среда, 19 декабря 2018 г.

HiPOD (19 December 2018): Ancient Highlands    – Ancient bedrock…



HiPOD (19 December 2018): Ancient Highlands 


   – Ancient bedrock often has ancient tales to tell. (Alt: 254 km. Black and white is less than 5 km across; enhanced color is less than 1 km.)


NASA/JPL/University of Arizona


A new neptune-size exoplanet

The remarkable exoplanet discoveries made by the Kepler and K2 missions have enabled astronomers to begin to piece together the history of the Earth and to understand how and why it differs from its diverse exoplanetary cousins.











A new neptune-size exoplanet
An image of Neptune taken by the Voyager spacecraft compared with an artist’s conception of the exoplanet K2-263b
[Credit: NASA; exoplanetkyoto.org]

Two still outstanding puzzles include the differences between the formation and evolution of rocky versus non-rocky small planets, and why there seem to be a size gap with very few exoplanets at or about two Earth-radii in size (planets with smaller radii are likely to be rocky or Earth-like in their composition).


In order to estimate an exoplanet’s composition its density is needed, requiring a measurement of mass as well as size. While a radius can be estimated from the shape of the planet’s transit curve as it blocks out its host star’s light, a mass is more difficult to determine. In order to develop the emerging picture, however, precise and accurate masses are required for more planets that are similar in size to the Earth.


The K2 exoplanetary mission is the revived version of the Kepler exoplanetary discovery mission. Together they have discovered thousands of exoplanets, and uncovered a remarkable and unexpected diversity in the exoplanet population. K2 is sensitive only to short-period planets (it has only found a few with periods longer than 40 days).


The exoplanet K2-263b orbits a star less massive than the sun (0.86 solar-masses) and located 536 light-years away as measured with the new Gaia satellite. This exoplanet has a radius of 2.41 Earth-radii (with a 5% uncertainty). CfA astronomers Maria Lopez-Morales, Dave Charbonneau, Raphaelle Haywood, John Johnson, Dave Latham, David Phillips, and Dimitar Sasselov and their colleagues used the HARPS-N high precision spectrometer on the Telescopio Nazionale Galileo in La Palma, Spain, to measure the periodic velocity of the exoplanet as it orbited and thus to derive its mass.


The HARPS-N velocity measurements were amazingly precise – uncertain to about a mere eleven miles an hour, about the speed of a slow bicyclist. From the orbital details the scientists obtained an exoplanet mass of 14.8 Earth-masses and a hence a density of about 5.6 grams per cubic centimeter (for comparison, the density of water is one gram per cubic centimeter, and the average density of the rocky Earth is 5.51 grams per cubic centimeter).


The scientists conclude that K2-263b most likely contains an equivalent amount of ices compared to rocks, roughly consistent with current ideas about planet formation and the relative abundances in a circumstellar nebula of the building-block elements like iron, nickel, magnesium, silicon, oxygen, carbon and nitrogen.


The findings are published in Monthly Notices of the Royal Astronomical Society.


Source: Harvard-Smithsonian Center for Astrophysics [December 14, 2018]




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A young star caught forming like a planet

Astronomers have captured one of the most detailed views of a young star taken to date, and revealed an unexpected companion in orbit around it.











A young star caught forming like a planet
Artist’s impression of the disc of dust and gas surrounding the massive protostar MM 1a, with its companion
MM 1b forming in the outer regions [Credit: J. D. Ilee/University of Leeds]

While observing the young star, astronomers led by Dr John Ilee from the University of Leeds discovered it was not in fact one star, but two.


The main object, referred to as MM 1a, is a young massive star surrounded by a rotating disc of gas and dust that was the focus of the scientists’ original investigation.


A faint object, MM 1b, was detected just beyond the disc in orbit around MM 1a. The team believe this is one of the first examples of a “fragmented” disc to be detected around a massive young star.


“Stars form within large clouds of gas and dust in interstellar space,” said Dr Ilee, from the School of Physics and Astronomy at Leeds. “When these clouds collapse under gravity, they begin to rotate faster, forming a disc around them. In low mass stars like our Sun, it is in these discs that planets can form.”


“In this case, the star and disc we have observed is so massive that, rather than witnessing a planet forming in the disc, we are seeing another star being born.”


By measuring the amount of radiation emitted by the dust, and subtle shifts in the frequency of light emitted by the gas, the researchers were able to calculate the mass of MM 1a and MM 1b.











A young star caught forming like a planet
Observation of the dust emission (green) and the cool gas around MM1a (red is receding gas, blue is approaching gas),
indicating that the outflow cavity rotates in the same sense as the central accretion disc. MM1b is seen orbiting
 in the lower left [Credit: J. D. Ilee/University of Leeds]

Their work, published in the Astrophysical Journal Letters, found MM 1a weighs 40 times the mass of our Sun. The smaller orbiting star MM 1b was calculated to weigh less than half the mass of our Sun.


“Many older massive stars are found with nearby companions,” added Dr Ilee. “But binary stars are often very equal in mass, and so likely formed together as siblings. Finding a young binary system with a mass ratio of 80:1 is very unusual, and suggests an entirely different formation process for both objects.”


The favoured formation process for MM 1b occurs in the outer regions of cold, massive discs. These “gravitationally unstable” discs are unable to hold themselves up against the pull of their own gravity, collapsing into one – or more – fragments.


Dr Duncan Forgan, a co-author from the Centre for Exoplanet Science at the University of St Andrews, added: “I’ve spent most of my career simulating this process to form giant planets around stars like our Sun. To actually see it forming something as large as a star is really exciting.”


