среда, 3 октября 2018 г.

JAXA – Success! MASCOT landed safely on asteroid Ryugu


JAXA – Hayabusa2 Mission patch.


October 3, 2018


A shoebox-sized lander called the Mobile Asteroid Surface Scout (MASCOT) deployed from its mothership, Japan’s Hayabusa2 spacecraft, as planned at 9:57 p.m. EDT Tuesday (Oct. 2; 0157 GMT on Oct. 3) and came to rest on Ryugu shortly thereafter.


“It could not have gone better,” MASCOT project manager Tra-Mi Ho, from the DLR Institute of Space Systems in Bremen, Germany, said in a statement. (DLR is the German acronym for the German Aerospace Center, which built MASCOT in collaboration with the French space agency, CNES.



Image above: Japan’s Hayabusa2 spacecraft successfully dropped the MASCOT lander on the asteroid Ryugu on Oct. 3, 2018 (Japan Standard Time). Left: Illustration of the MASCOT lander separating from the Hayabusa2 mother ship. Right: Illustration of MASCOT landing on the surface of the asteroid Ryugu. Image Credit: JAXA.


“From the lander’s telemetry, we were able to see that it separated from the mothercraft and made contact with the asteroid surface approximately 20 minutes later,” Ho added.


MASCOT has already started gathering data with its four onboard science instruments — a camera, a radiometer, a spectrometer and a magnetometer — mission team members said. The 22-lb. (10 kilograms) lander must make haste, because its battery is expected to die just 16 hours after touchdown.



Flight model of MASCOT. Image credit: DLR

MASCOT took 20 photos during its slow descent toward Ryugu, and these images are stored aboard Hayabusa2 at the moment, mission team members said. And observations made by the magnetometer before separation (which occurred when Hayabusa2 was about 167 feet, or 51 meters, above Ryugu) have already made it down to Earth.


“The measurements show the relatively weak field of the solar wind and the very strong magnetic disturbances caused by the spacecraft,” MASCOT team member Karl-Heinz Glaßmeier, from the Technical University of Braunschweig in Germany, said in the same statement. “At the moment of the separation, we expected a clear decrease of the interference field — and we were able to recognize this clearly.”



Image above: The MASCOT landing site candidate region (light blue area) on the asteroid Ryugu. Since MASCOT was expected to bounce several times after first touching down, a reasonably wide region was selected. Image Credit: AXA, University of Tokyo, Kochi University, Rikkyo University, Nagoya University, Chiba Institute of Technology, Meiji University, University of Aizu, AIST, CNES, DLR.


MASCOT is following in the footsteps of MINERVA-II1A and MINERVA-II1B, two 2.4-lb. (1.1 kg) rovers that deployed from Hayabusa2 on the night of Sept. 21. Both of those little robots aced their touchdowns and soon began exploring the surface of Ryugu.


Like the Japanese-built MINERVA-II1A and MINERVA-II1B, the autonomous MASCOT can move by hopping, which it does by manipulating a metallic “swing arm” inside its body. The lander can also use this arm to right itself on Ryugu’s surface — an important feature, because MASCOT needs to be right side up to gather data and beam it up to Hayabusa2.


The $150 million Hayabusa2 mission launched in December 2014 and arrived in orbit around Ryugu in late June of this year. The mothership may have one more rover deployment to go: It still carries the “optional” hopper MINERVA-II2, which could make its way to Ryugu’s surface next year.



Image above: Illustration of the Hayabusa2 spacecraft. MASCOT is stored on the -Y-plane (left side) panel. Image credit: JAXA.


And the orbiter itself will make its way down to the space rock in 2019 as well, after sending a nonexplosive impactor barreling into Ryugu. Hayabusa2 will grab pristine, previously subsurface samples from the newly created crater; this material is scheduled to come down to Earth in a return capsule in December 2020.


Data gathered by the mission at Ryugu and by scientists who examine its returned sample should shed considerable light on the solar system’s early history and the role that carbon-rich asteroids like Ryugu may have played in life’s emergence on Earth, Hayabusa2 team members have said.


Related article:


Hayabusa2 Touches Down Ryugu:
http://orbiterchspacenews.blogspot.com/2018/09/hayabusa2-touches-down-ryugu.html


Related links:


JAXA’s Hayabusa2 website: http://www.hayabusa2.jaxa.jp/en/


MASCOT website at DLR: https://www.dlr.de/dlr/en/desktopdefault.aspx/tabid-10975/


MASCOT website at CNES: https://mascot.cnes.fr/en/MASCOT/index.htm


Images (mentioned), Text, Credits: JAXA/Space.com/Mike Wall.


Best regards, Orbiter.chArchive link


New approach offers high-resolution seismic monitoring of the…


New approach offers high-resolution seismic monitoring of the shallow subsurface http://www.geologypage.com/2018/10/new-approach-offers-high-resolution-seismic-monitoring-of-the-shallow-subsurface.html


130-year-old brain coral reveals encouraging news for open ocean…


130-year-old brain coral reveals encouraging news for open ocean http://www.geologypage.com/2018/10/130-year-old-brain-coral-reveals-encouraging-news-for-open-ocean.html


Scientists propose that vibrios have significant roles in marine…


Scientists propose that vibrios have significant roles in marine organic carbon cycle http://www.geologypage.com/2018/10/scientists-propose-that-vibrios-have-significant-roles-in-marine-organic-carbon-cycle.html


Kaikoura earthquake research suggests new approach to earthquake…


Kaikoura earthquake research suggests new approach to earthquake forecasting http://www.geologypage.com/2018/10/kaikoura-earthquake-research-suggests-new-approach-to-earthquake-forecasting.html


A wrench in Earth’s engine: Stagnant slabs…


A wrench in Earth’s engine: Stagnant slabs http://www.geologypage.com/2018/10/a-wrench-in-earths-engine-stagnant-slabs.html


Brain Draining These bright blue tubes are the brain’s…


Brain Draining


These bright blue tubes are the brain’s drainage system: blood-carrying arteries known as subarachnoid vessels, lying on the spongy brown surface of the brain. Captured with a powerful super-resolution scanning electron microscope and coloured using computer software, the vital vessels are not only responsible for supplying oxygen and nutrients to hungry brain cells, but also taking away toxic waste products. Although these particular vessels are perfectly healthy, researchers are interested in finding out what happens when they don’t work properly. Unless they’re regularly washed away, harmful molecules can build up in the arteries and smaller blood vessels and cause a condition known as cerebral amyloid angiopathy (CAA) – a key feature of the incurable neurodegenerative disease vascular dementia. By zooming in on the brain’s drains, researchers are hoping to find out how they may be involved in the development of dementia, which could lead to new ideas for treatment or prevention.


