Dec 13, 2014
New sonar maps show for the first time the mud-covered grave of the SS City of Rio de Janeiro, nearly 300 feet (91 meters) below the surface. The steamer sank on Feb. 22, 1901, just before reaching its destination, with 210 people on board, most of them Chinese and Japanese immigrants.
"The overwhelming response looking at the imagery of the Rio is one of sadness," said James Delgado, director of maritime heritage for National Ocean and Atmospheric Administration's (NOAA) Office of National Marine Sanctuaries. When the ship sank, "it was front-page news all over the world. It was a terrible tragedy," he said.
The City of Rio spent two months at sea, making stops in Hong Kong; Yokohama, Japan; and Honolulu before returning to San Francisco. On the morning of the accident, pilot Frederick Jordan had been steering the 345-foot (105 m) steamer through the Golden Gate strait (three decades before construction on the bridge started). But under heavy fog, the City of Rio struck jagged rocks near Fort Point, at the southern end of the strait. The ship was badly damaged and sank within just 10 minutes, trapping many passengers riding in the cabin and in steerage. In total, 128 people were killed.
In the 1980s, a salvage team claimed to have found the shipwreck. However, the team lost its equipment trying to reach the underwater site, and later, it turned out that the coordinates the team recorded didn't match up with those of the wreck site, Delgado said.
Last month, the companies Hibbard Inshore and Bay Marine Services donated a research vessel and crew to NOAA for a day. The agency used the opportunity to look for the City of Rio using a 3D sonar device known as Echoscope developed by the company Coda Octopus. NOAA was able to find and map the City of Rio, and the crew even had time to map the nearby SS City of Chester, a wreck that was recently rediscovered.
The City of Chester, destined for Eureka, California, went down on Aug. 22, 1888, after colliding with the RMS Oceanic, a ship that was arriving from Asia. Of the 90 people on board, 16 were killed. Delgado and his team thought the City of Chester would be buried in mud, but instead, it's quite exposed, with its boilers and engines still mounted in place.
"You see the bones of the ship laid out," Delgado said. "You see the machinery in place in an environment that would otherwise be completely unknown and inaccessible."
In contrast, the City of Rio is in bad shape. The vessel is collapsing under a thick layer of mud. At some point since it sank, the ship's front half broke off and slid down a 65-foot (20 m) slope. Even without its mud coating, the ship would be nearly impossible to salvage with current technology because of its depth and the strong currents surrounding the wreck, Delgado said. In his view, the City of Rio is in a "sealed grave."
Read more at Discovery News
This newest photo release from the European Space Agency’s Rosetta spacecraft has got to be the biggest anticlimax from an otherwise thrilling mission so far. However, the science behind the photo completely eclipses Comet 67P/Churyumov-Gerasimenko’s monochrome surface.
“As it turns out, 67P/C-G looks dark grey, in reality almost as black as coal,” said Holger Sierks, from the Max Planck Institute for Solar System Research (MPS) and principal investigator for Rosetta’s OSIRIS instrument, in a Rosetta blog update today (Dec. 12).
Taken through OSIRIS’s three color filters of red, green and blue, this photographic version of the familiar comet is our first ‘true color’ view of the dusty surface since Rosetta arrived in orbit in August. Although there are some very slight color variations, the comet would look just like this to the human eye — predominantly dark grey.
OSIRIS stands for Optical, Spectroscopic, and Infrared Remote Imaging System, and the instrument has been painstakingly capturing every small detail on the comet’s surface.
When observed from afar, long before Rosetta arrived at 67P, astronomers had an idea that the cometary surface would have, on average, a greyish color. But on closer inspection, Rosetta mission scientists are surprised by how grey the body is, even on the finest of scales. This signifies that the comet’s nucleus has very little compositional variations on its surface.
One would normally expect to see a slightly blue hue over regions dominated with ice, for example. Although other instruments on Rosetta suggest there is an abundance of ice throughout the comet, its presence certainly isn’t seen by OSIRIS. Instead, 67P is homogeneously covered in a fine dust that gives it a very uniform appearance.
Read more at Discovery News
Dec 12, 2014
The finding is reported in one of eight studies published today in Science by the Avian Phylogenomics Consortium, an international collaboration examining the evolution of living birds.
In total 23 papers are being simultaneously published this morning, revealing new insights into questions such as what makes a bird a bird; how colourful feathers and vocal learning developed; and the evolutionary tree of all avians.
The tooth study answers a question that has long baffled evolutionary biologists: did tooth loss in birds happen convergently across a number of bird lineages or through a common ancestor?
It uses data from whole-genome sequencing of 48 bird species that represent nearly all living bird orders, as well as the American alligator, a representative of Crocodylia (the closest living relatives of birds).
Co-author Professor Mark Springer, of the University of California Riverside, says it has been known that modern birds descended from a toothed ancestor since the discovery of Archaeopteryx in 1861.
Archaeopteryx lived around 150 million years ago and is considered a transitional species between dinosaurs and birds. Although it had wings, it also had jaws with sharp teeth and stood on two legs.
Later fossil finds also revealed animals with partial beaks, but in the back of the jaw they still had teeth.
Springer says this makes evolutionary sense.
"You can't expect that an ancestor would have gone through a stage when all of the teeth would have been lost, but there was no beak," Springer, of the Department of Biology, says.
"That would have made it too hard to do all the things they needed to do like feeding themselves or their young.
"Once you get that partial beak, then you can continue to lose the teeth more posterially until they become completely replaced by the beak."
However, he says the history of final tooth loss in the ancestry of modern birds has remained elusive for more than 150 years.
Mutant tooth genes the key
For the study the team looked for shared mutations in the six genes that are essential for the formation of dentin and enamel, the building blocks of teeth.
"Tooth formation is very complex in terms of the hundreds of genes involved … most of these genes are not only involved in tooth formation they are involved in other developmental processes as well."
The six genes they isolated were the "best candidates for being specific to teeth".
"If teeth are gone then natural selection should not maintain these genes," says Springer.
If the genes were found to be non-functioning due to mutations in all 48 bird species they studied, this would indicate loss through a common ancestor.
"We can then use this record of mutations to estimate when the teeth were in fact lost," he says.
The team, which also includes Professor Thomas Gilbert, a visiting academic at Curtin University in Western Australia, found enamel-related genes were disabled in the common ancestor of modern birds about 116 million years ago.
The researchers also examined the genomes of a number of toothless vertebrates including three turtles and four mammals (pangolin, aardvark, sloth, and armadillo) for these same mutations.
They found these vertebrates also had mutations in the dentin and enamel genes, making them non-functional.
By comparison all six genes were functional in the American alligator.
"Dead genes" are an important tool, says Springer. They are "chock full of information, it's like finding a fossil in the rocks".
"They are still in our genome, but full of these inactivating mutations so they don't function anymore.
"This DNA from the crypt is a powerful tool for unlocking secrets of evolutionary history."
Read more at Discovery News
In 525 B.C., Persian King Cambyses marched into Memphis, the Egyptian capital, inaugurating a period of Persian rule that would last for more than a century. The Persian Empire was a vast entity that stretched from modern-day Afghanistan to the west coast of Turkey. Ancient texts say that the Persian kings deported Egyptian artists and used them for building projects in Persia.
The coffin bears a series of unusual features that are likely related to the Persian Empire's deportation of artists.
