Jan 30, 2015
The plant-eating dinosaur, Qijianglong guokr, had an unusual body that was half neck. It lived about 160 million years ago and is described in the latest issue of the Journal of Vertebrate Paleontology.
The construction crew that happened upon the dinosaur remarkably managed to unearth the dinosaur with its head still attached to its long, narrow neck.
"It is rare to find a head and neck of a long-necked dinosaur together because the head is so small and easily detached after the animal dies," co-author Tetsuto Miyashita said in a press release.
"Qijianglong is a cool animal," added Miyashita, who is a University of Alberta paleontologist. "If you imagine a big animal that is half neck, you can see that evolution can do quite extraordinary things."
Most sauropods (i.e. long-necked, plant-eating dinosaurs) have necks that are about one-third the length of their bodies, so "Dragon of Qijiang" sported quite a neck. The researchers determined that its vertebrae were filled with air, making it lighter in weight than the neck bones of other animals.
Interlocking joints between the vertebrae, however, meant that the neck was surprisingly stiff. The researchers suspect that the neck was more mobile going up and down, like a construction crane, than it was moving from side to side.
"Dragon of Qijiang" is classified as a mamenchisaurid, a group of dinosaurs known for their long necks. This type of dinosaur has thus far only been found in Asia.
"Qijianglong shows that long-necked dinosaurs diversified in unique ways in Asia during Jurassic times–something very special was going on in that continent," said Miyashita. "Nowhere else we can find dinosaurs with longer necks than those in China. The new dinosaur tells us that these extreme species thrived in isolation from the rest of the world."
The paleontologists speculate that a sea, or other natural barrier, could have caused the isolation.
The "Dragon" and its kind were survivors, though. As other long-necked dinosaurs bit the dust in Asia, mamenchisaurids thrived, evolving into different types, including this half-neck form.
Read more at Discovery News
Preempting the official research paper that is planned to be published next week, the ESA, who manages the Planck space telescope data, has gone on the record to say that the BICEP2 measurements of B-mode polarization in the cosmic microwave background (CMB) was caused not by the presence of primordial gravitational waves, but by obscuring dust inside our own galaxy. The CMB is the left-over ancient radiation from the Big Bang that occurred nearly 14 billion years ago.
“Despite earlier reports of a possible detection, a joint analysis of data from ESA’s Planck satellite and the ground-based BICEP2 and Keck Array experiments has found no conclusive evidence of primordial gravitational waves,” writes an ESA statement.
This null result doesn’t come as a surprise to many scientists in the field, however.
Since the media storm that surrounded one of the would-be biggest cosmological discoveries in modern history in March 2014, the BICEP2 data has been heavily scrutinized. Although the BICEP2 telescope, a US-led project based near the South Pole, is designed to detect the tell-tail ‘wiggle’ in the polarization of CMB radiation caused by the presence of gravitational waves, great care needs to be taken when interpreting the results.
Should gravitational waves be detected, not only would their discovery be monumental, it would also confirm some key models of the universe’s origin, thereby revealing the mechanisms behind inflation — the split-second expansion of the universe immediately after the Big Bang.
However, between us and the outermost reaches of our observable universe there is magnetized material within our own galaxy. Any radiation detected beyond our galaxy has to travel through the interstellar dust and the signal needs to be corrected for. But to correct for our galaxy’s dust, you need to precisely map it first — this is where the European Planck space telescope comes in.
Before it went silent in 2013, Planck was surveying the sky, mapping the CMB. But it was also mapping the intervening magnetic field and dust content of our galaxy. These data are critical to subtract from CMB measurements if B-mode polarization is to be detected. But in March 2014, when the BICEP2 researchers announced their results to the world, the precision Planck dust map was not available.
Now that the Planck survey data has been processed, it seems that the BICEP2 ‘signal’ of gravitational waves is in fact interference caused by galactic dust.
“When we first detected this signal in our data, we relied on models for Galactic dust emission that were available at the time,” said John Kovac, principal investigator of BICEP2 at Harvard University, Cambridge, Mass. “These seemed to indicate that the region of the sky chosen for our observations had dust polarization much lower than the detected signal.”
“This joint work has shown that the detection of primordial B-modes is no longer robust once the emission from Galactic dust is removed,” added Jean-Loup Puget, principal investigator of the HFI instrument on Planck at the Institut d’Astrophysique Spatiale in Orsay, France.
“So, unfortunately, we have not been able to confirm that the signal is an imprint of cosmic inflation.”
