среда, 20 марта 2019 г.

Researchers make a key discovery on how alpine streams work

An EPFL study has prompted scientists to rethink a standard approach used to calculate the velocity of gas exchange between mountain streams and the atmosphere. Research conducted in streams in Vaud and Valais indicate that equations used to predict gas exchange based on data from lowland streams undershoots the actual gas exchange velocity in mountain streams on average by a factor of 100.











Researchers make a key discovery on how alpine streams work
Alpine stream in Canton Valais, in Switzerland [Credit: © SBER/EPFL]

This discovery – appearing in Nature Geoscience – will enable scientists to develop more accurate models of the role that mountain streams play in global biogeochemical fluxes. Considering that more than 30% of the Earth’s surface is covered by mountains, the ramifications of this discovery are considerable.


The study was conducted at EPFL’s Stream Biofilm and Ecosystem Research Laboratory (SBER), within the School of Architecture, Civil and Environmental Engineering (ENAC).


More turbulence


In aquatic ecosystems, such as the world’s oceans, streams and lakes, numerous aquatic organisms, ranging from bacteria to fish, respire oxygen and exhale CO2. These gases must therefore be continually “exchanged” from the atmosphere to the water and vice-versa. Because mountain streams often flow over steep drops and rugged terrain, this creates a lot of turbulence and causes air bubbles to be trapped in the water, appearing white (aka ‘white water’).


These bubbles accelerate the gas exchange. Strikingly, the same mechanism is at work when white-capped waves appear on the surface of rough seas. Until now, scientists have ignored the contribution from air bubbles and have used the same approach to calculate gas exchange velocities in mountain streams than in calm lowland streams.


More precise calculations


It is intuitive that the rugged terrain would influence gas exchange in mountain streams, but no evidence had been collected to test this hypothesis until 2016. That’s when EPFL researchers installed more than 130 environmental sensors in mountain streams in Vaud and Valais to study this physical phenomena and related biogeochemical fluxes. To measure gas exchange velocity as accurately as possible, one of the SBER scientists and first author of the study – Amber Ulseth – along with others, added small amounts of argon as a tracer gas to the streams. Argon is a naturally occurring gas that is harmless to aquatic ecosystems.


Using cutting-edge analytical methods in the laboratory, Amber Ulseth and colleagues were able to quantify loss of argon from the streamwater. Next, they modeled the gas exchange velocity from the downstream loss of the tracer gas in the streamwater. Their results reveal that the gas exchange velocity in mountain streams is on average 100 times higher than predicted from equations developed from similar tracer gas experiments in low-land streams.


Major implications


“Our findings have major implications. They suggest that we have been underestimating the effects of all the small but abundant mountain streams in our biogeochemical models. This opens up a new research avenue,” says Tom Battin, Director of SBER and coauthor of the study. His lab is already looking into extensions of this research, such as developing a new model to predict CO2 emissions from mountain streams worldwide.


Source: Ecole Polytechnique Fédérale de Lausanne [March 18, 2019]



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Algal library lends insights into genes for photosynthesis

It isn’t easy being green. It takes thousands of genes to build the photosynthetic machinery that plants need to harness sunlight for growth. And yet, researchers don’t know exactly how these genes work.











Algal library lends insights into genes for photosynthesis
To build the library, researchers grew tens of thousands of strains of algae in plastic plates. The project, which took
nine years, allows researchers to explore genes involved in photosynthesis and other aspects of plant biology
[Credit: Xiaobo Li et al. 2019]

Now a team led by Princeton University researchers has constructed a public “library” to help researchers to find out what each gene does. Using the library, the team identified 303 genes associated with photosynthesis including 21 newly discovered genes with high potential to provide new insights into this life-sustaining biological process. The study was published online this week in Nature Genetics.


“The part of the plant responsible for photosynthesis is like a complex machine made up of many parts, and we want to understand what each part does,” said Martin Jonikas, assistant professor of molecular biology at Princeton. “This library, we hope, will be one of the foundations that people will build on to make the next generation of discoveries.”


Unlocking the role of each gene could allow researchers to engineer plants to grow more quickly, potentially meeting future world food needs. Plants could also potentially be altered to absorb more carbon dioxide, helping to address climate challenges.


The library, funded in large part through a grant from the National Science Foundation, consists of thousands of single-celled, pond-dwelling algae known as Chlamydomonas reinhardtii, or Chlamy for short. Each “book” in the library is a strain of Chlamy with a single mutation. The 62,000-plus mutant strains, housed at the University of Minnesota’s Chlamydomonas Resource Center, cover more than 80 percent of Chlamy’s genes.


Similar libraries have been made in other single-celled organisms, such as yeast, but this is the first such endeavor for any single-celled photosynthetic organism. The rapid growth of single-celled organisms makes them valuable as research tools.


“Because this algal species is often used as a model to understand a wider range of biological processes, this library will be an important resource,” said Karen Cone, a program director at the National Science Foundation, which was the primary funder for this research. “The partnership between the Jonikas group and the Chlamydomonas Resource Center enhances community accessibility to this valuable resource, which in turn will enable new discoveries, especially in one of NSF’s research priority areas, ‘Understanding the Rules of Life.'”


Due to various challenges inherent in Chlamy’s genome, the project took nine years to complete. Throughout the project, researchers used robots to keep generations of cells alive by changing the nutrient-rich liquid media in which they live.


The project started in 2010 while Jonikas and his team were at the Carnegie Institution for Science on the Stanford University campus, and was completed at Princeton where the Jonikas laboratory moved in 2016. The project was a collaboration with Arthur Grossman, a senior staff scientist at Carnegie and with the Chlamydomonas Resource Center run by Paul Lefebvre, a professor of plant and microbial biology at the University of Minnesota.


The ability to observe a Chlamy cell with just one defective gene among all the other functioning genes allows researchers to figure out what that gene does. For example, if the cell has trouble moving, then the defective gene’s function mostly likely involves governing movement.


Jonikas compared the Chlamy mutant library to a library containing thousands of copies of a manual for constructing a car, with each copy missing a different section. No matter which manual was used, the resulting car would be missing a part, making it unable to operate as expected.


“The horn might not work, or the steering wheel might not turn,” Jonikas said. “Then you would know that the missing section contained the instructions for that part of the car.”


The library enables researchers to test multiple mutant Chlamy strains at once because each mutation is labeled with a unique “DNA barcode.” For the current study, investigators placed thousands of Chlamy strains in a single flask and exposed them to light. Strains that failed to grow were more likely to contain a gene involved in photosynthesis.


One of the newly identified genes is CPL3, which is thought to play a role in accumulating the protein “parts” of the photosynthetic machinery. The team is now exploring whether the gene helps the algae adjust their photosynthetic activity to changes in sunlight levels.


The mutant library can enable studies in other areas of plant biology, such as intracellular communication and Chlamy’s ability to paddle around its environment using a tail-like cilium.


