Apr 2, 2016
Satellite imagery, magnetometer surveys, and a preliminary excavation of the site at Point Rosee in Southern Newfoundland last year could point to a potentially fascinating discovery.
The only other Viking site in North America was found in the 1960s at L’Anse Aux Meadows on the northern tip of Newfoundland, about 300 miles from Point Rosee.
The archaeologists’ investigation will feature in “Vikings Unearthed,” a special of PBS’s NOVA science series, co-produced with the BBC, that premieres online on April 4. The special will air on PBS April 6.
Archaeologist Sarah Parcak of the University of Alabama, Birmingham, used high-resolution satellite imagery to spot ruins as small as 11 inches buried below the surface, according to NOVA. Satellites positioned around 478 miles above the Earth enabled Parcak and her team to scan a vast section of America and Canada’s eastern seaboard.
The satellite images, two magnetometer surveys, and preliminary excavations suggest “sub-surface rectilinear features,” according to the experts, who also identified possible evidence of ironworking in the form of roasted iron ore. Radiocarbon technology has dated the site to between 800 and 1300 AD.
The project was led by Parcak and co-directed by Gregory Mumford, an associate professor at the University of Alabama at Birmingham and Frederick Schwarz, of Black Spruce Heritage Services. Douglas Bolender, an archaeologist at the University of Massachusetts, Boston, and historian Dan Snow also participated in the investigation.
Read more at Discovery News
The research, published in the journal Science Advances, represents the first large-scale study of ancient DNA from early Americans.
The findings suggest that people from Siberia were isolated for around 2400-9000 years in what is now the Bering Land Bridge region (referred to as "Beringia" and including parts of Russia and Alaska) before entering North America 16,000 years ago. They traveled down the Pacific coastline, with some reaching southern Chile 14,600 years ago.
One of the descendants of these first Native Americans was "La Doncella," The Maiden, a 13-year-old girl who died during a ritual sacrifice at Mount Llullaillaco, Argentina, 500 years ago. Her frozen body, discovered in 1999, was hailed as being one of the best-preserved mummies ever found.
Bastien Llamas, a senior research associate with the University of Adelaide's Australian Center for Ancient DNA (ACAD), told Discovery News that "it seems that her mitochondrial lineage did not survive until today, and that this pattern is not unusual."
Mitochondrial DNA represents maternal genetic lineages. It was the focus of the new study. The fact that such DNA for La Doncella has not yet been found in existing Native Americans suggests that she has no direct living relatives. The researchers also could not make a modern match with the other 91 analyzed pre-Columbian remains.
Llamas said, "The fact that none of the 92 pre-Columbian mitochondrial lineages survived to today is due to a combination of factors: 1- indigenous populations were fragmented and groups lived isolated from each other; 2- some of these isolated groups became extinct following European contact; 3- many modern genetic lineages have not been surveyed yet."
It is known that many early Native Americans succumbed to diseases brought over by Europeans for which many had evolved no immunity. Such illnesses included syphilis, smallpox, measles, mumps, and the bubonic plague.
Nevertheless, Alan Cooper, who is the director of ACAD, suspects that at least some of the ancient genetic lineages did survive to modern times and will eventually be found in current populations, once enough individuals are analyzed.
Cooper explained that "demographic results show that the Beringian population was relatively small -- probably as few as 10,000 individuals -- which is consistent with what we estimate the resources in Beringia could have sustained."
He continued, "At 16,000 years ago, the population suddenly increased massively, and then kept increasing for several thousand years after that. This population increase could not occur in Beringia because of the limited resources, however, the timing coincides with a slight retreat of coastal glaciers along the northwest Pacific coast, providing a route around the ice sheets and into North America proper."
Once in the Americas, the groups appear to have splintered off, but generally migrated following the coastline. Some, via multiple generations, remarkably traveled the entire length of North, Central and South America in just 1400 years.
Carles Lalueza-Fox, a scientist at the Spanish National Research Council, told Discovery News that the new study "not only tackles the loss of genetic diversity in the current Amerindian populations as compared to the ancient, but also narrows down the date of a population expansion that is only compatible with a coastal migration route and not with the ice-free corridor that opened thousands of years later."
He suspects that the noted loss of genetic diversity could be tied to the epidemics brought in by Europeans. For example, he said that the survivors might have "had some rare resistance genetic variants," which those who perished lacked. The disease aftermath then might have reduced or eliminated some early Native American lineages in favor of others.
Read more at Discovery News
Antiquities Minister Khaled al-Anani told a press conference that a team of radar experts worked for more than 10 hours last night to obtain 40 scans of five different levels of areas on the north and eastern walls of the 3,300-year-old tomb.
Radar scanning took place with digital antennas of 400 and 900 Mhz, which can inspect up to a distance of 13 and 5 feet respectively.
“Results are expected within a week,” al-Anani said.
He added that more scans will follow at the end of April. At that time, a vertical investigation will be carried out from the hill above King Tut’s tomb using radars able to investigate areas up to 130 feet below.
“We want to take several rigorous scientific steps. In early May we will open an international debate over the results,” al-Anani said.
Minister al-Anani appeared to cool down the expectations that rose after his predecessor Mamdouh al-Damaty revealed there was a “90 percent chance” that King Tut’s tomb concealed two chambers.
Indeed, just two weeks ago, the former antiquities minister confirmed that analysis of radar scans carried out by Japanese specialist Hirokatsu Watanabu had revealed two hidden spaces on the north and eastern walls that could contain metal or organic material.
But radar experts not affiliated with the project cautioned, noting that radars can hardly distinguish archaeological features from the natural voids typical of the Valley of the Kings.
Begun last summer, the investigation inside the boy king’s burial follows a claim by Nicholas Reeves, a British Egyptologist at the University of Arizona.
In July 2015 Reeves published a paper arguing that high-resolution images of the tomb’s walls show “distinct linear traces” pointing to the presence of two still unexplored chambers.
According to Reeves, one hidden chamber would contain the remains, and possibly the intact grave goods, of Queen Nefertiti, wife of the “heretic” monotheistic pharaoh Akhenaten, Tutankhamun’s father.
Reeves speculated that the tomb of King Tut was not ready when he died unexpectedly at 19 in 1323 B.C., after having ruled a short reign of nine to 10 years. Consequently, he was buried in a rush in what was originally the tomb of Nefertiti, who had died 10 years earlier.
Read more at Discovery News
The results explain the geography of Gale Crater (the Curiosity rover’s landing site) as well as other high-topped places on the Red Planet, and confirm that wind is currently the dominant force in Mars’ geology. (Mars has no widespread plate tectonics or liquid water today).
Martian mounds have been known for decades, ever since the NASA Viking program saw them in the 1970s. More recently, the Curiosity rover has performed detailed analysis of the mound in Gale Crater. The data shows that the mound is made of sedimentary (layered) rock. Sediments at the mound’s bottom came from water, while those at the top of the mound were laid down by wind.