We will have to wait to read the full details behind this latest twist in the BICEP2 results when the joint Planck-BICEP2 paper is published next week, but it seems certain that the original BICEP2 announcement was premature.
It is important to note, however, that this null result doesn’t disprove the existence of gravitational waves, it just confirms, to a high degree of certainty, that BICEP2 hasn’t detected gravitational waves — yet.
“While we haven’t found strong evidence of a signal from primordial gravitational waves in the best observations of CMB polarization that are currently available, this by no means rules out inflation,” said Reno Mandolesi, principal investigator of the LFI instrument on Planck at University of Ferrara, Italy.
Read more at Discovery News
The detailed model reveals a bubble-like interior of debris that connects with a bright shell of ejecta arranged in multiple circular structures.
"This is the first time we've actually seen such a complete image of what the interior of this thing looks like," said one of the study's authors Professor Robert Fesen of Dartmouth College in New Hampshire.
"It shows big bubbles, big cavities that others suggested might be there, and this shows they really are."
The study is published in the journal Science.
Cassiopeia A was created 340 years ago when a massive star exploded to form a neutron star, making it a good subject for a cosmic post mortem.
In this type of explosion, known as a core-collapse supernova, the outer layers of the star drop in free fall, reaching speeds of 70,000 kilometers per second, a significant fraction of the speed of light.
Somehow, that material suddenly stops and ends up traveling the other way at up to 10,000 kilometers per second. Scientists call this sudden reversal a "bounce", but until now they've been unsure exactly how it happens.
"We know the core collapses down to form a neutron star, and the rest blows up somehow after that," said Fesen. "But most of our models have had problems blowing up stars because the outer layers of the star collapse into the core and smother the explosion!"
Distant supernovae outside our galaxy are difficult to study because they're so far away.
Fesen and co-author Dr Dan Milisavljevic, of the Harvard-Smithsonian Center for Astrophysics, used near-infrared spectroscopy to measure expansion velocities of extremely faint material inside the supernova remnant, providing the crucial third dimension for the 3D model.
"We're sort of like bomb squad investigators," said Milisavljevic. "We examine the debris to learn what blew up and how it blew up. Our study represents a major step forward in our understanding of how stars actually explode."
The study revealed that cavities in the supernova's interior are caused by plumes of radioactive nickel 56, said Fesen.
"Nickel 56 will eventually decay into iron, and during that decay process a lot of energy is generated. These plumes of nickel move through the non-radioactive material, pushing it away and making cavities.
Read more at Discovery News
Between 100-200 million years ago, when dinosaurs roamed Earth, NGC 7714 got too close to another galaxy (NGC 7715, out of frame, right) and the extreme tidal forces dragged one of its once-elegant spiral arms deep into intergalactic space. The scattered stars now form a stellar bridge to the second galaxy, exchanging star-forming material.
Both galaxies are approximately 100 million light-years from Earth.
This violent galactic collision wasn’t all bad news for NGC 7714, however. The encounter caused disruption in the interstellar gasses it contains, triggering a wave of new star formation throughout the galactic spirals. The wave of star birth has been captured as bright blue by Hubble’s optics.
Due to the frenzied birth of new stars, astronomers refer to NGC 7714 as a Wolf-Rayet starburst galaxy. Many of the young, massive stars are known as Wolf-Rayets, which as very massive, hot, tumultuous stars that live fast and die young, shedding huge quantities of superheated gases before they erupt as supernovae.
From Discovery News
|A threadsnake on its way to the arcade. Do arcades even exist anymore? Let’s say they do, otherwise this caption won’t make sense. Well, come to think of it, this caption doesn’t make sense regardless.|
But what if your wildly irresponsible father hadn’t just left a shrink ray lying around—what if instead evolution had over the millennia shrunk you down, bit by bit, until a beetle seemed a formidable foe? For an answer to that, you’d have to ask the smallest snake in the world, the Barbados threadsnake, which isn’t even recognizable as a serpent anymore. It’s 4 inches long, about as thick as spaghetti, and looks more like a worm than a snake. And the challenges its diminutive size brings are many—save for falling into cereal bowls, of course.