"Many of the best artists in Egypt were taken by the Persians back to Persepolis and Susa as POWs and war booty -- you can see their work in those places. There seems to have been a dearth of masters for some time, so that fewer and fewer artists got proper training," Gayle Gibson, an Egyptologist and educator at Toronto's Royal Ontario Museum, told Live Science in an email.
Gibson presented the coffin at the Society for the Study of Egyptian Antiquities Scholars' Colloquium, which was held Nov. 13 to 16 in Toronto.
There are several odd features on the coffin that reflect the lack of knowledge the ancient artist had, Gibson said.
For instance, the deceased is depicted lying on a funerary bed, and the bed has a human-headed bird called a Ba. Flying over the deceased is a winged snake wearing a crown associated with the goddess Hathor. Below them are four jars bearing the heads of the four Sons of Horus, but the jars have a "goofy" appearance, Gibson said.
To an Egyptologist, this is a bizarre scene, Gibson said. "This is the only funerary bed I know of with a Ba's head," she told the Toronto audience, also noting that "we have a winged snake with Hathor's crown -- very odd."
There are other oddities. The collar wrapped around the top of the coffin contains two creatures that look almost fishlike. The artist was likely trying to draw falcons, a symbol of the god Horus, but drew them very poorly, Gibson said.
A Mehen snake, a protective deity in Egypt, is also poorly drawn and actually stops at one point and starts in another, something strange for a protective deity. "The artist doesn't really understand the purpose of the Mehen snake," Gibson said.
Mike Sigler, a collector and Egyptian antiquities enthusiast who lives in Kentucky and now owns the coffin, sent a picture to Live Science showing that the ancient artist clumsily attempted to correct an error in an alternating pattern by scratching out an image of a scepter.
Ancient brain drain
Although there is no longer a mummy in the coffin, its inscriptions say that it belonged to someone named Denit-ast, or Dent-ast, likely a woman. Radiocarbon dating of her coffin indicates that she lived at a time when her country was under Persian control.
Ancient texts tell tales of the deportation of Egyptian artists to Persia during this time. Diodorus Siculus, who died around 30 B.C., said that Cambyses, the conqueror of Egypt, transferred both precious metals and artists from Egypt to Persia.
Additionally, Persian King Darius I bragged about the Egyptian artists he acquired in a text describing the construction of his palace at Susa. "The goldsmiths who wrought the gold, those were Mede and Egyptians. The men who wrought the wood, those were Sardians and Egyptians … the men who adorned the wall, those were Medes and Egyptians" Darius said (translation by Roland Kent).
Gibson told the Toronto audience that when she first showed the coffin to other Egyptologists, some expressed skepticism and wondered if it was a fake created before Sigler owned it.
However, radiocarbon dating places the coffin in the Persian period and analysis of its wood indicates that it's sycamore, a wood that was commonly used in ancient Egypt. Additionally, an analysis of the coffin's blue pigments found that the pigment was Egyptian blue, which indicates that the coffin is authentic, Gibson said.
Sigler purchased the coffin in August 2013 from the Edgar L. Owen gallery, which sold it on behalf of a private collector. Paperwork that Sigler received indicates that the collector acquired it from the European art market in 1980. Its history before that is unknown.
Gibson is well known for her Egyptological work. In the 1990s she helped identify a mummy in Niagara Falls, Canada, as likely being that of pharaoh Ramesses I. The mummy was later returned to Egypt with full military honors.
Given Gibson's reputation, Sigler sought her out and asked her for help in understanding the coffin's strange features.
Despite its odd features, Gibson believes the coffin is not a fake. "I think there is really no doubt that this one is genuine," she said.
Read more at Discovery News
While poring over data collected by the European Space Agency's XMM-Newton spacecraft, a team of researchers spotted an odd spike in X-ray emissions coming from two different celestial objects — the Andromeda galaxy and the Perseus galaxy cluster.
The signal corresponds to no known particle or atom and thus may have been produced by dark matter, researchers said.
"The signal's distribution within the galaxy corresponds exactly to what we were expecting with dark matter — that is, concentrated and intense in the center of objects and weaker and diffuse on the edges," study co-author Oleg Ruchayskiy, of the École Polytechnique Fédérale de Lausanne (EPFL) in Switzerland, said in a statement.
"With the goal of verifying our findings, we then looked at data from our own galaxy, the Milky Way, and made the same observations," added lead author Alexey Boyarsky, of EPFL and Leiden University in the Netherlands.
Dark matter is so named because it neither absorbs nor emits light and therefore cannot be directly observed. But astronomers know dark matter exists because it interacts gravitationally with the "normal" matter we can see and touch.
And there is apparently a lot of dark matter out there: Observations of star motion and galaxy dynamics suggest that about 80 percent of all matter in the universe is "dark," exerting a gravitational force but not interacting with light.
Researchers have proposed a number of different exotic particles as the constituents of dark matter, including weakly interacting massive particles (WIMPs), axions and sterile neutrinos, hypothetical cousins of "ordinary" neutrinos (confirmed particles that resemble electrons but lack an electrical charge).
The decay of sterile neutrinos is thought to produce X-rays, so the research team suspects these may be the dark matter particles responsible for the mysterious signal coming from Andromeda and the Perseus cluster.
If the results — which will be published next week in the journal Physical Review Letters — hold up, they could usher in a new era in astronomy, study team members said.
Read more at Discovery News
|Don’t you be coy with me, you little pervert.|
Should you be foolish enough to drop trou and answer the call of nature in the wilderness, you’ll find the beast will “enter your body by the most unspeakable means,” said Carl Franklin, a herpetologist at the University of Texas at Arlington. “And it’ll rip your guts, shred them to pieces.” The death is slow, not to mention embarrassing.
OK, it’s not true—the creature, a reptile called the Mexican mole lizard, is in fact totally adorable and completely harmless—but it sure is a powerful myth. A few years ago Franklin was driving through Baja with his wife searching for the critters, and pulled up to two cowboys. He handed them a picture of the mole lizard and asked if they’d seen any lately, and “they just twisted up their faces in disgust, and they went over and saw my license plate is from Texas.” They then proceeded to admonish him for coming to their country for such things.
“I get to the next town, 10 miles away,” Franklin recalls, “and I see a young guy walking on the side of the road and I stop and I ask him and he just starts backing up, and he says, ‘Hey mister we’re all really good people here. My uncle just called me and told me you were coming.’”
|The Mexican mole lizard eats just about anything small enough and soft enough. Except ice cream. It never really comes across ice cream.|
Part of the problem with finding these things is that they’re subterranean, burrowing through sandy soil with their reinforced heads while scooping back debris with those well-developed claws. It’s no wonder, then, that they’ve lost their back legs. Often in evolution it makes sense for a structure to evolve away if it’s no longer useful, or indeed a detriment, sparing you the energy and resources and time needed to build it. As a bonus, what you don’t have can’t get injured—or in the case of the Mexican mole lizard’s hind limbs, perhaps losing lose legs means you can move better through the soil.
The creature’s eyes are quite beady and underdeveloped. “If you’re basically a mute inhabitant in a dark underworld, you gotta figure that touch and taste and smell are going to be the three keen senses,” said Franklin. “So anything like vibrations, they certainly can feel, but finding mates and even locating prey, it’s going to be chemosensory” cues, which they pick up with their tongue.