It was unclear, however, how the entire mound was formed. To test the theory that perhaps wind created mounds like that found in Gale Crater, researchers created a mini-crater on Earth and put it in a wind tunnel.
The crater was 30 centimeters (12 inches) wide and four centimeters (1.6 inches) deep. After putting damp sand inside, researchers watched the wind shape the sand until it was blown away. Through the process, researchers captured pictures of the “crater” that showed similar shapes to real craters and mounds on Mars.
Results were backed up by a computer model showing the wind’s movements through the crater as it progressed through different erosion stages. Researchers also pointed out that the mounds’ structure — with water-borne sediments on the bottom, and wind-borne at the top — again shows evidence of a warmer, wetter Mars in the distant past.
Read more at Discovery News
Mar 31, 2016
According to the people.cn, it’s not clear what caused the sinkhole to open, but villagers suspect activity at a nearby quarry may have had some adverse effect on the body of water.
Ultimately, the pond drained almost completely, according to the video below, from New China TV. The farmer estimates the financial loss from the swallowed fish to be more than US $75,000.
The new, extinct species, dubbed Idmonarachne brasieri, was found in France in the 1980s, according to PhysOrg, but the fossil was partly encrusted in stone, so full examination wasn’t possible until modern 3D scans gave scientists a closer look without risking damage to the specimen.
“Our new fossil occupies a key position in the evolution of spiders,” said the study’s lead author Russell Garwood, of the University of Manchester, in a press release.
“It isn’t a true spider,” said Garwood, “but has given us new information regarding the order in which the bits of the anatomy we associate with spiders appeared as the group evolved.”
The reason it’s not a “true” spider, the researchers say, is because the ancient almost-spider lacked spinnerets, the special appendages modern spiders use to spin silk.
“Our creature probably split off the spider line after [Attercopus], but before true spiders appeared,” Garwood told the BBC.
“This fossil is the most closely related thing we have to a spider that isn’t a spider,” Garwood added – a creature about six-tenths of an inch long (1.5 millimeters), with legs and a jaw that were like those of spiders, just without the spinneret.
Garwood and his team’s work was published today in the journal Proceedings of the Royal Society B.
From Discovery News
The finding promises to yield a wealth of new knowledge about one of the ancient world’s most fascinating and mysterious civilizations.
Weighing about 500 pounds and nearly four feet tall by two feet wide, the slab was unearthed at Poggio Colla, some 22 miles miles north-east of Florence in the Mugello Valley.
The stone had been buried for more than 2,500 years in the foundations of a monumental temple at the Etruscan site. It was heavily abraded and chipped, with one side reddened possibly from burning.
According to archaeologist Gregory Warden, co-director and principal investigator of the Mugello Valley Archaeological Project, which made the discovery, the 6th-century B.C. slab has at least 70 legible letters and punctuation marks.
“Now if we could only unravel that text,” Warden, professor emeritus at Southern Methodist University, Dallas, told Discovery News.
He explained that it will probably take months of study by Rex Wallace, a noted expert on the Etruscan language at the University of Massachusetts Amherst, before the researchers can say anything definitive about the text written on the stele, as such slabs are called.
“At this point we have just finished cleaning the stele, and Professor Wallace is working from photos. He will return to Italy in June to continue to work on it,” Warden said.
Warden speculates the text may refer to a goddess that was worshiped at the site.
“The center of worship was an underground fissure that was ritually treated after the destruction of the temple,” Warden said.
He explained the ritual included placing a temple block in front of the fissure, along with a gold ring and a textile embroidered with gold.
“Underground cults of this type were often associated with female divinities,” Warden said.
Considered one of the most religious cultures of the ancient world, the Etruscans were a fun-loving and eclectic people who, among other things, taught the French how to make wine, the Romans how to build roads, and introduced the art of writing into Europe.
They began to flourish around 900 B.C., and dominated much of Italy for five centuries.
Known for their art, agriculture, fine metalworking and commerce, they began to decline during the fifth century B.C., as the Romans grew in power. By 300-100 B.C., they eventually became absorbed into the Roman empire.
Since their puzzling, non-Indo-European language was virtually extinguished (they left no literature to document their society), the Etruscans have long been considered one of antiquity’s great enigmas.
Much of what we know about them comes from their cemeteries. Only the short funerary inscriptions and the richly decorated tombs they left behind have provided clues to fully reconstruct their history.
“Any text, especially a longer one, is an exciting addition to our knowledge,” Ingrid Edlund-Berry, an expert in Etruscan civilization, said.
Indeed, Poggio Colla is one of the few sites offering insight of the Etruscan life in a non-funerary context. It spans most of Etruscan history, being occupied from the seventh to the second century B.C.
Centering on the acropolis, a roughly rectangular plateau, Poggio Colla may have been the location of a cult-site for an Etruscan fertility goddess, as numerous votive objects near the sanctuary suggest.
The abundance of weaving tools and a stunning deposit of gold jewelry discovered in previous excavations, already implied that the patron divinity was female. Four years ago, a unique scene of a goddess giving birth was found on a small fragment from a ceramic vessel.
Read more at Discovery News
So researchers are taking advantage of remote sensing – using images and data recorded by satellites – to infer the extent of certain habitats and of the species within them.
Now, scientists from the University of Buffalo and Yale University have shown that there is one especially effective way of calculating the whereabouts of species, including those that may be threatened or endangered: look to the clouds.
On one level, of course, it may seem obvious: tropical forests, for example, are going to be in areas of heavy rainfall and thus cloud cover. But smaller-scale differences in cloud cover can cause variations in factors such as leaf wetness, surface temperature, precipitation and sunlight from one location to the next; and the new research, published today in the journal PLoS Biology, drills down in unprecedented detail, showing how sharp delineations in cloud cover correlate to abrupt changes in the ecosystems below.
The study used 15 years of data from NASA’s Terra and Aqua satellites, which orbit and study the Earth, to build a database containing two images per day of cloud cover for nearly every square kilometer of the planet from 2000 to 2014.
“When we visualized the data, it was remarkable how clearly you could see many different biomes on Earth based on the frequency and timing of cloudy days over the past 15 years,” said lead scientist Adam Wilson, who conducted the majority of the research at Yale University and is now an assistant professor of geography in the University at Buffalo College of Arts and Sciences.
“As you cross from one ecosystem into another, those transitions show up very clearly, and the exciting thing is that these data allow you to directly observe those patterns at 1-kilometer resolution.”
This approach proved so precise, in fact, that the researchers used it to map the size and location of habitats for two species - the montane woodcreeper (a South American bird) and king protea (a South African shrub) – in far greater detail than before.
They note that one reason for the great improvement in mapping the distribution of the woodcreeper, in particular, was that to this point scientists have estimated the extent of its habitat by examining precipitation data. Not only is that a more crude method than the fine-resolution cloud cover analysis they were able to perform, but it further loses accuracy in places – such as in the Andes, where the woodcreeper lives – where weather station networks are less dense.