First of all, there’s the matter of feeding. According to Temple University’s S. Blair Hedges, who first described the creature in 2008, the Barbados threadsnake has “a pretty narrow diet because their mouth can barely open. I mean, they’re small to begin with, but then their mouths don’t open like a normal snake. They just barely open up enough to squeeze in a little microscopic insect.”
|A threadsnake post-arcade.|
Threadsnakes are burrowers, spending their days squirming through soft soil, and that may be due in part to another problem that small creatures face. Because the extremely thin snake has a higher ratio of surface area to volume—compared to, say, a polar bear, which has a lower ratio with its bulky body—it’s more susceptible to losing moisture. By kicking back in the wet dirt, the snake can better avoid desiccation (being so bulky, by the way, also helps the polar bear better retain heat).
Also an issue is how they bear their own young. How many eggs a snake can lay varies greatly, the Eastern mud snake here in the States, for instance, can produce as many as 100, but the threadsnake is at the opposite end of the spectrum with a grand total of…one. Mama threadsnake bets on one single egg.
|The Western blind snake, Leptotyphlops humilis (which shares a genus with the Barbados threadsnake), and her highly elongated eggs. It’s pink because that’s in style right now.|
This is an extreme evolutionary tradeoff. By growing so small, the threadsnake has sacrificed high fecundity, that is, how many young it’s able to produce. This is of course rather risky. We humans having a single child is one thing, since we stick around to dotingly care for it for a long, long time (well, ideally at least). But most reptiles lay their eggs and just take off. Yet here we have a tiny snake that’s been getting along perfectly fine dropping just one egg. Problem is, its life history as a whole and its ecology remain very much mysterious. For all we know the females could actually stick around and guard their hatchling like some species of reptile do. “We know almost nothing about these because they’re so rare,” said Hedges. “There’s only a few specimens that have ever been seen and collected. Nobody’s ever studied them ecologically.”
But we can be sure that there’s a very good reason why the threadsnake got so tiny: shrink rays. Wait, no. Not shrink rays.
Little Big Planet
When an island forms, it’s ripe for conquering. Plants and animals get there any number of ways: swimming, floating on debris after a hurricane, flying, blowing in the wind (spiders can float hundreds of miles by sending out silk that gets caught up in gusts). And when the first creatures arrive, they find a whole lot of open jobs in the ecosystem just asking to be taken, known as niches. And those new jobs aren’t necessarily the ones the critters had back on the mainland. This may have been what happened to the threadsnake. “This species, even though it’s a snake,” said Hedges, “it could be filling a niche of a smaller invertebrate like a centipede or something like that on the mainland.”
|God I hope this was a first date. How weird would that be. “Hey, you wanna check out a model of titanoboa, which, at nearly 50 feet long, was the largest snake to ever live?” *silence* “OK, but why are you talking like that?”|
Read more at Wired Science
Jan 29, 2015
Baleen whales, the largest animals on Earth at about 65 to 80 feet long, can emit vocalizations at very low frequencies, at wavelengths sometimes longer than the whales themselves. But how they hear, has remained to scientists a bit of a puzzle.
Rather than use more traditional whale-hearing analysis -- relying on anatomic study and sound-playback experiments with whales in controlled environments -- two researchers from San Diego decided to use computational horsepower and 3D software to tackle the problem.
San Diego State University biologist Ted W. Cranford and University of California, San Diego engineer Petr Krysl created a three-dimensional computer model of a baleen whale's head, one that would include the skin, skull, eyes, ears, tongue, brain, muscles, and jaws.
For their test subject, the pair obtained the head of a fin whale that beached in 2003 and then ran it through an X-ray CT scanner.
Once they had the head scan, Cranford and Krysl ran simulations of how sound travels through the whale's brain. To get the detail they needed, they used a technique called finite element modeling, in which the data representing the head parts and skull were separated out into tiny elements by the millions, the relationships between the elements tracked.
Sound can reach a baleen whale's ear bones on its skull in two ways: the sound's pressure waves can go through the animal's soft tissue; or the sounds can vibrate along the skull itself, in a process called "bone induction."
The problem with the soft-tissue, pressure, route, the researchers said, is that it's ineffective when sound waves are longer than the whale's body. But with the bone induction process, those longer waves become amplified as they vibrate in the creature's skull.
The scientists' computer modeling showed that the bone induction process was about four times more sensitive to low-frequency sounds than the soft-tissue, pressure mechanism.
What's more, their modeling predicted that bone induction is 10 times more sensitive to the lowest frequencies used by fin whales (10 Hz-130 Hz).
Read more at Discovery News
The mummified body, which was covered in animal skin, has been sitting in the lotus position for about 200 years.
According to the report, no information is so far available as to where the body was found.
“The only details we learned was that it was covered with a cattle skin,” the newspaper wrote.