Written by Kat Arney



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Dormant genes brought to life in new generations

The genetic differences in phyloplankton living in close geographic proximity can be great, something which long has surprised researchers. Now new research shows that the ability of phyloplankton to generate resting stages can be an important part of the explanation.











Dormant genes brought to life in new generations
Credit: University of Gothenburg

Phyloplankton have ample opportunity for broad dispersal since they are small, numerous and carried by the current. For this reason, researchers have earlier thought that phyloplankton are genetically alike across large areas. Instead, it has been discovered that the genetic differences can in many cases be great among neighboring populations.
A new study by researchers from the University of Gothenburg, identifies phyloplankton’s ability to generate resting stages as an important explanation for genetic differences.


“When a species forms cysts, it enters a resting stage, similar in function to the seeds produced by plants, through which the species can survive over a long period. Some species can survive as long as a century,” says Lisa Sundqvist, who has done her research at the University of Gothenburg.


Old genes preserved in repositories at the bottom of the ocean


When cysts are formed, they fall to the bottom where they accumulate in the sediment and form repositories of prior generations. “The repository serves as a gene bank that the cysts can hatch from and begin to live again in the water,” says Lisa Sundqvist.


With the help of a model the researchers show that a population can establish itself in a location when the species is able to generate resting stages. This process means that genetic differences can be preserved and become stronger over time, even if there is a displacement of individuals between to different areas.


“Cysts found in the sediment provide a local supply of genes from earlier generations that can outcompete or reduce the influence of the gene supply from current populations in other areas. A review of the literature also shows that genetic difference between nearby populations are far more common among the phyloplankton that can generate enduring resting stages when compared with those that cannot. This supports our theory significantly,” says Lisa Sundqvist.


More significant effect than expected


The new study shows that the anchoring effect of resting stages is likely far more important than researchers have previously thought. It can be a significant part of the explanation for the differences in genetic makeup that researchers see in species that generate resting stages compared with those that don’t.


‘This has great significance for the capacity to adapt to the environment,” says Lisa Sundqvist.


Source: University of Gothenburg [October 01, 2018]



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A wrench in Earth’s engine

Researchers at CU Boulder report that they may have solved a geophysical mystery, pinning down the likely cause of a phenomenon that resembles a wrench in the engine of the planet.











A wrench in Earth's engine
Earth’s mantle (dark red) lies below the crust (brown layer near the surface) and above
the outer core (bright red) [Credit: Argonne National Laboratory/Flickr]

In a study published in Nature Geoscience, the team explored the physics of “stagnant slabs.” These geophysical oddities form when huge chunks of Earth’s oceanic plates are forced deep underground at the edges of certain continental plates. The chunks sink down into the planet’s interior for hundreds of miles until they suddenly–and for reasons scientists can’t explain–stop like a stalled car.
CU Boulder’s Wei Mao and Shijie Zhong, however, may have found the reason for that halt. Using computer simulations, the researchers examined a series of stagnant slabs in the Pacific Ocean near Japan and the Philippines. They discovered that these cold rocks seem to be sliding on a thin layer of weak material lying at the boundary of the planet’s upper and lower mantle–roughly 660 kilometers, or 410 miles, below the surface.
And the stoppage is likely temporary: “Although we see these slabs stagnate, they are a fairly recent phenomena, probably happening in the last 20 million years,” said Zhong, a co-author of the new study and a professor in CU Boulder’s Department of Physics.


The findings matter for tectonics and volcanism on the Earth’s surface. Zhong explained that the planet’s mantle, which lies above the core, generates vast amounts of heat. To cool the globe down, hotter rocks rise up through the mantle and colder rocks sink.


“You can think of this mantle convection as a big engine that drives all of what we see on Earth’s surface: earthquakes, mountain building, plate tectonics, volcanos and even Earth’s magnetic field,” Zhong said.











A wrench in Earth's engine
Graphic of stagnant slabs under the Japanese island of Honshu (top) and the Mariana Trench (bottom) using seismic
data (left) and computer simulations (right). Stagnant slabs (blue) plunge down to the border between the upper
and lower mantle then screech to a stop [Credit: Mao & Zhong, Nature Geoscience ,2018]

The existence of stagnant slabs, which geophysicists first located about a decade ago, however, complicates that metaphor, suggesting that Earth’s engine may grind to a halt in some areas. That, in turn, may change how scientists think diverse features, such as East Asia’s roiling volcanos, form over geologic time.


Scientists have mostly located such slabs in the western Pacific Ocean, specifically off the east coast of Japan and deep below the Mariana Trench. They occur at the sites of subduction zones, or areas where oceanic plates at the surface of the planet plunge hundreds of miles below ground.


Slabs seen at similar sites near North and South America behave in ways that geophysicists might expect: They dive through Earth’s upper mantle and into the lower mantle where they heat up near the core.


But around Asia, “they simply don’t go down,” Zhong said. Instead, the slabs spread out horizontally near the boundary between the upper and lower mantle, a point at which heat and pressure inside Earth cause minerals to change from one phase to another.


To find out why slabs go stagnant, Zhong and Mao, a graduate student in physics, developed realistic simulations of how energy and rock cycle around the entire planet.


They found that the only way they could explain the behavior of the stagnant slabs was if a thin layer of less-viscous rock was wedged in between the two halves of the mantle. While no one has directly observed such a layer, researchers have predicted that it exists by studying the effects of heat and pressure on rock.


If it does, such a layer would act like a greasy puddle in the middle of the planet. “If you introduce a weak layer at that depth, somehow the reduced viscosity helps lubricate the region,” Zhong said. “The slabs get deflected and can keep going for a long distance horizontally.”