The researchers note that newly-discovered young star MM 1b could also be surrounded by its own circumstellar disc, which may have the potential to form planets of its own – but it will need to be quick.











A young star caught forming like a planet
Observation of the dust emission (green) and hot gas rotating in the disc around MM 1a (red is receding gas,
blue is approaching gas). MM 1b is seen the lower left [Credit: J. D. Ilee/University of Leeds.]

Dr Ilee added: “Stars as massive as MM 1a only live for around a million years before exploding as powerful supernovae, so while MM 1b may have the potential to form its own planetary system in the future, it won’t be around for long.”


The astronomers made this surprising discovery by using a unique new instrument situated high in the Chilean desert – the Atacama Large Millimetre/submillimetre Array (ALMA).


Using the 66 individual dishes of ALMA together in a process called interferometry, the astronomers were able to simulate the power of a single telescope nearly 4km across, allowing them to image the material surrounding the young stars for the first time.


The team have been granted additional observing time with ALMA to further characterise these exciting stellar systems in 2019. The upcoming observations will simulate a telescope that is 16km across – comparable to the area inside of the ring-road surrounding Leeds.


Source: University of Leeds [December 14, 2018]



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A nuclear-powered ‘tunnelbot’ to search for life on Jupiter’s icy moon...

Between 1995 and 2003, NASA’s Galileo spacecraft made several flybys of Jupiter’s moon, Europa. Several findings from observations of the moon pointed to evidence of a liquid ocean beneath Europa’s icy surface. The ocean, researchers believe, could harbor microbial life, or evidence of now-extinct microbial life.











A nuclear-powered 'tunnelbot' to search for life on Jupiter's icy moon Europa
Artist’s rendering of the Europa “tunnelbot”
[Credit: Alexander Pawlusik, LERCIP Internship
Program NASA Glenn Research Center]

While researchers generally agree on where to look – underneath the thick, planet-wide ice shell where water is in contact with a rocky core and where biochemical ingredients for life may exist – how to get there to collect samples remains a major tactical problem.


“Estimates of the thickness of the ice shell range between 2 and 30 kilometers (1.2 and 18.6 miles), and is a major barrier any lander will have to overcome in order to access areas we think have a chance of holding biosignatures representative of life on Europa,” said Andrew Dombard, associate professor of earth and environmental sciences at the University of Illinois at Chicago.


Dombard and his colleagues presented a possible solution to this problem at the American Geophysical Union meeting in Washington, D.C., this week: a nuclear-powered tunneling probe.


Dombard and his spouse, D’Arcy Meyer-Dombard, associate professor of earth and environmental sciences at UIC, are part of a group of scientists on the NASA Glenn Research COMPASS team, a multidisciplinary group of scientists and engineers tasked with designing technology and solutions for space exploration and science missions.


The group performed a concept study for a nuclear-powered “tunnelbot” that can penetrate the ice shell and reach the top of Europa’s ocean while carrying devices and instruments that can be used to search for signs of life or extinct life. The bot would also evaluate the habitability of the ice shelf itself.


“We didn’t worry about how our tunnelbot would make it to Europa or get deployed into the ice,” Dombard said. “We just assumed it could get there and we focused on how it would work during descent to the ocean.”


The bot would sample ice throughout the shell, as well as water at the ice-water interface, and would look at the underside of the ice to search for microbial biofilms. The bot would also have the capability of searching liquid water “lakes” within the ice shell.


The researchers considered two designs for their bot: one powered by a small nuclear reactor, and the other powered by General Purpose Heat Source bricks—radioactive heat source modules designed for space missions. Heat from both these sources could be used to melt the ice shell. Communications would be provided by a string of “repeaters” connected to the bot by fiber optic cables.


NASA routinely sponsors concept studies to test where the technology is that is needed to answer important questions in the solar system. Perhaps no question is more significant than, “Is there life elsewhere?” and Europa is one of the best places to look. Whether a tunneling mission is scheduled, and if so, whether one of these designs is selected, remains to be seen.


Kathleen Craft from the Applied Physics Laboratory at Johns Hopkins University and COMPASS team leads Steven Oleson and J. Michael Newman of the NASA Glenn Research Center also worked on the concept study.


Author: Sharon Parmet | Source: University of Illinois at Chicago [December 14, 2018]



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Scientists warn of slow progress towards United Nations biodiversity targets

Scientists from the United States and Brazil warn that the current global progress toward United Nations (UN) sustainability goals is not fast enough to avert the biodiversity crisis. A scientific team led by the California Academy of Sciences evaluated progress toward current biodiversity targets put forth by the UN Convention for Biological Diversity specifically aimed at protecting the world’s oceans and seas.











Scientists warn of slow progress towards United Nations biodiversity targets
An unprotected coral head off of Easter Island, Chile will now have a chance to be integrated into a recently
created MPA [Credit: Luiz Rocha © 2017 California Academy of Sciences]

In an essay published in Perspectives in Ecology and Conservation, they argue that most signatory countries are not on track to achieve target goals, some of the targets are structured to give a false sense of conservation achievement, and that these targets must be restructured to incorporate adequate conservation incentives that instill valid hope for the future.


“We want to call attention to the fact that while the commitments of signatory parties to UN sustainability goals are important and necessary, they’re also overlooking critical conservation challenges,” says lead author and Academy postdoctoral researcher Dr. Hudson Pinheiro. “We want policy leaders to recognize that some targets need to be reassessed and improved in order to optimize the sustainability of the world’s marine ecosystems and make real progress towards averting the biodiversity crisis.”


