четверг, 30 августа 2018 г.

The Labyrinth, Clitheroe Castle, Lancashire, 30.8.18.



The Labyrinth, Clitheroe Castle, Lancashire, 30.8.18.


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Particles collected by Hayabusa give absolute age of asteroid Itokawa

Understanding the origin and time evolution of near-Earth asteroids (NEAs) is an issue of scientific interest and practical importance because they are potentially hazardous to the Earth. However, when and how these NEAs were formed and what they suffered during their lifetime remain enigmas.











Particles collected by Hayabusa give absolute age of asteroid Itokawa
Artist’s concept of Japan’s proposed Hayabusa 2 spacecraft, which would reconnoiter asteroid 1999 JU3 in mid-2018.
 Hayabusa 2 would hurl an impactor into the asteroid, sample the resulting crater and send pieces back
to Earth for study [Credit: JAXA/Akihiro Ikeshita]

Japanese scientists, including those from Osaka University, closely examined particles collected from the asteroid Itokawa by the spacecraft Hayabusa, finding that the parent body of Itokawa was formed about 4.6 billion years ago when the solar system was born and that it was destroyed by a collision with another asteroid about 1.5 billion years ago. Their research results were published in Scientific Reports.
Focusing on a few micrometers of phosphate minerals, which are rarely found in Itokawa particles, the scientists performed precise isotope analyses of uranium (U) and lead (Pb) in Itokawa particles of about 50 μm in diameter using Secondary Ion Mass Spectrometry (SIMS).











Particles collected by Hayabusa give absolute age of asteroid Itokawa
The cross section area of the particle collected from the asteroid Itokawa using Hayabusa spacecraft
[Credit: Osaka University]

Lead author Kentaro Terada says, “By combining two U decay series, 238U-206Pb (with a half-life of 4.47 billion years) and 235U-207Pb (with a half-life of 700 million years), using four Itokawa particles, we clarified that phosphate minerals crystalized during a thermal metamorphism age (4.64±0.18 billion years ago) of Itokawa’s parent body, experiencing shock metamorphism due to a catastrophic impact event by another body 1.51±0.85 billion years ago.”
It has been reported that the mineralogy and geochemistry of the Itokawa particles resemble those of LL (LL stands for Low (total) iron, Low metal) chondrites, which frequently fall to the Earth.











Particles collected by Hayabusa give absolute age of asteroid Itokawa
The time evolution of the asteroid Itokawa [Credit: Osaka University]

However, the shock ages of Itokawa particles obtained from this study (1.5 billion years ago) are different from previously reported shock ages of shocked LL chondrites (4.2 billion years ago). This shows that the asteroid Itokawa had a time evolution different from that of the parent body of LL chondrites.


The results of this study established constraints on the timescale of the first samples collected from the asteroid, providing concrete figures (absolute age) to the evolution of the NEAs whose orbits are well known. This will lead to the elucidation of the origins and histories of asteroids.


Source: Osaka University [August 27, 2018]



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Jupiter had growth disorders

With an equator diameter of around 143,000 kilometers, Jupiter is the largest planet in the solar system and has 300 times the mass of the Earth. The formation mechanism of giant planets like Jupiter has been a hotly debated topic for several decades. Now, astrophysicists of the Swiss National Centre of Competence in Research (NCCR) PlanetS of the Universities of Bern and Zürich and ETH Zürich have joined forces to explain previous puzzles about how Jupiter was formed and new measurements. The research results were published in the magazine Nature Astronomy.











Jupiter had growth disorders
Jupiter’s southern hemisphere photographedby NASA’s Juno spacecraft [Credit: NASA/JPL-
Caltech/SwRI/MSSS/GeraldEichstaedt/Sean Doran]

“We could show that Jupiter grew in different, distinct phases,” explains Julia Venturini, postdoc at the University of Zürich. “Especially interesting is that it is not the same kind of bodies that bring mass and energy,” adds Yann Alibert, Science Officer of PlanetS and first author of the paper.


First, the planetary embryo rapidly accreted small, centimeter-sized pebbles and quickly built a core during the initial one million years. The following two million years were dominated by slower accretion of larger, kilometer-sized rocks called planetesimals. They hit the growing planet with great energy, releasing heat.


“During the first stage the pebbles brought the mass,” Yann Alibert explains: “In the second phase, the planetesimals also added a bit of mass, but what is more important, they brought energy.” After three million years, Jupiter had grown to a body of 50 Earth masses. Then, the third formation phase started dominated by gas runaway accretion leading to today’s gas giant with more than 300 Earth masses.


Solar system divided into two parts


The new model for Jupiter’s birth matches the meteorite data that were presented at a conference in the US last year. At first, Julia Venturini and Yann Alibert were puzzled when they listened to the results. Measurements of the composition of meteorites showed that in the primordial times of the solar system the solar nebula was divided into two regions during two million years. It could therefore be concluded that Jupiter acted as a kind of a barrier when it grew from 20 to 50 Earth masses.











Jupiter had growth disorders
The formation of Jupiter in 3 stages.Stage 1 / until 1 million years: Jupiter grows byaccretion of pebbles (blue dots).
Largeprimordial planetesimals (big red dots) showhigh collision velocities (red arrows) leading todestructive
collisions (yellow) and producingsmall, second generation planetesimals (smallred dots).Stage 2 / 1-3 million years:
The energy resultingfrom the accretion of small planetesimalsprevents rapid gas accumulation and thus
rapidgrowth (gray arrows).Stage 3 / beyond 3 million years: Jupiter ismassive
enough to accrete large amounts of gas [Credit: UniBE]

During this period, the forming planet must have perturbed the dust disk, creating an over-density that trapped the pebbles outside of its orbit. Therefore, material from outward regions could not mix with material of the inner ones until the planet reached enough mass to perturb and scatter rocks inwards. “How could it have taken two million years for Jupiter to grow from 20 to 50 Earth masses?” asked Julia Venturini. “That seemed much too long,” she explains: “That was the triggering question that motivated our study.”
A discussion by email started among NCCR PlanetS researchers of the Universities of Bern and Zürich and ETH Zürich and the following week the experts in the fields of astrophysics, cosmochemistry and hydrodynamics arranged a meeting in Bern. “In a couple of hours we knew what we had to calculate for our study,” says Yann Alibert: “This was only possible within the framework of the NCCR, which links scientists from various fields.”


