe—dextrous chompers that can be a third of their body length and that shred prey as big as rodents.

With these beasts comes lore. In addition to the camel stomach stuff, legend says that as camel spiders scream as they speed around the desert, that they can leap incredible distances, and that they’ll even attack humans, injecting them with a sleepy-time venom and gnawing on the victims as they slumber.

None of these things are any truer-to-life than the behaviors of camel spiders depicted in the 2011 horror movie Camel Spiders, a lazily titled film if I’ve ever heard one. But it’s true that science still knows little about the camel spider, for although they tally some 1,000 species the world over, they’re rare and almost unstudied. “For 10, maybe 15 years almost now, I’ve been doing research in the Caribbean, and I’ve spent a combined maybe four years in the field,” says arachnologist Lauren Esposito of the California Academy of Sciences. “I’ve found two. Ever.”

Why the camel spiders are so rare, Esposito can’t say. It could be that their populations are just low (they do tend to be more common in the Middle East, as opposed to the Caribbean). Being nocturnal doesn’t help humans find them either. And the fact that they burn rubber certainly doesn’t help. “If you sit under a light trap,” Esposito says, “a lot of times they’re attracted to the movement of the moths that are attracted to the light. And they’ll just come out of nowhere and grab something and run off again. They’re super fast.”

If a creature is a reasonable size compared to the camel spider, chances are the predator can overwhelm it. Larger species of camel spider go after rodents and lizards. But interestingly for a speedy predator, camel spiders “probably have really poor eyesight,” says Esposito, considering how tiny their eyes are, “and mostly sense through vibrations that they pick up in the hairs all over their body.”

As for those mouthparts: In arachnids like this they’re known as chelicerae, like the formidable fangs you find on tarantulas. But tarantulas ain’t got nothing on the camel spider’s chompers. A camel spider has a pair of chelicerae like other arachnids, but each pair is itself a pair of scissor-like, serrated blades, powered by massive muscles. Think of the creature as wielding two toothy beaks.

The camel spider’s jaws tear through everything from flesh to hard exoskeletons to the fragile human psyche.
And the camel spider’s jaws aren’t just powerful—they’re highly maneuverable. “So they can really open them up and move them almost omnidirectionally,” says Esposito. “They obviously have a lot more musculature associated with those mouthparts. So it’s almost like the mouth in Predator, where it opens up in four directions.”

While spiders and scorpions rely on venom to kill their prey, the camel spider doesn’t bother. They haven’t a drop of venom (much less a venom that can knock a human out cold, though their bites can be painful from the sheer trauma). Nor does the camel spider produce silk to trap its food. This is a minimalist hunter: nothing fancy. Just speed and teeth.

They prowl ecosystems the world over. The large desert-adapted varieties tend to have comb-like hairs on their legs that may help them shovel sand to dig burrows. “Their legs and feet become elongated,” Esposito says, “because they need to be higher up off of the substrate and have more surface ratio to stay on top of the sand, instead of sinking when they’re running.”

Regardless of geographical adaptations, what all camel spiders agree on is the freaky sex. In the sense that if you care to watch the video below, complete with inappropriate music, I’m going to explain what’s going on. That kind of freaky sex.

From the few complete courtships of camel spiders that scientists have observed, it seems that the males charge in and overpower the females. They hold on in part with sensory structures called pedipalps, which are tipped with suction cups, and “they basically bend the female in half and hold onto her and don’t let go,” Esposito says. “So they use their speed to run up quick and grab on and hold on for dear life.”

The problem is, the female may have mated with other males, who left their sperm packets in her oviduct. By gnawing on this oviduct, the male may be trying to remove his rivals’ sperm. “The way sperm works in the oviduct system is the last in is the first out,” Esposito says. “The female’s eggs are going to be fertilized by whoever the last one in was, so he’s trying to get rid of that.” He then uses his chelicerae to insert his own sperm packet.

Read more at Wired Science

Oct 1, 2015

New Zealand Fish Plucks Food Off Dry Land

An Auckland, New Zealand teacher and two students came across an unusual sight while surveying banded kokopus in a local stream. They saw one of them jump out of the water and quickly touch upon the river bank.

According to Auckland's North Shore Times the teacher, Kit Hustler, and his charges suspected it was a hunting tactic they'd just witnessed.

So the trio set out traps of larvae along the river bank and waited. Sure enough, nearly all of the kokopus they observed leaped from the water and successfully plucked the bait from the bank, diving back into the water with their snacks. (See video above.)

The banded kokopu are largely nocturnal and can only be found in New Zealand. They typically grow to about 8-10 inches long and can live for 9 years or more.

Hustler thinks the fish keeps an active watch on the shore, and this new behavior may help explain prior studies that showed unexpected contents in the fish's stomach, the North Shore Times noted.

The fish, it seems, has a wider food supply than previously thought, as well as an unexpected approach to obtaining it.

"It's quite unique for fish to jump out of the water," Hustler told the North Shore Times. "I don't know how many do but I'd say it's less than 20 globally."

From Discovery News

Mustached Bird Photographed for First Time, Then Killed

The first ever photographs of the elusive male moustached kingfisher were recently released by the American Museum of Natural History. They show a vibrant blue adult bird in apparent good health.

There is a sad footnote to the images, however, because researchers elected to kill the endangered bird in order to further study it.

Paul Sweet, collection manager for the museum’s Department of Ornithology, told Audubon that he and his colleagues assessed the state of the bird’s population and habitat, and concluded it was substantial and healthy enough to withstand the loss.

The suspenseful moments before the bird’s discovery and subsequent death are recorded in a field journal written by Chris Filardi, who is director of Pacific Programs at the museum’s Center for Biodiversity and Conservation.

He and his colleagues were in the remote moss jungle highlands of Guadalcanal in the Solomon Islands when they heard a distinctive call: “ko-ko-kokokokokokokokoko-kiew!”

They paused and scanned the forest. After time passed, “There in plain sight pumping its tail, crest alert, in full colors, was the moustached kingfisher,” Filardi wrote. “And then, like a ghost, it was gone.”

For days the researchers looked for the bird. They set fine nets into the forest canopy, hoping to capture the individual. After a blustery morning of cold winds and rain showers, they managed to capture the male moustached kingfisher.

