{ http://www.sciencealert.com/ }

21-11-2017 om 22:32 geschreven door peter  

8,000 years old rock art in Saudi Arabia documents the earliest known use of dog leashes

BY ALEXANDRU MICU

Two ancient sites in Saudi Arabia have revealed an unexpected surprise, a new paper reports — the oldest known recording of dogs put on a leash. The 8,000-year-old images are etched into rock and depict humans and dogs working together in hunts before the widespread emergence of agriculture.

The carvings were discovered by Maria Guagnin, an archaeologist at the Max Planck Institute for the Science of Human History, at two rock-art sites in northwestern Saudi Arabia, Shuwaymis and Jubbah. The images, estimated to be around 8,000 years old, depict humans and dogs hunting side by side, and suggest that the two species were already ‘friends’ before farming took hold.

The locations of Shuwaymis (bottom left) and Jubbah (bottom right).
Image credits Guagnin, M. et al., 2017, Journal of Anthropological Archaeology.

The two sites “contain the best and oldest examples of Neolithic rock art,” Saudi-Archaeology claims, adding that the region used to be rich “with people, flora, and wildlife” in the past. Those people left behind thousands of panels of rock-art showcasing their lives, society, and hunts, which Guagnin was documenting when she stumbled upon the unusual scenes.

Overall, she counted 156 depictions of dogs at Shuwaymis and 193 at Jubbah. The animals resemble today’s Canaan breed in appearance, Guagnin adds, with pricked ears, curled tails, and short snouts. They’re most often depicted helping bow-wielding human hunters take down prey including lions, ibexes, gazelles, or horses. The animals are clearly distinct from the hyenas and wolves depicted in other panels, Guagnin and her co-authors write.

Image credits Guagnin, M. et al., 2017, Journal of Anthropological Archaeology.

Comparison between the Canaan breed and the dogs on the rock art panels.

Image credits Guagnin, M. et al., 2017, Journal of Anthropological Archaeology.

From what we know so far, dogs were domesticated from an ancestor of today’s gray wolf between 40,000 and 15,000 years ago. There’s still a lot of unknowns (and thus, room for debate) about how and where this domestication process took place, and how early humans and dogs interacted and co-existed. The panels described by Guagnin’s team will help to guide these discussions in the future. The images haven’t been directly dated so far, but the team estimates they date back between 8,000 and 9,000 years ago, to the pre-Neolothic era, before farming took root in the region.

The most interesting find, however, was that some of the hunting dogs taking seem to be leashed. The art depicts these dogs as tethered to the waist of hunters, quite the smart hack when you need two free hands to shoot arrows. It hasn’t been established why these dogs were leashed, but the team speculates that they may have been young dogs still undergoing training, old ones that could be injured in the thick of the hunt, or scent dogs that were too valuable to risk.

Image credits Guagnin, M. et al., 2017, Journal of Anthropological Archaeology.

“This suggests not only are some human populations controlling their hunting dogs by the Pre-Neolithic, but that some dogs may perform different hunting tasks than others,” the paper explains.

“Some may be used only to track prey scents, while others are used to corral and attack prey, protect human hunters, or help haul meat back to camp.”

The hunting scenes represent the earliest known evidence of dog leashes in the archaeological record worldwide, the study claims. Furthermore, they push back the presence of domesticated dogs on the Arabian Peninsula to much earlier than we’d believed. Previously, the oldest dog remains found on the whole peninsula hailed from the 4th millennium B.C. in today’s Yemen, some 2-3 thousand years younger that the estimated age of the Shuwaymis and Jubbah panels.

The paper, “Pre-Neolithic evidence for dog-assisted hunting strategies in Arabia” has been published in the Journal of Anthropological Archaeology.

{ https://www.zmescience.com/ }

21-11-2017 om 22:21 geschreven door peter  

Scientists ‘reclone’ world’s first cloned dog

BY TIBI PUIU

Ever since scientists cloned the first animal, a sheep named Dolly, one important question on everyone’s mind was whether or not a clone can expect a poorer health. This is still an open question, one that South Korean researchers hope to settle in time. They’ve essentially cloned a clone, using cells from the world’s first cloned dog, an Afghan hound named Snuppy.

The three surviving reclones of ‘Snuppy’ at 2 months of age.

Credit: Scientific Reports.

Theoretically, a clone is a carbon copy of the original organism, with the two sharing identical genes. The science of cloning, however, is still in its infancy and there are many loose ends that we might be missing. There is a possibility that the cloned individual might carry certain abnormalities, and may have a shorter life expectancy. Another concern is that cloned individuals might retain the age of the donor’s gene, seeing how genes change with age. 

Clones of clones

Dolly the sheep died at age six, which raised concerns that cloned individuals might not be entirely healthy. The sheep appeared to age faster than normal and suffered from osteoarthritis in her knees and hips at an early age. But a follow-up study of 13 cloned sheep — including four derived from the same DNA strand as Dolly– concluded that there didn’t seem to be any evidence that indicates cloning has any long-term health effects. “They’re old ladies,” said Kevin Sinclair, a developmental biologist and lead author of the study of the 2016 study published in Nature Communications. “They’re very healthy for their age,” he added.

Scientists at the Seoul National University, South Korea, are now also investigating the health of ‘clones of clones’, this time in dogs. Snuppy, became the world’s first cloned dog in April 2005. He was cloned from the cells belonging to an Afghan hound called Tai who lived to be 12 years old and died of cancer. Snuppy lived 10 years and also died of cancer but a different kind. Afghan hounds live to be 11.9 years on average and dogs commonly die of cancer so there’s really nothing unusual about either dogs, donor or clone.

The team led by Min Jung Kim used stem cells collected from Snuppy when the dog was five years old. The scientists then employed somatic cell nuclear transfer (SCNT) to insert Snuppy’s cells into eggs collected from female dogs whose nuclei were removed. A total of 94 embryos were created which were then implanted into surrogate mothers. The success rate was 4.3 percent leading to four live births of ‘reclones’. That might seem really low but take a minute to consider that during the time Snuppy was first born (let’s call him ‘Snuppy Mark 1’), the success rate was only 0.2%.

One of the four reclones died within a few days from birth due to diarrhea while the other three grew to be nine months old when the Kim and colleagues drafter their paper, now published in Scientific Reports. They’re still alive and well, seemingly healthy. The dogs will be closely monitored in the years to come.