Stagnant slabs seem to occur off the coast of Asia, but not the Americas, because the movement of the continents above gives those chunks of rock more room to slide. Zhong, however, said that he doesn’t think the slabs will stay stuck. With enough time, he suspects that they will break through the slick part of the mantle and continue their plunge toward the planet’s core.


The planet, in other words, would still behave like an engine–just with a few sticky spots. “New research suggests that the story may be more complicated than we previously thought,” Zhong said.


Author: Daniel Strai | Source: University of Colorado at Boulder [October 1, 2018]



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Where did broadleaved evergreen trees survive during the last glacial period in Japan?

Japanese researchers investigated whether a dominant tree of warm temperate broadleaved forests in Japan, Castanopsis sieboldii, underwent northward migration over hundreds of kilometres from Last Glacial Maximum (LGM) (about 21,000 years ago) refugia in the Ryukyu archipelago and southern Kyushu, where fossil pollen indicates the LGM survival of broadleaved evergreen forests, or was in fact able to survive closer to its present range in colder areas such as the coast of the Japan Sea and the Pacific Ocean side of eastern Honshu during the Last Glacial Maximum (LGM). Using a combined genetic analysis and modelling approach, it was found that the East Japan populations, where few pollen fossil records exist, survived in situ during the LGM on both the Japan Sea and Pacific coasts and were not established via expansion after the LGM from southern areas. Their findings were published online in Heredity.











Where did broadleaved evergreen trees survive during the last glacial period in Japan?
Area with darker color indicates higher probability of suitable habitat. In the Last Glacial Maximum (LGM), the sea level
 decreased by about 120 m compared to the present, and the land was expanded. The dashed line shows the estimated
coastline at the LGM. The areas surrounded by a red line are estimated areas (West Japan, Japan Sea, and East Japan),
 where C. sieboldii is likely to have survived during LGM based on genetic and modelling based evidence (the Ryukyu
archipelago is not shown in the figure) [Credit: ©2018 Forestry and Forest Products Research Institute,
Osaka University, and Gifu Academy of Forest Science and Culture]

The climate of the earth about 21,000 to 18,000 years ago during the LGM was particularly cold, with average temperatures 5 to 7  lower than the present-day. From the excavation of fossil pollen and plant bodies, it is believed that broadleaved evergreen forests were driven to warmer areas in the Ryukyu Archipelago and southern Kyushu during the LGM. After the LGM, they expanded their distribution northward to the Japan Sea and the Pacific coast. There has been a debate on whether the broadleaved evergreen forests, which presently occupy wide areas in warm temperate regions of Japan, had expanded from a limited area in the southern part of Kyushu, or survived in small forests in various areas in Japan. Using a species distribution modelling approach to model the species’ LGM distribution, a suitable climate is predicted in the southern part of the Pacific coast, which is further supported by genetic evidence.
In the study, researchers investigated where C. sieboldii, a dominant tree species of broadleaved evergreen forests in Japan, inhabited during the glacial period by constructing multiple models based on genetic diversity. The result indicated that the Ryukyu and the West Group existed from the oldest period, and that the East and the Japan Sea Group were formed from the West Group. Furthermore, the estimated time of diversification suggested that these four groups had already been established before the LGM. The result suggested that C. sieboldii survived separately in Ryukyu, West, Japan Sea, East during the LGM, and expanded the population as it became warmer during the past-glacial.











Where did broadleaved evergreen trees survive during the last glacial period in Japan?
In this model, after the Ryukyu (R) and the West (W) Group diverged, the Japan Sea (J) and the East (E) Group diverged
 from the West (W) Group. West and East Group includes populations in western and eastern parts of the main islands
along the Pacific Coast, respectively. The branch length is proportional to the number of generations, with the major
splits in the species estimated to have occurred 118,400 and 43,100 years ago, assuming that one generation
of C. sieboldii is 100 years [Credit: ©2018 Forestry and Forest Products Research Institute,
Osaka University, and Gifu Academy of Forest Science and Culture]

This study identified major genetic lineages in the broadleaved evergreen tree species C. sieboldii in the Ryukyu Archipelago, Western Japan, the Japan Sea, and Eastern Japan. The unique genetic composition of each region has formed as a result of a long history of genetic isolation associated with the glacial-interglacial cycles.
In recent years, the importance of preserving local genetic diversity has been recognized. When planting broadleaved trees to assist natural regeneration or during afforestation, it is necessary not to disturb the local genetic diversity as much as possible.


Lead author Kyoko Aoki at Osaka University says, “Our research highlights the importance of restricting the distribution of seedlings across the genetic boundaries identified between Ryukyu, Western Japan, Japan Sea, and Eastern Japan in order to retain genetic patterns which have formed over thousands of years.”


Source: Osaka University [October 01, 2018]



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Traces of opiates found in ancient Cypriot vessel

Researchers at the University of York and the British Museum have discovered traces of opiates preserved inside a distinctive vessel dating back to the Late Bronze Age.











Traces of opiates found in ancient Cypriot vessel
The base-ring juglet resembles the seed head of an opium poppy
[Credit: British Museum]

Vessels of this type, known as ‘base-ring juglets’, have long been thought to have links with opium use because when inverted they resemble the seed head of the opium poppy; they are known to have been widely traded in the eastern Mediterranean ca. 1650 – 1350BC.


Researchers used a range of analytical techniques to study a particular juglet housed in the British Museum, which is a sealed vessel, allowing the contents inside to be preserved. This meant that there was a rare opportunity for scientists to investigate what components might have survived.


Initial analysis by scientists at the British Museum showed that the juglet residue was mostly composed of a plant oil but hinted at the presence of opium alkaloids, a group of organic compounds derived from the opium poppy, and that are known to have significant psychological effects on the human body.


To conclusively detect the alkaloids and demonstrate the presence of opiates in the oil-based residue of the vessel, however, a new analytical technique was needed.


Using instruments in the Centre of Excellence in Mass Spectrometry at the University of York, Dr Rachel Smith developed the new analytical method as part of her PhD at the University’s Department of Chemistry.