Xiaobo Li, the study’s first author, was a postdoctoral researcher at Princeton when the team completed the library. “It is our hope that the Chlamydomonas mutant library and the genes identified will lead to numerous fundamental discoveries in photosynthesis, cell motility and many other processes,” Li said.


Weronika Patena, a senior bioinformatics analyst in the Jonikas laboratory, wrote computer programs to analyze large amounts of data to identify genes most likely to be involved in photosynthesis. “I believe the success of this project will greatly accelerate research into photosynthesis and other processes for which Chlamy is a good model, and provide a lot of value to the scientific community,” she said.


Source: Princeton University [March 18, 2019]



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Rukwa Rift Basin Project names new Cretaceous mammal from East African Rift System

Ohio University researchers announced a new species of mammal from the Age of Dinosaurs, representing the most complete mammal from the Cretaceous Period of continental Africa, and providing tantalizing insights into the past diversity of mammals on the planet.











Rukwa Rift Basin Project names new Cretaceous mammal from East African Rift System
Side view of the lower jaw of Galulatherium jenkinsi, the most complete mammal yet know from the Cretaceous
Period of the African continent, and named this week by researchers from Ohio University
[Credit: Patrick O’Connor et al. 2019]

The National Science Foundation-funded OHIO team, in collaboration with international colleagues, identified and named the new mammal in an article published in Acta Paleontologica Polonica. This nearly complete lower jaw represents the first named mammal species from the Late Cretaceous Period (100-66 million years ago) of the entire African continent. The squirrel-sized animal was probably related to a group of southern hemisphere mammals known as gondwanatherians, yet a bizarre combination of features (including evergrowing and enamel-less peg-like teeth) make it challenging to easily place within any group of mammals yet known, living or extinct.


The new mammal is named Galulatherium jenkinsi, a name based on the Galula rock unit (itself derived from one of the local villages in the field area) and therium, Latin for beast, with the species name “jenkinsi” honoring the late Farish Jenkins, distinguished professor of anatomy and organismic biology at Harvard University and a strong supporter of the Rukwa Rift Basin Project early in its development.


The type and only specimen of Galulatherium was discovered in 2002, when Rukwa Rift Basin Project researchers found a bone fragment eroding from Cretaceous-age red sandstones in the Rukwa Rift Basin in southwestern Tanzania. After painstakingly removing the rock from the delicate specimen, the team announced the discovery of a new mammal in 2003, yet they conservatively refrained from establishing a name for the enigmatic new species until additional details of its anatomy could be revealed. In the intervening years, improvements in high-resolution x-ray computed tomography enabled the team to document detailed anatomy of the specimen and to establish Galulatherium as a species new to science.


“The analysis of Galulatherium has been a collaborative process, engaging with a group of experts to tackle the unique morphology of this specimen,” noted Dr. Patrick O’Connor, professor of anatomy at Ohio University and lead author of the paper. “Additional information gleaned from density-based microCT analyses, particularly the presence of ever-growing, enamel-less teeth, has allowed us to compare Galulatherium with other Mesozoic and early Cenozoic mammals, as well as with modern groups like sloths, in order to establish the best anatomical and functional analogs for this unique type of dentition.”


Rotating view of the lower jaw of the Galulatherium jenkinsi, the most complete mammal yet know from the 


Cretaceous Period of the African continent, and named this week by researchers from Ohio University 


[Credit: Patrick O’Connor et al. 2019] 


Gonwanatherian mammals are best known from Cretaceous and early Cenozoic rock units in Madagascar and Argentina, with other specimens known from India and Antarctica. Members of the research team have worked across the globe in search of early mammals.


“The fact that this is the first discovery of an identifiable mammal fossil in the Late Cretaceous of all of mainland Africa is incredibly exhilarating on so many levels,” added co-author David Krause, curator of paleontology at the Denver Museum of Nature and Science. “The needle is very small and the haystack is very big. And we know that there are so many more needles to find there.”


The perplexing story of Galulatherium and identifying its closest relatives is just the starting point. Getting ANY insight into what mammals lived on the continent during this time is groundbreaking, but it seems that Galulatherium is not a predecessor of any of the mammals that live on Africa today. So what happened to it and its kin? Were they wiped out at the end of the Cretaceous? When did the ancestors of Africa’s extant mammalian lineages arrive on the continent? Or were they living alongside Galulatherium and just have not yet been found?


“All great questions that will only be answered with the discovery of additional fossils, underscoring the need for exploratory research in places like the Rukwa Rift Basin and elsewhere on the continent,” added O’Connor.


The study included experts from several institutions to pore over the tiny jaw. Yet the specimen preserved a truly unique combination of anatomical features, making it difficult to place in the existing framework of mammalian evolution, and ultimately raising more questions than it answers.


“What began with the description of a compact specimen became a broader quest to understand how this jaw fits into the complex puzzle of mammalian evolution,” said Dr. Nancy Stevens, Ohio University professor and co-author on the paper.


Galulatherium is not the only animal discovered by the research team in the Rukwa Rift Basin. Other Cretaceous-age finds include bizarre relatives of early crocodiles and three distinct species of long-necked herbivorous sauropod dinosaurs. Finds from younger rocks in the region contain the oldest evidence of the split between monkeys and apes. Taken together, these findings from the East African Rift reveal a crucial glimpse into ancient ecosystems of Africa and encourage additional field exploration on the continent.


Other Cretaceous findings by the Rukwa Rift Basin Project research team in the Rukwa Rift Basin include:


– Mnyamawantuka moyowamkia – titanosaurian sauropod dinosaur, Rukwa Rift Basin
– Shingopana songwensis – titanosaurian sauropod dinosaur, Rukwa Rift Basin
– Rukwatitan bisepultus – titanosaurian sauropod dinosaur, Rukwa Rift Basin
– Pakasuchus kapilimai–mammal-like crocodile, Rukwa Rift Basin


The team has also made discoveries in the younger Paleogene deposits of the Rukwa Rift Basin:


– Early evidence for monkey-ape split, Rukwa Rift Basin
– Oldest fossil evidence of venomous snakes, Rukwa Rift Basin
– Early evidence of insect farming–Fossil Termite Nests, Rukwa Rift Basin
– Bobcat-sized carnivore, Rukwa Rift Basin


Source: Ohio University [March 18, 2019]



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Mammals’ unique arms started evolving before the dinosaurs existed

Bats fly, whales swim, gibbons swing from tree to tree, horses gallop, and humans swipe on their phones–the different habitats and lifestyles of mammals rely on our unique forelimbs. No other group of vertebrate animals has evolved so many different kinds of arms: in contrast, all birds have wings, and pretty much all lizards walk on all fours. Our forelimbs are a big part of what makes mammals special, and in a new study in the Proceedings of the National Academy of Sciences, scientists have discovered that our early relatives started evolving diverse forelimbs 270 million years ago–a good 30 million years before the earliest dinosaurs existed.