“When I came upon the netted bird in the cool shadowy light of the forest I gasped aloud, ‘Oh my god, the kingfisher,’” Filardi recounted. “One of the most poorly known birds in the world was there, in front of me, like a creature of myth come to life.”

Photographs were taken of the bird. Frank Lambert, another member of the research team, also managed to record the bird’s distinctive call. The recording has not yet been released.

The moustached kingfisher is listed as endangered by the International Union for Conservation of Nature. It is estimated that there are only 250–1000 mature individuals left, but the bird’s elusiveness puts even those figures into question.

Read more at Discovery News

Seal Hints Alexander Great's Close Friend at Tomb

Three inscriptions might have revealed the identity of the individual originally buried in the mysterious mound complex that was opened in northern Greece last summer, Greek archaeologists announced on Wednesday.

During a conference in Thessaloniki, head archaeologist Katerina Peristeri said her team uncovered evidence that the Alexander the Great-era tomb in Amphipolis, east of Thessaloniki, was commissioned and financed by the Macedonian king in honor of his beloved friend and general Hephaestion.

Peristeri added that her team unearthed finds which were marked with the seal of Alexander’s architect Deinokrates, suggesting the tomb was likely designed by that architect.

Further evidence indicated the monument was constructed at the end of the 4th century B.C. by Antigonus I Monophthalmus (Antigonus the one-eyed), who became king of Macedonia in 306 B.C., 17 years after Alexander’s death.

“Chances are that this is a funerary heroon (hero worship shrine) dedicated to Hephaestion,” Peristeri said.

According to the Greek historian Plutarch (about 46 – 120 A.D.), when Hephaestion died suddenly in Ecbatana, Iran, a devastated Alexander asked his architect to erect shrines across the country to honor his friend.

“We do not know if Hephaestion is buried inside the tomb,” Peristeri added.

The discovery of the mysterious tomb created a national frenzy when in August 2014 Peristeri and her team broke through the entrance of the burial mound.

Dated to between 325 B.C. — two years before Alexander the Great’s death — and 300 B.C., the tomb is billed as the largest of its kind in the Greek world, measuring more than 1,600 feet in circumference. Sadly, the monument was thoroughly and repeatedly looted.

Nevertheless, for months archaeologists engaged in an extraordinary exploration that winded through huge decapitated sphinxes, walls guarded by colossal female statues, and floors decorated with stunning mosaics.

In January this year Peristeri’s team found bone fragments belonging to at least five individuals who were identified as being a woman, two men, a newborn baby and a cremated adult whose gender could not be verified. Forensic study and DNA analysis are still ongoing.

The three inscriptions, which Peristeri and her head architect Michalis Lefantzis believe were contracts for the construction of the massive burial, lay more than one mile outside the tomb, in an area where the Lion of Amphipolis, which once topped the monument, was found.

Featuring the monogram of Hephaestion, the inscriptions were decoded to read: “I, Antigonus received construction material for the erection of a monument in honor of Hephaestion.”

A Macedonian nobleman and a battlefield general in the army of Alexander, Hephaestion was Alexander’s closest friend since childhood. The two were tutored under Aristotle.

Although more than one historian has suggested that the handsome Hephaestion had a physical relationship with his emperor, no contemporary source states that Alexander and Hephaestion were lovers.

Yet, according to Guy MacLean Rogers, professor of history at Wellesley College and the author of “Alexander: The Ambiguity of Greatness,” modern sexual categories like homosexual, heterosexual, and bisexual did not exist at the time.

“In ancient Greece, acting upon a desire (sent by the god Eros) for another man or woman, simply did not lock any man or woman into a sexual camp,” Rogers wrote.

Whatever the nature of their relationship, when Hephaestion died in Ecbatana (modern Hamadan) in western Iran in October 324 B.C., Alexander mourned his loss by shaving his own hair, not eating for days, executing Hephaestion’s doctor, and commissioning an expensive funeral pyre.

Alexander himself would die eight months later, having built an empire that stretched from modern Greece to India.

Read more at Discovery News

3 Civil War Cannons Pulled from River

A community in the southern United States reclaimed an important part of its history Tuesday (Sept. 29), when three Civil War-era cannons were pulled up from the Pee Dee River in Florence, South Carolina.

The now-rusty relics once adorned the deck of a Confederate warship, the CSS Pedee, which was built in a shipyard just east of Florence, South Carolina. The cannons, as well as the remains of the ill-fated ship, have been at the bottom of the river for 150 years.

Heavy machinery was needed to lift the huge cast-iron cannons out of the water, according to WMBF News, which reported that the heaviest of the weapons weighed a whopping 15,000 lbs. (6,800 kilograms). Divers attached the cannons to the arm of a giant front-end loader with ropes, and it took about 30 minutes to pluck each one from the river, WMBF News reported.

Aside from being coated in mud and muck, the recovered cannons were in surprisingly good condition and are more or less “ready to rock and roll,” said Jonathan Leader, South Carolina’s state archaeologist, who helped lead efforts to locate the remains of the sunken CSS Pedee. Receding waters left the third cannon (a 7-inch Brooke rifle) exposed, and the gun is a bit corroded as a result, he said.

The recovery of the cannons marks a milestone for Leader and his colleagues at the South Carolina Institute of Archaeology and Anthropology at the University of South Carolina. Between 2009 and 2012, the state archaeologist worked with several institutions, nonprofits and local volunteer organizations to find parts of the ship, including the cannons, and figure out how to get them out of the water. The task of plucking the guns from the river was facilitated by a grant from the Drs. Bruce and Lee Foundation in Florence.

Archaeologists also located the site of the Mars Bluff Navy Yard, where Confederate troops and local volunteers built the CSS Pedee and several smaller boats during the Civil War. But the discovery of the CSS Pedee’s cannons is particularly special, Leader told Live Science.

Typically, victors scour the battlefield after a fight, and anything useful is hauled off and used again in future battles, Leader said. After the Civil War, cannons and other weapons were gathered and moved to various federal depots. Piled together and taken from their original context, objects like cannons became anonymous, Leader said, losing what he called their “important connections to battlefields, military actions and communities.”