Dr Smith said: “The particular opiate alkaloids we detected are ones we have shown to be the most resistant to degradation, which makes them better targets in ancient residues than more well-known opiates such as morphine.


“We found the alkaloids in degraded plant oil, so the question as to how opium would have been used in this juglet still remains. Could it have been one ingredient amongst others in an oil-based mixture, or could the juglet have been re-used for oil after the opium or something else entirely?”


In the past, it has been argued that these juglets could have been used to hold poppy seed oil, containing traces of opium, used for anointing or in a perfume. In this theory, the opium effects may have held symbolic significance.


Professor Jane Thomas-Oates, Chair of Analytical Science in the Department of Chemistry, and supervisor of the study at the University of York, said: “The juglet is significant in revealing important details about trade and the culture of the period, so it was important to us to try and progress the debate about what it might have been used for.


“We were able to establish a rigorous method for detecting opiates in this kind of residue, but the next analytical challenge is to see if we can succeed with less well-preserved residues.”


This is the first time that reliable chemical evidence has been produced to link the opium poppy with a base-ring juglet, despite many previous attempts by researchers over the years.


Dr Rebecca Stacey, Senior Scientist in the Department of Scientific Research at the British Museum, said: “It is important to remember that this is just one vessel, so the result raises lots of questions about the contents of the juglet and its purpose. The presence of the alkaloids here is unequivocal and lends a new perspective to the debate about their significance.”


The research is published in the Royal Society of Chemistry’s journal Analyst.


Source: University of York [October 02, 2018]



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‘Jewel of Roman Empire’ faces Libya dangers

Perched on the edge of Libya’s Mediterranean coast, the ancient city of Sabratha remains an awe-inspiring spectacle, the pink columns of its amphitheatre towering above turquoise waters.











'Jewel of Roman Empire' faces Libya dangers
A picture taken on September 1, 2018 shows colomns at the site of the ancient Roman city of Sabratha, around 70 kilometres
 from the Libyan capital Tripoli. The United Nations Educational, Scientific and Cultural Organization (UNESCO)
declared Sabratha to be at risk in July 2016, along with four other Libyan sites on its World Heritage list
[Credit: Mahmud TurkiaAFP]

But the world heritage site is classed as “endangered” by UNESCO, its majestic structures pockmarked by mortar and small arms fire.


Shell casings and bullets still litter the surrounding earth, a year after clashes between rival armed groups.


Locals say snipers positioned themselves at the top of the amphitheatre, once a jewel of the Roman Empire.











'Jewel of Roman Empire' faces Libya dangers
A picture taken on September 1, 2018 shows an edifice at the site of the ancient Roman city of Sabratha, around
70 kilometres from the Libyan capital Tripoli. The United Nations Educational, Scientific and Cultural
Organization (UNESCO) declared Sabratha to be at risk in July 2016, along with four
other Libyan sites on its World Heritage list [Credit: Mahmud TurkiaAFP]

Bringing bloodshed back to the gladiatorial arena some 18 centuries after it was built, 39 people were killed and 300 wounded in the fighting.
Today, the site around 70 kilometres (45 miles) from the capital lies eerily abandoned, encircled by parched grass and weeds.


Since the toppling and killing of Libya’s dictator Moamer Kadhafi in a 2011 uprising, Sabratha has become a key departure point for illegal migration.











'Jewel of Roman Empire' faces Libya dangers
A picture taken on September 1, 2018 shows a portion of the site of the ancient Roman city of Sabratha, around
70 kilometres from the Libyan capital Tripoli. The United Nations Educational, Scientific and Cultural
Organization (UNESCO) declared Sabratha to be at risk in July 2016, along with four
other Libyan sites on its World Heritage list [Credit: Mahmud TurkiaAFP]

Smugglers and militias have profited amply from a chronic security vacuum.


It is from the long and deserted shores a few kilometres (miles) from ancient Sabratha that most migrants start their perilous boat journeys towards Europe.


‘Permanent danger’


UNESCO declared Sabratha to be at risk in July 2016, along with four other Libyan sites on its World Heritage list.











'Jewel of Roman Empire' faces Libya dangers
A picture shows a detail from a high relief at the site of the ancient Roman city of Sabratha, around 70 kilometres
from the Libyan capital Tripoli. The United Nations Educational, Scientific and Cultural Organization (UNESCO)
declared Sabratha to be at risk in July 2016, along with four other Libyan sites on its World Heritage list
[Credit: Mahmud TurkiaAFP]

The UN’s cultural organisation based its decision on two factors — “damage already caused” and vulnerability to future destruction.


It noted that “armed groups are present on these sites or in their immediate proximity”.


Experts fear worse is to come for the country’s historic sites, as armed groups continue to vie for ascendancy.











'Jewel of Roman Empire' faces Libya dangers
A picture taken on September 1, 2018 shows an edifice at the site of the ancient Roman city of Sabratha, around
70 kilometres from the Libyan capital Tripoli. The United Nations Educational, Scientific and Cultural
Organization (UNESCO) declared Sabratha to be at risk in July 2016, along with four
other Libyan sites on its World Heritage list [Credit: Mahmud TurkiaAFP]

Libya’s archaeological heritage is at great risk, warns Mohamad al-Chakchouki, head of the North African country’s department of antiquities.
The “entrenchment of armed groups inside archaeological sites and the battles which have unfolded near the sites, including Sabratha, pose a permanent danger”, he told AFP.


The conservation of sites was once entrusted to Western teams.











'Jewel of Roman Empire' faces Libya dangers
A picture taken on September 1, 2018 shows a portion of the site of the ancient Roman city of Sabratha, around
70 kilometres from the Libyan capital Tripoli. The United Nations Educational, Scientific and Cultural
Organization (UNESCO) declared Sabratha to be at risk in July 2016, along with four
other Libyan sites on its World Heritage list [Credit: Mahmud TurkiaAFP]

But these experts have not travelled to Libya “for four years, because of the chaos and insecurity”, said Chakchouki.


Spread out over 90 hectares (220 acres), including a part engulfed by the sea, Sabratha is one of three former cities that constituted Roman Tripolitania.