“With the data from Tai and Snuppy in hand, we are excited to follow the long-term health and aging processes of these second generation of clones and work with them to contribute to a new era of studying longevity of cloned canines and given the history of both Tai and Snuppy they may also provide potential insights into the development of cancer,” the authors concluded.

{ https://www.zmescience.com/ }

21-11-2017 om 22:09 geschreven door peter  

2,000-Year-Old Water Is Locked in the Ocean's 'Shadow Zone, Say Scientists

This ancient layer hasn't moved for centuries.

By Yasmin Tayag

Thousands of feet below the crashing surface of the North Pacific ocean, there’s a dark place where the water stands still. Scientists call it the Shadow Zone, and they’re not just being dramatic. In a recent Nature article, an Australian team of researchers point out that this lightless region of the abyssal ocean has trapped the same water for 2,000 years.

The reason, they report in their paper, can be found even deeper in the sea.

For a long time, scientists had been aware of the existence of the ancient water, but it was never clear why and how it managed to stay still for so long while the ocean above it rolls around so violently.

“Carbon-14 dating had already told us the most ancient water lies in the deep North Pacific,” said lead author and University of New South Wales oceanographer, Casimir de Lavergne, Ph.D., in a statement. “But until now we had struggled to understand why the very oldest waters huddle around the depth of 2 km.”

They realize now, after an analysis of the ocean topography in that area, that the Shadow Zone’s specific depth and location are determined by the slopes and crags of the sea floor below it. According to the scientists, the Shadow Zone is a roughly rectangular patch of especially deep ocean stretching 3,700 miles from east to west and 1,200 miles north to south — making its surface area slightly larger than Europe’s — and the floor beneath it is especially rough.

This uneven floor, coupled with the way that shallower wind-driven currents running above the Shadow Zone move, has sandwiched the ancient water in its stratified position for at least 1,500 years, the researchers write. The shape of the floor prevents water at the very bottom of the sea from rising any further than 1.5 miles below the surface, effectively creating another watery floor. All the water above that layer is largely undisturbed — it’s far enough from the geothermal heat vents that promote mixing — leading to the eerily still Shadow Zone.

It isn’t just water that’s in the Shadow Zone, the researchers point out, noting that the trapped molecules could have major effects on the ocean and even global climate when it eventually does escape.

“When this isolated shadow zone traps millennia old ocean water it also traps nutrients and carbon which have a direct impact on the capacity of the ocean to modify climate over centennial time scales,” read a statement from Stockholm University co-author Fabien Roquet, Ph.D.

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If you liked this article, check out this video about underwater drones for exploring ocean life.

Photos via Flickr / NASA Goddard Photo and Video,

Credit: Fabien Roquet and Casimir de Lavergne, Flickr / marfis75

21-11-2017 om 22:01 geschreven door peter  

21-11-2017 om 18:34 geschreven door peter  

For the First Time, a Robot Passed a Medical Licensing Exam

 

Getty Images

21-11-2017 om 18:24 geschreven door peter  

Sight Unseen: Advanced Imaging Will Solve the Greatest Mysteries of the Human Body

by Abby Norman  

 

Getty Images

An Inside Look

If you’ve ever landed in the emergency room with a broken bone, fallen and hit your head, or been pregnant, then you already know how important medical imaging technology can be. If you’ve been diagnosed with appendicitis, a stroke, or any kind of tumor, those scans may have saved your life.

While medical imaging technology has given us the power to “see” inside the body, the tools of tomorrow will be more powerful still. The science behind this technology has evolved by leaps and bounds in the last few decades, but in order to apply those innovations to medical equipment, researchers need support.

If progress in this area has been slow, it hasn’t been for lack of ideas — it’s been a lack of funding. Now, there are signs that this might be changing, and researchers can already envision the implications of giving medical professionals better ways to see in the body. To do so would change more than the future of medicine: It would irrevocably change how we see ourselves.

Sight Unseen — Today

For centuries, the only way to see inside the body was through exploratory surgery, which has always come with risks — like an infection, hemorrhaging, and so on

Then, in 1895, Wilhelm Roentgen discovered X-rays, giving physicians a tool that could let them “see” the human skeleton without a single incision. And X-rays were only the beginning. Computed tomography (CT) scans take several X-rays and combine them to form a composite image, providing a more detailed internal view of organs, tissues, and bone. Positron-emission tomography (PET) scans identify changes at the cellular level: After a patient ingests a radioactive tracer, the scan tracks it as it moves through the body. This can be helpful not just for diagnosing a disease, but monitoring one that may progress, like metastatic cancer.

While these scans are essential to the practice of medicine, they aren’t without risk — even a simple X-ray exposes patients to a small dose of ionizing radiation, which can build up and pose health risks over time. So medical professionals do their best to use the scans sparingly.

In some cases, medical professionals can use other imaging techniques that don’t require any radiation at all. Ultrasounds, for example, use high-frequency sound waves to produce images of organs within the cavities of the body. They’re useful to help doctors diagnose conditions like ovarian cysts and gallstones. Inserting a catheter or gastrostomy tube becomes easier when the technician can guide them in via ultrasound. Of course, ultrasounds are most often associated with pregnancy, as they are used to construct real-time images of the fetus.

The downside, however, is that the images that ultrasounds produce aren’t particularly high-quality. The lack of detail means that, while an ultrasound might be able to detect a structure on or near the ovary, differentiating between a malignant tumor and a simple cyst usually requires imaging at a higher resolution or even a biopsy. The quality of the ultrasound image also varies depending on the skill of the sonographer, which could make the images less reliable, which could be a life-threatening issue.

While collectively these techniques have informed how doctors treat patients, there’s one technique that stands out above the rest: Magnetic Resonance Imaging (MRI). The MRI can provide a glimpse at the tissues and organs of the entire body, and it’s one of the best ways to take images of the brain.

First developed in the 1970s, MRIs use a combination of radio waves and magnetic fields to render images of our internal organs, soft tissues, bones, ligaments, and cartilage. The human body is full of proton-containing water molecules which will align when exposed to a magnetic field. They flip-flop at different rates depending on what tissues of the body they happen to be in. That’s how the MRI generates an image in which organs are (more or less) distinct from one another.

While MRIs are useful for finding abnormalities in blood flow within the brain, a close relative, functional magnetic resonance imaging (fMRI), can provide insights into the activity of cells in the brain.