But that is not the case for the CSS Pedee’s cannons. Thanks to historical records and oral histories from locals, a lot is known about how and where these cannons were used and who operated them, Leader said. The last time the Confederate warship’s cannons were fired, they were pointed at Union Gen. William T. Sherman and his troops, who were advancing into North Carolina, he said.

Fearing the ship would fall into enemy hands, Confederate soldiers threw the cannons overboard before they “scuttled,” or deliberately sank the CSS Pedee. The dredged-up weapons serve as a direct link to that moment in history, Leader said, noting that reclaiming the cannons felt like a “handshake over the ages.”

But the rusty old weapons aren’t just important to archaeologists like Leader; they’re also meaningful to the people of South Carolina, many of whom had ancestors that fought in the Civil War and who may have helped construct the USS Pedee at the Mars Bluff Navy Yard.

“This was an early version of a modern dreadnaught,” Leader said. “It had the most advanced guns of the day mounted on its decks … It was a serious threat. And it was built by the locals.”

Read more at Discovery News

Sep 30, 2015

Earth-like planets around small stars likely have protective magnetic fields, aiding chance for life

Earth-like planets orbiting close to small stars probably have magnetic fields that protect them from stellar radiation and help maintain surface conditions that could be conducive to life, according to research from astronomers at the University of Washington.

A planet's magnetic field emanates from its core and is thought to deflect the charged particles of the stellar wind, protecting the atmosphere from being lost to space. Magnetic fields, born from the cooling of a planet's interior, could also protect life on the surface from harmful radiation, as Earth's magnetic field protects us.

Low-mass stars are among the most common in the universe. Planets orbiting near such stars are easier for astronomers to target for study because when they transit, or pass in front of, their host star, they block a larger fraction of the light than if they transited a more massive star. But because such a star is small and dim, its habitable zone -- where an orbiting planet gets the heat necessary to maintain life-friendly liquid water on the surface -- also lies relatively close in.

And a planet so close to its star is subject to the star's powerful gravitational pull, which could cause it to become tidally locked, with the same side forever facing its host star, as the moon is with Earth. That same gravitational tug from the star also creates tidally generated heat inside the planet, or tidal heating. Tidal heating is responsible for driving the most volcanically active body in our solar system, Jupiter's moon Io.

In a paper published Sept. 22 in the journal Astrobiology, lead author Peter Driscoll sought to determine the fate of such worlds across time: "The question I wanted to ask is, around these small stars, where people are going to look for planets, are these planets going to be roasted by gravitational tides?" He was curious, too, about the effect of tidal heating on magnetic fields across long periods of time.

The research combined models of orbital interactions and heating by Rory Barnes, assistant professor of astronomy, with those of thermal evolution of planetary interiors done by Driscoll, who began this work as a UW postdoctoral fellow and is now a geophysicist at the Carnegie Institution for Science in Washington, D.C.

Their simulations ranged from one stellar mass -- stars the size of our sun -- down to about one-tenth of that size. By merging their models, they were able, Barnes said, "to produce a more realistic picture of what is happening inside these planets."

Barnes said there has been a general feeling in the astronomical community that tidally locked planets are unlikely to have protective magnetic fields "and therefore are completely at the mercy of their star." This research suggests that assumption false.

Far from being harmful to a planet's magnetic field, tidal heating can actually help it along -- and in doing so also help the chance for habitability.

This is because of the somewhat counterintuitive fact that the more tidal heating a planetary mantle experiences, the better it is at dissipating its heat, thereby cooling the core, which in turn helps create the magnetic field.

Barnes said that in computer simulations they were able to generate magnetic fields for the lifetimes of these planets, in most cases. "I was excited to see that tidal heating can actually save a planet in the sense that it allows cooling of the core. That's the dominant way to form magnetic fields."

And since small or low mass stars are particularly active early in their lives -- for the first few billion years or so -- "magnetic fields can exist precisely when life needs them the most."

Driscoll and Barnes also found through orbital calculations that the tidal heating process is more extreme for planets in the habitable zone around very small stars, or those less than half the mass of the sun.

Read more at Science Daily

Escaped Honeybees Swarm Oklahoma Patrol Car

Motorists along Interstate 35 in Gavin County, Okla. ended up stranded in a multi-mile backup. The reason? An overturned truck was carrying an unusual load: honeybees. Lots and lots of honeybees.

The video below documents what life was like for a county sheriff whose vehicle was swarmed by the newly freed insects.

"Millions, millions of bees. I couldn't give you a number, but millions," a brave motorist who rescued the bee-truck driver told KFOR.

Working through the swarm, which set upon several emergency vehicles, beekeepers dispatched to the scene were able to recapture a couple of hundred thousand bees, KFOR reported. The truck driver was treated at a local hospital and later released.

From Discovery News

1500-Year-Old Mosaic Map Found

A rare 1,500-year-old mosaic discovered in Israel that unusually depicts a map with streets and buildings will be revealed for the first time tomorrow.

Painstakingly restored, the mosaic measures about 3.5 meters (11.4 feet) by 3.5 meters and was found two years ago in an industrial park in the southern Israeli town of Kiryat Gat.

According to the Israel Antiquities Authority, it adorned the floor of a church dating to the Byzantine period. The church did not survive, but the mosaic was excavated and moved for restoration.

Intriguingly, the artwork shows buildings arranged along a main colonnaded street of a city. Buildings are portrayed in detail and in three dimensions, and have two–three stories, balconies and galleries, roof tiles and windows.

“The appearance of buildings on mosaic floors is a rare phenomenon in Israel,” the archaeologists involved in the excavation, Sa’ar Ganor and Rina Avner of the Israel Antiquities Authority, said in a statement.

A closer inspection revealed a Greek inscription alongside one of the buildings. It pointed to the place depicted in the mosaic: the settlement Chortaso, in Egypt.

“According to Christian tradition, the prophet Habakkuk was buried there. The appearance of this Egyptian city on the floor of the public building in Qiryat Gat might allude to the origin of the church’s congregation,” Ganor and Avner said.

Read more at Discovery News

Ancient Booty Discovered in Transylvania

Two large stashes of bronze weapons and jewelry, from the eighth century B.C., have been discovered in southern Transylvania, in Romania.

The hoards date back to a time before minted currency had been invented or writing had spread to this part of Europe.