Mexican mole lizards spend so much time underground in search of food that they lack the melanin that gives organisms their color. “These guys, man they would need lots of SPF, because they’re really fair skinned,” and accordingly emerge only at dusk, Franklin said. You can even shine a flashlight right through them (which is technically known as “candling,” by the way).
And these things are about as comfortable above ground as we are below it. It’s hard to classify their method of locomotion. The critter isn’t using its limbs much, and it isn’t quite slithering. It’s actually anchoring itself at points along its body, then pushing forward. This makes sense underground: By contracting itself against the walls of its burrow, the Mexican mole lizard can slowly inch forward, leaving its limbs free to shove loose soil back.
|Those powerful claws help the creature shovel dirt out of the way.|
The Mexican mole lizard isn’t blessed with such a shell, so how does it regulate its body temperature? For the moment, Franklin isn’t sure, though he notes that he’ll find them in the roots of vegetation, perhaps taking advantage of the cooler soil under the plant’s shade. “So they would just move from one site to the next for thermoregulatory needs, is my educated guess.”
Read more at Wired Science
Dec 11, 2014
The elusive creatures, which have adapted to their lightless environment by losing their eyes, were discovered in Grand Canyon-Parashant National Monument, which abuts the better-known Grand Canyon National Park.
Unlike true scorpions, these scorpion imposters lack a tail with a venomous stinger. Instead, the arachnids use venom-packed stingers in their pincers to immobilize their prey, study author J. Judson Wynne, an assistant research professor in the Department of Biological Sciences at Northern Arizona University, in Flagstaff, wrote in an email.
The tiny cave where the team discovered the new species — just 250 feet (76 meters) in length — nevertheless supports the highest diversity of cave-adapted arthropods of any known cave in the Grand Canyon-Parashant National Monument, Wynne said.
The researchers first discovered the two false scorpions during expeditions in a cave along the north rim of the Grand Canyon, between 2005 and 2007. But it took years before the team identified the species as unique.
"Contrary to popular belief, rarely are we in the field, collect an animal and then brandish our grubby field flasks of whiskey to toast a new species discovery," Wynne told Live Science in an email.
To confirm the scorpion lookalikes were a new species, the team had to take them back to a taxonomic specialist, who analyzed all the details of the species and pored over all the existing data on similar species. In this case, the team found that one of the species had a thickened pair of legs and a mound on the pincer, while another had a much deeper pincer than other pseudoscorpions — qualifying each as a distinct species, study co-author Mark Harvey, senior curator at the Western Australian Museum in Perth, said in an email.
The creatures, dubbed Hesperochernes bradybaughii and Tuberochernes cohni, respectively, are about 0.12 inches (3 millimeters) long and feed on tiny invertebrates, including springtails, book lice, mites and possibly cricket nymphs. Many of their prey are just one-fourth the length of a grain of rice.
The two species are named after Jeff Bradybaugh, an advocate for cave research and the former superintendent of Grand Canyon-Parashant National Monument, and Theodore Cohn, an entomologist who identified a new genus of cave cricket and passed away in 2013.
The fact that two separate species of pseudoscorpion can live in the cave while competing for the same food source suggests the cave supports a robust food web. The cave is one of the largest roosts of crickets in northern Arizona, and the pseudoscorpion prey feed on the cricket "frass," or poop, as well as the fungus that grows on the poop. The cave is also home to a bizarre, eyeless fungus beetle that feeds on the poop fungus.
At one time, the pseudoscorpions' ancestors lived in the desert environment outside the cave, but they have since adapted to hunting in an environment devoid of light, losing their eyes and gaining an elongated bodies in the process.
In general, pseudoscorpions are odd creatures. Not only are their pincers good for immobilizing prey, they also help the insects hitchhike to new locales.
"They will grasp onto another animal such as birds, mammals and even other insects. They hold on and can be transported long distances," Wynne said.
Read more at Discovery News
The newly discovered species hails from 520 million years ago, during the Cambrian Period, when life on Earth exploded in diversity. Dubbed Nidelric pugio, this creature had a balloonlike body covered in an exoskeleton of spines. Nothing precisely like it exists today, researchers reported in a new study published today (Dec. 9) in the journal Scientific Reports.
"We usually only get the broken-up remains of ancient animal skeletons," study researcher Tom Hearing, a doctoral student in geology at the University of Leicester, said in a statement. "With this specimen we can see how all the different parts of the skeleton stuck together."
The Cambrian was a bizarre time for life on Earth. During this period, animals evolved that would later give rise to modern-day creatures. Other lineages died out, leaving behind strange fossils that hardly fit modern conceptions of life. A bristly, shield-headed giant measuring 2.7 feet long (70 centimeters) trolled the ocean, filter-feeding for small shrimplike organisms. Eyeless, figure-8 shaped animals, called vetulicolians, roamed the sea. A spiny worm was so weird and confusing that the researchers who first discovered it thought its legs were its spine and its head was its backside.
N. pugio was probably a chancelloriid, a group that does not seem to be the ancestor of anything living today. These animals get squashed during fossilization, so their fossils look like bird's nests.
The name of the new species comes from the Latin word Nidus, which means "bird's nest," and the old English name Aedelic, which honors the late paleontologist Richard Aldridge, whose name derives from the same root. Aldridge was an expert in Cambrian fossils from Chengjiang, a formation in southwestern China where the new species was found. Paleobiologist Xianguang Hou of Yunnan University led the research team.
Read more at Discovery News
The new figure estimates that the oceans hold more than 250,000 tons of trash, a number vastly different from a past estimate, which suggested the oceans' plastic is mysteriously disappearing.
Scientists arrived at the new number by combining visual estimates of trash volume with data collected from trawling the oceans with nets, said study co-author Markus Eriksen, director of research for the 5 Gyres Institute, an organization aiming to understand the plastic pollution in the ocean.
World of plastic
The detritus of everyday life has been pouring into the oceans for decades. Everything from plastic bags to water bottles have migrated from the coastlines, harbors and river mouths into the oceans, where gyres, or the ocean's giant conveyor belts, carry them to the most remote stretches of the seas.
About 15 years ago, scientists discovered the Great Pacific Garbage Patch, a trash-filled region of the Pacific Ocean the size of Texas. A recent excursion even found that islands of trash were forming in the garbage patch.
In the 1970s, studies suggested that about 45,000 tons of plastic littered the ocean, and the world's production of plastic has increased fivefold since then. But scientists don't agree on just how much of the world's plastic makes its way into the ocean, or how long it lasts before fish, sunlight and currents break it down and carry it into the deep ocean. In dozens of expeditions, scientists have tried to estimate this number by visual counts or by trawling the seas with nets.
But the first method is better at picking up large objects, such as buoys and fishing nets, whereas the second method may be more reliable for tiny, broken down pieces of plastic that are floating in the water column.
In the new study, Eriksen said he and his colleagues looked at ocean plastic estimates from 24 expeditions to all of the world's five gyres, from Iceland to the Bay of Bengal.
The team combined both visual plastic surveys and net hauls with mathematical models for how ocean circulation would transport plastic, and compared these results based on the size categories of the plastic garbage. The new estimates suggest that about 5.25 trillion plastic particles, weighing about 269,000 tons, litter the oceans. Nearly 75 percent of that weight came from large plastic objects such as buoys, buckets and other fishing gear.