In their assessment, the team considered the Paris Accords, which includes 17 Sustainable Development Goals (more specifically SDG-14, which deals with ocean issues), and the Aichi Biodiversity Targets (Target 11 to protect 10% of the ocean by 2020). These goals are continually promoted by the UN Convention for Biological Diversity and signatory countries, which most recently convened in Egypt last week.


The team presented challenges and recommendations related to the following areas of conservation priority: marine protected areas, coastal ecosystem management, overfishing, marine pollution, and ocean acidification.


One sustainability target highlighted by the team requires signatory countries to protect 10% of their coastal waters as marine protected areas, or MPAs, by the year 2020. However, many countries are protecting large expanses of ocean that are low-conflict and of little biological diversity — rather than focusing on coastal regions most in need — in order to meet the target.


“Near-shore waters have a greater diversity of species and face more immediate threats from energy extraction, tourism, development, habitat degradation and overfishing,” says Dr. Luiz Rocha, Academy co-leader of the Hope for Reefs initiative, who in a New York Times op-ed last year argued that the establishment of a large, open-ocean MPA in Brazil was well-intentioned but significantly flawed. “If we leave these highly vulnerable and biodiverse places at risk, we’re not really accomplishing the goal of protecting the seas.”


To dissuade countries from protecting large swathes of ocean habitat that favor low-conflict, low-diversity areas, the team recommends dropping the numerical target of protecting 10 percent of a country’s marine territory. Instead, countries should focus on protecting the highest number of species and ecosystem types to better align with end conservation goals.


The team also evaluated sustainability targets that aim to minimize the impacts of ocean acidification on marine ecosystems by slowing greenhouse gas emissions. They note that, in order to reduce fossil fuel consumption to meet these targets, many countries have turned their focus to expanding “clean” energy sectors, like hydroelectricity, that still depend on environmentally polluting practices.


The team supports several adaptive management approaches, including encouraging industry leaders and local governments to promote policies that further marine conservation despite the position of their respective national governments. For example, the California Academy of Sciences became the first major museum to sign onto the Paris Accords last year when the federal government refused to commit, and the states of California and São Paulo are advancing at a much faster pace to reaching targets than their home countries (United States and Brazil).


“Investment in education and outreach is essential,” says Pinheiro. “Now is the time for scientists, managers, and stakeholders to work together to defend marine biodiversity, ecosystem services, and resources that the world depends on. And it starts with a critical re-evaluation of sustainability targets, how they are being met, and how they motivate marine conservation.”


Source: California Academy of Sciences [December 14, 2018]



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2018 December 19 A Rainbow Geminid Meteor Image Credit &…


2018 December 19


A Rainbow Geminid Meteor
Image Credit & Copyright: Dean Rowe


Explanation: Meteors can be colorful. While the human eye usually cannot discern many colors, cameras often can. Pictured is a Geminid captured by camera during last week’s meteor shower that was not only impressively bright, but colorful. The radiant grit cast off by asteroid 3200 Phaethon blazed a path across Earth’s atmosphere longer than 60 times the angular diameter of the Moon. Colors in meteors usually originate from ionized elements released as the meteor disintegrates, with blue-green typically originating from magnesium, calcium radiating violet, and nickel glowing green. Red, however, typically originates from energized nitrogen and oxygen in the Earth’s atmosphere. This bright meteoric fireball was gone in a flash – less than a second – but it left a wind-blown ionization trail that remained visible for several minutes, the start of which can be seen here.


∞ Source: apod.nasa.gov/apod/ap181219.html


Climate change leading to water shortage in Andes, Himalayas

Climate change could have devastating effects on vulnerable residents in the Andes mountains and the Tibetan plateau, according to researchers at The Ohio State University who have been studying glaciers in those areas for decades.











Climate change leading to water shortage in Andes, Himalayas
Quelccaya glacier [Credit: Ohio State University]

Their findings–that glaciers in both parts of the world are melting more rapidly than at any point in the last 10,000 years–mean the water supply in parts of Peru, Pakistan, China, India and Nepal will decline, soon.


“Supply is down. But demand is up because of growing populations,” said Lonnie Thompson, a climate scientist at Ohio State’s Byrd Polar and Climate Research Center. “By 2100, the best case scenario is that half of the ice will disappear. Worst-case scenario: two-thirds of it will. And you’ve got all those people depending on the glacier for water.”


Thompson, a distinguished university professor of earth sciences at Ohio State, presented the team’s findings on Dec. 14 at the annual meeting of the American Geophysical Union in Washington, D.C.


Thompson has been studying and documenting the effects of climate change on glaciers in Peru for more than 40 years. The glaciers there supply critically needed water for people, crops and livestock. In 2016, Thompson and researchers in China and India launched a research initiative to conduct similar research on the Tibetan plateau, which holds thousands of glaciers that supply water to people in parts of Afghanistan, Bhutan, China, India, Nepal, Pakistan and Tajikistan. The international research team dubbed the plateau the “Third Pole” because it contains the largest stores of freshwater in the world outside of the North and South poles.


Since then, they have drilled ice core samples from across the Tibetan plateau and the Andes mountains, examining the ice for clues about temperature, air quality and other large-scale events in history.


“The last 200 years or so, we really understand,” Thompson said. “Now we are looking at the last 10,000 years.”


What they are finding is causing him some alarm.