Within the collections, which held 300 and 50 objects, respectively, the researchers discovered double axes, short swords and spears. They also found brooches, foot and arm bracelets, pendants, torques (a kind of neck ring), beads, and hairpins. (All the jewelry was made of bronze.) The researchers found parts of horse harnesses, as well.

“The majority of the objects are made of bronze, yet there are also weapons and tools made of iron,” wrote Corina Bors, a senior archaeologist with the National History Museum of Romania, in the summary of a presentation she gave recently at the European Association of Archaeologists annual meeting in Glasgow, Scotland.

The hoards were discovered in a small ravine, dotted with springs, on the southern edge of a prehistoric site now called Tartaria–Podu Tartariei vest, which spreads over an area of 25 acres (10 hectares). This site was first discovered in the spring of 2012 during archaeological investigations carried out before the construction of a motorway in the area.

Many other finds were made at the site, including offering pits containing broken pottery and a burial site containing several bodies.

Gift for the gods?

The archaeologists said they aren’t sure who deposited the hoards or for what purpose. In different parts of Europe, bronze hoards have been found in caves, springs, marshes and rivers, Bors said. “Such bronze hoards might be seen as votive depositions, or, in other words, gifts to the deities of that time,” Bors told Live Science.

A wealthy and powerful person, or persons, likely left the hoards that were discovered at Tartaria–Podu Tartariei vest. “It’s plausible to believe that this offering was made by somebody with high social status,” Bors said, adding that the person may have been “a warrior chieftain.”

It’s important that archaeologists, not amateurs, discovered the hidden stashes, as this allows for scientific excavations and conservation, Bors said. Archaeologists in Romania have never had an opportunity to scientifically excavate and examine a hoard of this age in the place where it was deposited in ancient times, Bors said.

Read more at Discovery News

NASA: We Need YOUR Help to Solve Ceres Mystery

Among the highest features seen by NASA's Dawn spacecraft on Ceres so far is a mountain about 4 miles (6 kilometers) high, which is roughly the elevation of Mount McKinley in Alaska. But how did it form? NASA, for now, has no idea.
Throwing open the doors to the hallowed halls of science, stumped researchers welcomed help from the public Wednesday in solving a number of nagging mysteries about dwarf planet Ceres.

NASA's space probe Dawn, which traveled seven-and-a-half years and some 4.9 billion kilometers (3 billion miles) to reach Ceres in March this year, is the first to orbit a dwarf planet.

The probe is seeking to learn more about the structure of Ceres, which circles the sun between Mars and Jupiter, in a bid to better understand the formation of Earth and other planets.

But many of the features of Ceres have left researchers scratching their heads -- including a 6 kilometer (4 mile) high protrusion they have dubbed "Lonely Mountain".

"We're having difficulty understanding what made that mountain and we have been getting many suggestions from the public," Dawn's principal investigator Christopher Russell told reporters at a space conference in Nantes, western France.

One fan of the probe sent Russell an email saying the mountain reminded him of some ice structures he had seen in the woods years earlier while living in the US state of Arkansas.

"These ice structures started just poking out (of the ground). Each one of them had a rock or something like that protecting the surface, keeping it cool," Russell said in describing the ice.

"Maybe our lonely mountain was some sort of ice construct," the scientist said, adding: "We're taking suggestions like this very seriously."

Russell said "many suggestions" have poured in from the public but did not provide an exact number.

First classified a planet, then an asteroid, then a "dwarf planet" with some traits of a moon -- the more scientists learn about Ceres, the weirder it becomes.

"We have absolutely no idea what that... is due to," Russell said as he pointed to a blue ring on a map of the planet.

Read more at Discovery News

Sep 29, 2015

Fossil Analysis Shows Extinct Bat's True Colors

For the first time, paleontologists have been able to analyze fossils and derive the colors of extinct mammals.

Virginia Tech and University of Bristol scientists analyzed microscopic structures in the fossils of two bats that lived 50 million years ago and determined what their coloring would have been in life -- a reddish-brown.

The researchers say the technique can be used on well preserved fossils up to 300 million years old. The finding, then, could help scientists figure out the real colors of a great many extinct species whose coloring has until now only been guessed at.

The structures the team studied in the bat fossils were once believed, in a long-running debate, to be fossilized bacteria. But the researchers say they are actually melanosomes, cell structures that hold melanin, the substance that brings color to skin, hair, feathers and eyes.

The study's senior author, University of Bristol paleontologist Jakob Vinther, has worked with fossil melanosomes since 2008, when he first described them from a fossilized feather, a discovery that led to the identity of colors in some dinosaurs. And now mammals are having their turn at a kind of color restoration.

Vinther and his colleagues found that different melanosome shapes indicate different colors. "Reddish melanosomes are shaped like little meatballs, while black melanosomes are shaped like little sausages," he explained in a press release.

"This means that this correlation of melanin color to shape is an ancient invention, which we can use to easily tell color from fossils by simply looking at the melanosome's shape," Vinther said.

The team also determined that fossil melanosomes are chemically distinct.

"We were able to see how melanin chemically changes over millions of years, establishing a really exciting new way of unlocking information previously inaccessible in fossils," Virginia Tech doctoral student Caitlin Colleary, the study's lead author, explained.

Learning about ancient animal colors is important, said Massachusetts Institute of Technology Earth Science Professor Roger Summons, who was not involved in the research. "For complex animal life, color is a factor in how individuals recognize and respond to others, determine friend or foe, and find mates," he said. "This research provides another thread to understand how ancient life evolved."

Read more at Discovery News

Black Death Bacteria Found on Frozen-in-Time Flea

A 20-million-year-old flea preserved in amber harbors the likely ancestor of bacteria that caused one of the world’s deadliest plagues, the Black Death, according to a new study.

Researchers believe the bacteria, described in the Journal of Medical Entomology, was an ancient strain of Yersinia pestis, which caused the bubonic plague, aka the Black Death. More than a third of Europe’s population — at least 30 million people — succumbed from the scourge in the 14th century.

Droplets of the bacteria were found on the flea’s proboscis (sucking mouthpart) and in the rectum of the flea, near its butt.