The others are Oea — modern-day Tripoli — and Leptis Magna in western Libya that was one of the sites classed as endangered by UNESCO two years ago.











'Jewel of Roman Empire' faces Libya dangers
A picture taken on September 1, 2018 shows columns of the amphitheatre at the site of the ancient Roman city of Sabratha,
 around 70 kilometres from the Libyan capital Tripoli. The United Nations Educational, Scientific and Cultural
Organization (UNESCO) declared Sabratha to be at risk in July 2016, along with four
other Libyan sites on its World Heritage list [Credit: Mahmud TurkiaAFP]

At the mercy of the scorching summer sun and the salty sea breeze, Sabratha suffers from stone erosion and degradation, said Mohamad Abu Ajela, an official at the city’s office of antiquities.


But the “damage caused by man is a greater fear”, he said.


A Spanish archaeological mission recently visited Sabratha and signed an agreement to restore some areas, including the theatre.


But completion of the work “depends on the security situation”, Ajela said.


Urbanisation and looting


Alongside armed conflict, several protected Libyan sites are threatened by uncontrolled urban expansion.











'Jewel of Roman Empire' faces Libya dangers
A picture taken on September 1, 2018 shows an edifice at the site of the ancient Roman city of Sabratha, around
70 kilometres from the Libyan capital Tripoli. The United Nations Educational, Scientific and Cultural
Organization (UNESCO) declared Sabratha to be at risk in July 2016, along with four
other Libyan sites on its World Heritage list [Credit: Mahmud TurkiaAFP]

One example is Cyrene, an ancient Greek city in northeastern Libya.


Exploiting the chaos, people have claimed ownership of land and built within the archaeological site’s perimeter.


Looting is another threat to these sites, as the lack of security has led to illicit excavation and smuggling of antiquities.











'Jewel of Roman Empire' faces Libya dangers
A picture taken on September 1, 2018 shows columns of the amphitheatre at the site of the ancient Roman city of Sabratha,
 around 70 kilometres from the Libyan capital Tripoli. The United Nations Educational, Scientific and Cultural
Organization (UNESCO) declared Sabratha to be at risk in July 2016, along with four
other Libyan sites on its World Heritage list [Credit: Mahmud TurkiaAFP]

Several thefts of ancient objects have been reported.
In March, Spain’s interior ministry announced the seizure “of numerous works of art” from the Cyrenaica and Tripolitania regions, including seven mosaics, sarcophagi and pieces of Egyptian origin.


Madrid said it had proof that two necropolises were looted by “terrorist groups”.











'Jewel of Roman Empire' faces Libya dangers
A picture shows a detail from a high reliefat the site of the ancient Roman city of Sabratha, around 70 kilometres from the
Libyan capital Tripoli. The United Nations Educational, Scientific and Cultural Organization (UNESCO) declared
Sabratha to be at risk in July 2016, along with four other Libyan sites on its World Heritage list
[Credit: Mahmud TurkiaAFP]

Officials in the antiquities department attempt to save what they can, often through desperate measures.


Museums have closed — including in Tripoli — and some archaeological treasures have been transferred to a “safe place”, Chakchouki said.


Source: AFP [October 03, 2018]



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Cuisine of early farmers revealed by analysis of proteins in pottery from Çatalhöyük

Knowledge of the diet of people living in the prehistoric settlement of Çatalhöyük almost 8000 years ago has been complemented in astonishing scope and detail by analyzing proteins from their ceramic bowls and jars. Using this new approach, an international team of researchers has determined that vessels from this early farming site in central Anatolia, in what is now Turkey, contained cereals, legumes, dairy products and meat, in some cases narrowing food items down to specific species.











Cuisine of early farmers revealed by analysis of proteins in pottery from Çatalhöyük
Examples of calcified deposits from modern and ancient vessels at Çatalhöyük. a) Example of extensive limescale build-up
on a modern tea water pot used near Çatalhöyük. b) A close-up of limescale deposits on an ancient sample. c) A relatively
intact vessel (not analyzed in this study) demonstrating bowl shape. d) A selection of 4 sherds analyzed
 in this study showing calcifications adhering to the inside surface of ceramic sherds
[Credit: Ingmar Franz; Hendy et al. Nature Communications, 2018]

An international team led by researchers from the Max Planck Institute for the Science of Human History, the Freie Universität Berlin and the University of York has uncovered details about the diet of early farmers in the central Anatolian settlement of Çatalhöyük.
By analyzing proteins from residues in ancient pots and jars excavated from the site, the researchers were able to find evidence of foods that were eaten there. Although previous studies have looked at pot residues from the site, this was the first to use proteins, which can be used to identify plants and animals more specifically, sometimes down to the species level.


One of the key early farming sites in the Old World


Çatalhöyük was a large settlement inhabited from about 7100 BC to 5600 BC by early farmers, and is located in what is now central Turkey. The site showcases a fascinating layout in which houses were built directly next to each other in every direction and stands out for its excellent preservation of finds. After over 25 years of excavation and analysis, it is considered one of the best-researched early farming sites in the Old World.











Cuisine of early farmers revealed by analysis of proteins in pottery from Çatalhöyük
Excavation of a trench on the West Mound [Credit: Jason Quinlan]

For this study, the researchers analyzed vessel sherds from the West Mound of Çatalhöyük, dating to a narrow timeframe of 5900-5800 BC towards the end of the site’s occupation. The vessel sherds analyzed came from open bowls and jars, as shown by reconstructions and had calcified residues on the inside surfaces.
In this region today, limescale residue on the inside of cooking pots is very common. The researchers used state-of-the-art protein analyses on samples taken from various parts of the ceramics, including the residue deposits, to determine what the vessels held.


Food proteins left behind in ceramic bowls and jars


The analysis revealed that the vessels contained grains, legumes, meat and dairy products. The dairy products were shown to have come mostly from sheep and goats, and also from the bovine (cattle) family. While bones from these animals are found across the site and earlier lipid analyses have identified milk fats in vessels, this is the first time researchers have been able to identify which animals were actually being used for their milk.