There have been times throughout history when the glacial ice cores showed temperatures increased–during an El Nino, for example. But within the last century, the cores from both the Andes and the Himalayas show widespread and consistent warming.


“This current warming is not typical,” Thompson said. “It is happening faster, it is more persistent and it is affecting glaciers in both Peru and India. And that is a problem, because a lot of people rely on those glaciers for their water.”


Melting glaciers can trigger such hazards as avalanches and floods. And they also can have long-lasting effects on a region’s water supply.


As the glaciers melt, initially those regions will have more water. But over time, as the glaciers shrink, the water those glaciers typically supply will dwindle, Thompson said.


“Precipitation is down and temperatures are up and that leads to retreating glaciers,” he said. “There are 202 million people in Pakistan who rely on water from the Indus River–and that river is fed by the glacier.


The effects in Peru, too, could be far-reaching, particularly on Peruvian agriculture and on the water supply in Lima, the Peruvian capital.


Thompson and his team are hoping that by studying the glaciers in both areas, they will find answers to slow glacial retreat–or to provide new water sources to at-risk areas.


“The problems are similar in both the Andes and the Tibetan plateau,” he said. “The hope is that by finding solutions, we can help both places.”


Source: Ohio State University [December 14, 2018]




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Roof-tiles with flower patterns found in Japan’s Hachiya ruins

Roof-tile pieces with flower-like ornaments that were unearthed at the Hachiya ruins in Ritto, Shiga Prefecture, are believed to have come from a temple founded in late seventh century and connected to the famed Horyuji temple in Nara Prefecture.











Roof-tiles with flower patterns found in Japan's Hachiya ruins
The pattern of a roof-tile ornament unearthed from the Hachiya ruins in Ritto, Shiga Prefecture, matches
those found at Horyuji temple [Credit: Shiga Prefectural Association for Cultural Heritage]

The ornaments, matching the Horyuji-style roof-tile pattern, were among numerous items discovered in Hachiya archaeological site in Ritto.


Two high-profile ornaments of another pattern were also found in the Hachiya ruins.


It is highly likely that the pair of Hachiya ornaments were created in a wooden mold that was also used for the tiles discovered earlier at the Wakakusa Garan ruins at the Horyuji temple compound and the Chuguji temple ruins, both in Ikaruga, Nara Prefecture.


The pattern on the Hachiya ornaments is the same as that previously installed on the roof of the Saiin Garan building in the Horyuji temple compound. The building was constructed after Horyuji temple was burned down in 670.











Roof-tiles with flower patterns found in Japan's Hachiya ruins
A roof-tile ornament discovered at Horyuji temple in Ikaruga, Nara Prefecture
[Credit: Nara National Research Institute for Cultural Properties]

The tiles in Ritto are the first found outside of the two sites in Nara Prefecture.


“The discovery (in Ritto) is physical evidence that the temple was founded under the strong influence of the Horyuji temple,” said Hiromichi Hayashi, professor emeritus of archaeology at the University of Shiga Prefecture.


Some objects believed to be pieces of ornamental ridges from the roof were also found in the Hachiya ruins, the Shiga Prefectural Association for Cultural Heritage said Nov. 1.


Ancient settlements existed at the site of the Hachiya ruins between the Jomon Pottery Culture period (c. 8000 B.C.-300 B.C.) and the Muromachi Period (1338-1573).











Roof-tiles with flower patterns found in Japan's Hachiya ruins
Numerous pieces of centuries-old roof tiles are discovered in the Hachiya ruins in Ritto,
Shiga Prefecture [Credit: Yotaro Okamoto]

Around the area, certain traditions that continue today are connected to the Hachiyaji temple. In addition, some district names, such as Munedera, are evidence that the area was once home to a temple. “Tera” or “dera” means temple in Japanese.


Traces of four ditches in a north-south direction were found during the excavation project that has been conducted by the Shiga Prefectural Association for Cultural Heritage since April. The ornaments and tile pieces were unearthed from those ditches.


In ancient times, the northern area of Ritto where the Hachiya ruins are located was the domain of the Mononobe family, an influential clan in the ruling class of the old-time government. It was called the “Mononobe Go” district.


The clan fought and lost to the powerful Soga family on whether to accept Buddhism in late sixth century.











Roof-tiles with flower patterns found in Japan's Hachiya ruins
Credit: The Asahi Shimbun

As a result, the ownership of Mononobe’s domain shifted to Shotoku Taishi (Prince Shotoku 574-622).


Horyuji temple took over the clan’s land because Shotoku Taishi fought on the side of the Soga family, and he was the one who founded the Horyuji temple.


Shotoku Taishi has been called Umayadono no Miko (Prince Umayado).


According to a document compiled by representatives of the Horyuji temple in the mid-eighth century, the region of northern Ritto is owned by the temple.


Author: Yotaro Okamoto | Source: The Asahi Shimbun [December 14, 2018]



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8,300-year-old ritual stone snake heads discovered in Ukraine

What might be passed over as two oddly shaped rocks are the work of Stone Age artisans who sculpted the rocks into beady-eyed snake heads, archaeologists have found.











8,300-year-old ritual stone snake heads discovered in Ukraine
The archaeological site known as Kamyana Mohyla I (arrow), where the stone snakes were discovered.
Nearby sits the Kamyana Mohyla stone mound [Credit: Kotova N., et al., Antiquity 2018;
aerial photograph by S. Radchenko]

It’s a mystery why these ancient people, who lived in what is now Ukraine, created the stoney serpents, but the researchers have a good guess.