Mammals' unique arms started evolving before the dinosaurs existed
Thrinaxodon, a therapsid animal related to today’s mammals. The therapsids are the group where
mammal relatives began developing diverse forelimbs [Credit: (c) April I. Neander]

“Aside from fur, diverse forelimb shape is one of the most iconic characteristics of mammals,” says the paper’s lead author Jacqueline Lungmus, a research assistant at Chicago’s Field Museum and a doctoral candidate at the University of Chicago. “We were trying to understand where that comes from, if it’s a recent trait or if this has been something special about the group of animals that we belong to from the beginning.”


To determine the origins of mammals’ arms today, Lungmus and her co-author, Field Museum curator Ken Angielczyk, examined the fossils of mammals’ ancient relatives. About 312 million years ago, land-dwelling vertebrates split into two groups–the sauropsids, which went on to include dinosaurs, birds, crocodiles, and lizards, and the synapsids, the group that mammals are part of.


A key difference between sauropsids and synapsids is the pattern of openings in the skull where jaw muscles attach. While the earliest synapsids, called pelycosaurs, were more closely related to humans than to dinosaurs, they looked like hulking reptiles. Angielczyk notes, “If you saw a pelycosaur walking down the street, you wouldn’t think it looked like a mammal–you’d say, ‘That’s a weird-looking crocodile.'”


About 270 million years ago, though, a more diverse (and sometimes furry) line of our family tree emerged: the therapsids. “Modern mammals are the only surviving therapsids–this is the group that we’re part of today,” explains Lungmus. Therapsids were the first members of our family to really branch out–instead of just croc-like pelycosaurs, the therapsids included lithe carnivores, burly-armed burrowers, and tree-dwelling plant-eaters.











Mammals' unique arms started evolving before the dinosaurs existed
Photographs of the upper arm bones from seven kinds of early mammal relatives. The three bones on the left are from
an early group called pelycosaurs, and the bones are all roughly the same shape. The four bones on the right are
from therapsids, the group that includes today’s mammals, and they show the greater variety of
shapes and sizes that characterize therapsid limbs. The black scale bars represent 2cm
[Credit: (c) Jacqueline Lungmus, Field Museum]

Lungmus and Angielczyk set out to see if this explosion of diversity came with a corresponding explosion in different forelimb shapes. “This is the first study to quantify forelimb shape across a big sample of these animals,” says Lungmus. The team examined the upper arm bones of hundreds of fossil specimens representing 73 kinds of pelycosaurs and therapsids, taking measurements near where the bones joined the shoulder and the elbow. They then analyzed the shapes of the bones using a technique called geometric morphometrics.
When they compared the shapes of arm bones, the researchers found a lot more variation in the bones of the therapsids than the pelycosaurs. They also noted that the upper part of the arm, near the shoulder, was especially varied in therapsids–a feature that might have let them move more freely than the pelycosaurs, whose bulky and tightly-fitting shoulder bones likely gave them a more limited range of motion.


Lungmus and Angielczyk found that a wide variety of different forelimb shapes evolved within the therapsids 270 million years ago. “The therapsids are the first synapsids to increase the variability of their forelimbs– this study dramatically pushes that trait back in time,” says Lungmus. Prior to this study, the earliest that paleontologists had been able to definitively trace back mammals’ diverse forelimbs was 160 million years ago. With Lungmus and Angielczyk’s work, that’s been pushed back by more than a hundred million years.











Mammals' unique arms started evolving before the dinosaurs existed
Ophiacodon, an early mammal relative from before the group began developing diverse forelimbs
[Credit: (c) April I. Neander]

The researchers note that the study helps explain how mammals evolved traits that have made us what we are today. “So much of what we do every day is related to the way our forelimbs evolved–even simple things like holding a phone,” says Angielczyk.


“This is something that’s so cool about our evolutionary lineage,” says Lungmus. “These animals are in the same group as us–part of what makes this research compelling is that these are our relatives.”


Source: Field Museum [March 18, 2019]



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Earliest known Mariner’s Astrolabe certified

Guinness World Records have independently certified an astrolabe excavated from the wreck site of a Portuguese Armada Ship that was part of Vasco da Gama’s second voyage to India in 1502-1503 as the oldest in the world, and have separately certified a ship’s bell (dated 1498) recovered from the same wreck site also as the oldest in the world.











Earliest known Mariner's Astrolabe certified
Guinness World Records have independently certified an astrolabe excavated from the wreck site of a Portuguese
 Armada Ship that was part of Vasco da Gama’s second voyage to India in 1502-1503 as the oldest in the world, 
and have separately certified a ship’s bell (dated 1498) recovered from the same wreck site also 
as the oldest in the world [Credit: David Mearns]

The scientific process of verifying the disc as an astrolabe by laser imaging is described in a paper published today by Mearns and Jason Warnett and Mark Williams of WMG at the University of Warwick in the International Journal of Nautical Archaeology.


The Sodré astrolabe has made it into the Guinness Book of world records is believed to have been made between 1496 and 1501 and is unique in comparison to all other mariner’s astrolabes.


Mariner’s Astrolabes were used for navigating at sea by early explorers, most notably the Portuguese and Spanish.


They are considered to be the rarest and most prized of artefacts to be found on ancient shipwrecks and only 104 examples are known to exist in the world.











Earliest known Mariner's Astrolabe certified

Guinness World Records have independently certified an astrolabe excavated from the wreck site of a Portuguese


 Armada Ship that was part of Vasco da Gama’s second voyage to India in 1502-1503 as the oldest in the world, 


and have separately certified a ship’s bell (dated 1498) recovered from the same wreck site also 


as the oldest in the world [Credit: David Mearns]



They were first used at sea on a Portuguese voyage down the west coast of Africa in 1481. Thereafter, astrolabes were relied on for navigation during the most important explorations of the late 15th century, including those led by Bartolomeu Dias, Christopher Columbus and Vasco da Gama.


It is the only solid disk type astrolabe with a verifiable provenance and the only specimen decorated with a national symbol: the royal coat of arms of Portugal.


As the earliest verifiable mariner’s astrolabe it fills a chronological gap in the development of these iconic instruments and is believed to be a transitional instrument between the classic planispheric astrolabe and the open-wheel type astrolabe that came into use sometime before 1517.


The thin 175 mm diameter disk weighing 344 grams was analysed by a team from WMG who travelled to Muscat, Oman in November 2016 to collect laser scans of a selection of the most important artefacts recovered from the wreck site.











Earliest known Mariner's Astrolabe certified

Guinness World Records have independently certified an astrolabe excavated from the wreck site of a Portuguese


 Armada Ship that was part of Vasco da Gama’s second voyage to India in 1502-1503 as the oldest in the world, 


and have separately certified a ship’s bell (dated 1498) recovered from the same wreck site also 


as the oldest in the world [Credit: David Mearns]



Using a portable 7-axis Nikon laser scanner, capable of collecting over 50,000 points per second at an accuracy of 60 microns, a 3D virtual model of the artefact was created.


Analysis of the results revealed a series of 18 scale marks spaced at uniform intervals along the limb of the disk.