The model also suggests that ocean circulation acts like "giant shredders," breaking down large plastics that predominate at the coastlines into smaller bits, with the tiniest pieces overrepresented in the subpolar regions, Eriksen told Live Science.
Given that much of the ocean detritus is heavy gear such as buoys or fishing nets, it's not feasible to use robots to trawl the seas and collect trash, Erikson said. Instead, an incentive program -- for instance, offering a dollar per pound for fishermen to bring in plastic trash -- could help people clean up the oceans on their own, he added.
Read more at Discovery News
If the earthquake severely damaged cellphone towers and severed fiber-optic cables and power lines that supply the electricity needed to run Internet servers, millions of residents suddenly might be unable to communicate via text messages or connect to online to navigate, and getting crucial information from authorities about the emergency would become difficult.
With supermarkets increasingly reliant upon the Internet to do just-in-time stocking of their shelves, local communities quickly might also run out of food.
For these reasons, a just-issued report by the office of Los Angeles mayor Eric Garcetti advocates creating a backup: a citywide, solar-powered WiFi network that would keep residents online despite the catastrophe.
“This low-powered system could serve as a way to maintain communication through email and texting, should electrical system failures cause other communications systems to fail,” the report explains.
Other parts of the country are developing such systems as well. In Hoboken, N.J., where communications were disrupted by Hurricane Sandy in 2012, volunteers are crowd-sourcing a backup called MileMesh. The latter utilizes a technology called wireless mesh networking, in which network access is provided by scores of small, inexpensive radio transmitters that act both as wireless routers and relays that connect to one another. MileMesh’s organizers are aiming to get at least some of the volunteers to invest in $500 solar panels to power their routers.
Building a solar-powered backup system is critical, because keeping commercial cell towers online could prove difficult if a quake knocks out power lines that cross the San Andreas Fault. The towers are too energy-hungry to make it practical to supply them with solar panels or backup generators for very long, the report said.
Read more at Discovery News
Dec 10, 2014
The dinosaur, described in the latest issue of PLOS ONE, has been named Aquilops americanus, meaning “American eagle face.” It lived around 108 million years ago.
That date is significant for the record books.
“Aquilops lived nearly 20 million years before the next oldest horned dinosaur named from North America,” paleontologist Andrew Farke from the Raymond M. Alf Museum of Paleontology explained in a press release. “Even so, we were surprised that it was more closely related to Asian animals than those from North America.”
This dinosaur wasn’t exactly kissable. Its cheekbones were like spikes, with a pointy edge protruding at the tip. Its sharp beak could also do some serious damage, as could the spikes on the top of its nose area, the back of its head and those down its neck.
Farke, who led the research on the dinosaur, considers these features to be a “ceratopsian membership card.”
The term “ceratopsian” refers to four-legged, plant-eating dinosaurs, including famous triceratops. They lived during the Cretaceous period. Like this new dino, they were known for their beaks, horned heads and the bony frills that protected their necks.
This latest discovery, when combined with other fossil finds, suggests that the ancestors of these dinosaurs underwent a great intercontinental migratory event between Asia and North America around 113 million years ago. The migration could have continued for the next few million years, but the scientists are continuing to investigate why and exactly when this all happened.
Adding to the evidence for such a migration is the fact that, as Farke indicated, Aquilops shares many features with horned dinosaurs known from Asia.
Read more at Discovery News
Coming from the Akhmim cemetery, on the east side of the Nile in Upper Egypt, the gold-painted, lavishly decorated sarcophagus was acquired by Chicago’s Field Museum in 1925.
“From the CT scans we took in 2011, we can see that the mummy is a boy, about 14 years old, apparently in good physical condition,” Field Museum curator J.P. Brown told Discovery News.
According to the inscription on the coffin, the boy was named Minirdis. He was the son of Inaros, the hereditary stolist priest of Min, the Egyptian fertility god.
As a stolist priest, Minirdis’s father was a powerful individual who was responsible for ritually washing and clothing the statue of the god.
“Minirdis would likely have inherited the office had he lived,” Brown said.
Using specially created clamps as a cradle to lift the coffin lid, Brown and colleagues opened the sarcophagus. The aim was to restore and stabilize the mummy before it tours the country in the upcoming exhibit “Mummies: Images of the Afterlife.”
The burial mask and the blackened toes are the only visible part of the mummy. The rest of the teenage body remained wrapped in a yellowing embalming cloth.
“The linen of the shroud and wrappings was quite brittle and this further complicated the operation,” he added.
As they removed the mummy, Brown and colleagues also found a previously unknown drawing of the Goddess Nut on the bottom of the coffin.
Read more at Discovery News
To recreate the conditions thought to exist on Earth when life began, scientists used a giant laser to ignite chemical reactions that converted a substance found on the early Earth into the molecular building blocks of DNA, the blueprint for life.
The findings not only offer support for theories of how life first formed, but could also aid in the search for signs of life elsewhere in the universe, the researchers said.
The beginning of life coincides with a hypothetical event that occurred 4 billion to 3.85 billion years ago, known as the Late Heavy Bombardment, in which asteroids pummeled Earth and the solar system's other inner planets. These impacts may have provided the energy to jumpstart the chemistry of life, scientists say.
In 1952, the chemists Stanley Miller and Harold Urey conducted a famous experiment at the University of Chicago in which they simulated the conditions thought to be present on early Earth. This experiment was intended to show how the basic materials for life could be produced from nonliving matter.
Recent studies suggest that asteroid impacts may break down formamide — a molecule thought to be present in early Earth's atmosphere — into genetic building blocks of DNA and its cousin RNA, called nucleobases.
In their new study, chemist Svatopluk Civiš, of the Academy of Sciences of the Czech Republic, and his colleagues used a high-powered laser to break down ionized formamide gas, or plasma, to mimic an asteroid strike on early Earth.
"We want to simulate the impact of some extraterrestrial body an early stage of the atmosphere of Earth," Civiš told Live Science.
They used the Asterix iodine laser, a 490-feet-long (150 meters) machine that packs about 1,000 Joules of power at its peak, which is equivalent to the amount produced by an atomic power station, Civiš said. The laser was only switched on for half a nanosecond, however, because that is comparable to the time frame for an asteroid impact, he said.
The reaction produced scalding temperatures of up to 7,640 degrees Fahrenheit (4,230 degrees Celsius), sending out a shock wave and spewing intense ultraviolet and X-ray radiation. The chemical fireworks produced four of the nucleobases that collectively make up DNA and RNA: adenine, guanine, cytosine and uracil.
Using sensitive spectroscopic instruments, the researchers observed the intermediate products of the chemical reactions. These instruments measure the chemical fingerprint of the molecules formed during the course of a reaction. Afterward, the team used a mass spectrometer, a device that measures the masses of chemicals, to detect the final products of the reactions.
The breakdown of formamide produced two highly reactive chemicals or "free radicals" of Carbon and Nitrogen (CN) and Nitrogen and Hydrogen (NH), which could have reacted with formamide itself to produce the genetic nucleobases, the researchers said.
The findings, detailed today (Dec. 8) in the journal Proceedings of the National Academy of Sciences, provide a more detailed mechanism for how the basic chemistry of life got started.
Read more at Discovery News
Scientists have long wondered how Earth got its water. Any indigenous water molecules likely were lost to space during the planet’s hot and violent formation.