“These sculptures could have ritual purpose,” said study lead researcher Nadiia Kotova, an archaeologist in the Department of the Eneolithic and Bronze Age at the Institute of Archaeology National Academy of Sciences (NAS) of Ukraine. “They were probably used during ceremonies.”


Kotova and her team found the snakey stones in 2016, during an excavation at Kamyana Mohyla I, an archaeological site near the city of Terpinnya. Both stones, although different ages, were found near ancient bones and flints from the same period: the Mesolithic, which is the middle Stone Age between the earlier Paleolithic and later Neolithic. There were many sandstones at the site, but “these two had quite a strange shape, so we decided to look closer,” Kotova told Live Science in an email.











8,300-year-old ritual stone snake heads discovered in Ukraine
The “younger” snape sculpture has triangular eyes [Credit: Kotova N., et al., Antiquity 2018;
 figure by N. Kotova]

The “older” figurine was found near an open fireplace, near piles of shells and flint tools. Using organic matter from the fireplace, the researchers were able to radiocarbon date the yellow sandstone snakehead to between 8300 BC. and 7500 BC.
This snakehead is small, measuring only 5 inches by 3 inches (13 by 6.8 centimeters) and weighing almost 3 lbs. (1,215 grams). It has a triangular shape with a flat bottom. “Two rhombic eyes were carved on the upper surface alongside two knobs” on the stone, the researchers wrote in the study. “A wide, long line represents a mouth.”


Regrettably, the snake was “damaged on the ‘nose’ during excavation,” the researchers wrote in the study.











8,300-year-old ritual stone snake heads discovered in Ukraine
The “older” figurine of the snake. Notice its rhombic eyes [Credit: Kotova N., et al., Antiquity 2018;
figure by N. Kotova]

The “younger” stone snake was also found by a fireplace and was dated to about 7400 BC. It measures about 3 inches by 2 inches (8.5 by 5.8 cm) and weighs just under 1 lb. (428 grams), meaning it can comfortably fit in a person’s hand, Kotova said.
“The smaller stone has a flattened, round shape and so-called ‘neck,'” Kotova said. “There are two deep traces, probably the eyes of the creature. There is also kind of a nose.”


The two findings represent the only snakehead stones known at Kamyana Mohyla I. However, scientists did discover a fish-like stone sculpture at the nearby Kamyana Mohyla, a giant stone pile just a stone’s throw from the snakeheads’ spot.











8,300-year-old ritual stone snake heads discovered in Ukraine
The fish-like stone that was found in the Kamyana Mohyla mound [Credit: Kotova N., et al., Antiquity 2018;
image courtesy of B. Mykhailov]

Archaeologists don’t know much about the people who made these sculptures, except that these prehistoric inhabitants lived on the steppe of the northwestern region of the Sea of Azov. “They made tools from stones, flints and bones and hunted with bows and flint arrows,” Kotova said. “It was the society of hunters and gatherers. Unfortunately, we don’t know much about their cultural traditions yet.”


The study was published online in the journal Antiquity.


Author: Laura Geggel | Source: LiveScience [December 14, 2018]



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Byzantine stone relief found in central Turkey

A stone artefact discovered in Turkey’s central Konya province last month was identified as a relief of Biblical figure Daniel.











Byzantine stone relief found in central Turkey
Credit: AA

The artefact – unearthed during the construction of a house in Konya’s Doğanhisar district in November – is currently on display in Akşehir Museum, where it has attracted great attention due to its rarity.


Ilker Mete Mimiroğlu, an arts professor at Konya’s Necmettin Erbakan University, said that the “important and rare” relief dates back to fifth century AD.


“The figure includes a cross motif in the form of a ship’s anchor. Perhaps it relates to fishing in the district,” he said.


Mimiroğlu said the Daniel stone is from the same era as a rare gravestone depicting the story of the Prophet Jonah being swallowed by the giant fish, which is now on display in the Konya Archaeology Museum in Beyşehir.


He said the Jonah stone is “one of the most important artefacts of that period,” adding that these artefacts are “especially important for the Christian world.”


Source: Daily Sabah [December 14, 2018]



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French archaeological mission discovers Neolithic artefacts in Umm Al Quwain

A French archaeological mission has concluded its excavation project in Umm Al Quwain for the current season with the completion of test trenches in eight new archaeological sites.











French archaeological mission discovers Neolithic artefacts in Umm Al Quwain
Credit: WAM

The work has been undertaken in collaboration with the Department of Tourism and Antiquities of Umm Al Quwain. The mission’s excavations resulted in the discovery of a number of artefacts.


Alia Al Ghafli, Director-General of the Department of Tourism and Antiquities of Umm Al Quwain, said that the new excavations are an excellent addition to Umm Al Quwain’s archaeological map.


Samples have been sent to the laboratory of the Sorbonne University in France for Carbon-14 analysis, to accurately date these sites.


Rania Hussain Qanouma, Director of the Antiquities Section at the Department, explained that the sites date back to the Neolithic period. Stone items as well as fragments of pottery from the Ubaid civilisation of Mesopotamia (Iraq) are among the finds.


Author: Hazem Hussein | Source: United Emirates News Agency [December 14, 2018]



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Cemetery with banquet area to honour dead discovered in Peru’s El Chorro...

A cemetery with a banquet area to commemorate the dead was discovered at El Chorro archaeological site, located in Chiclayo’s Pomalca district in northern Peru, said Edgar Bracamonte, the person responsible for the Lambayeque Valley Archaeological Project.