And that, we suspect, is where many of the unsolved mysteries of the human body begin.

Much More to See

Research into medical imaging technology receives less attention than you might expect, even though patients benefit greatly (and very often their lives depend upon) this research. Less than two percent of grants from the National Institutes of Health are awarded to academic radiology departments, Richard Ehman, a diagnostic radiologist and director of the Mayo Clinic Advanced Medical Imaging Technology lab, told Futurism.

As it stands today, modern medical imaging methods are extremely useful for clinicians, so rather than devising new techniques, most researchers’ energies have been dedicated to refining existing techniques. In an interview with Nature, Roderic Pettigrew, the director of the National Institute of Biomedical Imaging said that today’s MRI machines are so specific that they can “track the diffusion of water molecules in the brain with such precision that you can compute their trajectories along fibre pathways,” giving physicians more information to better diagnose, monitor, and treat a number of neurological conditions.

The most cutting-edge MRI machines are found in research facilities, but that’s not what you’d find at your local hospital. As healthcare systems struggle under pressure to cut costs without compromising the quality of patient care, entire radiology departments languish and lag. Replacing an MRI machine is pricey, so it’s easy to understand why hospitals are using older models. Some US hospitals still use film.

“Most physicians would have a hard time imagining how they would take care of patients without these tools,” Ehman, of Mayo, said.  While it’s unlikely that any Western medical practitioners lack the capability to take basic images of the body, complacency and a lack of research attention to new imaging techniques have hampered innovation. Stagnation is preventing us from seeing more.

And there is so much more to see.

All the Better to See You With

Over the past 30 years, the design of MRIs has evolved to be faster, quieter, and more powerful — in large part because computer processors have gotten faster. Their evolution is far from over, and a team at the University of California Berkeley has set out to prove it. The team, composed of physicists and engineers, was recently awarded a $13.43 million BRAIN Initiative from the National Institutes of Health to develop the next generation of fMRI, dubbed the NexGen 7T, by 2019.

A MRI machine’s strength is measured in Teslas (T), which indicates the power of a magnetic field. When the magnetic field of our body (the tissues of which contain positively-charged water molecules) interacts with the magnetic field of the MRI, the tissue gives off a signal. The higher the power of the external magnet, the higher the intensity of that signal — and in turn, the higher the resolution of the images the MRI produces. Today, the world’s strongest MRI machines (which are generally isolated in research facilities and academic medical centers) are somewhere between 7T and 10T. Those that are most routinely used for patient care are much less powerful, clocking in at either 1.5T or 3T. Machines of that resolution are decently fast and accurate, good enough for most routine diagnoses: at 3T, an MRI can detect very small lesions in the brains of patients with multiple sclerosis, which a less powerful machine could miss.

But what if MRIs could allow us to go deeper, to see more — and to do so with breathtaking clarity? What could we glean about the progression of a neurodegenerative disease like multiple sclerosis (MS) if we could see nerves lose their protective myelin in real-time? If we could see the structures of the brain in greater detail, what could we learn about depression, anxiety, schizophrenia, or autism? If we could clearly see every nook and cranny, down to the axons and neurons, could observe the brains’ many processes as they happened, could we finally solve what some philosophers have called the “hard problem of consciousness?”

To inch us closer to doing so, researchers at UC Berkeley will need to achieve “a total redesign of nearly all of the [MRI] scanner components, not just an incremental change,” team lead David Feinberg said in the press release announcing the grant.

Another pair of researchers from UC Berkeley recently devised a way to make MRIs more safe and effective for children — a longstanding problem in the field. A physicist, electrical engineer, and a radiologist teamed up to create 3D-printed, flexible coils that fit onto garments. The resulting images were also remarkably crisp, which would benefit adults, too. Now the team is working with GE to further develop its design, possibly making up part of the next generation of MRI coils.

The applications for advanced imaging techniques go beyond our current uses. As Ehman noted, there are a number of measurements clinicians need to assess through the course of diagnosing and treating their patients. One example is that of measuring pressure within the human body. Getting these readings can require invasive, uncomfortable procedures, such as a spinal tap, that come with their own risks. As medical imaging once cut down the need for surgery, perhaps one day it could eliminate the need for needles, gauges, cuffs, and catheters.

Better imaging could also help us see elements of our own biology we never even knew existed. Invariably, more answers lead to more questions. And that will likely inform the path of medical research for decades to come.

Other innovations in medical imaging may be a bit more dazzling to the average patient. At Massachusetts General Hospital, physicist Matthew Rosen is leading research into the clinical tools that are often paired with MRI machines, such as contrast dyes. His team is developing synthetic, biocompatible nanodiamonds that could replace contrast agents that are traditionally metal-based.

“Nanodiamonds have the potential to revolutionize the field of molecular imaging,” Rosen said in a press release, adding that their tiny size could enable radiologists to track any process at the cellular and subcellular level.

The team has only conducted lab-based tests and haven’t yet figured out how to best introduce the nanodiamonds into the human body (possible routes, as with any tracer, would include ingestion, infusion, or injection), according to a study Rosen and his team published in Nature Communications in March. There’s a long way to go before patients will have the option of taking a shot of medical-grade bling.

Technological progress made over the past century has transformed how we work, how we socialize, and how we date. The same goes for medicine, and for medical imaging in particular. That progress seems poised to continue — advanced computing, artificial intelligence, automation, and deep learning will improve medical technologies involved in everything from scans to surgery.

“I think that, in the future, we may look back at this time and it will seem that we were making very limited use of our best imaging technologies,” Ehman said (there are many complex reasons for this, he noted, including limited federal funding and the challenges of implementing new healthcare technologies). But Ehman remains hopeful that, despite these challenges, the future of medical imaging technology will transform medicine once again. Perhaps we can’t count on a renaissance, but having crystal clear vision will no doubt supply a few answers — and we should stay eager to be dazzled by them.

Disclaimer: the editor of this piece was a recipient of the Mayo Clinic’s 2017 journalist residency for surgery, which connected the author to sources quoted in this piece. The residency was paid for by the Mayo Clinic; however, neither the clinic nor any of its affiliates have editorial review privileges.