The leading theory is that the water came later, during a period roughly 800 million years after the solar system’s formation when the inner planets were being blitzed by asteroids, comets and other small bodies. It was during this time, known as the “late heavy bombardment” that a Mars-sized object is believed to have crashed into Earth, sending clouds of debris into space that later consolidated into the moon.
With their icy bodies, comets were an early first choice to be Earth’s water-bearers, an idea buttressed by studies three years ago when Europe’s Herschel spacecraft made chemical measurements of water in another Kuiper Belt transplant, Comet Hartley 2. Its water matched Earth’s perfectly.
Comet 67P/Churyumov-Gerasimenko, the subject of the ongoing Rosetta studies, tells a different story. Its water has three times more of the hydrogen isotope deuterium than Earth’s water, one of the highest concentrations ever measured in a solar system body, said University of Bern’s Kathrin Altwegg, lead researcher for one of Rosetta’s science instruments.
“That now probably rules out Kuiper Belt comets as bringing the water on the Earth,” Altwegg said.
Even a mixture of water from Hartley 2-type comets and those chemically similar to 67P would have too much deuterium to match what exists on Earth today.
The ratio of deuterium to regular hydrogen in 67P is so high “you need only a small fraction of these comets to (spoil) the Hartley 2 results if you mix them up to make terrestrial water,” Altwegg told Discovery News.
Additional measurements from other comets may shed more light on the mystery. The new findings, the first reported since Rosetta arrived at Comet 67P in August, increase the odds that asteroids were the source of Earth’s water.
“Today asteroids have very limited water, that’s clear. But that was probably not always the case. The late heavy bombardment was 3.8 billion years ago and at that time asteroids could well have had much more water than they have today. They have just lived in the vicinity of the sun for 4.6 billion years” and lost water due to heating, Altwegg said.
“Comets also are amazingly asteroid-like … in their non-ice components,” added astronomer Donald Brownlee, with the University of Washington and lead researcher for NASA’s Stardust mission, which in 2006 returned samples from a comet.
The Rosetta results also show that comets hailing from the Kuiper Belt, a region of icy bodies beyond Neptune’s orbit, formed at different distances from the sun and under different conditions.
That idea is consistent with results from the Stardust mission, which found large-scale mixing of materials formed in the inner and outer solar system.
Rosetta scientists and engineers meanwhile continue the hunt for the Philae lander, which last month touched down on the comet’s surface, bounced twice and finally came to rest at a still-to-be-determined location, most likely in a crater.
“One side of the lander appears to be in a hole. We see the legs sticking up in the air. We can see a bit of the sky. We also see an overhanging cliff-like structure, so it gives us an idea of what the local terrain is like,” said Rosetta project scientist Matt Taylor with the European Space Agency.
Read more at Discovery News
|Does Saturn have life on it? If you count gas as life, then yeah, sure.|
Here’s what Dick figured. At the time, there were an average of 280 people per square mile in England. And because he thought every surface of our universe bears life, it would naturally occur at roughly the same population density. So from comets and asteroids to the rings of Saturn, if you knew how big something was, you could guess how many beings live there. Thus, Jupiter would be the most populated object in the solar system, with 7 trillion beings. The least populated would be Vesta, the second largest asteroid in the asteroid belt, tallying just 64 million.
Dick, you see, was a very religious man, but also a voracious scientist, one of the last of the so-called natural theologists, who looked for signs of God’s influence in nature. For Dick, it simply did not make sense for God to have created the cosmos just to have it sit around unoccupied. There must be creatures out there capable of enjoying its beauty, because God wants all his work appreciated.
|Well thanks very much, Thomas. Nice of you to say.|
If you think waterfalls and sunsets here on Earth are neato, Dick promises you’ll be floored by what you’d see on other planets. “What should we think of a globe appearing in our nocturnal sky 1,300 times larger than the apparent size of the moon, and every hour assuming a different aspect?” he asked. “What should we think of a globe filling the twentieth part of the sky, and surrounded with immense rings, in rapid motion, diffusing a radiance over the whole heavens?” It’s a lovely image, isn’t it? These are also scenes we see realized in modern sci-fi—from a brain that was ticking fully two centuries ago.
You might think that living on other worlds might be difficult, but Dick assures us they’re arranged much like Earth, with mountains and valleys and such. The moon in particular has “an immense variety of elevations and depressions,” and while we can’t directly observe such features on Jupiter, Saturn, or Uranus, given their distance, when light hits them it reveals “the spots and differences of shade and color which are sometimes distinguishable on their disks,” thus betraying the uneven surfaces underneath. (We know today, of course, that these are all in fact gas giants.)
|The gas giants aren’t really this close to each other. They have pretty big personal space bubbles.|
There is, though, the rather glaring problem of the crushing gravity of a planet the size of Saturn. But Dick posits that “the density of Jupiter is little more than that of water, and that of Saturn about the density of cork.” Jupiter, therefore, would have a gravity only twice as great as Earth’s—not so terrible in the grand scheme of things.
For as bizarre as all this may seem, notice how scientific Dick was about his theory. This was not mere daydreaming. He had numbers, and he had principles, and with them he formulated a wildly wrong idea, but nevertheless pieced it together fairly logically. And he wasn’t even the first scientist to argue that life existed elsewhere in our solar system. Far from it: It was none other than the famed astronomer William Herschel who argued that not only was there life on every planet, but on the sun as well. That blinding glow we see is simply a luminous atmosphere hiding a rocky surface that teemed with life.
And oddly enough, it was Herschel’s son John who indirectly eclipsed Dick in an epic way.
The Great American Tradition of Newspapers That You Can’t Even Remotely Trust
According to Paul Collins in his book Banvard’s Folly: Thirteen Tales of People Who Didn’t Change the World, on August 21, 1835, the New York Sun dropped a bombshell of a story: Astronomer Sir John Herschel had erected an enormous telescope in South Africa that could magnify celestial bodies an astounding 42,000 times. And when he pointed it at the moon he saw a field of poppies.
It was all just a hoax, but the issue sold like mad. And so, four days later, the paper dropped another bombshell: Herschel next saw bison on the moon. And not just bison, but monsters of “bluish lead color, about the size of a goat, with a head and beard like him, and a single horn, slightly inclined forward from the perpendicular.” Not only that, but bipedal beavers as tall as humans. Based on the Sun’s account, Collins describes them “skating gracefully among their villages of tall huts, which all had chimneys, showing them to be acquainted with the use of fire.”
Then on August 28th came the kicker. Herschel had spotted humans up there on the moon—4-foot-tall humans “with short and glossy copper-colored hair, and had wings composed of a thin membrane,” the Sun reported. They had built giant sapphire pyramids, and apparently had a fondness for cucumbers. Perhaps more importantly for the hoaxster journalists—Richard Adams Locke (a descendent of philosopher John Locke) and Sun publisher Moses Beach—The New York Times and New York Evening Post endorsed the claims as entirely plausible. So it seemed a good a time as any for the men to compile their stories into a book: Great Astronomical Discoveries Lately Made by Sir John Herschel at the Cape of Good Hope, 60,000 copies of which sold out in a flash.
|Notice the whatcha thinkin bout bat person at lower left.|
|John Herschel, supposed discoverer of life on the moon and a 24/7 party animal.|
And just two years after Dick’s death, Charles Darwin published On the Origin of Species. Dick’s brand of natural theology, long on the wane, would not survive it. Darwin had put forth a shocking theory (for Victorian minds, at least) that explained life as we know it without a creator. Even true scientists with strong allegiances to God, like Richard Owen, who famously battled Darwin’s blasphemous idea to his death, were snuffed by the intellectual tsunami that was evolution by natural selection.