Further analysis by WMG engineers showed that the spacing of the scale marks was equivalent to 5-degree intervals. This was critical evidence that allowed independent experts at Texas A&M University to include the disk in their global inventory as the earliest known mariner’s astrolabe discovered to date.


Prof Mark Williams from WMG, University of Warwick comments: “Using this 3D scanning technology has enabled us to confirm the identity of the earliest known astrolabe, from this historians and scientists can determine more about history and how ships navigated.



The earliest known Marnier’s Astroble being discovered by David Mearns 


[Credit: David Mearns ]


Technology like this betters our understanding of how the disc would have worked back in the 15th century. Using technology normally applied within engineering projects to help shed insight into such a valuable artefact was a real privilege”


David Mearns of Blue Water Recoveries Ltd comments: “Without the laser scanning work performed by WMG we would never have known that the scale marks, which were invisible to the naked eye, existed. Their analysis proved beyond doubt that the disk was a mariner’s astrolabe. This has allowed us to confidently place the Sodré astrolabe in its correct chronological position and propose it to be an important transitional instrument.”


Source: University of Warwick [March 18, 2019]



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First Anatolian farmers were local hunter-gatherers that adopted agriculture

An international team, led by scientists from the Max Planck Institute for the Science of Human History and in collaboration with scientists from the United Kingdom, Turkey and Israel, has analyzed 8 pre-historic individuals, including the first genome-wide data from a 15,000-year-old Anatolian hunter-gatherer, and found that the first Anatolian farmers were direct descendants of local hunter-gatherers.











First Anatolian farmers were local hunter-gatherers that adopted agriculture
The burial of a 15,000 year old Anatolian hunter-gatherer [Credit: Douglas Baird]

These findings provide support for archaeological evidence that farming was adopted and developed by local hunter-gatherers who changed their subsistence strategy, rather than being introduced by a large movement of people from another area. Interestingly, while the study shows the long-term persistence of the Anatolian hunter-gatherer gene pool over 7,000 years, it also indicates a pattern of genetic interactions with neighbouring groups.


Farming was developed approximately 11,000 years ago in the Fertile Crescent, a region that includes present-day Iraq, Syria, Israel, Lebanon, Egypt and Jordan as well as the fringes of southern Anatolia and western Iran. By about 8,300 BCE it had spread to central Anatolia, in present-day Turkey. These early Anatolian farmers subsequently migrated throughout Europe, bringing this new subsistence strategy and their genes.


Today, the single largest component of the ancestry of modern-day Europeans comes from these Anatolian farmers. It has long been debated, however, whether farming was brought to Anatolia similarly by a group of migrating farmers from the Fertile Crescent, or whether the local hunter-gatherers of Anatolia adopted farming practices from their neighbours.


A new study by an international team of scientists led by the Max Planck Institute for the Science of Human History and in collaboration with scientists from the United Kingdom, Turkey and Israel, published in Nature Communications, confirms existing archaeological evidence that shows that Anatolian hunter-gatherers did indeed adopt farming themselves, and the later Anatolian farmers were direct descendants of a gene-pool that remained relatively stable for over 7,000 years.


Local hunter-gatherers adopted an agricultural lifestyle


For this study, the researchers newly analyzed ancient DNA from 8 individuals, and succeeded in recovering for the first time whole-genome data from a 15,000-year-old Anatolian hunter-gatherer. This allowed the team to compare that individual’s DNA to later Anatolian farmers, as well as individuals from neighboring regions, to determine how they were related. They also compared the individuals newly analyzed in the study to existing data from 587 ancient individuals and 254 present-day populations.





Video interview with the researchers describing the findings of the publication Feldman et al. 2019. 


Late Pleistocene human genome suggests a local origin for the first farmers of central Anatolia 


[Credit: Max Planck Institute for the Science of Human History]


The researchers found that the early Anatolian farmers derived the vast majority of their ancestry (~90%) from a population related to the Anatolian hunter-gatherer in the study. “This suggests a long-term genetic stability in central Anatolia over five millennia, despite changes in climate and subsistence strategy,” explains Michal Feldman of the Max Planck Institute for the Science of Human History.
“Our results provide additional, genetic support for previous archaeological evidence that suggests that Anatolia was not merely a stepping stone in a movement of early farmers from the Fertile Crescent into Europe,” states Choongwon Jeong of the Max Planck Institute of the Science of Human History, co-senior author of the study. “Rather, it was a place where local hunter-gatherers adopted ideas, plants and technology that led to agricultural subsistence.”


Genetic interactions with neighbours warrant further study


In addition to the long-term stability of the major component of the Anatolian ancestry, the researchers also found a pattern of interactions with their neighbors. By the time that farming had taken hold in Anatolia between 8,300-7,800 BCE, the researchers found that the local population had about a 10% genetic contribution from populations related to those living in what is today Iran and the neighbouring Caucasus, with almost the entire remaining 90% coming from Anatolian hunter-gatherers. By about 7000-6000 BCE, however, the Anatolian farmers derived about 20% of their ancestry from populations related to those living in the Levant region.


“There are some large gaps, both in time and geography, in the genomes we currently have available for study,” explains Johannes Krause of the Max Planck Institute for the Science of Human History, senior author on the study. “This makes it difficult to say how these more subtle genetic interactions took place – whether it was through short-term large movements of people, or more frequent but low-level interactions.” The researchers hope that further research in this and neighboring regions could help to answer these questions.


Source: Max Planck Institute for the Science of Human History [March 19, 2019]



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Azurite | #Geology #GeologyPage #Mineral Locality: Kerrouchene,…


Azurite | #Geology #GeologyPage #Mineral


Locality: Kerrouchene, Khénifra Province, Meknès-Tafilalet Region, Morocco


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Cyanotrichite | #Geology #GeologyPage #Mineral Locality:…


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Fluorite | #Geology #GeologyPage #Mineral Locality: Minerva No…


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Locality: Minerva No 1 Mine, Illinois, United States of America


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Azurite | #Geology #GeologyPage #Mineral Locality: Bou Bekker,…


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Locality: Bou Bekker, Oujda-Angad Province, Morocco


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Fluorite “fluorescent” | #Geology #GeologyPage…


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2019 March 20 Equinox on Planet Earth Image Credit: NASA,…


2019 March 20


Equinox on Planet Earth
Image Credit: NASA, Meteosat, Robert Simmon


Explanation: Welcome to an equinox on planet Earth. Today is the first day of spring in our fair planet’s northern hemisphere, fall in the southern hemisphere, with day and night nearly equal around the globe. At an equinox Earth’s terminator, the dividing line between day and night, connects the planet’s north and south poles as seen at the start of this remarkable time-lapse video compressing an entire year into twelve seconds. To make it, the Meteosat satellite recorded these infrared images every day at the same local time from a geosynchronous orbit. The video actually starts at the September 2010 equinox with the terminator aligned vertically. As the Earth revolves around the Sun, the terminator tilts to provide less daily sunlight to the northern hemisphere, reaching the solstice and northern hemisphere winter at the maximum tilt. As the year continues, the terminator tilts back again and March 2011 equinox arrives halfway through the video. Then the terminator swings past vertical the other way, reaching the the June 2011 solstice and the beginning of northern summer. The video ends as the September equinox returns.