{ https://futurism.com/ }

21-11-2017 om 18:17 geschreven door peter  

Here's What a Volcano on Mars Looked Like to Mariner 9 in 1971

21-11-2017 om 17:53 geschreven door peter  

Oumuamua : nouvelles données

Sur spaceweather.com

Peu à peu les données sur l'objet 1I/2017 U1 s'affinent. Le JPL publiait hier une nouvelle page remarquable :

https://www.jpl.nasa.gov/news/news.php?feature=7006

L'objet a une forme de cigare et mesure dans les 400 m. La forme est très allongée, avec un ratio L/l de 10 à 1, des proportionsjamais observées à ce jour pour un astéroïde. Il serait rocheux mais aussi en partie métallique. Il tourne sur son axe en 7 h et sa brillance varie d'un facteur 10, phénomène jamais constaté non plus auparavant pour des objets célestes naturels. Il est de couleur rougeâtre, peut-être due à une longue irradiation par les rayons cosmiques.
Il se confirme que l'origine de son voyage n'est pas la région de Véga, celle-ci s'étant trouvée dans une position très éloignée lorsque l'objet se trouvait dans ses environs (actuels) il y a 300 000 ans. Il est aussi confirmé qu'il a été accéléré par effet de fronde (slingshotted) au voisinage immédiat du Soleil, passant de 26.4 à 87.3 km/s (314 000 km/h).
Paul Chodas, du JPL, traduisant en cela l'immense surprise de la Communauté astronomique, le décrit comme "un étrange visiteur venu d'un lointain système stellaire, ne ressemblant à rien de ce qu'on ait jamais vu au voisinage du nôtre".

Ainsi, les caractéristiques de 1I/2017 U1 font de lui un objet extraordinairement singulier. Il est clair qu'on peut imaginer n'importe quoi quant à sa véritable nature. En tout état de cause, il ne s'y serait pas pris autrement s'il avait délibérément visé le Soleil pour l'utiliser comme un tremplin gravitationnel ou, qui sait, comme une source d'énergie. Nous ne le saurons probablement jamais. On ne peut malgré tout se retenir d'un clin d'oeil, "les Raméens font tout par trois".

{  spaceweather.com }

21-11-2017 om 17:43 geschreven door peter  

First Interstellar Visitor From another Solar System Dazzles Astronomers

It is the first observed Alien object from another solar system, according to a study in the journal Nature. Preliminary calculations suggest that the alien visitor came from the approximate direction of the bright star Vega, located in the northern parts of the constellation of Lyra.

A recent study has identified the shape of the first alien visitor that astronomers say, has come from another solar system.

Spotted for the first time on October 19 by the University of Hawaii’s Pan-STARRS1 telescope, funded by NASA’s Near-Earth Object Observations (NEOO) Program, the asteroid named Oumuamua—which is Hawaiian for “a messenger from afar arriving first”—is around 400 meters long and is extremely elongated, making it look like a giant cigar.

This makes the object even more mysterious as astronomers revealed its aspect ratios is much greater than that of any other asteroid or comet that has been observed in our solar system.

In other words, it’s unlike anything we’ve ever spotted.

Astronomers note that its extremely elongated shape (which is surprising) may help provide new clues as to how other solar systems in our galaxy formed.

According to a study published in Nature, the alien visitor has been wandering through the Milky Way Galaxy for hundreds of millions of years.

“For decades we’ve theorized that such interstellar objects are out there, and now – for the first time – we have direct evidence they exist,” said Thomas Zurbuchen, associate administrator for NASA’s Science Mission Directorate in Washington.

“This history-making discovery is opening a new window to study the formation of solar systems beyond our own.”

Immediately after the comet was spotted, many observatories on Earth turned towards Oumuamua to study it.

Combined images from the FORS instrument on the ESO telescope found that Oumuamua varies in brightness by a factor of ten as it spins on its axis every 7.3 hours.

And this is rather odd. Astronomers note how no other known asteroid or comet in our solar system varies so widely in brightness, having such a large ration between its length and width.

“This unusually big variation in brightness means that the object is highly elongated: about ten times as long as it is wide, with a complex, convoluted shape,” said Karen Meech of the Institute for Astronomy in Hawaii. “We also found that it had a reddish color, similar to objects in the outer solar system, and confirmed that it is completely inert, without the faintest hint of dust around it.”

Preliminary calculations suggest that the alien visitor came from the approximate direction of the bright star Vega, located in the northern parts of the constellation of Lyra.

However, astronomers note that it so extremely long for Oumuamua to make the journey that Vega was nowhere near that position when the asteroid was there some 300,000 years ago.

Furthermore, the object which was originally classified as a comet isn’t one after observations from ESO and elsewhere revealed no signs of cometary activity after it slingshotted past the Sun on Sept. 9 at a blistering speed of 196,000 miles per hour (87.3 kilometers per second), notes NASA.

The object was reclassified as interstellar asteroid 1I/2017 U1 by the International Astronomical Union (IAU),

“What a fascinating discovery this is!” said Paul Chodas, manager of the Center for Near-Earth Object Studies at NASA’s Jet Propulsion Laboratory, Pasadena, California. “It’s a strange visitor from a faraway star system, shaped like nothing we’ve ever seen in our own solar system neighborhood.”

{ https://www.ancient-code.com/ }

21-11-2017 om 17:31 geschreven door peter  

NASA STUDY REVEALS OUR SOLAR SYSTEM IS SURROUNDED BY A MASSIVE SPHERICAL ‘SHIELD’

Data from NASA’s Cassini, Voyager and IBEX missions suggest that the solar system is surrounded by a MASSIVE, SPHERICAL shaped magnetic field. In the past, experts thought that the heliosphere was in fact a comet-shaped structure, with a rounded head and an extended tail. But new data covering an entire 11-year cycle of solar activity shows that this may not be the case.

According to scientists, our Sun releases a constant flux of magnetic solar material—called solar wind—that fills the inner solar system, and extends beyond the orbit of Neptune.

Shown in a Hubble Space Telescope image, the “astrosphere” around the star L.L. Orionis approximates the heliosphere around our solar system.

IMAGE COURTESY ESA/NASA

This wind creates something that can be explained as a bubble, some 37 million kilometers wide, called the heliosphere. Our entire solar system, including the H, moves through interstellar space. Just as Earth orbits the Sun, our Sun orbits the galactic center –which from our vantage point is located around 25,00 light years— in an elliptic orbit. It completes a revolution every 225 million years approximately—called a Galactic year.
Anyway, getting back on track, this new discovery calls into question the alternate view of the solar magnetic fields trailing behind the sun in the shape of a long comet tail—almost like a kite. 