Cuisine of early farmers revealed by analysis of proteins in pottery from Çatalhöyük
Summary of dietary-derived protein identifications. The left graph summarizes proteins extracted from the sherd’s 
interior wall and the right graph summarizes proteins extracted from calcified deposits on the inner wall. Filled
 icons represent protein assignments to the genus or species level, while transparent icons represent identifications
to higher taxonomies (subfamily, family). In samples CW20 and CW27, blood protein was identified to the
taxonomic level of ruminant animals, which includes sheep and goats. In sample CW24, milk protein
could be assigned to either bovine or sheep families [Credit: Ingmar Franz; Hendy et al.
Nature Communications, 2018]

In line with the plant remains found, the cereals included barley and wheat, and the legumes included peas and vetches. The non-dairy animal products, which might have included meat and blood, came primarily from the goat and sheep family, and in some cases from bovines and deer. Interestingly, many of the pots contain evidence of multiple food types in a single vessel, suggesting that the residents mixed foods in their cuisine, potentially as porridges or soups, or that some vessels were used sequentially for different food items, or both.


Early cheese-making


One particular vessel however, a jar, only had evidence for dairy products, in the form of proteins found in the whey portion of milk. “This is particularly interesting because it suggests that the residents may have been using dairy production methods that separated fresh milk into curds and whey.


It also suggests that they had a special vessel for holding the whey afterwards, meaning that they used the whey for additional purposes after the curd was separated,” states Jessica Hendy, lead author, of the Max Planck Institute for the Science of Human History. These results show that dairying has been ongoing in this area since at least the 6th millennium BC, and that people used the milk of multiple difference species of animal, including cow, sheep and goat.











Cuisine of early farmers revealed by analysis of proteins in pottery from Çatalhöyük
Plan of Çatalhöyük showing the East and West Mounds and major excavation areas
[Credit: A. Bogaard et al., Anatolian Studies, 2017]

However, the researchers emphasize that based on the archaeological record an even greater variety of foods, especially plant foods, were likely eaten at Çatalhöyük, which either were not contained in the vessels they studied or are not present in the databases they use to identify proteins.


The “shotgun” proteomic approaches used by the researchers are heavily dependent on reference sequence databases, and many plant species are not represented or have limited representation. “For example, there are only 6 protein sequences for vetch in the databases. For wheat, there are almost 145,000,” explains Hendy. “An important aspect of future work will need to be expanding these databases with more reference sequences.”


The potential of protein analysis on archaeological ceramics


Other molecular techniques applied to ancient pottery can reveal broad classes of food – such as evidence of dairy or animal fat – but an analysis of proteins allows a much more detailed picture of past cuisine. The results of this study show the power of protein analyses, which can identify foodstuffs in situ down to the species level, in samples as old as 8000 years.


In particular, the residues on the insides of the ceramics were exceptionally well-preserved and contained a wealth of information. The removal of these residues can be a common practice among archaeologists as part of the preservation and cleaning process. “These results highlight how valuable these deposits can be, and we encourage colleagues to retain them during post-excavation processing and cleaning,” states Eva Rosenstock of the Freie Universität Berlin and the senior author of the study.


The findings are published in Nature Communications.


Source: Max Planck Society [October 03, 2018]



TANN



Archive


Awesome gravity



Credit: ESA/Hubble & NASA

Acknowledgement: Judy Schmidt

Gravity is so much a part of our daily lives that it is all too easy to forget its awesome power — but on a galactic scale, its power becomes both strikingly clear and visually stunning.


This image was taken with the NASA/ESA Hubble Space Telescope’s Wide Field Camera 3 (WFC3) and shows an object named SDSS J1138+2754. It acts as a gravitational lens illustrates the true strength of gravity: A large mass — a galaxy cluster in this case — is creating such a strong gravitational field that it is bending the very fabric of its surroundings. This causes the billion-year-old light from galaxies sitting behind it to travel along distorted, curved paths, transforming the familiar shapes of spirals and ellipticals (visible in other parts of the image) into long, smudged arcs and scattered dashes.


Some distant galaxies even appear multiple times in this image. Since galaxies are wide objects, light from one side of the galaxy passes through the gravitational lens differently than light from the other side. When the galaxies’ light reaches Earth it can appear reflected, as seen with the galaxy on the lower left part of the lens, or distorted, as seen with the galaxy to the upper right.


This data were taken as part of a research project on star formation in the distant Universe, building on Hubble’s extensive legacy of deep-field images. Hubble observed 73 gravitationally-lensed galaxies for this project.





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2018 October 3 NGC 1898: Globular Cluster in the Large…


2018 October 3


NGC 1898: Globular Cluster in the Large Magellanic Cloud
Image Credit: ESA/Hubble & NASA


Explanation: Jewels don’t shine this bright – only stars do. And almost every spot in this glittering jewel-box of an image from the Hubble Space Telescope is a star. Now some stars are more red than our Sun, and some more blue – but all of them are much farther away. Although it takes light about 8 minutes to reach Earth from the Sun, NGC 1898 is so far away that it takes light about 160,000 years to get here. This huge ball of stars, NGC 1898, is called a globular cluster and resides in the central bar of the Large Magellanic Cloud (LMC) – a satellite galaxy of our large Milky Way Galaxy. The featured multi-colored image includes light from the infrared to the ultraviolet and was taken to help determine if the stars of NGC 1898 all formed at the same time, or at different times. There are increasing indications that most globular clusters formed stars in stages, and that, in particular, stars from NGC 1898 formed shortly after ancient encounters with the Small Magellanic Cloud (SMC) and our Milky Way Galaxy.


∞ Source: apod.nasa.gov/apod/ap181003.html


Computer simulation follows light to supermassive black holes RIT-led study draws a...





Gas glows brightly in this screengrab of a computer simulation of supermassive black holes only 40 orbits from merging. Credit: NASA’s Goddard Space Flight Center


The hunt is on for orbiting pairs of supermassive black holes on the verge of collision. Researchers at Rochester Institute of Technology have built the first simulation that could lead scientists to them.



The predictive model tells astronomers how supermassive black hole binaries nearing merger at the center of active galaxies would look like through a modern telescope. The strong gravitational pull drawing the two supermassive black holes together creates violent shocks in surrounding gas producing light in the ultraviolet and X-ray wavelengths. Because current technology is unable to directly observe the gravitational wave frequency made by supermassive black hole binaries, scientists observe and measure light emitted along the electromagnetic spectrum and infer the boundaries of what they can yet see.