Cemetery with banquet area to honour dead discovered in Peru's El Chorro archaeological site
Credit: Central European News

This burial ground was used between the final stage of the Mochica culture (AD 800-1000) and the end of the Lambayeque culture. The archaeological complex is situated in Chiclayo’s Pomalca district.
A total of 32 graves have been unveiled so far, 23 of which date back to the final stage of the Mochica culture (Middle Horizon) and nine belong to the Lambayeque civilization.


Cemetery with banquet area to honour dead discovered in Peru's El Chorro archaeological site

Cemetery with banquet area to honour dead discovered in Peru's El Chorro archaeological site

Cemetery with banquet area to honour dead discovered in Peru's El Chorro archaeological site










Cemetery with banquet area to honour dead discovered in Peru's El Chorro archaeological site
Credit: Central European News

“The importance of this cemetery is evidenced by the quantity and density of its tombs, plus the number of feasts held there,” he affirmed.
The archaeologist highlighted the discovery of a female mummy —among many graves of women and youth— along with textile tools and a ceremonial copper metal knife typical of the Lambayeque culture.


Cemetery with banquet area to honour dead discovered in Peru's El Chorro archaeological site

Cemetery with banquet area to honour dead discovered in Peru's El Chorro archaeological site

Cemetery with banquet area to honour dead discovered in Peru's El Chorro archaeological site










Cemetery with banquet area to honour dead discovered in Peru's El Chorro archaeological site
Credit: Andina

“Apparently, it was an offering representing a sort of lineage or hierarchy within the group because the object —considered an element of differentiation— was seen only in that grave,” he underlined.


Bracamonte indicated there is a pattern in the body of about 17 children: Their feet were cut up on purpose.


“We have to bring two more to the surface, and an adult whose hand was cut up and placed near his feet. We are going to find out the gender and age with a physical anthropology study,” he pointed out.


It must be noted excavations at the Chiclayo-based site started two months ago.


Source: Andina [December 14, 2018]



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Calcite | #Geology #GeologyPage #Mineral Locality: Kharan,…


Calcite | #Geology #GeologyPage #Mineral


Locality: Kharan, Baluchistan, Pakistan


Size: 7 × 5.8 × 3.5 cm


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Fragmenting Disk Gives Birth to Binary Star ‘Odd Couple’



Artists impression of the disk of dust and gas surrounding the massive protostar MM 1a, with its companion MM 1b forming in the outer regions. Credit: J. D. Ilee / University of Leeds.



Observation of the dust emission (green) and the cool gas around MM1a (red is receding gas, blue is approaching gas), indicating that the outflow cavity rotates in the same sense as the central accretion disc. MM1b is seen orbiting in the lower left. Credit: ALMA (ESO/NAOJ/NRAO); J. D. Ilee / University of Leeds.



Observation of the dust emission (green) and hot gas rotating in the disc around MM 1a (red is receding gas, blue is approaching gas). MM 1b is seen the lower left. Credit: ALMA (ESO/NAOJ/NRAO); J. D. Ilee / University of Leeds.


Astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) have discovered that two young stars forming from the same swirling protoplanetary disk may be twins — in the sense that they came from the same parent cloud of star-forming material. Beyond that, however, they have shockingly little in common.



The main, central star of this system, which is located approximately 11,000 light-years from Earth, is truly colossal — a full 40 times more massive than the Sun. The other star, which ALMA recently discovered just beyond the central star’s disk, is a relatively puny one-eightieth (1/80) that mass.


Their striking difference in size suggests that they formed by following two very different paths. The more massive star took the more traditional route by collapsing under gravity out of a dense “core” of gas. The smaller one likely followed the road less traveled by – at least for stars – by accumulating mass from a portion of the disk that “fragmented” away as it matured, a process that may have more in common with the birth of gas-giant planets.


“Astronomers have known for a long time that most massive stars orbit one or more other stars as partners in a compact system, but how they got there has been a topic of conjecture,” said Crystal Brogan, an astronomer with the National Radio Astronomy Observatory (NRAO) in Charlottesville, Virginia, and a co-author on the study. “With ALMA, we now have evidence that the disk of gas and dust that encompasses and feeds a growing massive star also produces fragments at early stages that can form a secondary star.”


The main object, known as MM 1a, is a previously identified young massive star surrounded by a rotating disk of gas and dust. A faint protostellar companion to this object, MM 1b, was newly detected by ALMA just outside the MM 1a protoplanetary disk. The team believes this is one of the first examples of a fragmented disk to be detected around a massive young star.


“This ALMA observation opens new questions, such as ‘Does the secondary star also have a disk?’ and ‘How fast can the secondary star grow?’ The amazing thing about ALMA is that we have not yet used its full capabilities in this area, which will someday allow us to answer these new questions,” said co-author Todd Hunter, who is also with the NRAO in Charlottesville.


Stars form within large clouds of gas and dust in interstellar space. When these clouds collapse under gravity, they begin to rotate faster, forming a disk around them.


“In low-mass stars like our Sun, it is in these disks that planets can form,” said John Ilee, an astronomer at Leeds University in England and lead author on the study. “In this case, the star and disk we have observed are so massive that, rather than witnessing a planet forming in the disk, we are seeing another star being born.”


By observing the millimeter wavelength light naturally emitted by the dust, and subtle shifts in the frequency of light emitted by the gas, the researchers were able to calculate the mass of MM 1a and MM 1b.