Explanation for delayed growth


With their calculations, the researchers showed that the time the young planet spent in the mass range of 15 to 50 Earth masses was indeed much longer than previously thought. During this formation phase the collisions with the kilometer-sized rocks provided enough energy to heat the gaseous atmosphere of the young Jupiter and prevented rapid cooling, contraction and further gas accretion.











Jupiter had growth disorders
Jupiter photographed by NASA’s Cassini spacecraft [Credit: NASA/JPL/University of Arizona]

“Pebbles are important in the first stages to build a core quickly, but the heat provided by planetesimals is crucial to delay gas accretion so that it matches the timescale given by the meteorite data,” the astrophysicists summarize. They are convinced that their results provide as well key elements for solving long-standing problems of the formation of Uranus and Neptune and exoplanets in this mass regime.


Source: University of Zurich [August 27, 2018]




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Orionid Meteor Shower 2017

One of the best meteor showers of the annual calendar occurs this weekend. The Orionids often produce very bright and fast meteors. The name is given because of the direction from which the meteors radiate from, namely the constellation of Orion. The meteor shower is expected to produce around 20 meteors per hour at its peak however this number can fluctuate. 


Where do they come from?


The particles that produce these ‘shooting stars’ originate from Halley’s Comet. Categorised as a short period comet, the famous piece of ice and dust has an orbital period of 75-76 years. The comet has left a steady stream of dust and particles around its orbit path in the solar system. October 20-21 is when the Earth passes through this orbit head on each year producing the meteor shower. So effectively when observing the Orionid meteor shower, you are watching little pieces of Halley’s Comet burn up in the sky.


How to view the Orionids


As the meteors radiate from the constellation of Orion, the best time to view them is when the radiant is at its highest point in the sky. The radiant is located near Orion’s sword, slightly north of his left shoulder. The bright orange star Betelgeuse is just below and to the right of this area of the sky. The constellation of Orion doesn’t rise fully until after midnight. The best time to view the Orionid meteor shower is in the early hours of Sunday 22 October (night of Saturday 21st) ideally after 1:30 a.m. With the Moon out of the way this year, some decent hourly rates of meteors should be seen from a dark sky site. Even from towns and cities there are still chances of seeing a few per hour as many of these meteors can be bright.


Even though the shooting stars radiate from the constellation of Orion, it’s best not to look straight at Orion as the meteors only begin here and often streak a long way across the sky. Their brightest point may by high overhead or even over in the Northern or Western sky. The best advice is to find a way to comfortably lie on your back, look up and keep warm. Staying still for long periods of time in the early hours of an October night will rapidly get you shivering without appropriate clothing (and thermos flask). Layer up and make sure you wear a hat.


The illustration above shows where the radiant is in the sky for the Orionids but as said before, this is not the ideal place in the sky to stare at if you want to see plenty of the meteors. 


Orionid Meteor Shower Illustration
Click to enlarge

 


The post Orionid Meteor Shower 2017 appeared first on Comet Watch.


NASA’s Satellite Data Help Save Lives

For the first time, measurements from our Earth-observing satellites

are being used to help combat a potential outbreak of life-threatening cholera.

Humanitarian teams in Yemen are targeting areas identified by a NASA-supported

project that precisely forecasts high-risk regions based on environmental

conditions observed from space.


image

Cholera is caused by consuming food or water contaminated with a

bacterium called Vibrio cholerae.


image

The disease affects millions of people every year and can be

deadly. It remains a major threat to global health, especially in developing

countries, such as Yemen, where access to clean water is limited.


image

To calculate the likelihood of an outbreak, scientists run a

computer model that takes satellite

observations of things like rain and temperatures and combines them with

information on local sanitation and clean water infrastructure. In 2017,

the model achieved 92 percent

accuracy in predicting the regions where cholera was most likely to occur and

spread in Yemen. An outbreak that year in Yemen was the world’s worst, with

more than 1.1 million suspected cases and more than 2,300 deaths, according to

the World Health Organization.


image

International humanitarian organizations took notice. In January 2018, Fergus McBean,

a humanitarian adviser with

the U.K.’s Department for International Development, read about the NASA-funded

team’s 2017 results and contacted them with an ambitious challenge: to create

and implement a cholera forecasting system for Yemen, in only four months.


“It was a race against the start of rainy season,” McBean

said.


The U.S. researchers began working with U.K. Aid, the U.K.

Met Office, and UNICEF on the innovative approach to use the model to inform

cholera risk reduction in Yemen.


In March,

one month ahead of the rainy season, the U.K. international development office

began using the model’s forecasts. Early results show the science team’s model

predictions, coupled with Met Office weather forecasts, are helping UNICEF and

other aid groups target their response to where support is needed most.


image


Photo Credit: UNICEF



“By joining up international expertise with those working on

the ground, we have for the very first time used these sophisticated

predictions to help save lives and prevent needless suffering,” said Charlotte

Watts, chief scientist for United Kingdom’s Department for International Development.