Read more at Discovery News
This beautiful image captured by the ESO’s powerful Atacama Large Millimeter/submillimeter Aray (ALMA) in Chile shows the disk of gas and dust surrounding the 10 million year-old star TW Hydrae, which is located nearby — only 175 light-years from Earth. We are basically looking at the star system’s orbital plane face-on — it’s about this plane that any future planets will orbit their star.
And it looks like baby planets are forming within those dark gaps; their gravity is sweeping up the dust that was left over after TW Hydrae was formed.
“Previous studies with optical and radio telescopes confirm that TW Hydrae hosts a prominent disc with features that strongly suggest planets are beginning to coalesce,” said Sean Andrews with the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass., and lead author of the study published in the Astrophysical Journal Letters.
Observations of young star systems such as TW Hydrae act as time capsules to our solar system’s past. This is how our “proto”-solar system would have likely looked to an alien observer around 4.5 billion years ago.
By measuring the distance of the dust gaps from the central star, astronomers have realized there are likely planets forming 20 and 40 AU from the star, which happens to be the approximate orbital distances of Uranus and Pluto from the sun, respectively. But there’s also a gap close to the star that looks very familiar.
“The new ALMA images show the disc in unprecedented detail, revealing a series of concentric dusty bright rings and dark gaps, including intriguing features that may indicate that a planet with an Earth-like orbit is forming there,” said Andrews.
Planetary formation models make logical sense. After a star has formed and started nuclear fusion in its core, the left-over gas and dust from the molecular cloud it was born from begins to coalesce as a dusty spinning disk around the young star. As the disk cools, material starts to clump together. Dusty clumps grow into rocky planetesimals that sweep up more dust and debris to form protoplanets. Over millions to billions of years these evolve into planets.
From an observer’s perspective, the clumping material will carve out gaps in the protoplanetary disk, forming a pattern as can be seen in this stunning ALMA observation.
To get a closer look at TW Hydrae’s innermost dust gap, ALMA’s observing power was boosted by putting it into its high-resolution, long-baseline configuration. The array is composed of 66 radio antennae, so when they are at maximum separation (thereby increasing the observatory’s baseline), they are separated by 15 kilometers (over 9 miles). This allows the system to boost its sensitivity to see extremely fine detail in the center of the star system, giving us an unprecedented look into a protoplanetary gap only 1 AU from the star — an orbit identical to Earth’s orbital distance from the sun.
This mind-blowing observation comes only weeks after The Very Large Array in New Mexico released detailed images of a clump of material forming in a protoplanetary gap carved out in the disk surrounding the 1 million year-old star HL Tauri. HL Tauri has also been studied by ALMA and its 2014 observations were hailed as “revolutionary” by astronomers as it was the first time evidence for the formation of baby planets had been directly seen.
Read more at Discovery News
Mar 30, 2016
“An ant’s antennae are their chief sensory organs, but until now we never knew that they could also be used to send out information,” said the study’s lead author, PhD student Qike Wang, in a press release.
The antennae, the scientists found, conveys information about which nest an ant comes from, telling other ants whether they are friend or foe.
To figure that out, Wang and his team studied hundreds of ants, focusing on cuticular hydrocarbons (CHCs), a wax-like substance covering the bodies of ants, bees, flies and other insects that helps them avoid becoming dehydrated and is also a key to chemical communication.
The scientists observed that when they removed CHCs from only the antennae of an ant, leaving all other CHCs on the body intact, the non-nest-mates of the altered ant were not aggressive toward it, suggesting that the CHC-less ant’s “friend or foe” information was missing.
Thus, the researchers reasoned, the CHCs on the antennae serve particularly as a kind of beacon broadcasting an ant’s colony identification.
“Like everyone else,” Wang said, “we assumed that antennae were just receptors, but nature can still surprise us.”
In a statement, the researchers cited the work of entomologist Auguste Forel more than a century ago. Forel gathered four species of ant, removed their antennae entirely, and then watched them interact. The ants, which might otherwise have been expected to quarrel, grouped together peacefully.
“Forel’s experiment told us about antennae being used to receive chemical signals, but our research suggests that they are also a source of chemical signals,” said Wang.
The study has just been published in the journal Proceedings of the Royal Society of London B.
From Discovery News
The evolution of freakishly long necks, with some stretching over 21 feet, seemed to drive the body changes, since these plant-eating dinosaurs needed to balance their bodies with their necks or else they would have tipped over.
The following video animation, created by Peter L Falkingham of Liverpool John Moores University, shows how computer modeling allowed the researchers to estimate dinosaur body mass evolution based on fossil finds. The dinosaur Giraffatitan, aka “Giant Giraffe,” is featured:
Bates and his team explained that the ancestors of these dinosaurs were small and walked on two legs. They had long tails, small chests and small forelimbs. According to the new research, published in the journal Royal Society Open Science, this body shape concentrated the dinos’ weight close to the hip joint, which would have helped them to balance while walking on their hind legs.
As time went on, the plant-eating dinosaurs gradually altered both their size and shape from this ancestral template. They became not only significantly larger and heavier, but they also gained a proportionally larger chest, forelimbs and the gigantic neck.
The new study did not address what drove the neck size increase, but earlier research suggests that the emergence of tall trees, ferns and other plants coincided with the shift. The long necks allowed the dinosaurs to feast on such foliage and additional plant materials that many other animals could not reach, providing them with a steady, reliable food source.
In fact, the dinosaurs did not evolve to handle much speedy movement. They must have moved their stocky legs toward their food sources, stretched out their necks and eaten for much of the day. Their tails could have whacked predators out of the way, and their sheer size must have intimidated many other animals.
These plant-eating dinosaurs, known as sauropods, evolved to become some of the largest ever creatures to have walked the earth. The biggest included beasts like titanosaurs, the truly massive Argentinosaurus, and Dreadnoughtus.
Co-author Philip Mannion from Imperial College London said of the new research: “These innovations in body shape might have been key to the success of titanosaurs, which were the only sauropod dinosaurs to survive until the end-Cretaceous mass extinction, 66 million years ago.”
From Discovery News
Consisting of dozens of rock-cut tombs, the New Kingdom necropolis was found at Gebel el Sisila, a site north of Aswan known for its stone quarries on both sides of the Nile. Blocks used in building almost all of ancient Egypt’s great temples were cut from there.
“So far we have documented over 40 tombs, including a small shrine on the banks of the Nile,” Lund University archaeologist Maria Nilsson, director of the Gebel el Silsila Survey Project, told Discovery News. “Many tombs are in bad condition. They have suffered from heavy erosion and extreme decay due to the rising water and its high salt contents,” Nilsson said.