Their work is published in the Astrophysical Journal Letters.


“Many older massive stars are found with nearby companions,” added Ilee. “But binary stars are often very equal in mass, and so likely formed together as siblings. Finding a young binary system with a mass ratio of 80-to-1 is very unusual and suggests an entirely different formation process for both objects.”


The favored formation process for MM 1b occurs in the outer regions of cold, massive disks. These “gravitationally unstable” disks are unable to hold themselves up against the pull of their own gravity, collapsing into one – or more – fragments.


The researchers note that newly discovered young star MM 1b could also be surrounded by its own circumstellar disk, which may have the potential to form planets of its own – but it will need to be quick.  “Stars as massive as MM 1a only live for around a million years before exploding as powerful supernovae, so while MM 1b may have the potential to form its own planetary system in the future, it won’t be around for long,” Ilee concluded.

Additional Information


This research was published in the Astrophysical Journal Letters in an article titled “G11.92–0.61 MM 1: A Fragmented Keplerian Disk Surrounding a Proto-O Star” by J. D. Ilee.


The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of the European Southern Observatory (ESO), the U.S. National Science Foundation (NSF) and the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Republic of Chile. ALMA is funded by ESO on behalf of its Member States, by NSF in cooperation with the National Research Council of Canada (NRC) and the Ministry of Science and Technology (MOST) in Taiwan and by NINS in cooperation with the Academia Sinica (AS) in Taiwan and the Korea Astronomy and Space Science Institute (KASI).


ALMA construction and operations are led by ESO on behalf of its Member States; by the National Radio Astronomy Observatory (NRAO), managed by Associated Universities, Inc. (AUI), on behalf of North America; and by the National Astronomical Observatory of Japan (NAOJ) on behalf of East Asia. The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.




Contacts

Nicolás Lira
Education and Public Outreach Coordinator
Joint ALMA Observatory, Santiago – Chile
Phone: +56 2 2467 6519
Cell phone: +56 9 9445 7726
Email: nicolas.lira@alma.cl


Charles E. Blue
Public Information Officer
National Radio Astronomy Observatory Charlottesville, Virginia – USA
Phone: +1 434 296 0314
Cell phone: +1 202 236 6324
Email: cblue@nrao.edu


Calum Turner
ESO Assistant Public Information Officer
Garching bei München, Germany
Phone: +49 89 3200 6670
Email: calum.turner@eso.org


Masaaki Hiramatsu
Education and Public Outreach Officer, NAOJ Chile
Observatory
, Tokyo – Japan
Phone: +81 422 34 3630







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4,000-year-old board game discovered in floor of shelter in Azerbaijan

A series of marks in the floor of a rock shelter in Azerbaijan may look like an undecipherable ancient code, but one archaeologist says he has cracked it.











4,000-year-old board game discovered in floor of shelter in Azerbaijan
A distinctive pattern of holes scored into the rock of an ancient shelter in Azerbaijan are the remains of a board
 for one of the world’s oldest games [Credit: Walter Crist/Gobustan National Park]

Walter Crist, from the American Museum of Natural History, said it was a board game, played by ancient nomads who mustered cattle in the region roughly 4,000 years ago.


“Small depressions found pecked into bedrock as well as on stone slabs found during excavation are arranged in a recurring and unique pattern,” Dr Crist said.


“[It] is strikingly similar to the well-known game of 58 Holes, colloquially known as Hounds and Jackals.”


Hounds and Jackals was a game popular in ancient Egypt and Mesopotamia, a cultural hub in southwestern Asia, near modern-day Syria.


Finding a 4000-year-old version of the game in Azerbaijan, in the UNESCO World Heritage listed Gobustan National Park, was something of a surprise, as there was no known evidence the game was played there during that time.


The discovery suggests there was contact between the ancient dwellers of the land and their distant neighbours.











4,000-year-old board game discovered in floor of shelter in Azerbaijan
Archaeologists say that the rock shelter and it’s ancient game board were used by nomadic cattle herders
during the Bronze Age, about 4,000 years ago [Credit: Walter Crist/Gobustan National Park]

“Bronze Age herders in that region must have had contacts with the Near Eastern world,” Dr Crist said. “Ancient games often passed across cultures and acted as a social lubricant.”


Dr Crist discovered the ancient game while searching for examples of Hounds and Jackals, spotting what looked like a version of the game in Azerbaijan in an online magazine.


He arranged to visit the site in photograph, but it had been dug up for a housing development by the time he arrived.


An official told Dr Crist there was a similar pattern in the famed UNESCO national park, with the American archaeologist immediately recognising the markings when he visited the site.


Hounds and Jackals has been likened to an early version of backgammon, believed to be a two-player game with the goal of moving markers along a dotted track towards a finishing point.


As there are no boxes with instructions on the back, researchers can’t know the rules or end goal of the game for sure.


However, Dr Crist said the overarching goal of the act of playing the game was recreation and human connection.


“Moving stones in blank spaces on the ground has no real effect on your daily life, except for the fact that it helps you interact with another person,” he told Live Science.


“So, a game is a tool for interaction, kind of like language — a shared way of being able to interact with people.”


Source: ABC News Website [December 15, 2018]



TANN



Archive


First Stone Age farmers in Norway “gave up” after short period of time

Agriculture came to Scandinavia for the first time during the final stages of the Late Neolithic period, around 3900 to 1800 BCE. But there are still so many unanswered questions about life in Norway at the time.