Read more: go.nasa.gov/2MxKyw4




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2018 August 30 The NGC 6914 Complex Image Credit &…


2018 August 30


The NGC 6914 Complex
Image Credit & Copyright: Ivan Eder


Explanation: A study in contrasts, this colorful skyscape features stars, dust, and glowing gas in the vicinity of NGC 6914. The complex of reflection nebulae lies some 6,000 light-years away, toward the high-flying northern constellation Cygnus and the plane of our Milky Way Galaxy. Obscuring interstellar dust clouds appear in silhouette while reddish hydrogen emission nebulae, along with the dusty blue reflection nebulae, fill the cosmic canvas. Ultraviolet radiation from the massive, hot, young stars of the extensive Cygnus OB2 association ionize the region’s atomic hydrogen gas, producing the characteristic red glow as protons and electrons recombine. Embedded Cygnus OB2 stars also provide the blue starlight strongly reflected by the dust clouds. The nearly 1 degree wide telescopic field of view spans about 100 light-years at the estimated distance of NGC 6914.


∞ Source: apod.nasa.gov/apod/ap180830.html


How a NASA Scientist Looks in the Depths of the Great Red Spot to Find Water on Jupiter


NASA – JUNO Mission logo.


Aug. 29, 2018


For centuries, scientists have worked to understand the makeup of Jupiter. It’s no wonder: this mysterious planet is the biggest one in our solar system by far, and chemically, the closest relative to the Sun. Understanding Jupiter is key to learning more about how our solar system formed, and even about how other solar systems develop.


But one critical question has bedeviled astronomers for generations: Is there water deep in Jupiter’s atmosphere, and if so, how much?


Gordon L. Bjoraker, an astrophysicist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, reported in a recent paper in the Astronomical Journal that he and his team have brought the Jovian research community closer to the answer.


By looking from ground-based telescopes at wavelengths sensitive to thermal radiation leaking from the depths of Jupiter’s persistent storm, the Great Red Spot, they detected the chemical signatures of water above the planet’s deepest clouds. The pressure of the water, the researchers concluded, combined with their measurements of another oxygen-bearing gas, carbon monoxide, imply that Jupiter has 2 to 9 times more oxygen than the Sun. This finding supports theoretical and computer-simulation models that have predicted abundant water (H2O) on Jupiter made of oxygen (O) tied up with molecular hydrogen (H2).



Fly into the Great Red Spot of Jupiter with NASA’s Juno Mission

Video above: This animation takes the viewer on a simulated flight into, and then out of, Jupiter’s upper atmosphere at the location of the Great Red Spot. It was created by combining an image from the JunoCam imager on NASA’s Juno spacecraft with a computer-generated animation. The perspective begins about 2,000 miles (3,000 kilometers) above the cloud tops of the planet’s southern hemisphere. The bar at far left indicates altitude during the quick descent; a second gauge next to that depicts the dramatic increase in temperature that occurs as the perspective dives deeper down. The clouds turn crimson as the perspective passes through the Great Red Spot. Finally, the view ascends out of the spot.Video Credits: NASA/JPL.


The revelation was stirring given that the team’s experiment could have easily failed. The Great Red Spot is full of dense clouds, which makes it hard for electromagnetic energy to escape and teach astronomers anything about the chemistry within.


“It turns out they’re not so thick that they block our ability to see deeply,” said Bjoraker. “That’s been a pleasant surprise.”


New spectroscopic technology and sheer curiosity gave the team a boost in peering deep inside Jupiter, which has an atmosphere thousands of miles deep, Bjoraker said: “We thought, well, let’s just see what’s out there.”


The data Bjoraker and his team collected will supplement the information NASA’s Juno spacecraft is gathering as it circles the planet from north to south once every 53 days.


Among other things, Juno is looking for water with its own infrared spectrometer and with a microwave radiometer that can probe deeper than anyone has seen — to 100 bars, or 100 times the atmospheric pressure at Earth’s surface. (Altitude on Jupiter is measured in bars, which represent atmospheric pressure, since the planet does not have a surface, like Earth, from which to measure elevation.)


If Juno returns similar water findings, thereby backing Bjoraker’s ground-based technique, it could open a new window into solving the water problem, said Goddard’s Amy Simon, a planetary atmospheres expert.


“If it works, then maybe we can apply it elsewhere, like Saturn, Uranus or Neptune, where we don’t have a Juno,” she said.



Image above: This visualization was created from images captured by NASA’s Juno spacecraft, which has been studying Jupiter since it arrived there July 4, 2016. Image Credit: NASA/JPL/SwRI.


Juno is the latest spacecraft tasked with finding water, likely in gas form, on this giant gaseous planet.


Water is a significant and abundant molecule in our solar system. It spawned life on Earth and now lubricates many of its most essential processes, including weather. It’s a critical factor in Jupiter’s turbulent weather, too, and in determining whether the planet has a core made of rock and ice.


Jupiter is thought to be the first planet to have formed by siphoning the elements left over from the formation of the Sun as our star coalesced from an amorphous nebula into the fiery ball of gases we see today. A widely accepted theory until several decades ago was that Jupiter was identical in composition to the Sun; a ball of hydrogen with a hint of helium — all gas, no core.


But evidence is mounting that Jupiter has a core, possibly 10 times Earth’s mass. Spacecraft that previously visited the planet found chemical evidence that it formed a core of rock and water ice before it mixed with gases from the solar nebula to make its atmosphere. The way Jupiter’s gravity tugs on Juno also supports this theory. There’s even lightning and thunder on the planet, phenomena fueled by moisture.


“The moons that orbit Jupiter are mostly water ice, so the whole neighborhood has plenty of water,” said Bjoraker. “Why wouldn’t the planet — which is this huge gravity well, where everything falls into it — be water rich, too?”


The water question has stumped planetary scientists; virtually every time evidence of H2O materializes, something happens to put them off the scent. A favorite example among Jupiter experts is NASA’s Galileo spacecraft, which dropped a probe into the atmosphere in 1995 that wound up in an unusually dry region. “It’s like sending a probe to Earth, landing in the Mojave Desert, and concluding the Earth is dry,” pointed out Bjoraker.