∞ Source: apod.nasa.gov/apod/ap190320.html


An meteor explosion like ten times Hiroshima goes unnoticed


Asteroid Watch logo.


March 19, 2019


A stone 10 meters in diameter shook the Earth in an uninhabited region on December 18. Measuring instruments inherited from the cold war indicate this late.


On December 18, 2018, at 11:48 in the morning, 25.6 kilometers above the Bering Sea, a large space rock streaking straight to Earth at 32 kilometers per second exploded upon entering the atmosphere, consuming itself in a gigantic fireball.



Image above: Some color views of the meteor that flew over the North Pacific in December 2018, taken by Japan’s Himawari satellite.


Below, only the fish may have witnessed the event. But US military satellites have seen the explosion and the Air Force has informed NASA, which has added the event in its database of fireballs since 1988. The phenomenon was described Monday at a Planetary Science Conference in Houston, Texas.


More than 10 times the Hiroshima explosion


The energy released by the explosion is estimated at 173 kilotons by NASA’s Center for Near-Earth Objects. By comparison, the atomic bomb that razed Hiroshima was 15 kt.



Image above: Some color views of the meteor that flew over the North Pacific in December 2018, taken by Japan’s Himawari satellite. The meteor is really clear here – bright orange fireball against the blue + white background!


This is the most powerful explosion in the sky since the 440 kt Chelyabinsk, Russia in 2013 that had 1,500 injured by shattered windows including. A meteor is the luminous phenomenon resulting from the entry into the atmosphere of an asteroid or other celestial body. It’s a shooting star. If everything does not vaporize in the atmosphere and a piece lands, we speak of meteorite.



Animation above: A animation showing the smoke from the Meteor over the Bering Strait last December, produced using data from JMA_kishou’s Himawari satellite. The orange meteor trail in the middle, shadow above-left.


When Simon Proud, meteorologist and satellite data specialist at Oxford University, heard about the meteor by a BBC article on Monday, he had the idea to check the image archive collected by the Japanese weather satellite. Himawari and recorded by his center permanently, he said Tuesday to AFP.



Himawari satellite

Bingo: the satellite was at the right time, in the right place. Simon Proud published the image on Twitter: there is a small fireball above the clouds and the sea.


Ten meters in diameter


Three other civilian satellites, two from NASA (MODIS and VIIRS) and one European (SLSTR), also saw the explosion, according to Proud, but the images are less clear. “It does not surprise me” that such a powerful meteor occurred, soberly reacted Patrick Michel, director of research at the CNRS, the Observatory of the Côte d’Azur, specialist in asteroids.


“It really reminds us that there are lots of things going on above our heads and that it would be good to worry about it,” he said. “It reminds us that even though it is the least likely natural risk for us, it is a risk that exists and over the long term it will eventually materialize,” he continues.



Near Earth Asteroids. Image Credit: ESA

This rock was about ten meters in diameter. The most important threat concerns objects over 150 meters. “Nothing very unusual,” said Rüdiger Jehn, head of the European Space Agency’s (ESA) Global Defense Office. “We were lucky that it was over the ocean.”


“You have to invest a little money to predict these things,” he added. ESA will ask its members for money to create a better protection system at a ministerial meeting in November. “The meteor explosion ensures the perfect promotion of our program, and it’s free,” he said.


Revisiting the passage of the Cheliabisnk meteorite, in Russia, on February 15, 2013, with a power thirty times greater than the energy released by the atomic bomb of Hiroshima.


Related article:


Russia asteroid impact: ESA update and assessment‏
https://orbiterchspacenews.blogspot.com/2013/02/russia-asteroid-impact-esa-update-and.html


Images, Animation, Text, Credits: AFP/JAXA/Himawari satellite/ESA/Günter Space Page/Orbiter.ch Aerospace/Roland Berga.


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ATLAS observes light scattering off light


CERN – ATLAS Experiment logo.


19 March, 2019


The ATLAS Collaboration has reported the observation of light-by-light scattering with a significance beyond eight standard deviations 



Image above: An ATLAS event with energy deposits of two photons in the electromagnetic calorimeter (green) on opposite sides and no other activity in the detector, a clean signature of light-by-light scattering. The Feynman diagram of this process is also shown (Image: CERN).


Light-by-light scattering is a very rare phenomenon in which two photons – particles of light – interact, producing again a pair of photons. This process was among the earliest predictions of quantum electrodynamics (QED), the quantum theory of electromagnetism, and is forbidden in classical physics (such as Maxwell’s theory of electrodynamics).


Direct evidence for light-by-light scattering at high energy had proven elusive for decades, until the Large Hadron Collider (LHC) began its second data-taking period (Run 2). Collisions of lead ions in the LHC provide a uniquely clean environment to study light-by-light scattering. The bunches of lead ions that are accelerated to very high energy are surrounded by an enormous flux of photons. When two lead ions pass close by each other at the centre of the ATLAS detector, but with a distance greater than twice the lead-ion radius, those photons can still interact and scatter off one another without any further interaction between the lead ions, as the reach of the (much stronger) strong force is bound to the radius of a single proton. These interactions are known as ultra-peripheral collisions.


Yesterday, at the Rencontres de Moriond conference (La Thuile, Italy), the ATLAS collaboration reported the observation of light-by-light scattering with a significance of 8.2 standard deviations. The result uses data from the most recent heavy-ion operation of the LHC, which took place in November 2018. This new measurement opens the door to further study the light-by-light scattering process, which is not only interesting in itself as a manifestation of an extremely rare QED phenomenon, but may be sensitive to contributions from particles beyond the Standard Model. It allows for a new generation of searches for hypothetical light and neutral particles.


Read more on the ATLAS website: https://atlas.cern/updates/physics-briefing/atlas-observes-light-scattering-light


Note:


CERN, the European Organization for Nuclear Research, is one of the world’s largest and most respected centres for scientific research. Its business is fundamental physics, finding out what the Universe is made of and how it works. At CERN, the world’s largest and most complex scientific instruments are used to study the basic constituents of matter — the fundamental particles. By studying what happens when these particles collide, physicists learn about the laws of Nature.


The instruments used at CERN are particle accelerators and detectors. Accelerators boost beams of particles to high energies before they are made to collide with each other or with stationary targets. Detectors observe and record the results of these collisions.


Founded in 1954, the CERN Laboratory sits astride the Franco–Swiss border near Geneva. It was one of Europe’s first joint ventures and now has 22 Member States.

Related links:


Large Hadron Collider (LHC): https://home.cern/science/accelerators/large-hadron-collider


ATLAS detector: https://home.cern/science/experiments/atlas


Rencontres de Moriond: http://moriond.in2p3.fr/2019/EW/


Observation of light-by-light scattering: http://cdsweb.cern.ch/record/2667214


For more information about European Organization for Nuclear Research (CERN), Visit: https://home.cern/


Image (mentioned), Text, Credit: European Organization for Nuclear Research (CERN).