“Aside from physical characteristics of the fossil bacteria that are similar to plague bacteria, their location in the rectum of the flea is known to occur in modern plague bacteria,” author George Poinar, Jr., an entomology researcher in the College of Science at Oregon State University, said. “And in this fossil, the presence of similar bacteria in a dried droplet on the proboscis of the flea is consistent with the method of transmission of plague bacteria by modern fleas.”

The amber containing the flea was found in amber mines at what is now the Dominican Republic, between Puerto Plata and Santiago. Millions of years ago the area was a tropical forest.

Poinar, Jr., studied the size, shape and characteristics of the flea’s bacteria under extremely high magnification. All of its features are consistent with modern forms of the bubonic plague bacteria. Only Y. pestis exhibits unique rod and spherical shapes, which the flea’s bacteria displays as well.

Previously it was thought that fleas became disease vectors, causing illness in animals, around 20,000 years ago. Now scientists like Poinar, Jr., are rethinking that supposition.

Aside from the preserved-in-amber flea, there is evidence that past outbreaks of bubonic plague were caused from different strains, some of which are now extinct. In theory, the bacteria could have been evolving for millions of years.

While dinosaurs went extinct around 66 million years ago, long before this flea was alive, fossilized flea-like creatures have been found dating to the Dino Era. It’s long been theorized that a meteor strike coupled with volcanic activity did in the dinos, but perhaps disease played a factor too. Time will tell if evidence is found to support that possibility.

Read more at Discovery News

Glowing Sea Turtle Spotted off the Solomon Islands

A sea turtle in the Solomon Islands has set imaginations to "11" on the mind-blown dial. It's being hailed as the first documented reptile to glow by way of biofluorescence.

National Geographic has the details behind the spotting of a hawksbill sea turtle by one of its explorers -- marine biologist David Gruber, from City University of New York.

The turtle Gruber spotted and recorded was showing off bright green and red colors that gave it a neon glow. It was biofluorescing -- reflecting blue light and flashing it back out as another color. (Not to be confused with the bioluminescence some animals exhibit, where they essentially give off their own light from within or from things such as bacteria resting on them.)

Corals and other creatures of the deep biofluoresce, National Geographic notes, but a marine reptile doing it came as a complete surprise.

"I've been [studying turtles] for a long time and I don't think anyone's ever seen this," a hawksbill sea turtle expert told NatGeo.

Gruber followed the shiny turtle for a bit before letting it go on its way. He told NatGeo it was too soon to know how glowing helps this particular turtle, adding that the usual reasons tend to do with hunting, camouflage, or communication.

The researcher said that while the glowing turtle raises many questions -- how specifically it does it, why it does it, for example -- the critically endangered animals will be tough to study. Their populations have declined about 80 percent in the last 10 years, according to the International Union for Conservation of Nature's "red list" of endangered species.

From Discovery News

King Tut's Tomb Reveals Two Secret Chambers

A new examination of King Tut’s tomb has provided evidence of two hidden rooms, Egypt’s Antiquities minister Mamdouh Eldamaty announced on Monday.

According to Eldamaty, scratching and markings on both the northern and western walls are similar to those found by Howard Carter on the entrance gate of King Tut’s tomb. Carter discovered the treasure-packed burial in 1922.

“This indicates that the western and northern walls of Tutankhamun’s tomb could hide two burial chambers,” Eldamaty told Egypt’s English-language news site Ahram Online.

The investigation follows a similar claim by Nicholas Reeves, a British Egyptologist at the University of Arizona. Last month he published a paper arguing that high-resolution images of the tomb’s walls show “distinct linear traces” pointing to the presence of two still unexplored chambers.

Reeves speculated that one of such chambers contains the remains, and possibly the intact grave goods from queen Nefertiti, the wife of the “heretic” monotheistic pharaoh Akhenaten, Tutankhamun’s father.

He argued that a painting located behind King Tut’s sarcophagus has been wrongly interpreted. The painting shows Ay (who largely directed King Tut's reign and succeeded him) performing the Opening of the Mouth ritual on the boy king.

The figure labelled Tutankhamun would actually be Nefertiti. He noted that the lines at the corner of the figure’s mouth are a trademark in pictures of Nefertiti. On the other hand, the figure labelled Ay would be Tutankhamun, completing the death ritual for Nefertiti.

According to Reeves, the tomb of King Tut was not ready when he died unexpectedly at 19 in 1323 B.C. after having ruled a short reign of nine to 10 years. Thus he was buried in a rush in what was originally Nefertiti’s tomb, who died 10 years earlier.

Reeves told reporters the tomb’s examination revealed several unusual features, such as a contrast in the materials that cover different parts of the same wall and an extended ceiling which suggests King Tut’s tomb was originally a corridor.

“After our first examination of the walls we can do nothing more until we receive the all-clear from the radar device to confirm our findings,” Reeves told Ahram Online.

According to Eldamaty, it’s very likely there are hidden chambers in King Tut’s tomb. However, he disagrees with Reeves on the Nefertiti claim.

“The theory is a very good theory but it doesn’t mean it’s true. The best theories don’t always work,” he told reporters.

Read more at Discovery News

So Liquid Water Flows on Mars -- Now What?

The discovery of seasonal water flows on the surface of Mars could galvanize both the search for indigenous life as well plans for future human settlements, but don’t pack your bags quite yet.

For the immediate future, NASA’s Mars Reconnaissance Orbiter, which provided the legwork that led to Monday’s announcement, will continue to gather high-resolution images and chemical data from areas, known as recurring slope lineae, or RSL, that have been linked to recent briny water flows.

These dark, narrow streaks cut into cliff walls throughout the planet’s equator are unreachable by Curiosity and Opportunity, the two rovers now operating on Mars, and the Curiosity-class rover that is due to launch in 2020.

“Curiosity has gone up some pretty steep slopes, but some of these briny features are in tough terrain. It’d be trivial to an astronaut in a spacesuit to go up and investigate, but it’s very hard for a rover, so we’re a little ways off,” said John Grunsfeld, NASA’s associate administrator for science.

“I think (the discovery) will really drive the ingenuity of our scientists and engineers to come up with a viable experiment – and hopefully we can do it in the 2020s -- that would go and investigate these areas and perhaps even return samples from these areas some day,” he added.