In their search for water, Bjoraker and his team used radiation data collected from the summit of Maunakea in Hawaii in 2017. They relied on the most sensitive infrared telescope on Earth at the W.M. Keck Observatory, and also on a new instrument that can detect a wider range of gases at the NASA Infrared Telescope Facility.



Image above: The Great Red Spot is the dark patch in the middle of this infrared image of Jupiter. It is dark due to the thick clouds that block thermal radiation. The yellow strip denotes the portion of the Great Red Spot used in astrophysicist Gordon L. Bjoraker’s analysis. Image Credits: NASA’s Goddard Space Flight Center/Gordon Bjoraker.


The idea was to analyze the light energy emitted through Jupiter’s clouds in order to identify the altitudes of its cloud layers. This would help the scientists determine temperature and other conditions that influence the types of gases that can survive in those regions.


Planetary atmosphere experts expect that there are three cloud layers on Jupiter: a lower layer made of water ice and liquid water, a middle one made of ammonia and sulfur, and an upper layer made of ammonia.


To confirm this through ground-based observations, Bjoraker’s team looked at wavelengths in the infrared range of light where most gases don’t absorb heat, allowing chemical signatures to leak out. Specifically, they analyzed the absorption patterns of a form of methane gas. Because Jupiter is too warm for methane to freeze, its abundance should not change from one place to another on the planet.


“If you see that the strength of methane lines vary from inside to outside of the Great Red Spot, it’s not because there’s more methane here than there,” said Bjoraker, “it’s because there are thicker, deep clouds that are blocking the radiation in the Great Red Spot.”



Juno spacecraft orbiting Jupiter. Animation Credit: NASA

Bjoraker’s team found evidence for the three cloud layers in the Great Red Spot, supporting earlier models. The deepest cloud layer is at 5 bars, the team concluded, right where the temperature reaches the freezing point for water, said Bjoraker, “so I say that we very likely found a water cloud.” The location of the water cloud, plus the amount of carbon monoxide that the researchers identified on Jupiter, confirms that Jupiter is rich in oxygen and, thus, water.


Bjoraker’s technique now needs to be tested on other parts of Jupiter to get a full picture of global water abundance, and his data squared with Juno’s findings.


“Jupiter’s water abundance will tell us a lot about how the giant planet formed, but only if we can figure out how much water there is in the entire planet,” said Steven M. Levin, a Juno project scientist at NASA’s Jet Propulsion Laboratory in Pasadena, California.


Related links:


Astronomical Journal: https://doi.org/10.3847/1538-3881/aad186


NASA’s Juno spacecraft: https://www.nasa.gov/mission_pages/juno/main/index.html


Images (mentioned), Animation (mentioned), Video (mentioned), Text, Credits: NASA/Karl Hille/Goddard Space Flight Center, by Lonnie Shekhtman.


Greetings, Orbiter.chArchive link


Looted Icon of St George returns to Cyprus

An 1829 Greek Orthodox icon of St. George, looted from the village of Karavas, in Cyprus following the 1974 Turkish invasion, is set to be repatriated, after it was confiscated by the Swiss authorities.











Looted Icon of St George returns to Cyprus
Credit: Cyprus News Agency

The icon was confiscated only hours before going to auction in Koller, an auction house in Zurich. The legal process was completed in less than a year, following close cooperation between the Church of Cyprus, Cypriot and Swiss authorities.
The icon is now in Cypriot hands in Switzerland and will be repatriated by a Church of Cyprus representative.


The present owner was not aware that the icon was stolen and accepted to return it to the Cypriot authorities after he learned about its provenance. There are no details about the nationality of the owner or the way he came into possession of the icon.


Author: Tasos Kokkinidis | Source: The Greek Reporter [August 26, 2018]



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Scientists find corals in deeper waters under stress too

Coral reefs around the world are threatened by warming ocean temperatures, a major driver of coral bleaching. Scientists routinely use sea-surface temperature data collected by satellites to predict the temperature-driven stress on reef communities, but new research shows that surface measurements alone may not accurately predict the full extent of thermal stress on deeper corals.











Scientists find corals in deeper waters under stress too
A scientific diver with the Coral Reef Research Foundation (CRRF) ascends a reef wall in Palau at a depth of 90 meters
(295 feet). The diver was on a mission to photograph mesophotic coral ecosystems and recover temperature
gauges deployed the prior year [Credit: Patrick Colin, CRRF]

A new study led by scientists at Scripps Institution of Oceanography at the University of California San Diego and the Coral Reef Research Foundation (CRRF) in Palau describes a novel approach for predicting warm temperature-induced stress on corals from the sea surface through a deeper expanse ranging from 30-150 meters (100-500 feet) known as the mesophotic zone.


Corals at this depth are thought of by some in the science community as being safer from ocean warming than their shallow-water counterparts. But the Scripps Oceanography team found that even in the deep, corals are episodically exposed to thermal stress at intervals different than those corals near the surface.


The researchers utilized nearly two decades of data sets — including sea level, sea-surface temperature, and temperature observations that ranged between the surface and deep into the mesophotic zone — to develop a forecast tool for the vertical extent of how corals will be stressed by temperature. This research was conducted at three reef locations around the island nation of Palau, located in the tropical Pacific Ocean.


This novel approach to measure and predict temperature stress on coral reefs is described in a new study published in the journal Geophysical Research Letters.


“We’re now adding the dimension of depth into the problem where before we were only skimming the surface of what temperature stress meant for corals,” said Scripps PhD candidate Travis Schramek, lead author of the study. “We see that the heat-induced stress penetrates all the way into the mesophotic zone during larger bleaching events.”



In addition to looking at sea-surface temperature data collected by global satellites, the scientists used a network of reef temperature recorders maintained by CRRF divers in key locations across Palau down to depths of 90 meters (295 feet).