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Caption Spotlight (19 March 2019): Everything is (Well)…


Caption Spotlight (19 March 2019): Everything is (Well) Illuminated


The south polar layered deposits are icy layers that have been deposited over millions of years, preserving a climate history of Mars. In this image the layers are well illuminated to accentuate the topography.  


A prior image of this location was acquired with the layered slope facing away from the sun, placing the layers in shadow.  (The top of the cutout image is at a higher elevation.)


NASA/JPL/University of Arizona


NASA Mission Reveals Asteroid Has Big Surprises


NASA – OSIRIS-REx Mission patch.


March 19, 2019



Image above: This view of asteroid Bennu ejecting particles from its surface on January 19 was created by combining two images taken on board NASA’s OSIRIS-REx spacecraft. Other image processing techniques were also applied, such as cropping and adjusting the brightness and contrast of each image. Image Credits: NASA/Goddard/University of Arizona/Lockheed Martin.


A NASA spacecraft that will return a sample of a near-Earth asteroid named Bennu to Earth in 2023 made the first-ever close-up observations of particle plumes erupting from an asteroid’s surface. Bennu also revealed itself to be more rugged than expected, challenging the mission team to alter its flight and sample collection plans, due to the rough terrain.


Bennu is the target of NASA’s Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer (OSIRIS-REx) mission, which began orbiting the asteroid on Dec. 31. Bennu, which is only slightly wider than the height of the Empire State Building, may contain unaltered material from the very beginning of our solar system.


“The discovery of plumes is one of the biggest surprises of my scientific career,” said Dante Lauretta, OSIRIS-REx principal investigator at the University of Arizona, Tucson. “And the rugged terrain went against all of our predictions. Bennu is already surprising us, and our exciting journey there is just getting started.”


Shortly after the discovery of the particle plumes on Jan. 6, the mission science team increased the frequency of observations, and subsequently detected additional particle plumes during the following two months. Although many of the particles were ejected clear of Bennu, the team tracked some particles that orbited Bennu as satellites before returning to the asteroid’s surface.


The OSIRIS-REx team initially spotted the particle plumes in images while the spacecraft was orbiting Bennu at a distance of about one mile (1.61 kilometers). Following a safety assessment, the mission team concluded the particles did not pose a risk to the spacecraft. The team continues to analyze the particle plumes and their possible causes.



Bennu is an active asteroid

Video above: NASA’s OSIRIS-REx mission returned the first scientific observations, revealing that asteroid Bennu is an active active asteroid. OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer) is the first U.S. mission to sample an asteroid (near-Earth asteroid Bennu), retrieve surface material and return it to Earth for study in September 2023. Dante Lauretta, OSIRIS-REx principal investigator, explained the findings in a media teleconference.  Video Credits: NASA/Goddard/University of Arizona/Arizona State University/Lockheed Martin/SciNews.


“The first three months of OSIRIS-REx’s up-close investigation of Bennu have reminded us what discovery is all about — surprises, quick thinking, and flexibility,” said Lori Glaze, acting director of the Planetary Science Division at NASA Headquarters in Washington. “We study asteroids like Bennu to learn about the origin of the solar system. OSIRIS-REx’s sample will help us answer some of the biggest questions about where we come from.”


OSIRIS-REx launched in 2016 to explore Bennu, which is the smallest body ever orbited by spacecraft. Studying Bennu will allow researchers to learn more about the origins of our solar system, the sources of water and organic molecules on Earth, the resources in near-Earth space, as well as improve our understanding of asteroids that could impact Earth.


The OSIRIS-REx team also didn’t anticipate the number and size of boulders on Bennu’s surface. From Earth-based observations, the team expected a generally smooth surface with a few large boulders. Instead, it discovered Bennu’s entire surface is rough and dense with boulders.


The higher-than-expected density of boulders means that the mission’s plans for sample collection, also known as Touch-and-Go (TAG), need to be adjusted. The original mission design was based on a sample site that is hazard-free, with an 82-foot (25-meter) radius. However, because of the unexpectedly rugged terrain, the team hasn’t been able to identify a site of that size on Bennu. Instead, it has begun to identify candidate sites that are much smaller in radius.


The smaller sample site footprint and the greater number of boulders will demand more accurate performance from the spacecraft during its descent to the surface than originally planned. The mission team is developing an updated approach, called Bullseye TAG, to accurately target smaller sample sites.



OSIRS-REx orbiting Bennu

“Throughout OSIRIS-REx’s operations near Bennu, our spacecraft and operations team have demonstrated that we can achieve system performance that beats design requirements,” said Rich Burns, the project manager of OSIRIS-REx at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “Bennu has issued us a challenge to deal with its rugged terrain, and we are confident that OSIRIS-REx is up to the task.”


The original, low-boulder estimate was derived both from Earth-based observations of Bennu’s thermal inertia — or its ability to conduct and store heat — and from radar measurements of its surface roughness. Now that OSIRIS-REx has revealed Bennu’s surface up close, those expectations of a smoother surface have been proven wrong. This suggests the computer models used to interpret previous data do not adequately predict the nature of small, rocky, asteroid surfaces. The team is revising these models with the data from Bennu.


The OSIRIS-REx science team has made many other discoveries about Bennu in the three months since the spacecraft arrived at the asteroid, some of which were presented Tuesday at the 50th Lunar and Planetary Conference in Houston and in a special collection of papers issued by the journal Nature.


The team has directly observed a change in the spin rate of Bennu as a result of what is known as the Yarkovsky-O’Keefe-Radzievskii-Paddack (YORP) effect. The uneven heating and cooling of Bennu as it rotates in sunlight is causing the asteroid to increase its rotation speed. As a result, Bennu’s rotation period is decreasing by about one second every 100 years. Separately, two of the spacecraft’s instruments, the MapCam color imager and the OSIRIS-REx Thermal Emission Spectrometer (OTES), have made detections of magnetite on Bennu’s surface, which bolsters earlier findings indicating the interaction of rock with liquid water on Bennu’s parent body.


Goddard provides overall mission management, systems engineering, and the safety and mission assurance for OSIRIS-REx. Dante Lauretta of the University of Arizona, Tucson, is the principal investigator, and the University of Arizona also leads the science team and the mission’s science observation planning and data processing. Lockheed Martin Space in Denver built the spacecraft and is providing flight operations. Goddard and KinetX Aerospace are responsible for navigating the OSIRIS-REx spacecraft. OSIRIS-REx is the third mission in NASA’s New Frontiers Program, which is managed by NASA’s Marshall Space Flight Center in Huntsville, Alabama, for the agency’s Science Mission Directorate in Washington.


To find out more about the OSIRIS-REx mission, visit: https://www.nasa.gov/osiris-rex


Image, Animation, Text, Credits: NASA/Dwayne Brown/JoAnna Wendel/Sean Potter/GSFC/Nancy Neal Jones/University of Arizona/Erin Morton.