First Stone Age farmers in Norway "gave up" after short period of time
The excavation of Slettabø in Rogaland county, Norway, 1977. An important Neolithic site for understanding the Norwegian
 Early Stone Age. The thick cultural layers (dark, coal-bearing layers) are bounded by layers of aeolian sand
[Credit: from www.unimus.no]

How did people live? Were they influenced by other peoples in Europe? These are the kinds of questions explored by Svein Vatsvåg Nielsen and colleagues from the University of Oslo’s Museum of Cultural History in a new study published in the Journal of Anthropological Archaeology.


“We opted to use a lot of archaeological data at once to see if it could tell us anything about changes in the population and in the intensity of human activity,” he says.


Nielsen and his colleagues have studied data from previous excavations in the eastern, central, and western parts of Norway.


“In recent years the methods used to analyse large datasets have undergone major developments. Computer program and computer power development make it possible for us to look at the old data in a new way,” says Nielsen.


Arrowheads and nutshells


They studied 643 samples, which were previosuly dated using radiocarbon, as well as archaeological objects from around 200 sites around Norway.


The samples included fireplaces, cooking pits, building remains, and burnt nutshells. Studying the distribution of radiocarbon dated material allowed them to analyse populaiton changes during the Late Neolithic.


Migration wave spread northward from Middle East


The first people who started farming came from the Middle East around 11,500 years ago, where they began to keep animals and grow crops.


“An old theory states that people who farmed, had more children and more stable lives than people who lived as hunter and gatherers,” says Nielsen.


Some residents emigrated, and some may have fled due to overcrowding pressures.


“According to this theory, the migrations led to a very slow wave across Europe. We wanted to see if we could find traces of this wave in Norway. So it made sense for us to compare eastern Norway with the surrounding regions,” Nielsen says.











First Stone Age farmers in Norway "gave up" after short period of time
Here are examples of objects found from the Late Neolithic period
[Credit: Svein Vatsvåg Nielsen]

The oldest farming culture in Scandinavia probably became established around 3,900 BCE. Norway was rather late in the game, but researchers believe they can also see traces of this ‘wave’ reaching Norway at the beginning of the Late Neolithic.


The indications are clearest in Eastern Norway, where a blossoming of activity indicates the arrival of more people in the area. Whether local hunters learned a few tricks from their neighbours to the south, or migrants displaced the fisher culture, is hard to say. Future DNA analysis of skeletons may eventually provide some answers.


“We think this increased activity was due to the first farming societies that grew up around and north of the Oslo Fjord during this period,” Nielsen says.


However, direct evidence of agriculture does not exist in the archaeological material.


“The soil in Eastern Norway is very acidic and the traces of cultivation have been poorly preserved. It’s been ploughed over for hundreds of years so any old traces have mostly disappeared,” he says.


The distribution of a certain type of axe suggests that farming was taking place in Eastern Norway during this period.


Fishing settlements dotted along the coast


But while people eslewhere in Europe had gotten the hang of cultivating crops and keeping livestock, the first farmers in Norway appear to have given up relatively early. They stopped growing crops after a relatively short period of time and returned to hunter-gatherer-fisher lifestyle.


The first period of apparent population growth, was followed by a long period of 1,500 years with less activity and a subsequent population decline. Whether the challenges were related to the climate in Norway or other factors is unclear.


However, settlements in the coastal areas grew and were strongly linked to the sea, where food was plentiful.


Characteristic ceramic objects tell the story of a maritime culture.


Nielsen says the arguments have gone back and forth as to why people returned to a fishing culture or gave up farming. Some think its an obvious way to live, given the country’s huge coastal resources. On the other hand, why would the people who introduced agriculture end it? Espeically when they were probably familiar with it in northern Germany and Denmark.


Some hardy, or perhaps hard-headed, types also stayed in the mountains and along the coast of central Norway. But there are even fewer findings in these places.


Big changes towards the end of Late Neolithic


Towards the end of the Late Neolithic period, researchers again saw changes in the population.


“The settlement pattern changes very clearly when we approach 5,300 years ago. Coastal sites fall out of use, and long houses and grains begin to show up. We start to see a type of settlement that we recognise from the Bronze Age and Iron Age,” says Nielsen.


Farming society began to take shape. A little later, immigrants from the Bell Beaker culture along the coast came and brought new technology, customs, and culture. The Bronze Age was at hand.


Studying all of the Late Neolithic archaeolgical sites throughout southern Norway collectively, confirms the results of previous studies: Agriculture seems to have been introduced in Norway twice, and the second time it came to stay.


“We think our results show that major changes in the population size occurred during the Late Neolithic, which in itself is very interesting. We can’t count people so we have to use other inputs to these questions. If you accept this premice, then we believe we have data that confirms this,” says Nielsen.

This article was originally published on ScienceNordic. Read the original here.


Author: Ingrid P. Nuse (based on an article by Elise Kjørstad) | Source: ScienceNordic [December 15, 2018]



TANN



Archive


The life and death of a planetary system

How did we get here? How do stars and planets come into being? What happens during a star’s life, and what fate will its planets meet when it dies?











The life and death of a planetary system
The Eagle Nebula is a famous example of a cloud where stars are born. This area is called the Pillars of Creation
[Credit: NASA, ESA and the Hubble Heritage Team (STScI/AURA)]

Our story begins with unimaginably cold clouds in space that contain the seeds of whole new worlds – stars and planets about to be born.



What happens next? Find out in this new multimedia experience.


Author: Elizabeth Landau | Source: NASA [December 16, 2018]



TANN



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