CRRF has maintained this array of temperature gauges across Palau, stretching from the surface to the mesophotic reefs since 1999. Only a small number of divers in the world possess the training, skills, and equipment to safely and routinely dive in the mesophotic zone. One of these rare scientific divers is Pat Colin, director of CRRF and a coauthor of the study.


For nearly 20 years, Colin and a small team have conducted weekly dives at locations across Palau as part of a long-term temperature-monitoring program. Surveys to assess bleaching in the mesophotic zone are severely limited, so the Scripps team, which included scientists Mark Merrifield and Eric Terrill, found Colin’s observational data sets to be incredibly valuable.


The observations showed that deeper zones are showing bleaching coincident with the higher temperatures, right along with shallow reefs.


“Our understanding of the ocean is really going to continue to be driven by observations. The models are really informative, but the way that we ground them is through observing the Earth system,” said Schramek. “Having observations like what Pat has collected shows the power of actually going and deploying tools and observing Earth in a unique way.”


The researchers said they hope these results will instigate more temperature stress event surveys to better understand the mesophotic zone in Palau and other tropical regions. They also looked at daily tide gauge records from the Malakal Harbor station in Palau from 1970-2017. This data, collected by the University of Hawaii Sea Level Center, allowed the team to study the regional sea level records in the area.











Scientists find corals in deeper waters under stress too
The teal blue waters of the lagoon drop rapidly off into the deep ocean in the southern extent of Palau
[Credit: Travis Schramek, Scripps Institution of Oceanography, UC San Diego]

By coupling sea level and sea temperature data sets, Schramek found that the height of the ocean surface is a strong indicator of how water temperatures are changing tens of meters below. He and the team then further used this data to predict the temperatures experienced by coral reefs living near the surface, as well as those living in deeper waters. Schramek developed an algorithm to apply the accepted coral stress algorithms to depths that included the deeper mesophotic, typically thought to be a refuge from thermal stress.


“A surprising outcome of the study is that the oceanic conditions along the dramatic reef walls that are the boundaries of Palau are very representative of the broader Western Pacific,” said Scripps oceanographer Terrill. “As a result, we had a surprising amount of success in predicting the vertical structure of the temperature fields that the coral communities would be exposed to, even during El Niño conditions.”


He added that the results suggest promise in applying the method to the other islands in this Pacific region that don’t benefit from the long-term time records that Palau has as a result of CRRF’s dedicated measurement campaign.


The team’s new insights on how to predict temperature stress on deep corals may contribute to a better understanding of the entire reef system as a whole, which could inform conservation and policy efforts to protect this valuable and diverse ecosystem.


“Now that we’ve observed this ecosystem in a unique way, we can start to better assess how corals in the mesophotic zone are stressed,” said Schramek. “If we can better understand how they’re stressed, then we can better understand how to protect them.”


Author: Brittany Hook | Source: Scripps Institution of Oceanography, UC San Diego [August 27, 2018]



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Scientists ‘fix’ bacterial tree of life

Bacterial classification has been given a complete makeover by a team of University of Queensland researchers, using an evolutionary tree based on genome sequences.











Scientists 'fix' bacterial tree of life
The ‘tree of life’ for the bacterial world, bacteria’s taxonomy in a phylogenetic tree
[Credit: The University of Queensland]

The study, led by Professor Philip Hugenholtz from UQ’s School of Chemistry and Molecular Biosciences and the Australian Centre for Ecogenomics (ACE), relied on a technique called metagenomics, where bacterial genomes are obtained straight from environmental samples, to create a more complete picture of the structure of the bacterial kingdom.


Professor Hugenholtz said this structure, known scientifically as taxonomy, helps us connect the relationships between living things.


“Taxonomy helps us classify living things by arranging them in a hierarchy from closely to distantly related organisms according to ranks, such as species, genus, family, order, class, phylum and domain,” he said.


“It’s a system that helps us understand how organisms are related to each other, just like we do for time – using seconds, minutes, hours, and so on – or for geographic locations, using a street number, street, suburb, state and country.”


Professor Hugenholtz said the scientific community generally agrees that evolutionary relationships are the most natural way to classify organisms, but bacterial taxonomy is riddled with errors, due to historical difficulties.


“This is mainly because microbial species have very few distinctive physical features, meaning that there are thousands of historically misclassified species,” he said.


“It’s also compounded by the fact that we can’t yet grow the great majority of microorganisms in the laboratory, so have been unaware of them until quite recently.”


Dr Donovan Parks, the lead software developer on the project, is excited about the recent advancement of genome sequencing technology, and how it’s helping reconstruct the bacterial tree of life.


“It’s developed to a remarkable degree, and we can now get the entire genetic blueprints of hundreds of thousands of bacteria, including bacteria that have not yet been grown in the lab,” he said.


The research team then used these genomic blueprints to construct a giant evolutionary tree of bacteria based on 120 genes that are highly conserved across the bacterial domain.


“This tree helped us create a standardised model, where we fixed all of the misclassifications and made the evolutionary timelines between bacterial groups consistent,” Dr Parks said.


“For example, the genus Clostridium has been a dumping ground for rod-shaped bacteria that produce spores inside their cells, so we reclassified this group into 121 separate genus groups across 29 different families.


“We’ve given bacterial classification a complete makeover, and we’re delighted that the scientific community is just as excited about this as we are.”


The study has been published in Nature Biotechnology.


Source: University of Queensland [August 27, 2018]



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Geologists uncover new clues about largest mass extinction ever

A new study could help explain the driving force behind the largest mass extinction in the history of earth, known as the End-Permian Extinction.