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NASA’s Fermi Satellite Clocks ‘Cannonball’ Pulsar Speeding Through Space


NASA – Fermi Gamma-ray Space Telescope logo.


March 19, 2019


Astronomers found a pulsar hurtling through space at nearly 2.5 million miles an hour — so fast it could travel the distance between Earth and the Moon in just 6 minutes. The discovery was made using NASA’s Fermi Gamma-ray Space Telescope and the National Science Foundation’s Karl G. Jansky Very Large Array (VLA).


Pulsars are superdense, rapidly spinning neutron stars left behind when a massive star explodes. This one, dubbed PSR J0002+6216 (J0002 for short), sports a radio-emitting tail pointing directly toward the expanding debris of a recent supernova explosion.


“Thanks to its narrow dart-like tail and a fortuitous viewing angle, we can trace this pulsar straight back to its birthplace,” said Frank Schinzel, a scientist at the National Radio Astronomy Observatory (NRAO) in Socorro, New Mexico. “Further study of this object will help us better understand how these explosions are able to ‘kick’ neutron stars to such high speed.”



NASA’s Fermi Satellite Clocks a “Cannonball” Pulsar

Video above: New radio observations combined with 10 years of data from NASA’s Fermi Gamma-ray Space Telescope have revealed a runaway pulsar that escaped the blast wave of the supernova that formed it. Image Credits: NASA’s Goddard Space Flight Center.


Schinzel, together with his colleagues Matthew Kerr at the U.S. Naval Research Laboratory in Washington, and NRAO scientists Dale Frail, Urvashi Rau and Sanjay Bhatnagar presented the discovery at the High Energy Astrophysics Division meeting of the American Astronomical Society in Monterey, California. A paper describing the team’s results has been submitted for publication in a future edition of The Astrophysical Journal Letters.


Pulsar J0002 was discovered in 2017 by a citizen-science project called Einstein@Home, which uses time on the computers of volunteers to process Fermi gamma-ray data. Thanks to computer processing time collectively exceeding 10,000 years, the project has identified 23 gamma-ray pulsars to date.

Located about 6,500 light-years away in the constellation Cassiopeia, J0002 spins 8.7 times a second, producing a pulse of gamma rays with each rotation.


The pulsar lies about 53 light-years from the center of a supernova remnant called CTB 1. Its rapid motion through interstellar gas results in shock waves that produce the tail of magnetic energy and accelerated particles detected at radio wavelengths using the VLA. The tail extends 13 light-years and clearly points back to the center of CTB 1.



Image above: CTB 1, seen here in a deep exposure that highlights visible light from hydrogen gas, is the expanding wreckage of a massive star that exploded some 10,000 years ago. The pulsar formed in the center of the collapsing star is moving so fast it has completely exited the faint shell. Image Credit: Scott Rosen.


Using Fermi data and a technique called pulsar timing, the team was able to measure how quickly and in what direction the pulsar is moving across our line of sight.


“The longer the data set, the more powerful the pulsar timing technique is,” said Kerr. “Fermi’s lovely 10-year data set is essentially what made this measurement possible.”


The result supports the idea that the pulsar was kicked into high speed by the supernova responsible for CTB 1, which occurred about 10,000 years ago.


J0002 is speeding through space five times faster than the average pulsar, and faster than 99 percent of those with measured speeds. It will eventually escape our galaxy.


At first, the supernova’s expanding debris would have moved outward faster than J0002, but over thousands of years the shell’s interaction with interstellar gas produced a drag that gradually slowed this motion. Meanwhile, the pulsar, behaving more like a cannonball, steadily raced through the remnant, escaping it about 5,000 years after the explosion.



Image above: The CTB 1 supernova remnant resembles a ghostly bubble in this image, which combines new 1.5 gigahertz observations from the Very Large Array (VLA) radio telescope (orange, near center) with older observations from the Dominion Radio Astrophysical Observatory’s Canadian Galactic Plane Survey (1.42 gigahertz, magenta and yellow; 408 megahertz, green) and infrared data (blue). The VLA data clearly reveal the straight, glowing trail from pulsar J0002+6216 and the curved rim of the remnant’s shell. CTB 1 is about half a degree across, the apparent size of a full Moon. Image Credits: Composite by Jayanne English, University of Manitoba, using data from NRAO/F. Schinzel et al., DRAO/Canadian Galactic Plane Survey and NASA/IRAS.


Exactly how the pulsar was accelerated to such high speed during the supernova explosion remains unclear, and further study of J0002 will help shed light on the process. One possible mechanism involves instabilities in the collapsing star forming a region of dense, slow-moving matter that survives long enough to serve as a “gravitational tugboat,” accelerating the nascent neutron star toward it.


The team plans additional observations using the VLA, the National Science Foundation’s Very Long Baseline Array (VLBA) and NASA’s Chandra X-ray Observatory.


The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.


The Fermi Gamma-ray Space Telescope is an astrophysics and particle physics partnership managed by NASA’s Goddard Space Flight Center in Greenbelt, Maryland. Fermi was developed in collaboration with the U.S. Department of Energy, with important contributions from academic institutions and partners in France, Germany, Italy, Japan, Sweden and the United States.


Related links:


Karl G. Jansky Very Large Array (VLA): https://science.nrao.edu/facilities/vla


Very Long Baseline Array (VLBA): https://public.nrao.edu/telescopes/vlba/


NASA’s Chandra X-ray Observatory: http://chandra.harvard.edu/


Fermi Gamma-Ray Space Telescope: http://www.nasa.gov/mission_pages/GLAST/main/index.html


Images (mentioned), Video (mentioned), Text, Credits: NASA/Rob Garner/Goddard Space Flight Center, by Francis Reddy.


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Human Research and Spacewalk Computer Training on Orbital Lab


ISS – Expedition 59 Mission patch.


March 19, 2019


The Expedition 59 crew continued gearing up for Friday’s spacewalk amid a variety of human research activities today. Meanwhile, the three newest International Space Station crewmembers found time to get up to speed on lab systems and life in space.


Friday’s spacewalkers will be NASA astronauts Anne McClain and Nick Hague. The duo started the day getting tools ready and using 3-D computer software to review spacewalk procedures and robotics maneuvers. Flight Engineers David Saint-Jacques and Christina Koch joined McClain and Hague at the end of the day for an hour-long conference with spacewalk experts in Mission Control.



Image above: NASA astronauts Nick Hague, Anne McClain and Christina Koch (right) work on U.S. spacesuit maintenance in the Quest airlock of the International Space Station. Image Credit: NASA.


The spacewalkers will work for about six hours on the Port-4 truss structure swapping batteries and installing adapter plates. Friday’s spacewalk to upgrade the station’s power storage capacity begins at 8:05 a.m. EDT. NASA TV’s live spacewalk coverage begins at 6:30 a.m.


Life science continued full-speed ahead today despite the spacewalk preparations and a new crew getting used to microgravity. Hague, Koch and Saint-Jacques drew their blood samples throughout Tuesday and stowed them in science freezers for later analysis.