Until now, scientists thought that the heliosphere was in fact a comet-shaped structure, with a rounded head and an extended tail. But new data covering an entire 11-year cycle of solar activity shows that this may not be the case: the heliosphere is most likely rounded at both ends, making its shape almost spherical. An article featuring the results of the study was published in Nature Astronomy.

“Instead of a prolonged, comet-like tail, this rough bubble-shape of the heliosphere is due to the strong interstellar magnetic field—much stronger than what was anticipated in the past—combined with the fact that the ratio between particle pressure and magnetic pressure inside the heliosheath is high,” says Kostas Dialynas of the Academy of Athens in Greece, lead author of the study. Interestingly, Cassini—which has explored Saturn for over a decade—using its Magnetospheric Imaging Instrument discovered surprising new data about the shape of the heliosphere’s trailing end, the heliotail.

“Our Cassini instrument was designed to image the ions that are trapped in the magnetosphere of Saturn,” says coauthor Tom Krimigis, of the Johns Hopkins Applied Physics Laboratory, an instrument lead on the Cassini and Voyager missions. “We never thought that we would see what we’re seeing and be able to image the boundaries of the heliosphere.”

Since these particles move only at a small fraction of the speed of light, their trip from the sun to the edge of the heliosphere and back takes quite a lot. Now, when the number of particles coming from the sun changes, it takes years before that is reflected in the amount of natural atoms shooting back into the solar system. As Cassini was orbiting Saturn, its instruments measured the neutral atoms revealed surprising details—the particles coming from the ‘tail’ of our solar system’s heliosphere reflect the changes in the solar cycle almost exactly as fast as those coming from the nose of the heliosphere.

“If the heliosphere’s ‘tail’ is stretched out like a comet, we’d expect that the patterns of the solar cycle would show up much later in the measured neutral atoms,” said Krimigis.

What does this mean? Well, since patterns of solar activity show just as quickly on one side of the heliosphere as the other, it implies that the tail of the heliosphere is around the same distance from us as the nose. In other words, the comet-like tail that scientists thought existed previously may not be there at all, as the heliosphere that wraps the solar system is nearly round. 
Scientists note that a spherical heliosphere may exist due to a number of reasons. First of all, data gathered by the voyager 1 probe shows that the interstellar magnetic field beyond the heliosphere is much stronger than scientists had expected.

“This data that Voyager 1 and 2, Cassini and IBEX provide to the scientific community is a windfall for studying the far reaches of the solar wind,” says Arik Posner, NASA’s Voyager and IBEX program scientist. “As we continue to gather data from the edges of the heliosphere, this data will help us better understand the interstellar boundary that the heliosphere, this data will help us better understand the interstellar boundary that helps shield the Earth environment from harmful cosmic rays.”

{ http://www.sci-techuniverse.com/ }

21-11-2017 om 16:42 geschreven door peter  

Major earthquakes predicted for 2018 due to changes in the Earth’s rotation

According to scientists, the number of severe Earthquakes is likely to rise exponentially in 2018, due to a slowing down of Earth’s rotation. Minimal variations in Earth’s rotation speed could trigger intense seismic activity in 2018, especially in densely populated tropical regions, warn experts.

Although such variations in the rotation of our planet are small, changing the length of the day by one millisecond, these changes could set off a release of large amounts of underground energy.

The connection between Earth’s rotation and seismic activity is displayed in a study by Roger Bilham of the University of Colorado at Boulder and Rebecca Bendick of the University of Montana at Missoula, presented in October during the annual meeting of the Geological Society of America.

“The relationship between Earth’s rotation and earthquake activity is strong and suggests there is going to be an increase in numbers of violent earthquakes next year,” Bilham told the Observer in an interview.

In the study presented by Bilham and, the two argue that by looking at earthquakes of magnitude 7 and greater that had occurred since 1900. “Major earthquakes have been well recorded for more than a century, and that gives us a good record to study,” explains Bilham.

The two researchers discovered five periods in which there were a significantly greater number of large earthquakes compared to other times.

“During these periods, there were between 25 and 30 intense earthquakes a year,” adds Bilham.

“The rest of the time, the average number was about 15 large earthquakes per year.”

Image Credit: Shutterstock

The researchers sought to find correlations between these periods of intense seismic activity and other factors and discovered that when the Earth’s rotation decreased slightly, it was followed by periods of increase in the number of intense earthquakes.

“The rotation of the Earth changes slightly – in a millisecond per day sometimes – and that can be measured very accurately by atomic clocks.”

Bilham and Bendick discovered that there were periods of about five years when the rotation of the Earth was reduced by that amount several times over the last century and a half.

Fundamentally, these time lapses were followed by periods in which the number of intense earthquakes increased.

“It’s simple,” says Bilham. “The Earth is offering us a five-year warning about future earthquakes.”

This link is particularly important because the rotation of the Earth began one of its periodic decreases more than four years ago.

“The inference is clear,” concludes the researcher.

“Next year we should see a significant increase in the number of severe earthquakes. We have had it easy this year. So far, we have only had about six severe earthquakes. We could easily have 20 per year starting in 2018.”

It is not clear exactly why the decreases in the length of the day should be related to earthquakes, although scientists suspect that small changes in the behavior of the Earth’s core could be causing both effects.

Regrettably, it is difficult to predict where these additional earthquakes will occur, although Bilham said they discovered that most of the intense earthquakes responding to changes in day length seemed to occur near the equator.

Around one billion people live in the tropical regions of the Earth.

Featured image credit: Shutterstock

{ https://www.ancient-code.com/ }

21-11-2017 om 16:01 geschreven door peter  

New study published in ‘the Journal Astrobiology’ says life on Earth may have come from ‘elsewhere’

The building blocks of life on Earth may be launching into space, perhaps seeding other worlds, according to a new study published in the journal Astrobiology and available in pre-print on arXiv.

Scientists from the University of Edinburgh (United Kingdom) have published a study in the journal Astrobiology in which they have proposed a hypothesis according to which life on planet Earth could have come from other planets in the cosmos.

According to calculations, the great flow of space dust that falls on the planet, in an amount of 105 kilograms per day and at speeds of 10 to 70 kilometers per second, is enough to boost, in the upper layers of the atmosphere, small living beings towards space.