Geologists uncover new clues about largest mass extinction ever
The photo depicts a sample of mantle xenolith, rock sections of the lithosphere that get captured
by the passing magma and erupted to the surface during the volcanic explosion
[Credit: Michael W. Broadley]

The event, also known as the Great Dying, occurred around 250 million years ago when a massive volcanic eruption in what is today the Russian province of Siberia sent nearly 90 percent of all life right into extinction. Geologists call this eruption the Siberian Flood Basalts, and it ran for almost a million years.


“The scale of this extinction was so incredible that scientists have often wondered what made the Siberian Flood Basalts so much more deadly than other similar eruptions,” said Michael Broadley, a postdoctoral researcher at the Centre for Petrographic and Geochemical Research in Vandœuvre-lès-Nancy, France, and lead author of the paper.


The work, which was published in Nature Geoscience, was co-authored by Lawrence (Larry) Taylor, the former director of the Planetary Geosciences Institute at the University of Tennessee, Knoxville. Taylor, whose prolific career at UT spanned 46 years, passed away in September 2017 at age 79.


According to Broadley, “Taylor was instrumental in supplying samples of mantle xenoliths, rock sections of the lithosphere [a section of the planet located between the crust and the mantle] that get captured by the passing magma and erupted to the surface during the volcanic explosion. Taylor also provided advice throughout the study.”


Through the analysis of samples, Broadley and his team tried to determine the composition of the lithosphere. They found that before the Siberian Flood Basalts took place, the Siberian lithosphere was heavily loaded with chlorine, bromine, and iodine, all chemical elements from the halogen group. However, these elements seem to have disappeared after the volcanic eruption.


“We concluded that the large reservoir of halogens that was stored in the Siberian lithosphere was sent into the earth’s atmosphere during the volcanic explosion, effectively destroying the ozone layer at the time and contributing to the mass extinction,” Broadley said.


Source: University of Tennessee at Knoxville [August 27, 2018]



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Orbital Residents Supporting Human Research and Life Support Maintenance


ISS – Expedition 56 Mission patch.


August 29, 2018



International Space Station (ISS). Image Credit: NASA

The six residents aboard the International Space Station today continued exploring how living in space impacts their bodies. The Expedition 56 crew also worked on science hardware and life support gear to ensure the orbital complex is in tip-top shape.


Three astronauts helped doctors understand what is happening to their eyes in the weightless environment of microgravity. One crew member has also worked all week on a pair of European experiments researching what happens during exercise and cognition on long-term missions in space.



Image above: Expedition 56/57 crew members (clockwise from top) Alexander Gerst, Serena Auñón-Chancellor and Sergey Prokopyev pose for a portrait inside the Bigelow Expandable Aerospace Module (BEAM). Image Credit: NASA.


NASA astronauts Ricky Arnold and Serena Auñón-Chancellor joined ESA astronaut Alexander Gerst for more regularly scheduled eye checks today. Arnold led the morning’s retina scans using optical coherence tomography on the other two crewmates. Later in the afternoon, Auñón-Chancellor and Gerst swapped medical roles and peered into each other’s eyes looking out the optic disc and macula with a fundoscope.


Gerst continued working out today in a custom t-shirt in a specialized fabric testing its comfort and thermal relief for the SpaceTex-2 study. He then moved on to the GRIP study exploring how microgravity impacts an astronaut’s cognition when working with tools and interfaces aboard spacecraft.



Image above: Flying over South Africa, seen by EarthCam on ISS, speed: 27’585 Km/h, altitude: 412,99 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 August 29, 2018 at 14:45 UTC. Image Credits: Orbiter.ch Aerospace/Roland Berga.


Commander Drew Feustel worked on the Materials Science Research Rack today replacing gear inside the refrigerator-sized device that can heat research samples to a temperature of 2500° F. Cosmonauts Oleg Artemyev and Sergey Prokopyev spent the afternoon checking the Vozdukh carbon dioxide removal device for leaks in the Russian segment of the station.


Related links:


Expedition 56: https://www.nasa.gov/mission_pages/station/expeditions/expedition56/index.html


SpaceTex-2: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7571


GRIP: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=1188


Materials Science Research Rack: https://www.nasa.gov/sites/default/files/380893main_MSRR_factsheet.pdf


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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Upper Cretaceous trench deposits of the Neo-Tethyan subduction zone in Tibet

The Jiachala Formation was fed largely from the Gangdese arc have long been considered as syn-collisional foreland-basin deposits based on the reported occurrence of Paleocene-early Eocene dinoflagellate cysts and pollen assemblages. Because magmatic activity in the Gangdese arc continued through the Late Cretaceous and Paleogene, this scenario is incompatible with U-Pb ages of detrital zircons invariably older than the latest Cretaceous.











Upper Cretaceous trench deposits of the Neo-Tethyan subduction zone in Tibet
Paleogeographic scenario for the Jiachala Formation. a) Jiachala Formation, b)&c)
other trench deposits to the west [Credit: ©Science China Press]

In order to solve this incongruence and constrain the depositional age and tectonic setting of the Jiachala Formation, a new research was carried out with stratigraphic, sedimentological, provenance analysis including sandstone petrography, detrital zircon U-Pb age and Hf isotopic data; and paleontological analysis by Prof. Xiumian Hu’s group at Nanjing University.


According to this research, the Jiachala Formation was originally deposited on a submarine fan in the trench environment at the active southern margin of the Asian plate. Sandstone petrography, detrital-zircon U-Pb ages and Hf isotope ratios indicate provenance from the Gangdese arc and the central Lhasa terrane.


Because magmatic activity in the Gangdese arc was virtually continuous, the youngest population of detrital zircons contained in the Jiachala Formation constrain its depositional age as Late Cretaceous (~88-84 Ma). What’s more, based on the U-Pb age spectra of detrital zircons and sandstone petrography, there are no Paleocene-Eocene units similar to the Jiachala Formation which compares well with Upper Cretaceous exposed within and close to the Yalung Zangbo suture zone.