Nilsson and associate director John Ward concentrated on the cleaning of a small selection of tombs. Their team worked in cooperation with the Ministry of Antiquities as well as Kom Ombo and Aswan Inspectorates under General Directors Abd el Menum and Nasr Salama respectively.
The shrine is a small rock-cut sanctuary featuring two open chambers facing the river and an inner doorway crowned with the winged solar disc. The burials, meanwhile, consist of one to two undecorated rock-cut chambers, with one or more crypts cut into the bed rock floors.
In some cases the archaeologists found remains of the original lids.
Generally accessed via a series of steps that descend into a rough-cut squared chamber, the tombs feature entrances consisting of a square aperture that incorporate a vertical slot to either door. This would have facilitated a heavy, vertically-closing type of closure.
“Due to the lack of exterior or interior decoration, the identity of the buried persons remains unknown at this time,” Nilsson said.
Since the burials are quite elaborate in their style, Nilsson and Ward speculate they are not tombs for the quarry workers, but were rather assigned to people of higher rank.
“However, the higher officials, viziers and such that were active at Silsila were buried in Thebes, so it is likely that the people entombed in the rock-cut graves belong to the level just below the officials. We are still studying this,” Nilsson said.
Indeed, fragments of painted mud-plaster — possibly remains of decorated coffins — pieces of mummy wrappings and various beads and amulets, suggest the burials were designed for individuals of considerable status.
The archaeologists also unearthed a reversible seal ring, which depicts the cartouche of Pharaoh Thuthmosis III “Men-kheper-re” and a scarab also bearing the pharaoh’s name.
Remains of New Kingdom funerary ware included storage vessels, beer jugs, and a selection of votive vessels.
Read more at Discovery News
Did our species do them in?
The new analysis dramatically pushes back the time of disappearance of the Hobbits and associated unique animals from the site.
Before now, it was thought that these little archaic humans (Homo floresiensis) died out around 12,000 years ago, but new excavations at Liang Bua cave show that the Hobbits, as well as many other animals, disappeared 38,000 years earlier -- at about the exact same time our species first arrived in the wider region.
The timing, say scientists, is suspicious.
Bert Roberts of the University of Wollongong and co-author of the study, which appeared in Nature, told Discovery News: "The earliest known evidence of modern humans on Flores is from about 11,000 years ago and after, but we do know that modern humans were on other islands in the region around this time and had reached Australia by 50,000 years ago. So it is certainly a possibility to be considered, but solid evidence is needed in order to demonstrate it."
Climate shifts and volcanoes might have also led to the sudden demise of species in and around Liang Bua, co-lead author Matt Tocheri of Lakehead University and the Smithsonian Institution's Human Origins Program added.
Another possibility is that the tiny elephant relative, pygmy Stegodon, might have been hunted to death, leading to a devastating chain reaction.
"Pygmy Stegodon is the only large-bodied herbivore known on Flores during the Late Pleistocene, and it was clearly a primary food source for these other species," Tocheri explained. "If something happened to cause the pygmy Stegodon to crash, then it more than likely would have had an adverse effect on these other species."
The confusion about when the Hobbits and associated animals died out at Flores had to do with the depth and complexity of the cave site's geological layers.
The scientists discovered that an eroded surface sloped steeply toward the cave entrance. Much younger sediments covered it during the past 20,000 years. These newer sediments were at first attributed to the Hobbit remains, but the recent and more extensive analysis disproved that idea.
The latest excavation, instead, found that the Hobbits' skeletal remains date from 100,000 to 60,000 years ago, but stone tools consisting of hammered flakes and cores that were made by the Hobbits continue until about 50,000 years ago.
The earliest evidence of humans on Flores comes from an area called the Soa Basin, lead author Thomas Sutikna of the University of Wollongong and the National Research Center for Archaeology said. One million-year-old stone tools were found at Soa Basin and could have been made by the Hobbits or their ancestors.
The Hobbit's origins are murky, but it is suspected that they either evolved from Homo erectus, or descended from another, unknown, species of human that might have left Africa 1 to 2 million years ago.
Their skeletons, first reported in 2004, reveal that they had extremely small, chimpanzee-sized brains and that adults only stood about 3.5 feet tall. They resembled fossil human species that lived in Africa and Asia 1 to 3 million years ago.
Donald Johanson, founding director of the Institute of Human Origins at Arizona State University, said, "The exact cause of the demise of the hominids and associated animals is not yet understood, but in my view, may be related to the appearance in the area of the most aggressive of all hominin species, Homo sapiens, modern humans."
Bernard Wood of George Washington University's Center for the Advanced Study of Human Paleobiology said, "What we need now are other sites that preserve Homo floresiensis to see if their demise, and the demise of the animals and birds found with them at Liang Bua, can be linked in any way with the arrival of modern humans. Watch this space!"
Read more at Discovery News
Yes, I’m talking about “Planet X.” And yes, there’s going to be hype.
Before we dive into comet impacts, extinctions and possible exciting planet discoveries, let’s look at the dramatic history of Planet X.
At the turn of the 20th Century, astronomers were trying to track down massive planets in the outer solar system using a neat trick of planetary discovery that had already been developed by studying the orbits of known planets to see if they display any strange anomalies.
In 1846, Neptune was discovered in this way after French mathematician Urbain Le Verrier and British mathematician and astronomer John Couch Adams independently calculated the precise location of the planet by looking at orbital perturbations in Uranus’ orbit. The gravitational bulk of Neptune was intermittently tugging on Uranus, producing anomalies in its motion. Naturally, when Neptune was known, astronomers tried that trick again by precisely following Neptune’s orbit. Anomalies were found and the hunt for yet another as-yet-to-be-seen massive planet was on. This was the original hunt for Planet X.
When Pluto was discovered in 1930 by US astronomer Clyde Tombaugh, it was thought the distant world was another massive planet. However, over the years, it became clear that Neptune’s orbital perturbations were down to observational error and Pluto was actually a planetary lightweight and could have no gravitational influence over Neptune’s orbit — a factor that contributed to its re-classification as a dwarf planet in 2006 by the International Astronomical Union (IAU).
Although many more small objects have been discovered in the solar system’s hinterland (a region known as the Kuiper belt), evidence for a massive world has been wanting. The hunt for a massive Planet X pretty much ended with the discovery of Pluto.
But the mysteries of the outer solar system kept beckoning scientists and conspiracy theorists alike. Some oddities in the distribution of Kuiper belt objects, for example, appeared to hint at a massive object slowly plodding in an orbit beyond Pluto. Also, by studying the paleontological record of Earth, our planet appears to have been impacted by quasi-periodic mass extinction events. Could an undiscovered planetary body be rampaging through the Kuiper belt (or even the more distant Oort cloud), destabilizing the orbits of comets, which are then sent hurtling into the inner solar system causing all kinds of havoc to life on our planet every few million years?