Read more at Wired Science
Dec 9, 2014
The ancient tracks, made by the chicken-size dinosaur Corvipes lacertoideus, contain strange features that are likely the marks made when the dino withdrew its foot from the sediment — a process that is impossible to document without X-rays that reveal what's below the sediments.
The new video "is the first time anyone has been able to see a footprint being formed," said study author Peter Falkingham, a research fellow at the University of London's Royal Veterinary College.
Falkingham and his colleagues used X-rays to videotape a bird called a guineafowl (a relative of chickens and pheasants) as it walked through a soft bed of poppy seeds. The researchers could see the foot plunging into the seeds, just as a dinosaur foot might have sunk into soft sand or dirt.
Dinosaur prints are the only direct record of dinosaur movement, Falkingham told Live Science. But they are very tricky to interpret. A fossil print might come from the original land surface where the dinosaur stepped, or it might be an impression left over from several rock layers down, after the surface layer eroded away.
Prints are static impressions, Falkingham said, but a moving dinosaur foot is dynamic. Unlike celebrities carefully pressing their handprints into the cement on the Hollywood Walk of Fame, a walking dino didn't create an anatomically correct impression in the ancient soil. The dinos sank down, swept their toes through the dirt and flexed their foot muscles as they moved. Without an understanding of this process, scientists can only glean so much from dinosaur tracks.
Falkingham and his colleagues wanted to peer below the surface, second by second, as a track was being made. They chose guineafowl as their subjects because the birds are close in size to the dinosaur print fossils that the researchers wanted to use as comparisons. And, as birds, guineafowl are descendents of the avian dinosaurs.
"They are small dinosaurs without a tail, and that makes them a fantastic correlate for looking at the footprints produced by dinosaurs and produced by birds," Falkingham said.
In an X-ray machine, the birds trotted over solid surfaces and through dry poppy seeds, an analogue for sand or other soft sediment. Next, the researchers used computer simulations to model the movement of every single little poppy seed as the bird strode through.
The video provides a real-time look at how a footprint is formed — the first time anyone has been able to see what a bird's foot does in soft sediment, Falkingham added. The researchers found that the guineafowl's feet sank about 1.9 inches (5 centimeters) down into the poppy seeds, a depth that is almost equal to the length of the bird's feet. On the dry, granular surface, only an indistinct impression remained, more of a trench than a track.
But about 0.4 inches (1 cm) below the surface, the impression of the bird's foot was preserved in startling detail.
That preservation occurs because the poppy seeds balance against one another below the surface, rather than collapsing as they do up top, the researchers report today (Dec. 8) in the journal Proceedings of the National Academy of Sciences.
But this subterranean print was not a faithful reproduction of the bird's foot anatomy. The shape of the animal's claw changed as it moved through the seeds, first plunging low, then sweeping back. The toes entered the seeds spread wide, then clenched together as they retracted, like the clasper in a claw arcade game.
This movement left distinct impressions, mimicked in the Corvipes tracks from the Jurassic period in what is now the northeastern United States. By comparing the modern bird foot simulations with the real Jurassic tracks, Falkingham and his colleagues were able to see how mysterious ridges in the track formed.
"The simulation shows us that as the foot comes out, it comes out in the middle of the track and it pulls sediment upwards while it does so," Falkingham said. "So these are actually exit traces from the foot."
Read more at Discovery News
The group was caught red-handed looting historical artifacts, and the robbers were apprehended in what Israeli officials called a "dramatic capture" that played out along the high cliffs of a region of the Judean Desert known as the Leopard's Ascent.
"For many years now, gangs of antiquities robbers have been operating along the Judean Desert cliffs," Amir Ganor, director of the Israel Antiquities Authority's unit for the prevention of antiquities robbery, said in a statement.
"The robbers attempt to locate and find the Dead Sea Scrolls, pieces of ancient texts and unique artifacts that were left in the caves." The artifacts are then sold for large sums of money in Israel and around the world, he added.
Members of the Israeli police force's search-and-rescue team were recently undergoing routine training on the cliffs when they noticed movement in a nearby cave. The team reported the incident to the Israel Antiquities Authority, which placed the cave under surveillance.
Not long after, the suspected robbers were observed again, equipped with metal detectors and other excavation equipment. Upon leaving the cave, the looters were immediately apprehended by Israeli officials, who confiscated several ancient artifacts, including a 2,000-year-old lice comb from the Roman period.
The gang of looters indicted yesterday is one of the main criminal groups operating out of the Judean Desert, according to Israeli officials. In addition to the rock-climbing gear used to reach the looted cave, the alleged criminals were found in possession of excavation tools — so-called break-in equipment, metal detectors, lighting equipment and enough food and water to last several days.
"What makes the Judean Desert so unique is its dry climate that enable the preservation of rare leather, bone and wooden objects, including the Judean Desert Scrolls, pieces of parchment and papyruson which various texts were written, among them the Holy Scriptures, books of the Bible, legal contracts and historical stories," Ganor said.
The Judean Desert Scrolls, more commonly known as the Dead Sea scrolls, is a collection of texts discovered in the 1940s in a series of caves located in the northwest of the Judean Desert. Included in the texts were copies of the books of Genesis, Exodus, Isaiah, Kings and Deuteronomy. Archaeologists have also found other ancient scrolls in the region, some of which date back 2,000 years.
Read more at Discovery News
The extreme California drought? Maybe not so much.
A new National Oceanic and Atmospheric Administration study released Monday shows that the three-year California drought may have been caused by natural variability and not necessarily human-caused climate change.
The study follows a series of studies released in September that were inconclusive about the role of climate change in the California drought, and another published last week showing that the drought is the worst the state has seen in 1,200 years.
The devastating 3-year drought, which began in 2011 and is ongoing despite recent rains, was caused by a high pressure system that was sitting over the West Coast and part of the North Pacific Ocean, driving moisture away from California, report co-author Richard Seager, a professor of oceanography at the Columbia University Lamont-Doherty Earth Observatory in Palisades, N.Y., said.
The persistence of the high pressure ridge was also present in previous long-term droughts in California, some of which were longer than the current drought. The ridge was initially caused by cool sea surface temperatures in the Pacific brought about by a La Niña in 2011, but it persisted even after cool ocean surface temperatures began to warm, the study says.
“Two-thirds of the precipitation deficit in California were due to factors we wouldn’t judge to have long predictability at all,” report co-author Martin Hoerling, a NOAA research meteorologist in Boulder, Colo., said. “They resulted from the randomness of the atmosphere.”
Despite the extreme drought, winter precipitation in California has followed no particular trend since 1895 and is expected to increase because a low pressure system is expected to park itself over the North Pacific each winter, driving moisture into the state, Hoerling said.
Even though the drought may not have been caused by climate change, the drought’s effects may be worse because of hotter temperatures on land that may be caused by global warming, the study says.
Kevin Trenberth, senior scientist at the National Center for Atmospheric Research in Boulder, called the study useful, but said it comes up short in many ways.
“I would contend that all droughts are largely natural in the sense that they arise from internal variability in the atmosphere-ocean system,” he said. “But this study completely fails to consider what climate change is doing to water in California. It completely misses any discussion of evapotranspiration and the increased drying associated with global warming.”