Integrated geological information indicates that the Jiachala Formation accumulated in the Neo-Tethyan trench during subduction of oceanic lithosphere. In summary, this research gives a new interpretation about the Jiachala Formation and enriches the case study of the arc trench system of the active Asian continental margin.


The findings are published in Science China Earth Sciences.


Source: Science China Press [August 27, 2018]



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New clues unearthed about mammals’ rapid evolution after dinosaur extinction

It was a life-altering event. Around 66 million years ago, at the end of the Cretaceous period, an asteroid struck the Earth, triggering a mass extinction that killed off the dinosaurs and some 75% of all species. Somehow mammals survived, thrived, and became dominant across the planet. Now we have new clues about how that happened.











New clues unearthed about mammals' rapid evolution after dinosaur extinction
The extinction of the dinosaurs paved the way for today’s mammalian diversity
[Credit: Petr Kratochvil/Public Domain Pictures]

Dr. Steve Brusatte, a palaeontologist at the University of Edinburgh, UK, who previously studied the dinosaurs’ extinction, sought to understand exactly how this event affected mammals and their evolution.


‘I wanted to find out where mammals were living, what were their habits … and how this exciting period of evolution set the stage for the great diversity of mammals that exists today,’ he said.


His work revealed that while many mammals were wiped out with the dinosaurs, there was also an increase in the diversity and abundance of those that did survive.


As part of the four-year BRUS project which ended in March, Dr. Brusatte and his team collected new fossils dating back to the first million years after the extinction, which is thought to have lasted about 60,000 years, and put together a family tree of early mammals.


They hunted for fossils in New Mexico, US, which is known to have the best record of vertebrate specimens from this period. They collected several new fossils, including the previously unknown Kimbetopsalis simmonsae, a beaver-like species that lived during the first few hundred thousand years after the extinction.


The team also visited museums to explore fossil collections, which allowed them to describe the features of several important mammal species in detail, such as a type of Periptychus, one of the first mammals to prosper after the asteroid struck.


The specimens that they analysed are also providing an insight into how mammals living right after the extinction are linked to modern ones.


‘Some of today’s familiar mammals, like the groups that later evolved into horses or bats, got their start soon after the extinction and probably as a direct result of it,’ Dr. Brusatte said.


Wiped out


The work supports a growing body of research showing that when the dinosaurs were wiped out, it wasn’t simply a case of one group of animals dying off and another taking over as was previously thought.











New clues unearthed about mammals' rapid evolution after dinosaur extinction
The beaver-like Kimbetopsalis simmonsae is one mammal species that lived during the first
few hundred thousand years after the dinosaurs died out [Credit: Sarah Shelley]

Smaller mammals seemed to be better equipped to survive since they could hide more easily, for example, and those with a diverse diet were able to adapt more quickly, Dr. Brusatte said.


‘There isn’t one magic reason why some of them lived and others died,’ he said. ‘There was probably chance and randomness involved because things changed so quickly after the asteroid hit.’


The team was surprised to learn how quickly mammals evolved after the extinction. Although the first mammals originated at the same time as the early dinosaurs – more than 200 million years ago – they remained small, about the size of badgers, when they co-existed.


A few hundred thousand years after dinosaurs disappeared, there were much larger, cow-sized species. ‘Mammals just took advantage of the opportunity and started to evolve really fast,’ Dr. Brusatte said.


How they dealt with changes in climate remains a mystery. After the asteroid hit, there were a few years of immediate cooling followed by a few thousand years of global warming where temperatures spiked by 5°C. Then, over the next 10 million years, temperatures dropped, although the baseline temperature was still much hotter than it is today.


In the future, Dr. Brusatte and his team want to find out how temperature variations affected mammals—whether they changed in size, expanded or retracted their range, and whether some species became extinct, for example.


‘We want to know these things to understand climate change in our world today,’ Dr. Brusatte said. ‘We just have to collect more fossils.’


But it wasn’t just dinosaur extinction that influenced the evolution and rise of mammals—other environmental factors could also have played an important role.


A shift in vegetation took place in the last 10 million years or so of the Cretaceous period when flowering plants, such as deciduous trees, started to become more commonplace than the previously widespread conifers and ferns. The animals’ habitat would have become more complex since deciduous trees have an elaborate canopy and understory.


‘Even if dinosaurs hadn’t become extinct, mammals would have prospered anyway because of the change in forest environments,’ said palaeontologist Professor Christine Janis from the University of Bristol in the UK.


Movement


Prof. Janis and her colleagues decided to investigate whether the change in plant life affected the habitat preferences of small mammals. As part of the MDKPAD project, which ran from 2015 until the end of 2017, they looked at mammal bones to deduce whether they lived in the ground or in trees as limb bones reflect locomotor behaviour.











New clues unearthed about mammals' rapid evolution after dinosaur extinction
Fossilised finger and toe bones from the Royal Tyrrell Museum of Paleontology in Canada have
helped determine the lifestyle of early mammals [Credit: Prof. Christine Janis]

Previous work had typically examined mammal teeth, which are prevalent in the fossil records, to gain insight into diets from that time. Studies looking at changes in mammals’ limbs were limited to a few complete skeletons so the team set out to see if scraps of skeletons could provide similar information.


Whole fossils of small mammals from that era are rare. So Prof. Janis used around 500 bone fragments that she found in museums in North America, where the best collections from the late Cretaceous are found.


But before she could start her analysis, she first had to understand existing mammals to figure out how the shape of different parts of their bones, mainly the articulation of their joints, relate to arboreal or terrestrial lifestyles.


‘You’ve got to have a comparative database,’ said Prof. Janis, who set out to create one. ‘That’s not something that existed.’