The deadly potential of such a hypothesis really got the doomsayer juices flowing in the run-up to the cringe-worthy theories that would culminate with the end of the Mayan “Long Count” calendar on Dec. 21, 2012. Profiteers and fame-hunting soothsayers concocted all kinds of doomsday scenarios that would happen on that day. One of them being the nonsensical notion that Planet X (or the even more farcical “Niburu”) was rampaging through the solar system to, you guessed it, wipe out all life on Earth -- either through a cometary barrage or solar firestorm. Good times.
Needless to say, 2012 came and went and we’re still here. But this year, the Planet X hypothesis has made another comeback. This time, it’s not the punchline of a bad doomsday joke, it’s based on observations of the strange motion of objects in the outer solar system.
In January, Caltech astronomer and prolific Kuiper belt object discoverer Mike Brown and colleague Konstantin Batygin announced the discovery of a group of small icy objects beyond the orbit of Pluto that appear to be traveling in the same direction and at the same orbital inclination. The likelihood of this happening by chance is slim, so Brown and Batygin believe that their motion is caused by the presence of another — currently unseen — planet in the outer solar system perhaps 10 times the mass of Earth, orbiting up to 1,000 times the sun-Earth distance.
“When we found that, my jaw sort of hit the floor,” Brown said at the time.
So there’s indirect evidence of the existence of a massive planet that may be big enough to perturb the orbits of a group of small objects in the Kuiper belt, but small and dim enough to evade detection by infrared and visible light surveys. Like the discovery of Neptune, perhaps Brown and Batygin’s calculations will guide astronomers to the precise location of the world — nicknamed “Planet Nine.” This is most certainly an exciting time for planetary discovery within our own solar system.
Now, in a paper published in the journal Monthly Notices of the Royal Astronomical Society, the specter of mass extinctions has once again arisen and has tied itself to the hype of Planet X and the new scientific hunt for Planet Nine.
According to Daniel Whitmire and John Matese, who, in 1985, co-wrote a featured article for Time magazine titled “Did Comets Kill the Dinosaurs? A Bold New Theory About Mass Extinctions,” have revisited their mass extinction theories and formed a link with the search for Planet Nine.
By their reckoning, Earth is subject to major extinction events every 27 million years caused by a barrage of comets flung at Earth by the gravitational instabilities triggered by the eccentric orbit of a major planetary body like Planet Nine. As if a planetary bombardment wasn’t enough, more dislodged comets would disintegrate close to the sun in the inner solar system, creating clouds of debris that dim the sunlight, causing a global cooling event that speeds up the demise of life on Earth.
Read more at Discovery News
Mar 29, 2016
The gas giant appears to have experienced a pretty significant impact event and the flash of the extraterrestrial meteor was caught by amateur astronomers who just happened to be videoing Jupiter and its moons.
As the biggest and most massive planet in the solar system, the gas giant king isn’t unfamiliar with being hit by errant space rocks — Jupiter’s gravitational field is an interplanetary vacuum of sorts and is often viewed as the inner solar system’s protector. (Or is Jupiter a little more evil than that? We’re not entirely sure.) Any asteroid or comet that strays too close will be ripped to shreds and pulled into Jupiter’s unforgiving thick atmosphere at high speed.
According to Bad Astronomer Phil Plait, this latest Jupiter impact was reported by two amateur astronomers located in Austria and Ireland who saw the suspect flash on Jupiter’s limb at approximately the same time. It is unknown whether the flash was caused by an asteroid or a comet.
Having just one observer see the meteor would be interesting, but that would leave some ambiguity as to whether the flash was caused by a physical impact or a glitch in the observer’s camera CCD or some optical aberration in the telescope lens. But to have two observers seeing the event at the same time in the same place of Jupiter’s atmosphere is more than just chance. With more than one observer, the likelihood is pretty high that an asteroid or comet slammed into Jupiter on March 17.
See for yourself:
Although seeing a bright flash across millions of miles of interplanetary space may give the impression that Jupiter was hit by something pretty big, as Plait mentions in his blog, the impactor wasn’t likely more than a few tens of meters wide. As Jupiter has a more powerful gravitational field than Earth, objects will hit the Jovian atmosphere around five-times faster than they hit Earth’s atmosphere. Greater velocity means more energy, so (from the kinetic energy equation E=1/2mv2) we’d expect an object hitting Jupiter to be carrying 25 times more energy than a comparable object hitting Earth’s atmosphere. This means 25 times more energy will be released on impact, producing a way bigger flash.
If you’re experiencing a little deja vu right now, you’re right, this certainly isn’t the first time amateur astronomers have witnessed Jupiter flashing.
In 2009, a significant impact was witnessed by amateur astronomer Anthony Wesley in Australia that, after some detective work, was found to be an asteroid impact. Then in 2010, Wesley was again looking in the right place at the right time to spot another large impact and confirmed by Philippines-based amateur astronomer Christopher Go.
Read more at Discovery News
The animal, an elasmotherium Siberian rhinoceros or Elasmotherium sibiricum, was previously thought to be extinct 350,000 years ago. However, new research by experts at Tomsk State University (TSU) in Russia indicates that the “unicorn” may have existed until 29,000 years ago.
This means that the "unicorn" may have roamed the Earth at the same time as humans – a human fossil found in western Siberia in 2008 was dated to 45,000 years ago.
The researchers cite a well-preserved fossilized skull fragment discovered near Kozhamzhar village, Pavlodar, Kazakhstan as evidence for the rhino’s more recent existence. The findings are detailed in the “American Journal of Applied Science.”
“Most likely, in the south of Western Siberia it was a refúgium, where this rhino had preserved the longest in comparison with the rest of its range,” explained Andrey Shpanski, a paleontologist at TSU, in a press release. “There is another option that it could migrate and dwell for a while on the more southern areas.”
Radiocarbon dating was performed on the skull at Queen’s University, Belfast, in the U.K. “Most likely, it was a very large male of very large individual age (teeth not preserved),” said Shpanski, in the press release.
It is thought that the giant animals were about 6.7 feet tall and 15 feet long.
The rhinos could be found across a vast habitat that spanned from the Don river to the east of modern Kazakhstan, according to experts. Residue from the animal in Kazakhstan reveals that the rhinos had “quite a long existence” in the southeast of the west Siberian plain, TSU says.
From Discovery News
In a new study of 18th-century Hungarian mummies, scientists found that the genetic predisposition to colon cancer predates modern impacts on health. One of the mummies in the study carried a mutation in the adenomatous polyposis coli (APC) gene, which physicians now know raises the risk of colon cancer, said lead study author Michal Feldman, a research assistant formerly at Tel Aviv University in Israel.
If the APC mutation is confirmed in other samples, it could mean that inherited changes in DNA play a bigger role in cancer evolution than do modern environmental impacts, Feldman told Live Science in an email.