Predicting the characteristic light signals and the timing of their occurrence will help scientists identify these monster collisions with existing and future telescopes and better understand what is happening at the hearts of most galaxies, according to Manuela Campanelli, director of RIT’s Center for Computational Relativity and Gravitation and a co-author of the new study.


Findings from the paper, “Electromagnetic emission from supermassive binary black holes approaching merger,” appeared in the Oct. 2 issue of The Astrophysical Journal.


The study builds on a prior RIT study that suggests three gas disks as the light sources: two small companion disk of accreting gas feed each supermassive black hole; and a larger disk that contains the scenario playing out within its boundaries.


The computational model applies multi-messenger astronomy by combining information gathered from light- and gravitational waves, and high-energy particles. The mini-movies illustrating the simulation are the first to fully visualize the effects of Einstein’s general theory of relativity on the light and particles surrounding and passing between supermassive black holes orbiting each other.

“These are really beautiful images,” said Stéphane d’Ascoli, first author on the paper and a doctoral student at École Normale Supérieure in Paris. D’Ascoli collaborated with researchers at RIT’s Center for Computational Relativity and Gravitation, where he was a Visiting Scholar and Graduate Student Intern.


“You can see gravitational lensing and subtle effects we weren’t expecting, like ‘eyebrows,’ these secondary images of a black hole created by the way that light passes through the system,” he said.

D’Ascoli worked closely with Campanelli, who had initiated the project nine years ago, and with co-author and former post-doctoral fellow Scott Noble, now at NASA Goddard Space Flight Center. Additional co-authors on the paper include Dennis Bowen and Vassilios Mewes, Ph.D. students at RIT; and Julian Krolik from Johns Hopkins University.


“Identifying the light signatures from supermassive black hole binaries by some of the many electromagnetic telescopes operating now could jump-start the field of multimessenger astronomy and sharply refine our estimates of the population and evolution of supermassive black holes as well as guiding planning and development of space-based gravitational wave observatories,” Campanelli said.


Campanelli’s early research was instrumental to the first direct detection of stellar-mass binary black holes and discovery of gravitational waves by the LIGO-Virgo Collaboration. Stellar mass black holes result from supernovae explosions; supermassive black holes form when galaxies merge and drag along an entourage of gas and dust clouds, stars and planets.


“We know galaxies with central supermassive black holes combine all the time in the universe, yet we only see a small fraction of galaxies with two supermassive black holes near their center,” Noble said. “The ones we do see are not close enough to be emitting strong gravitational wave signals because they are too far away from each other. We are after seeing—with light—the close pairs, what we call binaries, for the first time.”


Campanelli’s team was one of the first to computationally simulate and predict gravitational wave signals from a stellar mass black hole merger a decade before LIGO directly observed the waveforms.

Future observatories like the Laser Interferometer Space Antenna (LISA), led by the European Space Agency, someday could directly detect gravitational waves from merging supermassive black holes. Ground-based observatories are unable to capture the long wavelengths of supermassive black holes. RIT’s Center for Computational Relativity are members of the LISA consortium.


The simulation ran on the National Center for Supercomputing Applications’ Blue Waters supercomputer at the University of Illinois at Urbana Champaign. Campanelli’s team was recently awarded additional time on Blue Waters to continue developing their models.


by Susan Gawlowicz
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Videos available:


Simulation Reveals Spiraling Supermassive Black Holes: Gas glows brightly in this computer simulation of supermassive black holes only 40 orbits from merging. Models like this may eventually help scientists pinpoint real examples of these powerful binary systems. Credit: NASA’s Goddard Space Flight Center


360-degree Simulated View of the Sky Between Two Supermassive Black Holes: This 360-degree video places the viewer in the middle of two circling supermassive black holes around 18.6 million miles (30 million kilometers) apart with an orbital period of 46 minutes. The simulation shows how the black holes distort the starry background and capture light, producing black hole silhouettes. A distinctive feature called a photon ring outlines the black holes. The entire system would have around 1 million times the Sun’s mass. Credit: NASA’s Goddard Space Flight Center; background, ESA/Gaia/DPAC




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New Simulation Sheds Light on Spiraling Supermassive Black Holes


NASA Goddard Space Flight Center logo.


Oct. 2, 2018


A new model is bringing scientists a step closer to understanding the kinds of light signals produced when two supermassive black holes, which are millions to billions of times the mass of the Sun, spiral toward a collision. For the first time, a new computer simulation that fully incorporates the physical effects of Einstein’s general theory of relativity shows that gas in such systems will glow predominantly in ultraviolet and X-ray light.


Just about every galaxy the size of our own Milky Way or larger contains a monster black hole at its center. Observations show galaxy mergers occur frequently in the universe, but so far no one has seen a merger of these giant black holes.


“We know galaxies with central supermassive black holes combine all the time in the universe, yet we only see a small fraction of galaxies with two of them near their centers,” said Scott Noble, an astrophysicist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “The pairs we do see aren’t emitting strong gravitational-wave signals because they’re too far away from each other. Our goal is to identify — with light alone — even closer pairs from which gravitational-wave signals may be detected in the future.”


A paper describing the team’s analysis of the new simulation was published Tuesday, Oct. 2, in The Astrophysical Journal and is now available online.



Simulation Reveals Spiraling Supermassive Black Holes

Video above: Gas glows brightly in this computer simulation of supermassive black holes only 40 orbits from merging. Models like this may eventually help scientists pinpoint real examples of these powerful binary systems. Video Credits: NASA’s Goddard Space Flight Center.


Scientists have detected merging stellar-mass black holes — which range from around three to several dozen solar masses — using the National Science Foundation’s Laser Interferometer Gravitational-Wave Observatory (LIGO). Gravitational waves are space-time ripples traveling at the speed of light. They are created when massive orbiting objects like black holes and neutron stars spiral together and merge.