The extra heat in the atmosphere from global warming enhances drying on the surface and increases the risk of heat waves, worsening the effects of a drought, Trenberth said.
But the study is useful because it shows that most of what caused the drought and allowed it to persist was predictable, he said.
Trenberth said it’s puzzling that the study ignores that 2013 was California’s driest year on record, and the study is contradicted by the research published last weekconcluding that the drought isunprecedented in 1,200 years.
The lead author of that study, Woods Hole Oceanographic Institution researcher Kevin Anchukaitis, said that he believes the conclusions of his study and the NOAA study are actually complementary because both studies use different techniques and different information sources.
Read more at Discovery News
To account for a lake that lasted for millions or even tens of millions of years means the Martian atmosphere would have had to be not only far thicker than the puny envelope of gases that surrounds it today, but also loaded with water, said Ashwin Vasavada, deputy project scientist for NASA's Curiosity Mars rover.
The Curiosity science team announced Monday that the 96-mile-wide crater where the rover landed in August 2012 was once a lake.
"The landscapes of Mount Sharp indicate that rivers, lakes and groundwater were present over millions of years, something that would be impossible on Mars today," Vasavada said.
Today, water on Mars is frozen around the planet's poles. Even if the atmosphere were thicker (generating pressure that would permit water to exist as a liquid, rather than just as solid or gas) water would still preferentially gather in the polar regions, leaving the atmosphere dry. Gale Lake would have evaporated quickly.
"To get a long-lived lake in Gale Crater there must have been so much water in the climate system that the frozen latitudes were essentially filled up, that water was forced to warmer latitudes where it would exist as liquid," Vasavada said.
To humidify the atmosphere, Mars would need a vigorous hydrological cycle fed by either warmer ice at lower latitudes or a large expanse of liquid water, like an ocean.
"A humid atmosphere would slow the evaporation of Gale Lake and also resupply water to precipitation," Vasavada said.
Since the 19070s-era Viking days, scientists have been looking for remnants of a Martian ocean. They've found tantalizing hints, such as a network of valleys and channels cut into the highlands that lead downward toward a large basin. However, concrete evidence, like a shoreline, may have been obliterated by erosion.
"There is no smoking gun for an ocean in the northern hemisphere," Vasavada said.
Even accounting for greenhouse gases, computer models currently fall short in explaining how Mars could have stayed warm enough to sustain a lake like Gale for millions of years.
"Constructing a model of Mars ancient climate that was thick, warm and humid for millions of years has proven pretty challenging," Vasavada said.
Read more at Discovery News
Dec 8, 2014
Maternal DNA from ancient Norsemen closely matches that of modern-day people in the North Atlantic isles, particularly from the Orkney and Shetland Islands.
The findings suggest that both Viking men and women sailed on the ships to colonize new lands. The new study also challenges the popular conception of Vikings as glorified hoodlums with impressive seafaring skills.
"It overthrows this 19th century idea that the Vikings were just raiders and pillagers," said study co-author Erika Hagelberg, an evolutionary biologist at the University of Oslo in Norway. "They established settlements and grew crops, and trade was very, very important."
Vikings hold a special place in folklore as manly warriors who terrorized the coasts of France, England and Germany for three centuries. But the Vikings were much more than pirates and pillagers. They established far-flung trade routes, reached the shores of present-day America, settled in new lands and even founded the modern city of Dublin, which was called Dyfflin by the Vikings.
Some earlier genetic studies have suggested that Viking males traveled alone and then brought local women along when they settled in a new location. For instance, a 2001 study published in the American Journal of Human Genetics suggested that Norse men brought Gaelic women over when they colonized Iceland.
To learn more about Norse colonization patterns, Hagelberg and her colleagues extracted teeth and shaved off small wedges of long bones from 45 Norse skeletons that were dated to between A.D. 796 and A.D. 1066. The skeletons were first unearthed in various locations around Norway and are now housed in the Schreiner Collection at the University of Oslo.
The team looked at DNA carried in the mitochondria, the energy powerhouses of the cell. Because mitochondria are housed in the cytoplasm of a woman's egg, they are passed on from a woman to her children and can therefore reveal maternal lineage. The team compared that material with mitochondrial DNA from 5,191 people from across Europe, as well as with previously analyzed samples from 68 ancient Icelanders.
The ancient Norse and Icelandic genetic material closely matched the maternal DNA in modern North Atlantic people, such as Swedes, Scots and the English. But the ancient Norse seemed most closely related to people from Orkney and Shetland Islands, Scottish isles that are quite close to Scandinavia.
"It looks like women were a more significant part of the colonization process compared to what was believed earlier," said Jan Bill, an archaeologist and the curator of the Viking burial ship collection at the Museum of Cultural History, a part of the University of Oslo.
That lines up with historical documents, which suggest that Norse men, women and children — but also Scottish, British and Irish families — colonized far-flung islands such as Iceland, Bill told Live Science. Bill was not involved with the new study.
"This picture that we have of Viking raiding — a band of long ships plundering — there obviously would not be families on that kind of ship," Bill said. "But when these raiding activities started to become a more permanent thing, then at some point you may actually see families are traveling along and staying in the camps."
Read more at Discovery News
The impressive view comes from an ambitious experiment called EarthScope, which has scanned the country from California to Maine using hundreds of portable seismometers. (The next stop is Alaska.) Launched in 2004, the massive effort has already revealed new details about the geology of the western and central United States, such as the shape of Yellowstone's magma plume. Now, the first clear images of the entire continent are beginning to emerge, according to a study published Oct. 15 in the journal Geophysical Research Letters.
"This was the dream to start with," said Brandon Schmandt, lead study author and a seismologist at the University of New Mexico in Albuquerque.
The EarthScope process resembles snapping a CT scan of the Earth, with a field crew moving sensitive earthquake detectors across the surface and researchers constructing an image of the rocks below.
In the new study, Schmandt and his co-author, Fan-Chi Lin of the University of Utah, built a detailed, 3-D map of the Earth's upper mantle, which is the rocky layer between the crust and core. The results could help researchers solve some long-standing geologic puzzles. The mantle is not only a time capsule, preserving the history of crashing tectonic plates, but also a force that influences what happens at the surface.
Clues to geologic mysteries may lie hidden in the mantle, the study reports. One mystery is why there are a handful of 48-million-year-old volcanoes in Virginia, when no other volcanic features have formed on the East Coast since about 200 million years ago.
The East Coast has been a passive margin, with no colliding tectonic plates, for 200 million years, so the Virginia volcanoes are unusual features, Schmandt said. But it turns out that the mantle beneath the East Coast isn't as cold and dense as one might expect after so many millennia free from jostling.
The researchers found alternating zones within the mantle where earthquake waves shift gears, from fast-moving and slow-moving speeds and back. This differs from the more uniform mantle under the old and tectonically stable central United States. (Earthquake waves speed up and slow down when they hit rocks with different temperature, density or composition.)
The new model revealed that two of sites where seismic waves suddenly slow down match up with geological features on the Earth's surface. One is in the central Appalachians, centered directly below the Virginia volcanoes. The second, located in the northern Appalachians, lines up with a feature called the Great Meteor hotspot track in Canada, Schmandt said. The track is a chain of progressively younger volcanoes that starts in Canada and stretches out into the Atlantic Ocean.