“Today, colorectal cancer is the third most common type of cancer, and it has a clear genetic background that is well-researched in modern populations,” Feldman said. “In light of the many lifestyle and environmental changes human society has undergone during the last few centuries, we found it important to compare the spectrum of historical mutations to the modern spectrum.”
Because mummification preserves tissue, samples from such remains can give scientists invaluable information on anthropological, historical and medical details, Feldman said. In the past, studies of mummified remains have provided clues about the history of tuberculosis, clogged arteries and even air pollution.
In the new study, Feldman’s team collected tissue samples from 20 mummies that were excavated from sealed crypts in a Dominican church in Vác, Hungary. These crypts were used for the burial of several middle-class families and clerics from 1731 to 1838, and more than 265 mummies were found there in 1995, the researchers said. The mummies are now housed at the Hungarian National Museum in Budapest.
The low temperature in the crypts, combined with constant ventilation and low humidity, were ideal conditions for natural mummification of the corpses, the researchers said. Some 70 percent of the bodies found in the location were completely or partially mummified, providing a rich source of preserved tissue and DNA samples for the scientists.
Read more at Discovery News
This is William Shakespeare’s epitaph, dating back to 1616. Though the world’s best- known dramatist, Shakespeare was not being dramatic when he wrote these words. Instead, he was trying to prevent something unsavory that neither his fame nor fortune could deter: his corpse being dug up by grave robbers.
His curse may not have worked, at least not centuries ago: According to a documentary that aired over the weekend, “A radar scan of William Shakespeare’s tomb has discovered signs of tampering with his final resting place that lend credence to a story about his skull being stolen in the 18th century, researchers say.”
The archaeologists cleverly avoided Shakespeare’s curse, which specifically warns against “digging dust” and “moving bones” but says nothing about using ground-penetrating radar. The findings, though indirect, give new life to speculation—long dismissed as rumor—that his head may have been stolen in 1794.
But why would anyone want to steal Shakespeare’s head?
As “The New York Times” noted, one motivation for stealing his skull can be found in phrenology, a wildly popular—and widely believed—pseudoscientific field of “study” begun in the late 1700s in which a person’s skull was believed to reveal his or her personality and other characteristics.
A prominent bump on the forehead, for example, might be assumed to reflect a proficiency in language or dramatics. It’s not surprising that the skull of one of the most famous and important literary figures in history would be coveted and examined.
Skull-Duggery and Grave Robbing
Aside from phrenological curiosity about Shakespeare’s skull specifically, there were other reasons why the bard’s bones might have been disturbed. Throughout most of history, medical knowledge of anatomy was poor and indirect, partly because of fear and taboos against cutting open corpses.
The Renaissance brought an emphasis on practical, real-world knowledge about anatomy, which necessarily meant examining and cutting up the dead. In Europe, the rise of early medical centers created a strong demand for dead bodies; a few cadavers were made available by royal decree, usually the bodies of condemned criminals. In the 1700s, in fact, dissection was a punishment for serious crimes. Demand soon outstripped supply, however, and a black market for cadavers emerged.
Centuries ago it was not uncommon to wear dead strangers’ body parts; in the 1600s and 1700s teeth and hair from dead bodies was sometimes used to make dentures and wigs, respectively (if not respectfully).
By 1720, theft from graveyards was common in London, and grave robbers (or “resurrection men,” as they were known) were making a profit digging up bodies and selling them to anatomists and doctors. Some were so eager to cash in that they didn’t wait for people to die: Irish grave robbers Brendan Burke and William Hare, for example, committed 16 murders and sold the bodies to a well-known London anatomist in 1828.
Read more at Discovery News
Even on its warmest days, Pluto is far too cold for surface lakes made of water, but they could contain liquid nitrogen during periods of time when the planet's atmosphere bulks up.
Pluto, which takes 248 years to circle the sun, turns out to have large swaths of real estate with direct overhead sunlight due to an extreme axial tilt of 120 degrees, relative to its orbital plane. Earth, by comparison, is tilted 23 degrees.
That gives Pluto a much broader range of tropical latitudes than Earth, noted New Horizons scientist Richard Binzel, with Massachusetts Institute of Technology.
Because arctic and tropical zones alternatively extend over such wide swaths of the dwarf planet's surface, Pluto has regions where both extremes occur, though not at the same time.
Pluto also has a wobble, which causes its axis to tilt up an additional 20 degrees from its present orientation, triggering long-term climate cycles that far exceed anything experienced on Earth, Binzel said.
Pluto is now in an intermediate phase between its climate extremes, with the last peak occurring less than 1 million years ago. Temperatures today measure about minus-400 degrees Fahrenheit.
Variations in the amount of sunlight falling on Pluto have direct impacts on Pluto’s atmosphere, noted New Horizon’s lead scientist Alan Stern, with the Southwest Research Institute.
“We find that Pluto’s atmospheric pressure today is atypically low and that in the past it could have been 1,000 to 10,000 times higher,” exceeding the pressure of Mars by up to 40 times, Stern said.
Computer models show that when Pluto’s temperature and atmospheric pressure are high, conditions could be suitable for liquid nitrogen.
Read more at Discovery News
Mar 28, 2016
The atlas, now published in the Journal of Vertebrate Paleontology, is the first document to display the dodo skeleton with proportional accuracy, say its creators, a team of international scientists. The atlas also describes previously unknown dodo bones such as kneecaps, ankles, and wrists.
“Being able to examine the skeleton of a single, individual dodo, truly allows us to grasp what an actual dodo looked like and how it must have operated in its island environment,” said project co-contributor Leon Claessens, of the College of the Holy Cross’s biology department, in a statement.
The “island” in question was Mauritius, in the Indian Ocean, off the east coast of Madagascar. The huge – about 3 feet tall and weighing up to 40-plus pounds — flightless bird was well adapted to life there. At least it was until Dutch colonists arrived on the island and the bird went extinct by 1693, within about 100 years of man’s arrival.
(The likely culprit for the dodo’s demise, though, was not human hunting but rather the animals that came with the colonists. Dogs, cats, and rats likely wreaked havoc with dodo eggs and young dodos.)
There are only two near-complete dodo skeletons in existence, each discovered between 1899 and 1910 by amateur naturalist Etienne Thirioux. One represents the only known complete skeleton from a single individual dodo. The other is considered near-complete and may contain bones from more than one dodo.
All other dodo samples, the atlas creators say, are not complete and use the bones of many different individual birds.
Read more at Discovery News
The finding confirms that non-stick frying pans, an essential tool in any modern kitchen, were used in the Roman Empire.
The cookware was known as “Cumanae testae” or “Cumanae patellae,” (pans from the city of Cumae) and was mentioned in the first-century Roman cookbook De Re Coquinaria as the most suitable pans for making chicken stews.
However, the pans from Cumae remained a mystery until 1975, when Giuseppe Pucci, archaeologist and professor of history of Greek and Roman art, attempted an identification.