Researchers at the Ulaanbaatar National Centre of Forensic Expertise are now analyzing the remains.
According to The Siberian Times, experts are speculating over whether the mummy is a “teacher of famous Lama Dashi-Dorzho Itigilov,” a Buddhist Lama of the Tibetan Buddhist tradition who was born in 1852.
Itigilov also died while meditating in lotus posture and was buried in 1927 in that position, his remains laid to rest in a pine box. When he was exhumed in 1955 and in 1973, astonished monks found the body in near-perfect condition and still sitting upright.
From Discovery News
Netflix has spent tens of millions of dollars on the show, touted as its answer to HBO's huge hit Game of Thrones. With swashbuckling sword fights, mass battles, intricate costumes and palace plots, the series portrays conflicts and rebellions in the Mongol empire under Kublai Khan, as seen through Marco Polo's eyes.
Kublai, the grandson of the great Mongol conqueror Genghis Khan, was a phenomenal warrior himself, reigning from 1260 to 1294, subjugating swathes of China and establishing the Yuan dynasty of Chinese emperors.
Mongolian viewers were excited to see one of their own being cast as Kublai's brother Ariq Boke and hearing the occasional Mongol phrase, despite most leading roles going to Chinese actors or those of Chinese descent, such as Briton Benedict Wong, who plays Kublai.
But according to Mongolian historians, much of the plot plays fast and loose with the facts.
Batsukh Otgonsereenen, who spent 10 years researching his book The History of Kublai Khan, told AFP: "From a historical standpoint 20 percent of the film was actual history and 80 percent fiction."
The fate of Ariq Boke, who briefly took power following the death of their father but lost the subsequent civil war, was particularly twisted, he said.
"The part where Kublai and Ariq Boke fight to a bloody death in front of their soldiers is completely untrue," he said. "Yes, Ariq did try to seize the throne, but in history Kublai and Ariq resolve their issues."
A concubine-assassin supposedly sent by a minister of the rival Song dynasty to seduce Kublai and kill his queen was another fantasy.
"Mongolian Khans never wed or had concubines that were totally unknown," said Otgonsereenen. "Kublai also did not live in a palace. He lived in his royal ger in Beijing, in a traditional Mongolian manner."
In a press release, Netflix described the series -- shot in Kazakhstan, Malaysia and Italy, rather than Mongolia or China -- as set in a world "replete with exotic martial arts, political skullduggery, spectacular battles and sexual intrigue."
But Otgonsereenen said the creators' research on Kublai seemed "very sloppy."
"I think they tried to show Mongolian history like Game of Thrones with conspiracy, betrayal, blood and sex," he said. "Mongolian youth who watch this series might get the wrong impression of Kublai Khan being quite cruel and perverted."
- Big in the Middle Ages -
Polo -- played by Italy's Lorenzo Richelmy in the show -- was a Venetian merchant who spent more than two decades in central Asia and China with his father and uncle, serving for years as Kublai's minister and envoy.
After his return the story of his journeys, "Book of the Marvels of the World," also known as The Travels of Marco Polo, propelled him to medieval superstardom.
But U.S. critics panned the show, with news site vox.com's reviewer writing: "This is a show about Kublai Khan that doesn't realize it's about Kublai Khan because Marco Polo has better name recognition.
"Is it worth watching?" he asked rhetorically. "Eh, not really, no."
The series, released last month, has a 30 percent rating on review aggregator rottentomatoes.com, which describes it as "an all-round disappointment."
Nonetheless a second season has been commissioned.
- Neighborly tensions -
Some Mongolian viewers praise the series, and many welcome the space it gives their remote country on the global small screen.
Orgil Narangerel, who played Genghis Khan in a BBC documentary, said it was more accurate than any previous foreign portrayal of Mongolian culture.
"As a Mongol and an artist, 'Marco Polo' makes me feel like our dreams are coming true," he told AFP. "I watched all 10 episodes in just in one day.”
Read more at Discovery News
NASA's next Earth-observing satellite is ready to launch Friday (Jan. 29), and it could vastly improve the way scientists monitor droughts around the world.
Originally scheduled to launch on Thursday, the space agency's Soil Moisture Active Passive satellite (SMAP) is now scheduled to launch from California's Vandenberg Air Force base atop a United Launch Alliance Delta II rocket at 9:20 a.m. EST (6:20 a.m. PST) on Jan. 30, and at the moment, weather is looking good ahead of liftoff.