Supermassive mergers will be much more difficult to find than their stellar-mass cousins. One reason ground-based observatories can’t detect gravitational waves from these events is because Earth itself is too noisy, shaking from seismic vibrations and gravitational changes from atmospheric disturbances. The detectors must be in space, like the Laser Interferometer Space Antenna (LISA) led by ESA (the European Space Agency) and planned for launch in the 2030s. Observatories monitoring sets of rapidly spinning, superdense stars called pulsars may detect gravitational waves from monster mergers. Like lighthouses, pulsars emit regularly timed beams of light that flash in and out of view as they rotate. Gravitational waves could cause slight changes in the timing of those flashes, but so far studies haven’t yielded any detections.


But supermassive binaries nearing collision may have one thing stellar-mass binaries lack — a gas-rich environment. Scientists suspect the supernova explosion that creates a stellar black hole also blows away most of the surrounding gas. The black hole consumes what little remains so quickly there isn’t much left to glow when the merger happens.


Supermassive binaries, on the other hand, result from galaxy mergers. Each supersized black hole brings along an entourage of gas and dust clouds, stars and planets. Scientists think a galaxy collision propels much of this material toward the central black holes, which consume it on a time scale similar to that needed for the binary to merge. As the black holes near, magnetic and gravitational forces heat the remaining gas, producing light astronomers should be able to see.



Animation above: This animation rotates 360 degrees around a frozen version of the simulation in the plane of the disk. Image Credits: NASA’s Goddard Space Flight Center.


“It’s very important to proceed on two tracks,” said co-author Manuela Campanelli, director of the Center for Computational Relativity and Gravitation at the Rochester Institute of Technology in New York, who initiated this project nine years ago. “Modeling these events requires sophisticated computational tools that include all the physical effects produced by two supermassive black holes orbiting each other at a fraction of the speed of light. Knowing what light signals to expect from these events will help modern observations identify them. Modeling and observations will then feed into each other, helping us better understand what is happening at the hearts of most galaxies.”


The new simulation shows three orbits of a pair of supermassive black holes only 40 orbits from merging. The models reveal the light emitted at this stage of the process may be dominated by UV light with some high-energy X-rays, similar to what’s seen in any galaxy with a well-fed supermassive black hole.


Three regions of light-emitting gas glow as the black holes merge, all connected by streams of hot gas: a large ring encircling the entire system, called the circumbinary disk, and two smaller ones around each black hole, called mini disks. All these objects emit predominantly UV light. When gas flows into a mini disk at a high rate, the disk’s UV light interacts with each black hole’s corona, a region of high-energy subatomic particles above and below the disk. This interaction produces X-rays. When the accretion rate is lower, UV light dims relative to the X-rays.


Based on the simulation, the researchers expect X-rays emitted by a near-merger will be brighter and more variable than X-rays seen from single supermassive black holes. The pace of the changes links to both the orbital speed of gas located at the inner edge of the circumbinary disk as well as that of the merging black holes.



360-degree Simulated View of the Sky Between Two Supermassive Black Holes

Video above: This 360-degree video places the viewer in the middle of two circling supermassive black holes around 18.6 million miles (30 million kilometers) apart with an orbital period of 46 minutes. The simulation shows how the black holes distort the starry background and capture light, producing black hole silhouettes. A distinctive feature called a photon ring outlines the black holes. The entire system would have around 1 million times the Sun’s mass. Video Credits: NASA’s Goddard Space Flight Center; background, ESA/Gaia/DPAC.


“The way both black holes deflect light gives rise to complex lensing effects, as seen in the movie when one black hole passes in front of the other,” said Stéphane d’Ascoli, a doctoral student at École Normale Supérieure in Paris and lead author of the paper. “Some exotic features came as a surprise, such as the eyebrow-shaped shadows one black hole occasionally creates near the horizon of the other.”


The simulation ran on the National Center for Supercomputing Applications’ Blue Waters supercomputer at the University of Illinois at Urbana-Champaign. Modeling three orbits of the system took 46 days on 9,600 computing cores. Campanelli said the collaboration was recently awarded additional time on Blue Waters to continue developing their models.



 Blue Waters Supercomputer. Image Credit: University of Illinois

The original simulation estimated gas temperatures. The team plans to refine their code to model how changing parameters of the system, like temperature, distance, total mass and accretion rate, will affect the emitted light. They’re interested in seeing what happens to gas traveling between the two black holes as well as modeling longer time spans.


“We need to find signals in the light from supermassive black hole binaries distinctive enough that astronomers can find these rare systems among the throng of bright single supermassive black holes,” said co-author Julian Krolik, an astrophysicist at Johns Hopkins University in Baltimore. “If we can do that, we might be able to discover merging supermassive black holes before they’re seen by a space-based gravitational-wave observatory.”


Related links:


The Astrophysical Journal: https://doi.org/10.3847/1538-4357/aad8b4


Laser Interferometer Gravitational-Wave Observatory (LIGO): https://www.ligo.caltech.edu/


Laser Interferometer Space Antenna (LISA): https://lisa.nasa.gov/


Center for Computational Relativity and Gravitation: https://ccrg.rit.edu/


Rochester Institute of Technology: https://www.rit.edu/


European Space Agency (ESA): https://www.esa.int/ESA


École Normale Supérieure de Paris: http://www.ens.fr/en


National Center for Supercomputing Applications: http://www.ncsa.illinois.edu/


Blue Waters supercomputer: http://www.ncsa.illinois.edu/enabling/bluewaters


University of Illinois at Urbana-Champaign: https://illinois.edu/


Johns Hopkins University: https://www.jhu.edu/


NASA’s Goddard Space Flight Center: https://www.nasa.gov/goddard


High-Tech Computing: https://www.nasa.gov/topics/technology/high-tech-computing/index.html


Black Holes: https://www.nasa.gov/black-holes


Animation (mentioned), Videos (mentioned), Text, Credits: NASA/Rob Garner/Goddard Space Flight Center, by Jeanette Kazmierczak.


Greetings, Orbiter.chArchive link


Cairnholy I Burial Chamber, Carsluith, Dumfries and Galloway, Scotland, 29.9.18.











Cairnholy I Burial Chamber, Carsluith, Dumfries and Galloway, Scotland, 29.9.18.


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