Pucci proposed that a pottery commonly known as Pompeian Red Ware which featured a heavy red-slip coating in the inside, was the “Cumanae testae” from historical sources.
Now Marco Giglio, Giovanni Borriello and Stefano Iavarone, archaeologists at the University of Naples “L’Orientale,” have found evidence in Cumae to support Pucci’s identification.
“We found a dump site filled with internal red-slip cookware fragments. The dumping was used by a pottery factory. This shows for the first time the Cumanae patellae were indeed produced in this city,” Giglio told Discovery News.
Giglio and colleagues found more than 50,000 fragments of lids, pots and pans of various sizes and thickness, each featuring a very distinct coating.
“All the defective artifacts were dumped here. These pieces help us enormously to reconstruct the way the pottery was manufactured,” Giglio said.
Many of the fragments featured the thick internal red-slip coating that provided a non-adherent surface, making the pots and pans ideal for cooking meat-based stews.
“Apart from the production’s defects that made them end up in the dump, all the recovered fragments are of very high quality,” Giglio said.
Only 10 percent of the site once occupied by the pottery factories has been excavated at Cumae, an ancient city overlooking the Tyrrhenian Sea about 12 miles west of Naples.
One of the first Greek colonies in Italy, Cumae is best known for having been home to sibyls (Greek prophetess) whose cave was rediscovered in 1932. Rome conquered the city in 338 BC; it was then destroyed by the Neapolitans and subsequently abandoned in 1205.
Read more at Discovery News
Measuring those blue bags is crucial for Rapp, a scientist at Harvard Forest in Petersham, Mass., who is studying the impact climate change is having on syrup availability and quality. Sugar maples generally have to be about 40 years old before they're ready to be tapped, which means the knowledge scientists are building now incredibly valuable for the future of the industry.
“We’ve been having huge flows early this season,” Rapp said, standing next to a maple syrup boiler as a sweet steam rose from the bubbling vat of syrup through the vent in the roof of the sugar shack.
In what has been the warmest winter on record for New England, producers tapped trees two to three weeks earlier than usual. A little to the east of his sugar shack, Rapp said it was the “first time in memory” producers tapped their trees in January, an annual ritual usual relegated to the second or third week of February.
Maple syrup production is intimately tied to the weather. Sap only flows when temperatures rise above freezing during the day and drop below it during the night. That temperature difference creates enough pressure to push sap out of the tree — one of nature’s amazing feats.
But warming driven by human-caused climate change is having an impact on these natural processes. The easiest one to spot is the shift in maple syrup season as winters have warmed by about 1°F (0.6°C) per decade across much of the Northeast since 1970.
“In general over New York and New England, the season is now beginning about seven days earlier than it did 40-50 years ago and ending 10 days earlier,” Timothy Perkins, the director of the University of Vermont’s Proctor Maple Research Center, said on a phone call.
New York and the New England states account for about three quarters all the maple syrup produced in the U.S., an industry worth $117 million in 2014. While a change in the dates of the season is notable, it’s not exactly going to bankrupt the industry.
Warming on the southern fringe, however, is a major concern. Virginia syrup producers are already tapping at the coldest time of the year and future warming could make even that time unsuitable for maple syrup production.
And even in the syrup strongholds of New England and eastern Canada, warming could have an important impact on the amount of sap produced and its quality.
That’s why each week, Rapp weighs the bags and then proceeds to prepare that week’s batch of maple syrup (for science, of course).
His maple syrup operation is part of a network of sugar shacks at research institutions as well as commercial operations from Quebec — the world’s largest producer of maple syrup — to Virginia that are part of a project looking at the range of climate impacts on maple syrup.
Selena Ahmed, a researcher at Montana State University who is spearheading the project, said maple producers have told her team that weather within the season is becoming more variable, causing more erratic sap flows and impacting quality. The vagaries of sap flow may not mean much to the average waffle enthusiast, “but what is happening to changes in quality? That’s the big research gap and consumers can relate the most to that,” Ahmed said.
Ahmed is conducting a chemical analysis of syrup from the producers in the network to see how temperature shifts affect the compounds that give maple syrup its distinct flavor. This type of analysis will serve as a baseline for monitoring future changes to the syrup on your morning pancakes. Ahmed has done a similar analysis of tea and found changes are afoot.
Read more at Discovery News
The genetic analysis behind the map’s creation strengthens earlier findings that modern humans migrating out of Africa interbred with the populations they encountered in Europe and Asia. These populations consisted of at least two types of ancient humans: Neanderthals and Denisovans.
Neanderthals have received a lot of attention over the years, and studies have concluded that all people of European and Asian heritage are related to Neanderthals. Denisovans were identified more recently, yet these mysterious, now-extinct humans that once ranged from Siberia to Southeast Asia turn out to have really made their mark in modern genomes. People of South Asian ancestry today may actually be more Denisovan than they are Neanderthal.
The new research, published in the journal Current Biology, also determined that modern human interbreeding with Denisovans happened about 100 generations after the trysts with Neanderthals.
“There are certain classes of genes that modern humans inherited from the archaic humans with whom they interbred, which may have helped the modern humans to adapt to the new environments in which they arrived,” senior author David Reich, a geneticist at Harvard Medical School and the Broad Institute, said in a press release.
“On the flip side,” he added, “there was negative selection to systematically remove ancestry that may have been problematic from modern humans. We can document this removal over the 40,000 years since these admixtures occurred.”
Studying what ancestry was removed via natural selection, as well as what was added, is helping researchers determine which traits were favored for modern human survival as people migrated into Asia and Europe from Africa.
For example, Reich and his team said Denisovan genes could potentially be linked to a more subtle sense of smell in Papua New Guineans and high-altitude adaptions in Tibetans. Meanwhile, Neanderthal genes found in people around the world most likely contribute to tougher skin and hair.
The scientists’ analysis of Denisovan, Neanderthal and modern human genomes found that ancient human ancestry was lost from the X chromosome, as well as in genes expressed in the male testes. They believe that this has contributed to a reduction of fertility in certain men.
Read more at Discovery News
The information came from observations from the Hubble Space Telescope — which serendipitously observed 274 dwarfs while looking at distant galaxies — and the application of a density model to estimate how many there are in the galaxy. With these data, astronomers estimate there to be 58 billion red dwarfs, which will keep mappers busy for many years.
“Astronomers believe that there are very many of these stars. That makes them really quite suitable for mapping the galaxy even though they are so hard to find,” said Leiden Astronomy student Isabel van Vledder, one of the researchers on the paper, in a statement. Co-leading the paper was Dieuwertje van der Vlugt, also a student.
The students looked at M-class red dwarf stars, which are also locations where planet-hunters often seek out planets. The stars are too small to burn hydrogen and are dimmer than our own sun, making it easier to detect faint planets.
The research also has implications for future mapping missions, particularly the upcoming Euclid Space Telescope that the European Space Agency expects to launch in 2020. Euclid will map the whole sky in infrared light, where dwarfs are easiest to spot.