The SMAP satellite is designed to measure the moisture of Earth's dirt more accurately than ever before, according to NASA. The probe will make a global map of the planet's soil moisture levels every three days. This measurement is important because it can help scientists create more accurate weather models, learn more about drought conditions and even predict floods, NASA officials have said.
"What the soil measurements will do is improve our weather forecasts, improve our assessments of water availability and also address some issues dealing with long-term climate variability and assessments of the impact of human intervention in the global environment," Dara Entekhabi, SMAP science team leader, said during a news conference Tuesday (Jan. 27). "All of these come together and it's the metabolism, how it responds, just like a human body."
You can watch live coverage of the SMAP satellite launch starting at 7 a.m. EST Friday (Jan. 30) on Space.com via NASA TV.
The SMAP probe comes equipped with a huge mesh antenna, expected to be deployed sometime after launch. At nearly 20 feet (6 meters), the antenna is the largest of its kind that NASA has ever flown in space, officials have said. SMAP's antenna is designed to spin at about 14.6 revolutions per minute while mounted to the end of a long arm on the satellite's body.
The satellite is built to measure moisture in the top 2 inches (5 centimeters) of soil from its spot in orbit about 426 miles (685 kilometers) above Earth's surface, completing an orbit once every 98.5 minutes. The satellite's unprecedented soil information could help scientists learn more about how droughts spread and the places where they occur. By knowing the moisture in topsoil ahead of time, it could also help researchers better-predict where floods will happen.
"Soil moisture is a key part of the three cycles that support life on this planet: the water cycle, the energy cycle and the carbon cycle," NASA SMAP program executive Christine Bonniksen, said during the news conference. "These things affect human interest: flood, drought, disease control, weather."
Read more at Discovery News
M-type red dwarf stars possess two qualities that are usually considered too harsh to nurture habitable exoplanets: extreme tides and violent space weather.
As the star is smaller, its habitable zone is more compact, so any potentially habitable world would have to orbit very close to its star. Orbiting so close would induce extreme tides on this world, likely rendering it barren and sterile.
“This is the reason we have ocean tides on Earth, as tidal forces from both the moon and the sun can tug on the oceans, creating a bulge that we experience as a high tide,” said Rodrigo Luger, of the University of Washington, lead author of a paper published in the journal Astrobiology. “Luckily, on Earth it’s really only the water in the oceans that gets distorted, and only by a few feet. But close-in planets, like those in the habitable zones of M dwarfs, experience much stronger tidal forces.”
These tidal forces would physically warp the planet’s crust, driving extreme tectonic activity and volcanism, possibly triggering a runaway greenhouse effect, vaporizing any surface water. Tidal locking — where one hemisphere continually faces the star — would also be a problem.
M-type red dwarfs are also known to have extreme space weather, and any planet orbiting within the star’s habitable zone would bear the brunt of powerful stellar flares and strong stellar winds. This irradiated environment would ultimately erode any surviving atmosphere away, blowing it into space.
But what’s bad for an Earth-like exoplanet may not be so bad for a mini-Neptune, which sports a thick atmosphere during formation.
Mini-Neptunes would form far from their host stars, “with ice molecules joining with hydrogen and helium gases in great quantity to form icy/rocky cores surrounded by massive gaseous atmospheres,” writes a UW press release.
“They are initially freezing cold, inhospitable worlds,” Luger said. “But planets need not always remain in place. Alongside other processes, tidal forces can induce inward planet migration.”
Inward migration would cause the mini-Neptune to be exposed to the stellar blowtorch and, over millions of years, the mini-Neptune’s atmosphere would be blown away. Once lodged in the star’s habitable zone, the mini-Neptune’s hydrogen-free core may be left behind; objects called “habitable evaporated cores” or HECs.
“Such a planet is likely to have abundant surface water, since its core is rich in water ice,” said Luger. “Once in the habitable zone, this ice can melt and form oceans.”
For these HECs to become anything remotely ‘habitable’, a very delicate balance of atmospheric chemistry and radiation from the star would be needed. But in some models, oxygen-rich atmospheres are possible, incubating liquid water on the rocky surface.
Whether or not such a planet could host any kind of life remains open to debate. One could imagine that if an HEC evolves with a powerful magnetosphere, the worst stellar storms may be deflected. As for the problems with the extreme red dwarf tides, the world may well be tidally locked, where one side of the planet may be inhosptable, but powerful weather systems whip around the planet, creating the most extreme biosphere imaginable where life thrives in isolated regions.
Read more at Discovery News