Further work on the anomalies could help explain why Virginia's rare volcanoes appeared. For instance, Schmandt said he was impressed that 50 million years later, the mantle beneath the volcanoes is still altered by whatever process triggered the eruptions. "It's a little bit surprising to see these strong changes in a place that's been a passive margin for such a long time," Schmandt told Live Science.
To the south, a puzzling bite in the Appalachian Mountains called the Mississippi Embayment stands out sharply in the new model. The corner-shaped region of the embayment pokes northwest from the Mississippi River delta. Geologists have long argued over what created the embayment, which is concealed under miles of Mississippi River mud.
The new data suggests a piece of North America was ripped out long ago, then later replaced by another drifting chunk, perhaps a piece of an island chain similar to Japan. "It really looks like a different type of lithosphere in there," Schmandt said. Fragments of islands and other continents that smashed onto North America can appear as hotter mantle regions beyond the outline of the original continent.
Some of the clearest shapes in the new mantle map are ancient relics. Earlier studies have shown North America sits above a graveyard for discarded pieces of old ocean floor. The pieces of oceanic crust (or slabs) were consumed at a subduction zone offshore the West Coast. A subduction zone is where one plate sinks underneath another. "It's fascinating to see slabs that subducted 10 to 100 million years ago," Schmandt said. "It tells us what the driving forces were like in the past."
But beneath North America, the slabs of crust aren't sinking in the way scientists thought they would. Schmandt and Lin discovered fragments of old oceanic crust at about 310 miles (500 kilometers) depth under the central and eastern United States, whereas younger pieces of oceanic crust have dropped nearly twice that depth beneath the western United States. The researchers suggest a large piece of oceanic crust that subducted more than 40 million years ago broke into several large fragments, at least two of which foundered.
Read more at Discovery News
When the runners found out that they'd been given nothing more powerful than an injection of salt water, many were red-faced and a little embarrassed, lead author Ramzy Ross said. While the subjects may have felt duped, however, it's actually another testament to the power of expectation on our health, placebo experts said. Other work has shown that placebos can soothe a baby's cough, relieve migraine pain, and even mend torn knee cartilage as well as surgery.
One of the key issues in placebo research is parsing out what makes them work, said John Kelley, deputy director of the Program in Placebo Studies at Harvard Medical School and an associate professor of psychology at Endicott College.
The two most common components, he said, are conscious expectations and classical conditioning. Think of the first as what you could verbalize: In the case of the runners, for example, most would say that taking erythropoietin (EPO) would improve their aerobic capacity and delay fatigue. As for classical conditioning, just as Pavlov's dogs started salivating when the physiologist entered the room in anticipation of being fed, people experience physical responses to certain associations.
In fact, even when researchers tell subjects they're taking a placebo, so-called open label studies still show a positive placebo effect.
Researchers attribute it to the conditioning response, Kelley said. It works best in people who have been treated previously for a condition. People with migraine headaches who experienced pain relief by taking a certain drug in the past also felt better when taking a pill that looked similar -- even when they knew it was not the actual drug.
By that rationale, athletes who have previously blood doped for real might fare even better on sham EPO, Kelley said. Previous research on cyclists showed that the benefits of taking morphine during workouts were maximized when the cyclists were preconditioned to using it first. Ramzy's team also delivered the placebo to the runners via injections instead of pills, knowing that most people have a stronger reaction to more invasive procedures.
Read more at Discovery News
Take this latest example, as imaged by the High-Resolution Imaging Science Experiment (HiRISE) camera on board NASA’s Mars Reconnaissance Orbiter (MRO), which looks like a freshly baked cookie.
This strange circular landform was spotted in the Athabasca region of the Red Planet, where some of the youngest lava flows are known to reside. The feature is around 2 kilometers (1.2 miles) wide and appears to contain some rather lumpy landscaping, whereas the region surrounding it is almost perfectly smooth.
Planetary scientists aren’t sure what caused the ‘cookie,’ but suspect it was ‘baked’ out of the surface material when Mars was volcanically active millions of years ago.
According to a NASA Jet Propulsion Laboratory (JPL) news release, the ancient lava flow may have seeped underground, pushing this mound up from below. The lumpiness of the mound may be due to ice being melted out of the surface layers, causing some collapse of material.
There are many strange features like these in Athabasca and, like this peculiar circle, an explanation isn’t easy to come by.
From Discovery News
The discovery is based on data collected by Curiosity over the past 2.5 years, including findings of sediment beds of sandstones that are inclined toward Mount Sharp, a three-mile high mound rising from the center of a 96-mile wide impact crater.
“We can see a whole series of beds, of sandstones, with some pebble beds in there, that are actually inclined at a large scale toward the south,” Curiosity scientist Sanjeev Gupta, with Imperial College in London, told reporters on a conference call.
Scientists believe that means that not only did Mount Sharp not exist at the time, but that Curiosity’s Gale Crater landing site was once -- and possibly many times over -- a shallow lake.
Similar inclined beds are found on Earth at the mouths of river channels where they feed into lakes, Gupta said.
The research indicates that Mount Sharp formed from sediments deposited in the center of the lakebed over millions of years. The sediments would have been carried in rivers originating from the crater rim highlands -- which may have been capped in snow or ice -- and ending in the waters that filled the crater basin. Scientists suspect that winds later eroded the deposits, eventually creating the mountain.
"We are beginning to think that maybe Mount Sharp formed in a series of episodes involving sedimentation and erosion, stacked by different processes," said lead Curiosity scientist John Grotzinger, with the California Institute of Technology in Pasadena.
Scientists suspect there were many cycles of wet and dry times at Gale Crater and that the cycle continued for millions or tens of millions of years, boosting chances that conditions were suitable for microbial life.
Read more at Discovery News
Dec 7, 2014
The record efficiency was achieved in outdoor tests in Sydney, before being independently confirmed by the National Renewable Energy Laboratory (NREL) at their outdoor test facility in the United States.
The work was funded by the Australian Renewable Energy Agency (ARENA) and supported by the Australia-US Institute for Advanced Photovoltaics (AUSIAPV).
"This is the highest efficiency ever reported for sunlight conversion into electricity," UNSW Scientia Professor and Director of the Advanced Centre for Advanced Photovoltaics (ACAP) Professor Martin Green said.
"We used commercial solar cells, but in a new way, so these efficiency improvements are readily accessible to the solar industry," added Dr Mark Keevers, the UNSW solar scientist who managed the project.
The 40% efficiency milestone is the latest in a long line of achievements by UNSW solar researchers spanning four decades. These include the first photovoltaic system to convert sunlight to electricity with over 20% efficiency in 1989, with the new result doubling this performance.
"The new results are based on the use of focused sunlight, and are particularly relevant to photovoltaic power towers being developed in Australia," Professor Green said.
Power towers are being developed by Australian company, RayGen Resources, which provided design and technical support for the high efficiency prototype. Another partner in the research was Spectrolab, a US-based company that provided some of the cells used in the project.
A key part of the prototype's design is the use of a custom optical bandpass filter to capture sunlight that is normally wasted by commercial solar cells on towers and convert it to electricity at a higher efficiency than the solar cells themselves ever could.
Such filters reflect particular wavelengths of light while transmitting others.
ARENA CEO Ivor Frischknecht said the achievement is another world first for Australian research and development and further demonstrates the value of investing in Australia's renewable energy ingenuity.
Read more at Science Daily