“With our research, astronomers can now better assess whether they are dealing with a distant galaxy or a star in our own galaxy,” Van Vledder said.
The students used three density models to determine the disk and the halo of the Milky Way (both together and separately). Using the Monte Carlo statistical modelling method, the students then determined which density model was best. It turned out to be the one that included both the disk and the halo of our galaxy.
Read more at Discovery News
Mar 27, 2016
Crucifixion was a Roman method of punishment. Suspended from a large cross, a victim would eventually die from asphyxiation or exhaustion – it was long, drawn-out, and painful. It was used to publicly humiliate slaves and criminals (not always to kill them), and as an execution method was usually reserved for individuals of very low status or those whose crime was against the state. This is the reason given in the Gospels for Jesus’s crucifixion: as King of the Jews, Jesus challenged Roman imperial supremacy (Matt 27:37; Mark 15:26; Luke 23:38; John 19:19–22).
Crucifixion could be carried out in a number of ways. In Christian tradition, nailing the limbs to the wood of the cross is assumed, with debate centering on whether nails would pierce hands or the more structurally sound wrists. But Romans did not always nail crucifixion victims to their crosses, and instead sometimes tied them in place with rope. In fact, the only archaeological evidence for the practice of nailing crucifixion victims is an ankle bone from the tomb of Jehohanan, a man executed in the first century CE.
So was Jesus nailed to the cross?
Some early Gospels, such as the Gospel of Thomas, don’t include the narrative of Jesus’s crucifixion, choosing instead to focus on his teaching. But Jesus’s death by crucifixion is one of the things that all four canonical Gospels agree on. Matthew, Mark, Luke, and John, all include the crucifixion event in their own slightly different ways.
None of the Gospels in the New Testament mentions whether Jesus was nailed or tied to the cross. However, the Gospel of John reports wounds in the risen Jesus’s hands. It is this passage, perhaps, that has led to the overwhelming tradition that Jesus’s hands and feet were nailed to the cross, rather than tied to it.
Over the past few years, several people have claimed to have found the actual nails with which Jesus was crucified. Each time, biblical scholars and archaeologists have rightly pointed out the assumptions and misinterpretations of evidence behind these claims. Curiously, this fixation on the nails persists, despite the fact that the earliest gospels make no mention of Jesus being nailed to the cross.
Depictions Of The Crucifixion
It isn’t surprising that Christians took a while to embrace the image of Christ on the cross, given that crucifixion was a humiliating way to die. What is surprising is what the earliest image of the crucifixion turns out to be. Rather than the devotional icons with which we are familiar – pictures that glorify Jesus’s death – this earliest image appears to be some late second-century graffiti mocking Christians.
|Called the Alexamenos Graffito, artist Rodolfo Lanciani shows a figure with the head of a donkey on a cross with the words: “Alexamenos worships his God.”|
Gemstones, some used for magical purposes, also provide some of our earliest depictions of the crucified Jesus. This second or third century piece of carved jasper depicts a man on a cross surrounded by magic words.
|This second or third century piece of carved jasper depicts a man on a cross surrounded by magic words.|
|Constanza gemstone with the crucified Christ, surrounded by 12 apostles.|
Since the evidence from antiquity doesn’t provide a clear answer as to whether Jesus was nailed or tied to his cross, it’s tradition that dictates this common depiction. Those who have seen the film The Passion of the Christ will recall how much time the director, Mel Gibson, devoted just to the act of nailing Jesus onto the cross —- almost five whole minutes.
Read more at Discovery News
In all, there were 12 such eruptions centered on the region of the Snake River Valley, and while that is roughly half as many as had been previously believed, they were “significantly larger” than had been calculated.
“While it is well-known that Yellowstone has erupted catastrophically in recent times, perhaps less widely appreciated is that these were just the latest in a protracted history of numerous catastrophic super-eruptions that have burned a track along the Snake River eastwards from Oregon to Yellowstone from 16 million years ago to the present,” said Tom Knott of the University of Leicester Department of Geology’s Volcanology Group.
Knott was the lead author of the new study, which was just published in the journal Geological Society of America Bulletin.
“The size and magnitude of this newly defined eruption is as large, if not larger, than better known eruptions at Yellowstone, and it is just the first in an emerging record of newly discovered super-eruptions during a period of intense magmatic activity between 8 and 12 million years ago,” he added.
To reach their conclusions, the researchers painstakingly pieced together numerous pieces of evidence, including examining widespread glassy deposits fused to the landscape, each of which preserves subtly distinctive magnetic, mineralogical, and chemical characteristics that allow them to be traced great distances. They also drilled deep into rock composed of ancient volcanic ash.
They found that one of the super-eruptions from the Yellowstone hotspot-track, defined as the Castleford Crossing eruption, occurred about 8.1 million years ago; they estimated the eruption volume exceeded 1,900 cubic kilometers (456 cubic miles). To put that into some kind of perspective, that would be more than enough to completely fill Lake Ontario.
The strength of that eruption was calculated to be approximately 8.6 on the Volcanic Explosivity Index (VEI). That means it was hundreds of times more powerful than the Mt. Pinatubo eruption in the Philippines in 1991, which had a VEI of 6 and was itself 10 times more powerful than the 1980 Mt. St. Helens event.
The hotspot track gradually worked its way eastward to Yellowstone, where an eruption 640,000 years ago formed the Yellowstone Caldera. The most recent eruption at Yellowstone was 170,000 years ago, and the last lava flow was about 70,000 years ago.
Read more at Discovery News
|A grand canyon called Ithaca Chasma cuts across the fact of Saturn’s moon Tethys in this image from NASA’s Cassini probe. Scientists think the canyon opened millions of years ago when Tethys was orbitally synced with sister moon Dione.|
The idea that some of Saturn’s moons may be relatively modern stems from computer models that simulated the moons’ gravitational interactions and shifting orbital tilts over time.
SETI Institute astronomer Matija Cuk and colleagues conclude that the moons inferior to giant Titan are not primordial, and most likely formed in the last 2 percent of the planet’s 4.5 billion-year history.
Saturn hosts at least 62 moons, 53 of which are currently named. The tally doesn’t include the hundreds of small icy objects that comprise the planet’s rings.
Titan, Saturn’s largest moon (which is bigger than the planet Mercury), is the only moon in the solar system that has a thick atmosphere.
Though most of Saturn’s current moons may be relatively new, the models show the planet has always had hordes of orbital companions.
“Our best guess is that Saturn had a similar collection of moons before, but their orbits were disturbed by a special kind of orbital resonance involving Saturn’s motion around the sun. Eventually, the orbits of neighboring moons crossed and these objects collided. From this rubble, the present set of moons and rings formed,” Cuk said in a statement.
The research is published in The Astrophysical Journal.
From Discovery News