The existence of regions associated with present day water also means that visiting rovers must be properly sterilized to assure that hitchhiking Earth microbes don’t contaminate potential native populations.

“We’re being very careful that we don’t send a spacecraft to Mars with the intention of detecting Martian life and find out that we’ve detected the Earth life that we took with us,” Grunsfeld said.

Curiosity, which has provided evidence that ancient Mars had the necessary ingredients and suitable environments for microbial life, could end up playing a role in the search for present-day water as well.

Scientists have noticed RSL-like streaks in the walls of Mount Sharp, the three-mile high mound rising from the floor of Gale Crater, which Curiosity has been exploring since August 2012.

“We don’t really know if Curiosity will have an opportunity to go to one of these areas and make measurements,” said NASA’s planetary science chief Jim Green. “They may or may not be RSLs. We've got a lot of work to do on that.”

After three years of intense radiation exposure on Mars, Curiosity could be sterile enough to venture near a potential RSL, but its suite of instruments might not be suited for the job, Green added.

“It has a limited set of capabilities to be able to make any sort of detection in this area,” he said.

Read more at Discovery News

Sep 28, 2015

Tasmanian Devils Set Free in Test of New Vaccine

Twenty Tasmanian devils were released into Narawntapu National Park in northern Tasmania on September 26, each inoculated with a new vaccine against a deadly disease that has decimated the endangered species.

The animals (11 males and 9 females) received a vaccine against devil facial tumor disease, a condition that causes cancers to form around and inside the devil's mouth, making eating difficult and ultimately causing death by starvation.

The disease is rare in that it's a contagious cancer -- spread by bites among the devils or through sharing food or eating an infected carcass.

Thanks to the disease, Tasmanian devil populations have declined by more than 60 percent in the last 10 years, according to the International Union for Conservation of Nature's "red list" of endangered species.

The release was carried out under the aegis of an initiative called the Wild Devil Recovery Project, a Tasmanian government-funded joint effort between the Menzies Institute for Medical Research and the Save the Tasmanian Devil Program (STDP).

The newly wild devils, formerly kept at a free-range enclosure site for "insurance" populations, will join existing devils already living in the park, and they will be monitored over time to gauge the vaccine's effectiveness.

The hope is that the re-wilding program will not only boost the devil populations but also increase their genetic diversity.

"The next milestone will be to see them start breeding in the wild and thus further ensuring their chances of survival into the future," said Bob Wiese, director of living collections for San Diego Zoo Global, an STDP partner in Tasmania, in a press release.

From Discovery News

Sea Otter with Asthma Learns to Use an Inhaler

The air was hazy from forest fires, and Mishka, a 1-year-old sea otter at the Seattle Aquarium, could barely breathe.

Aquarium staff jumped into action, putting an oxygen mask on the 45-lb. (20 kilograms) sea otter and administering anti-inflammatory medication to help her breathe. After several medical tests, Mishka became the first-known sea otter (Enhydra lutris) to be diagnosed with asthma.

Now, trainers are teaching Mishka how to use an inhaler — one that's not designed for sea otters (after all, Mishka is the first one) but for cats, said Seattle Aquarium staff veterinarian Dr. Lesanna Lahner.

"She's very smart, and she's picking it up quite quickly," Lahner told Live Science. "But being an otter, she's also extremely playful. So we have to work with her and with her playfulness to make it fun."

Mishka is relatively new to the Seattle Aquarium. The Alaska native was rescued after people found her tangled in a fishing net in July 2014, according to the aquarium. She spent the next several months in rehabilitation at the Alaska SeaLife Center. However, the U.S. Fish and Wildlife Service deemed her nonreleasable because she never learned critical survival skills, such as how to forage for food, and thus would be unable to survive in the wild, Lahner said.

Zookeepers named her Mishka, Russian for "little bear," when she arrived in Seattle in January. They didn't realize she had asthma until months later, when smoke from the forest fires in eastern Washington floated over the Cascade Range mountains into western Washington.

On Aug. 22, zookeepers noted that Mishka was acting lethargic and not eating much.

"It's abnormal for a sea otter not to eat pretty voraciously," Lahner said.

The next day, Mishka had a full-blown asthma attack, prompting immediate treatment.

Afterward, Lahner took a blood sample to make sure Mishka didn't have pneumonia or another respiratory pathogen (she didn't). Then, Lahner listened to Mishka's lungs with a stethoscope and took a radiograph of the animal's chest. The results pointed toward asthma, she said.

The radiograph showed that Mishka had abnormal thickening on her bronchial walls. This can make it difficult for enough oxygen to enter the lungs — a pattern that "is typical of what is seen in cats presenting with acute asthma," Lahner said.

Trainers are giving Mishka food rewards to use a device called the AeroKat, which has a chamber filled with aerosolized medicine. Mishka is learning to put her nose against a rubber face piece that's connected to the medicine-filled chamber, and take a couple of breaths.

Read more at Discovery News

Meet 'Microsnail,' Now the World's Smallest Snail

The world’s smallest known terrestrial snail has just been discovered in China.

The snail, Angustopila dominikae, measures just .03 inches tall — nearly 10 of them could fit into the eye of a sewing needle.

Named after the wife of lead author Barna Páll-Gergely from Shinshu University, the snail is described in the journal ZooKeys.

“Extremes in body size of organisms not only attract attention from the public, but also incite interest regarding their adaptation to their environment,” Páll-Gergely and his team wrote.

“Investigating tiny-shelled land snails is important for assessing biodiversity and natural history as well as for establishing the foundation for studying the evolution of dwarfism in invertebrate (lacking a backbone) animals.”

The scientists found the snail while examining soil samples collected from the base of limestone rocks in Guangxi Province, Southern China. Seven snails were found, represented just by their now-empty light grey shells.

The researchers also found six other new small species of terrestrial snails. Yet another of the new species, Angustopila subelevata, was a tiny fraction larger than A. dominikae. Both are considered “microsnails.” They are also sometimes called “micromolluscs.”

It can be challenging to discover such animals. The molluscs are delicate, often overlooked, and are rarely found alive. The bodies degrade long before the shells do. Not much is known about how many different microsnails might exist in this particular ecosystem, not to mention, elsewhere in the world.

The researchers also do not know yet what the snail might eat, or what the evolutionary relationship is between the different species.