Image above: Sunrise over Gulf of Bengal, Suyuz MS-12 illuminated on the dark sky, seen by EarthCam on ISS, speed: 27’612 Km/h, altitude: 406,68 Km, image captured by Roland Berga (on Earth in Switzerland) from International Space Station (ISS) using ISS-HD Live application with EarthCam’s from ISS on March 19, 2019 at 23:08 UTC. Image Credits: Orbiter.ch Aerospace/Roland Berga.


Koch also spent a couple of hours in the Columbus lab module on the Vection study exploring how microgravity affects her perception. Saint-Jacques prepared Marrow experiment gear for return on an upcoming SpaceX Dragon cargo mission.


Flight Engineers Alexey Ovchinin, Hague and Koch spent each about an hour familiarizing themselves with station facilities today. The new trio will orbit Earth for at least six-and-a-half months.


Related links:


Expedition 59: https://www.nasa.gov/mission_pages/station/expeditions/expedition59/index.html


Port-4 truss structure: https://www.nasa.gov/mission_pages/station/structure/elements/truss-structure


Life science: https://www.nasa.gov/mission_pages/station/research/index.html


Columbus lab module: https://www.nasa.gov/mission_pages/station/structure/elements/europe-columbus-laboratory


Vection: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7484


Marrow: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=1673


Space Station Research and Technology: https://www.nasa.gov/mission_pages/station/research/index.html


International Space Station (ISS): https://www.nasa.gov/mission_pages/station/main/index.html


Images (mentioned), Text, Credits: NASA/Mark Garcia/Orbiter.ch Aerospace/Roland Berga.


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Babylonian treasure seized at UK airport

An attempt to smuggle a Babylonian treasure into Britain has been foiled after it was seized at Britain’s Heathrow airport.











Babylonian treasure seized at UK airport
The kudurru was an official document drawn up on the instructions of the Babylonian king to record the gift
of lands or other benefits bestowed on a particular individual [Credit: British Museum]

The inscribed cuneiform stone antiquity, which is about 30cm high, had been looted from Iraq. Dating from the second millennium BC, it is worthy of the world’s greatest museums and valued at hundreds of thousands of pounds.


A Border Force officer’s suspicions were raised by a declaration that the cargo contained a “carved stone for home decoration” made in Turkey and valued at “300” in an unspecified currency.


After Googling the object, the officer contacted the British Museum, having discovered that its collection boasted one of the few surviving examples of a Babylonian kudurru, an official document drawn up on the instructions of the Babylonian king to record the gift of lands or other benefits bestowed on particular individuals. Later this month the British Museum will stage the object’s official handover to Iraq.


Dr St John Simpson, a senior curator at the British Museum, told the Guardian: “It’s a museum-quality piece. Even though it’s broken, it should be on display in a museum.


“Declaring it as ‘carved stone for home decoration’ was being economical with the truth, as they say. A decorative ornament for a rather hefty mantelpiece. It is a very heavy object.”


It dates from the reign of the Babylonian king Nebuchadnezzar I (about 1126-1103BC), not to be confused with his famous later namesake Nebuchadnezzar II (605-562BC).


This ruler is practically unknown beyond his victory over the kingdom of Elam in present-day Iran, when he recovered the cultic idol of the Babylonian state god, Marduk. The kudurru’s inscription refers to a military campaign, perhaps that very one.











Babylonian treasure seized at UK airport
The stone dates from the reign of King Nebuchadnezzar I (about 1126-1103BC)
[Credit: British Museum]

Simpson said: “It’s a historical document, a primary document for a little-known episode of Mesopotamian history, showing the relationship – not always friendly – between neighbours.”


The cuneiform stone contains two columns of text written in the Babylonian language. They are difficult to interpret as the object is broken and its central portion is worn away. It must originally have been placed in a temple, as its concluding lines contain curse formulae to safeguard the monument.


Simpson said: “Importantly, this kudurru has been neither previously recorded nor published and must therefore come from illicit digging at a site in southern Iraq. The text mentions the god Enlil and the goddess Gula and refers several times to the city of Nippur, in southern Iraq, where Enlil was the chief god. This makes it quite likely that this kudurru originates from Nippur or its close vicinity.”


He noted that many archaeological sites in southern Iraq were badly looted between 1994 and 2004, during which time he suspects this kudurru was removed. The whereabouts of its lower half are unknown. “Hopefully, it is still in the ground somewhere in Iraq and may one day be found by archaeologists.”


The object has been declared crown property after the British importer failed to demonstrate legal title. Investigations are continuing.


On 19 March the British Museum will formally hand it over to the Iraqi embassy in London, to be transferred to the Iraq Museum in Baghdad, which is now fully restored and open to visitors.


Asked whether looting was still occurring in Iraq, Simpson said: “The situation in Iraq is actually good now. They have a system of archaeological police who are armed, who patrol and who are responsible for the protection of all sites that are currently being excavated. They also patrol the unexcavated ones.”


Author: Dalya Alberge | Source: The Guardian [March 13, 2019]



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Amsterdam’s Rijksmuseum to start talks about stolen art with Sri Lanka

The Rijkmuseum in Amsterdam is starting talks with Sri Lanka and Indonesia about some 1,000 pieces in its collection that may have been stolen and become part of the Dutch ‘colonial heritage’, local news sources reports.











Amsterdam's Rijksmuseum to start talks about stolen art with Sri Lanka
The cannon of the king of Kandy, which seized the Netherlands in 1765 during a military campaign
[Credit: © Rijksmuseum]

The move comes after last week’s decision by the Dutch National Museum of World Cultures (NMWC) to publish guidelines for countries to claim stolen art or art that is of great cultural significance to a country.
‘It’s a disgrace that the Netherlands is only now turning its attention to the return of the colonial heritage’, Rijksmuseum director Taco Dibbets told Trouw.


‘We should have done it earlier and there is no excuse.’ Talks in Sri Lanka will begin in two weeks’ time and will centre around the return of some ten objects.











Amsterdam's Rijksmuseum to start talks about stolen art with Sri Lanka
Banjarmasin diamond, once the property of Banjarmasin sultan Panembahan Adam
[Credit: © Rijksmuseum]

They include a ruby-encrusted canon which was taken as booty following a military campaign in 1765 and the Banjarmasin diamond which was the property of sultan Panembahan Adam of Banjarmasin (South Borneo) which was colonised by the Dutch in 1856.


The Rijksmuseum has around 4,000 colonial object, not all of which, Dibbits says, were stolen. All objects are owned by the state so museums cannot take the decision to return an object on their own.


The NMWC guidelines have come in for criticism because they don’t include much about the steps museums themselves could take before claims come in.


‘Before there is any negotiating to be done, the Netherlands already sets out its conditions. It’s a typically Dutch approach. How is that going to lead to a satisfactory joint decision?, Trouw quotes historian and stolen colonial art expert Jos van Beurden as saying.


Source: Dutch News [March 13, 2019]



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