This implies that life could be transferred from Earth to other places and that the same thing could happen, or have happened, in the opposite direction.

It is observed that hypervelocity space dust, which is continuously bombarding the Earth, creates immense momentum flows in the atmosphere. Some of this fast space dust inevitably will interact with the atmospheric system, transferring energy and moving particles around, with various possible consequences

“The hypervelocity space dust forms an immense and sustained flow in the atmosphere,” wrote the authors of the study, led by Arjun Berera. “For particles that form the thermosphere or above or reach there from the ground, if they collide with this space dust, they can be displaced, altered in form or carried off by incoming space dust.”

Berera believes that our planet’s organic material could have traveled as much as 30,000 light-years over the past few billion years, which is enough time to reach most parts of the galaxy.

Tardigrades may survive the journey through space.

According to Berera, this can have many consequences for the weather and the wind.

But, what is more interesting, in the opinion of the researcher at the University of Edinburgh, “is the possibility that this type of collision can give the particles of the atmosphere the escape velocity needed to escape from Earth’s gravity.”

In this way, the flow of small particles from space, whose masses range from one gram to one trillionth of a gram, would be like a space shuttle for living beings.

This means that resistant and extremely small organisms, such as bacteria, viruses, or tardigrades, could cross the space between solar systems or even beyond, thanks to the thrust of space dust, and perhaps survive their journey.

What if life on Earth was ‘seeded’ from elsewhere?

Image credit: Shutterstock

It also means that the impact of asteroids and comets would not be the only mechanism capable of transferring life between planets, as Svante August Arrhenius theory of panspermia indicates.

Experts note how “Hypervelocity space dust is a unique entity in planetary systems like our Solar System, which is able to go past and enter the atmosphere of planets, collect samples of those planets and deposit samples of other planets. The entire system of fast space dust in a planetary system thus contains the atoms, molecules and possibly even microbial life, from all the planets and provides a means to mix them up amongst the different planets.”

“The proposal that space dust collisions could propel organisms at enormous distances between planets opens some interesting perspectives on how life and the atmospheres of planets originated,” Berera said in a statement.

“The currents of space dust present in planetary systems could be a common factor in the proliferation of life.”

The next decades of space exploration through powerful telescopes will perhaps clarify numerous questions and whether or not, hypervelocity space dust may have acted as a transport system for microbial life spreading across space.

Source:  Space dust collisions as a planetary escape mechanism

{

21-11-2017 om 15:52 geschreven door peter  

By: Nidhi Goyal 

Image by NASA Goddard on Youtube

{ http://www.industrytap.com/ }

21-11-2017 om 15:41 geschreven door peter  

Supercomputers and advanced physics made the stunning new simulation possible

BY 

CAROLYN GRAMLING 

 

BLOWIN’ IN THE WIND  Hurricane Ophelia (its core appears here as a white dot at the lower right) dragged in dust from the Sahara and smoke from wildfires in Portugal as the storm spun northeast toward Ireland in October 2017.

NASA GODDARD SPACE FLIGHT CENTER

How do you observe the invisible currents of the atmosphere? By studying the swirling, billowing loads of sand, sea salt and smoke that winds carry. A new simulation created by scientists at NASA’s Goddard Space Flight Center in Greenbelt, Md., reveals just how far around the globe such aerosol particles can fly on the wind.

The complex new simulation , powered by supercomputers, uses advanced physics and a state-of-the-art climate algorithm known as FV3 to represent in high resolution the physical interactions of aerosols with storms or other weather patterns on a global scale (SN Online: 9/21/17). Using data collected from NASA’s Earth-observing satellites, the simulation tracked how air currents swept aerosols around the planet from August 1, 2017, through November 1, 2017.

In the animation, sea salt (in blue) snagged by winds sweeping across the ocean’s surface becomes entrained in hurricanes Harvey, Irma, Jose and Maria, revealing their deadly paths. Wisps of smoke (in gray) from fires in the U.S. Pacific Northwest drift toward the eastern United States, while Saharan dust (in brown) billows westward across the Atlantic Ocean to the Gulf of Mexico. And the visualization shows how Hurricane Ophelia formed off the coast of Africa, pulling in both Saharan dust and smoke from Portugal’s wildfires and transporting the particles to Ireland and the United Kingdom. 

CURRENTS GALORE Smoke, sand and sea salt interact with hurricanes and other weather patterns from August to November 2017 in this supercomputer-powered visualization of atmospheric currents.

Citations

M.R. Radcliff et al. 2017 hurricanes and aerosols simulation. NASA. Posted online November 13, 2017.

Further Reading

C. Gramling. Intense storms provide the first test of powerful new hurricane forecast tools. Science News Online, September 21, 2017.

T. Sumner. Central American fires may intensify U.S. tornadoes. Science News Online, January 28, 2015.

J. Raloff. Salt clouds relieve some Arctic warming. Science News Online, April 22, 2011.

{ https://www.sciencenews.org/  }

21-11-2017 om 14:44 geschreven door peter  

It’s the 1st known interstellar asteroid

By Deborah Byrd in SPACE 

It swept nearest the sun in September, then sped away again, back to interstellar space. Astronomers named it `Oumuamua. It’s dark red, very elongated and unlike anything in our solar system.

A few weeks ago, we reported on a small object visiting from beyond our solar system. Now astronomers have scrutinized data from this object, which has been given the name `Oumuamua, and which must have traveled through space for millions of years before its chance encounter with our star system. The conclusion is that it’s a dark, reddish, highly-elongated rocky or high-metal-content object. And, indeed, it is the first known asteroid from interstellar space. These new results were published today (November 20, 2017) in the peer-reviewed journal Nature.

Some astronomers thought the object was a comet when the Pan-STARRS 1 telescope in Hawai`i first picked it up on October 19, as a faint point of light moving across the sky. Others thought it looked like a typical fast-moving small asteroid. As they tracked its motion through space, astronomers began to be able to calculate its orbit, showing beyond any doubt that this body did not originate from inside our solar system, like all other asteroids or comets ever observed.

Instead, this object was doubtless from interstellar space.

Observations revealed no signs of cometary activity after it passed closest to the sun in September 2017. It has now been reclassified as an interstellar asteroid – the first ever observed – and named 1I/2017 U1 (`Oumuamua).