From Discovery News

Mystery Solved: Water DOES Flow on Mars

Scientists have their first evidence that trickles of liquid water play a role in sculpting mysterious dark streaks that appear during summertime months on Mars, a finding that has implications for potential life on Mars, as well as planning for future human expeditions.

The discovery, reported Monday in the journal Nature Geoscience, follows years of speculation and studies to learn why the faces of some cliff walls on Mars are streaked with narrow dark slopes, some more than 300 feet long, that appear when temperatures are warm and then vanish during the winter chill.

The streaks, known as recurring slope lineae, or RSL, were first reported in 2011 in the Martian southern highlands, but have since been found throughout the planet’s equatorial region, particularly within deep canyons.

Using data collected by NASA’s Mars Reconnaissance Orbiter and a new analysis technique, scientists were for the first time able to detect the telltale chemical fingerprints of hydrated salts in dozens of RSL sites.

“That implies that there was liquid water there very recently to leave this residue of hydrated salts. It confirms that water is playing a role in these features,” University of Arizona planetary geologist Alfred McEwen told Discovery News.

In a press conference advisory, NASA said that the research “solves” a Mars mystery, but it actually opens the door to another, potentially more challenging puzzle: Where is the water coming from?

“We haven’t been able to pinpoint the source,” lead researcher Lujendra Ojha, a graduate student at Georgia Institute of Technology, told Discovery News.

“Water could form by the surface/subsurface melting of ice, but the presence of near-surface ice at equatorial latitudes is highly unlikely,” Ojha and colleagues write in Nature Geoscience.

Another option is that salts absorb water vapor directly from the Martian air, though scientists are at a loss to explain how they could trap enough water from the tiny amount available in the atmosphere to seep down hill slopes and form the streaks.

“It’s just not clear that the atmosphere can supply enough water to do that,” McEwen said.

Whatever the source of the water, its seasonal appearance on the surface of Mars raises the prospect that life might be present on the planet today.

Read more at Discovery News

Rosetta's Comet is Actually 2 Comets Glued Together

Scientists have solved the mystery of why the comet being studied by Europe’s Rosetta spacecraft is shaped like a rubber duck -- it started off as two separate comets, a new study shows.

Ever since Rosetta sent back pictures of its twin-lobed target more than a year ago, scientists have debated whether the comet, known as 67P/Churyumov-Garasimenko, could be the result of two comets that merged together during the solar system’s early years.

The other option is that the so-called “neck region” between 67P’s two lobes experienced some particularly active and still unexplained outgassing over the eons, eroding its more spherical shape into a body that resembles a rubber duck.

“Our study rules out the possibility that the comet shape is the outcome of erosion,” planetary scientist Matteo Massironi, with the University of Padova in Italy, wrote in an email to Discovery News.

Rather, the neck region is where two independent bodies collided, analysis of high-resolution images taken by the orbiting Rosetta spacecraft shows.

“The heating and partial melting at the impact location and the subsequent cooling and gluing of the two bodies explain the shape of the neck region,” Massironi wrote.

In a paper published in this week’s Nature Geoscience, scientists say that 67P’s lobes are made up of similar, but independent stratified, “onion-like” layers.

“Geological sections through the comet show that the larger lobe is made up of strata up to 650 meters (2,133 feet) thick, which are independent of analogous stratified layers on the smaller lobe,” the scientists wrote.

“Our analysis ... clearly shows that the layers of the body and the head of the comet are not related,” Massironi said.

Combining the geological data with measurements of the comet’s gravity, and Rosetta scientists conclude that 67P is the result of two independent bodies that gently and repeatedly impacted before merging together soon after the formation of the solar system some 4.6 billion years ago.

Read more at Discovery News

Sep 27, 2015

Green storage for green energy

A team of Harvard scientists and engineers has demonstrated a rechargeable battery that could make storage of electricity from intermittent energy sources like solar and wind safe and cost-effective for both residential and commercial use. The new research builds on earlier work by members of the same team that could enable cheaper and more reliable electricity storage at the grid level.

The mismatch between the availability of intermittent wind or sunshine and the variability of demand is a great obstacle to getting a large fraction of our electricity from renewable sources. This problem could be solved by a cost-effective means of storing large amounts of electrical energy for delivery over the long periods when the wind isn't blowing and the sun isn't shining.

In the operation of the battery, electrons are picked up and released by compounds composed of inexpensive, earth-abundant elements (carbon, oxygen, nitrogen, hydrogen, iron and potassium) dissolved in water. The compounds are non-toxic, non-flammable, and widely available, making them safer and cheaper than other battery systems.

"This is chemistry I'd be happy to put in my basement," says Michael J. Aziz, Gene and Tracy Sykes Professor of Materials and Energy Technologies at Harvard Paulson School of Engineering and Applied Sciences (SEAS), and project Principal Investigator. "The non-toxicity and cheap, abundant materials placed in water solution mean that it's safe -- it can't catch on fire -- and that's huge when you're storing large amounts of electrical energy anywhere near people."

The research appears in a paper published in the journal Science.

This new battery chemistry was discovered by post-doctoral fellow Michael Marshak and graduate student Kaixiang Lin working together with co-lead author Roy Gordon, Thomas Dudley Cabot Professor of Chemistry and Professor of Materials Science at Harvard.

"We combined a common organic dye with an inexpensive food additive to increase our battery voltage by about 50 percent over our previous materials," says Gordon. The findings "deliver the first high-performance, non-flammable, non-toxic, non-corrosive, and low-cost chemicals for flow batteries."

Unlike solid-electrode batteries, flow batteries store energy in liquids contained in external tanks, similar to fuel cells. The tanks (which set the energy capacity), as well as the electrochemical conversion hardware through which the fluids are pumped (which sets peak power capacity), can be sized independently. Since the amount of energy that can be stored can be arbitrarily increased by scaling up only the size of the tanks, larger amounts of energy can be stored at lower cost than traditional battery systems.