A statement from the Institute for Astronomy (IfA) at the University of Hawaii described the intricacies of naming this object:

Originally denoted A/2017 U1 (with the A for asteroid), the body is now the first to receive an I (for interstellar) designation from the International Astronomical Union, which created the new category after the discovery. In addition, it has been officially given the name `Oumuamua. The name, which was chosen in consultation with Hawaiian language experts Ka`iu Kimura and Larry Kimura, reflects the way this object is like a scout or messenger sent from the distant past to reach out to us (`ou means “reach out for”, and mua, with the second mua placing emphasis, means “first, in advance of”).

The object’s full official name is 1I/2017 U1 (`Oumuamua), and can also be correctly referred to as 1I, 1I/2017 U1, and 1I/`Oumuamua.

View larger. | This animation shows the path of `Oumuamua, as it passed through our inner solar system in September and October 2017.

Image via NASA/JPL-Caltech.

But all of that – name, designations, characterizations of the object – came later. First, astronomers had to observe it and try to understand just what this speedy visitor to our solar system might be. And they had to do it quickly. By the time earthly telescopes first noticed it, `Oumuamua had already passed its closest point to the sun, and was heading back into interstellar space. An international team lead by astronomer Karen Meech of IfA observed the object. They gathered data from telescopes around the world, including the Canada-France-Hawaii Telescope (CFHT), the United Kingdom Infrared Telescope (UKIRT) and the Keck Telescope on Maunakea, the Gemini South telescope, and the European Southern Observatory (ESO) Very Large Telescope (VLT) in Chile. These observations led to detailed measurements of the visitor’s properties. Meech commented:

This thing is very strange.

What we found was a rapidly rotating object, at least the size of a football field, that changed in brightness quite dramatically. This change in brightness hints that `Oumuamua could be more than 10 times longer than it is wide – something which has never been seen in our own solar system.

`Oumuamua does have some similarities to small objects in the outer solar system, especially the distant worlds of the Kuiper Belt – a region of rocky, frigid worlds far beyond Neptune. While study of `Oumuamua’s colors shows that this body shares characteristics with both Kuiper Belt objects and organic-rich comets and trojan asteroids, its hyperbolic orbit says it comes from far beyond.

Meech also said the object has:

… a dark red color, similar to objects in the outer solar system, and [we] confirmed that it is completely inert, without the faintest hint of dust around it.

The astronomers said these properties suggest that `Oumuamua is dense, possibly rocky or with high metal content, lacks significant amounts of water or ice, and that its surface is now dark and reddened due to the effects of irradiation from cosmic rays over millions of years.

It is estimated to be at least 400 meters long.

Many comment on stories like this one that they don’t want to see artist’s concepts; they want to see the real thing. Here you go. This deep combined image shows the interstellar asteroid `Oumuamua at the center of the picture. It is surrounded by the trails of faint stars that are smeared as the telescopes tracked the moving asteroid. This image was created by combining multiple images from ESO’s Very Large Telescope as well as the Gemini South Telescope. The object is marked with a blue circle and appears to be a point source, with no surrounding dust.

Image via ESO/ K. Meech et al

At first – by looking backwards along the orbit that had been calculated for `Oumuamua – astronomers might have said the object had come from the approximate direction of the bright star Vega, in the northern constellation Lyra the Harp.

Things aren’t that simple, though, in our Milky Way galaxy, where everything is always moving. Although it’s travelilng about 60,000 miles/hour (95,000 km/hour), `Oumuamua has taken so long to journey to our solar system that Vega was not near that position when the asteroid was there (about 300,000 years ago). According to astronomers:

`Oumuamua may well have been wandering through the Milky Way, unattached to any star system, for hundreds of millions of years before its chance encounter with the solar system.

In fact, astronomers were expecting to find an object like this one. They estimate that an interstellar asteroid similar to `Oumuamua passes through the inner solar system about once per year. We haven’t seen them before because they are so faint and hard to spot. But recent survey telescopes, such as Pan-STARRS, are powerful enough to discover them.

That’s why team member Olivier Hainaut of European Southern Observatory commented:

We are continuing to observe this unique object, and we hope to more accurately pin down where it came from and where it is going next on its tour of the galaxy. And now that we have found the first interstellar rock, we are getting ready for the next ones!

This artist’s impression shows the 1st interstellar asteroid, which has been named `Oumuamua. Data analysis reveals that is is a dark red highly-elongated metallic or rocky object, about 400 meters long, unlike anything normally found in our solar system.

Image via ESO/ M. Kornmesser.

Bottom line: Astronomers report on the first known interstellar asteroid, which swept nearest our sun in September, then sped away again. Astronomers have named this object `Oumuamua and say it is dark red and very elongated.

Via ESO and IfA.

Source: A brief visit from a red and extremely elongated interstellar asteroid

{ http://earthsky.org/ }

21-11-2017 om 14:33 geschreven door peter  

BLACK PROJECT? Bizarre 'TR-3B triangle UFO' seen tailed by 'three military helicopters'

A STRANGE-LOOKING triangle UFO was followed by US military helicopters, it has astonishingly been claimed.

21-11-2017 om 14:21 geschreven door peter  

WAS HET WEL EEN METEOOR DIE ITALIAANSE ASTRONAUT FILMDE ( VIDEO )

Een astronaut in het ruimtestation ISS is erin geslaagd om een meteoriet die richting aarde gaat vast te leggen op beeld. 

Was het echter wel een meteoor wat de Italiaanse astronaut Paolo Nespoli zag of was het iets heel anders? 

Iets dat zelden of nooit gebeurd, is dat nu wel. Een Italiaanse astronaut in het ISS ruimtevaartstation is erin geslaagd een meteoor die onderweg is naar de aarde vast te leggen op beeld.

Het voorval gebeurde op 5 november jongstleden en de autoriteiten waren heel snel met het vrijgeven van de zogenaamde timelapse opname waarop te zien is hoe een meteoor door de lucht schiet richting aarde.

Hier volgen de beelden:

 
Was het echter wel een meteoor of misschien iets heel anders.

Tyler van Secureteam heeft de tijd genomen om de beelden uitgebreid te bestuderen en hij komt tot de conclusie dat er hier wel eens sprake kan zijn van heel iets anders.