The active components of electrolytes in most flow battery designs have been metal ions such as vanadium dissolved in acid. The metals can be expensive, corrosive, tricky to handle, and kinetically sluggish, leading to inefficiencies. Last year, Aziz and his Harvard colleagues demonstrated a flow battery that replaced metals with organic (carbon-based) molecules called quinones, which are abundant, naturally occurring chemicals that are integral to biological processes like photosynthesis and cellular respiration. While quinones in aqueous solution formed the negative electrolyte side of the battery, the positive side relied on a conventional bromine-bearing electrolyte that is used in several other batteries. The high performance and low cost of the technology, which Harvard has licensed to a company in Europe, hold the potential to provide scalable grid-level storage solutions to utilities.

But bromine's toxicity and volatility make it most suitable for settings where trained professionals can deal with it safely behind secure fences.

So the team began searching for a new recipe that would provide comparable storage advantages -- inexpensive, long lasting, efficient -- using chemicals that could be safely deployed in homes and businesses. Their new battery, described in a paper published today in the journal Science, replaces bromine with a non-toxic and non-corrosive ion called ferrocyanide.

"It sounds bad because it has the word 'cyanide' in it," explains co-lead author Marshak, who is now assistant professor of chemistry at the University of Colorado Boulder. "Cyanide kills you because it binds very tightly to iron in your body. In ferrocyanide, it's already bound to iron, so it's safe. In fact, ferrocyanide is commonly used as a food additive, and also as a fertilizer."

Because ferrocyanide is highly soluble and stable in alkaline rather than acidic solutions, the Harvard team paired it with a quinone compound that is soluble and stable under alkaline conditions, in contrast to the acidic environment of their original battery developed last year.

Marshak compares exposure to the concentrated alkaline solution to coming into contact with a damaged disposable AA battery. "It's not something you want to eat or splash around in, but outside of that it's really not a problem."

There are other advantages to using alkaline solution. Because it is non-corrosive, the flow battery system components can be constructed of simpler and much less expensive materials such as plastics.

"First generation flow batteries were single-element couples -- transition metals like vanadium or iron or chrome," says Michael Perry, Project Leader for Electrochemical Systems at United Technologies Research Center, who was not involved in the work. "Now we're seeing the possibility of engineered molecules giving us the properties and attributes that we want in one complete system. More work is required and justified but the Harvard team is really demonstrating the promise of next-generation chemistries."

Robert F. Savinell, Distinguished University Professor and George S. Dively Professor of Engineering at Case Western Reserve University, another battery expert who was not part of the Harvard research, agrees that the new technology offers significant advantages over other flow batteries concepts, including "potential very low costs with sustainable materials, high efficiencies at practical power densities, and safe and simple operation." He adds: "It should be expected that this flow battery approach will have a short development and scale-up path for fast commercial introduction."

Harvard's Office of Technology Development has been working closely with the research team to navigate the shifting complexities of the energy storage market and build relationships with companies well positioned to commercialize the new chemistries.

The demand for battery storage is driven by regulatory factors as much as economic ones. In some states, as well as many parts of the world, if it can't be instantaneously used by meeting electricity demand, solar energy incident on solar panels goes to waste unless the electricity is stored. However, in many states, customers have the right to sell electricity produced by rooftop solar panels at high consumer rates under a regulatory scheme called net metering. Under those circumstances, consumers have little incentive to install batteries. But market experts like William W. Hogan, Raymond Plank Professor of Global Energy Policy at Harvard Kennedy School, believe that such policies are ultimately "uneconomic and unsustainable." And as more and more homeowners install solar panels, utilities are opposing requirements to buy electricity from their customers.

Hogan says net metering is one of a series of "regulatory gimmicks designed to make solar more attractive" and predicts that eventually consumers with rooftop photovoltaic panels will lose the option of exchanging electricity for discounts on their utility bills. When that happens, these homeowners have an incentive to invest in battery storage.

Read more at Science Daily

'Fossils' of galaxies reveal the formation and evolution of massive galaxies

An international team led by researchers at Swiss Federal Institute of Technology in Zürich observed massive dead galaxies in the universe 4 billion years after the Big Bang with the Subaru Telescope's Multi-Object InfraRed Camera and Spectrograph (MOIRCS). They discovered that the stellar content of these galaxies is strikingly similar to that of massive elliptical galaxies seen locally. Furthermore, they identified progenitors of these dead galaxies when they were forming stars at an earlier cosmic epoch, unveiling the formation and evolution of massive galaxies across 11 billion years of cosmic time.

In the local universe, massive galaxies hosting more than about 100 billion stars are predominantly dead elliptical galaxies, that is, without any signs of star-formation activity. Many questions remain on when, how and for how long star formation occurred in such galaxies before the cessation of star formation, as well as what happened since to form the dead elliptical galaxies seen today.

In order to address these issues, the research team made use of fossil records imprinted by stars in the spectra of distant dead galaxies which give important clues to their age, metal content, and element abundances. Local massive dead galaxies are about 10 billion years old and rich in heavy elements. Also, α-elements, which measure the duration of star formation, are more abundant than iron, indicating that these galaxies formed a large amount of stars in a very short period. The team investigated the stellar content of galaxies in the distant universe 4 billion years after the Big Bang, in order to study galaxy evolution much closer to their formation epoch.

The team took the advantage of the MOIRCS's capability to observe multiple objects simultaneously, efficiently observing a sample of 24 faint galaxies. They created a composite spectrum that would have taken 200 hours of Subaru Telescope's time for a single spectrum of comparable quality.

Analysis of the composite spectrum shows that the age of the galaxies is already 1 billion years old when observed 4 billion years after the Big Bang. They host 1.7 times more heavy elements relative to the amount of hydrogen and their α-elements are twice enhanced relative to iron than the solar values. It is the first time that the α-element abundance in stars is measured in such distant dead galaxies, and it tells us that the duration of star formation in these galaxies was shorter than 1 billion years. These results reveal that these massive dead galaxies have evolved to today without further star formation.

What do massive dead galaxies look like when they are forming stars? To answer this, the team investigated the progenitors of their sample based on their spectral analysis. The progenitors must be star-forming galaxies in the universe 1 billion years before the observed epoch for the dead galaxies. Indeed, they do find similarly massive star-forming galaxies at the right epoch and with the right star formation rate expected from the spectra. If these active galaxies continue to create stars at the same rate, they will immediately become more massive than seen in the present universe. Therefore, these galaxies will cease star formation soon and simply age.

Read more at Science Daily