Wat hij vreemd vindt, is dat ruimteorganisatie ESA zo snel is met het vrijgeven van beelden in de trant van: als wij als eerste dit verhaal brengen en vertellen wat het is, zal niemand verdere vragen stellen.

De enige andere keer dat men erin slaagde een opname te maken van een meteoor vanuit het ISS was in 2011 en toen zag het beeld er zo uit:

Wanneer je beiden naast elkaar zet dan ziet de recente opname er heel anders uit en lijkt het in de verste verte niet op die uit 2011.

Wanneer je het recente object verder uitvergroot, ziet het er zo uit.

Er wordt gezegd dat deze meteoor met een snelheid gevlogen zou hebben van ongeveer 150.000 kilometer per uur, maar volgens Tyler klopt die berekening niet omdat er sprake is van een timelapse opname (aaneengesloten reeks van beelden waar telkens een kleine pauze tussen zit) en zou het object in werkelijkheid veel langzamer hebben gevlogen.

Heeft hij gelijk? Of is het toch gewoon een meteoor. Kijk en oordeel zelf. 

{ http://www.niburu.co/ }

21-11-2017 om 14:04 geschreven door peter  

Nibiru heeft ons wéér niet geraakt: “Logisch, Planeet X bestáát gewoon niet” - HLN.be

Bron: Science Alert

WETENSCHAP & PLANEET NASA-wetenschapper David Morrison heeft zo stilaan zijn buik vol van de complottheorieën over Nibiru of Planeet X. Voor de derde keer in een paar weken tijd zou die het einde van de wereld inluiden, door een apocalyptische botsing met de Aarde. Maar: de bewuste planeet bestáát gewoon niet, herhaalt Morrison voor de zoveelste keer.

De vraag is ditmaal wél naar Morrison geluisterd zal worden, nu hij nog maar eens in een podcast heeft uitgeschreeuwd dat Planeet X een verzinsel is. “U vraagt mij een logische verklaring voor een compleet onlogisch idee”, zei Morrison als reactie op de derde aankondiging van het einde van de wereld in evenveel maanden. “Er is zo geen planeet, die is er ook nooit geweest, en waarschijnlijk zal die er ook nooit zijn, maar toch blijft die telkens opnieuw opduiken”, verklaarde hij stellig.

De frustratie bij Morrison is hoorbaar. Nibiru zou ons volgens de ‘believers’ al in 2003 moeten verwoest hebben. Daarna in 2012, en vervolgens op 23 september, dan op 15 oktober en... gisteren. Terwijl we dit schrijven, is de aarde er nog.

Al in 2008 schreef Morrison: “Ik ging ervan uit dat Nibiru het soort internetgerucht was dat snel zou passeren”. Mis dus. Ook toen kreeg Morrison dagelijks bezorgde vragen van mensen - vaak kinderen - die in paniek waren. Vandaag is dat nog altijd zo. “Ik kreeg onlangs nog een telefoontje”, zei Morrison in de podcast. “De wereld zou zaterdag vergaan. De man vroeg mij: ‘Zou ik gaan werken of beter bij mijn gezin blijven?’”

Nog één keertje dan. Mocht Planeet X wél bestaan, dan zouden astronomen ze al lang gespot hebben. Een planeet als Nibiru zou de positie van alle planeten verstoren en zelfs de “maan uit de baan van de aarde ejecteren”. Bovendien kwam er tot nu toe nooit iets in huis van de voorspellingen over de komst van Nibiru.

{ https://www.hln.be/ }

21-11-2017 om 13:52 geschreven door peter  

Uniek: rotsblok van buiten ons zonnestelsel bereikt ons na reis van 300.000 jaar - HLN.be

Jules van der Leeuw 

Bron: AD.nl

WETENSCHAP Ons zonnestelsel heeft voor het eerst bezoek van buiten gekregen. Een asteroïde die afkomstig is uit de eindeloze ruimte tussen de sterren, is in de afgelopen weken opgedoken in onze omgeving.

Het rotsblok heeft de naam ‘Oumuamua’ gekregen. Dat is Hawaïaans voor ‘boodschapper van ver die als eerste aankomt’, omdat een telescoop op Hawaï hem als eerste zag.

De onderzoekers denken dat de asteroïde al honderden miljoenen jaren door de Melkweg zwerft, niet gebonden aan een ster. Waarschijnlijk heeft hij er 300.000 jaar over gedaan om de oversteek te maken van de ster Vega naar ons zonnestelsel. “Tientallen jaren hebben we gedacht dat zulke objecten er zijn en nu hebben we voor het eerst direct bewijs van hun bestaan”, aldus de Amerikaanse ruimtevaartorganisatie NASA.

Doordat de asteroïde in de buurt is, hebben Europese en Amerikaanse wetenschappers hem goed kunnen bestuderen. De uitkomsten daarvan staan maandag in het wetenschapsblad Nature. ‘Oumuamua’ is roodkleurig en heeft de vorm van een sigaar. Hij is ongeveer veertig meter breed en vierhonderd meter lang. Dat is opvallend, omdat de asteroïdes en kometen in ons zonnestelsel veel minder uitgerekt zijn.

Lees ook

We hebben net boodschap verstuurd naar mogelijk buitenaardse leven op ‘superaarde’ en over 26 jaar kunnen we al antwoord hebben

‘Rotsen en metalen’

Het rotsblok draait in iets meer dan zeven uur om zijn as. Er hangt geen stofwolk omheen, wat betekent dat hij waarschijnlijk uit rotsen en metalen bestaat en geen water of ijs heeft.

Oumuamua bevindt zich nu op ongeveer 200 miljoen kilometer van de aarde, tussen de planeten Mars en Jupiter. Hij vliegt met een snelheid van 138.000 kilometer per uur van ons weg en dat maakt het steeds moeilijker om hem te bekijken. Rond de jaarwisseling wordt hij waarschijnlijk te vaag om nog te zien. In mei 2018 vliegt hij langs Jupiter, in januari 2019 passeert hij Saturnus. Daarna zal hij ons zonnestelsel langzaam achter zich laten, op weg naar het sterrenbeeld Pegasus.

Wetenschappers sluiten niet uit dat er meer asteroïdes van buiten ons zonnestelsel langsvliegen, maar tot nu toe waren ze te klein en te vaag om te zien.

{ https://www.hln.be/ }

21-11-2017 om 13:44 geschreven door peter