Prof. Janis has now collected details of the bones of about 100 small living mammals and catalogued them. She found that pieces of joints, which also happen to be preserved more often since they are more dense, can reveal a small animal’s mode of locomotion with a good degree of confidence.


Certain joints, like the elbow and knee, showed similar anatomical correlations to those of small living animals, so these could be used to identify the locomotive behaviour linked to a fossil.


Surprisingly, mammal bones from the last 10 million years of the Cretaceous period showed that most were generalised but a few very arboreal, with limbs similar to those of modern primates. ‘I was expecting all of the animals to be more like squirrels and not quite as specialised,’ Prof. Janis said.


The bones of extinct mammals suggest they became more terrestrial in the early Paleogene, the period after the Cretaceous. Prof. Janis thinks it’s because of an increase in understory vegetation. ‘Bushes and shrubs beneath the tree canopy were now a more suitable habitat for these small mammals,’ she said.


Although Prof. Janis does not plan to further the project, she will make her bone database available to other researchers. This database could help scientists determine the behaviour of individual species, locomotive changes in communities over time, and allow for local and global environmental changes to be tracked.


‘The powerful thing about this data is that you don’t need to have pristine skeletons (to do comparisons),’ she said. ‘You can have scrappy data and still get results from it.’


Author: Sandrine Ceurstemont | Source: Horizon: The EU Research & Innovation Magazine [August 27, 2018]



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How will humans adapt to climate change? Ask a Viking

Popular culture portrays Vikings as violent marauders who raided the coasts of Europe with impunity, but new research indicates the Vikings were vulnerable to at least one threat: a changing climate.











How will humans adapt to climate change? Ask a Viking
Open sea off the eastern shore of the island of Flakstadoya 
[Credit: Kevin Krajick]

William & Mary geologist Nick Balascio recently returned from Norway. He’s part of a team of climate scientists, archaeologists and students who are working to understand how environmental changes impacted Viking society during the Iron Age.


The research team, a collaboration among William & Mary, Columbia University, Tromsø University and the Lofotr Viking Museum, set its sights on the Lofoten Islands. The string of islands along the northern coast of Norway developed from small agricultural outposts to prominent Viking power centers during the Iron Age. The team plans to use biogeochemical markers left in lake sediment to chart environmental changes and reconstruct human activity patterns on the islands.


“In some of these coastal regions, you can see the Vikings were moving their harbors because of sea level change,” Balascio said. “Having access to a harbor was especially vital, because fishing was one of their main resources. If sea level change was affecting harbor access, the chieftains would have had to figure out a way to maintain trade and power.”


The Lofoten Islands are located above the Arctic Circle, which makes the region a particularly interesting case study for researching climate change, Balascio said. The Vikings were able to develop an agricultural settlement right at the edge of where agriculture was possible. The Vikings also relied on access to the ocean, as cod was one of their main trading commodities. Those two factors led Balascio to look for evidence of environmental fluctuations, because even the slightest change would have greatly affected Viking civilization.











How will humans adapt to climate change? Ask a Viking
Scientists are plumbing the bottoms of lakes and bays in Norway’s arctic Lofoten Islands to investigate the influence of
shifting climate and sea level on the Vikings. Climatologist William D’Andrea of Lamont-Doherty Earth Observatory
 hauls up a float that has been moored below the surface of a bay for several years [Credit: Kevin Krajick]

“Right near the end of the Viking Age, we’re still trying to pinpoint the exact chronology, you see the abandonment of all these Viking boathouses,” Balascio said. “Likely they were relocating to another part of the coast, because the sea level was lowering.”


Unlike sea level rise, which climate scientists see as a major threat today, the Lofoten Islands were experiencing a relative drop in sea level. As glacial ice melted, its weight was lifted from the land, causing the Earth’s crust to rise. In fact, the land was rising so fast entire Viking chiefdoms were left without a way to access the ocean, Balascio explained. Ports became landlocked, because the harbor had literally risen out of the sea.


Due to the particular geology of the region, changes in climate caused the relative sea level to fall over the past 10,000 years, Balascio said. It’s not that the water was drying up, it’s that the land was heightened. Glaciers once made up a large amount of the arctic landmass. As they melted, the pressure removed from the Earth’s crust caused the land beneath it to rise.


Picture getting up from a mattress after lying down. The indentation left by your body will rise until the mattress gets back into its original form. Though much of the arctic ice melted long ago, the land it once covered is still rebounding from its ice-age burden. This ongoing adjustment of the Earth’s crust is called glacial isostatic adjustment.











How will humans adapt to climate change? Ask a Viking
The islands’ unforgiving weather and landscape have always forced people to make a living from both land and sea.
Tromso University Museum archaeologist Stephen Wickler (left) and Northern Arizona University palynologist
Scott Anderson survey a coastal landscape occupied by predecessors of the Vikings some 6,000 years ago
[Credit: Kevin Krajick]

“The land surface has been rebounding over the last few thousand years since the ice left,” Balascio said. “Most Viking Age boathouses are at least two meters above present sea level, because the sea level was actually falling. It’s not necessarily the same thing that’s happening today, but it is a clear example of how sea level change had an influence on a civilization.”


Balascio took his first research trip to Norway as a Ph.D. student in 2007. For the better part of the past decade, he has wanted to return and build on his early work there. Last year, he received funding from the National Science Foundation to go back to Norway. His current research is primarily focused on using biomarkers in lake sediments to chart environmental and societal changes during the Iron Age (c. 500 BC-AD 1100).


“A main objective is to test the hypothesis that climate variability and sea-level variations had an impact on patterns of human settlement,” he said.


The team began fieldwork last year, with two undergraduate geology students Moussa Dia ’18 and Eve Pugsley ’18 coming along to help collect samples. This summer, on a return trip, Leah Marshall ‘19 joined the field crew. The experience was hardly a vacation.


“We work on these little, inflatable rafts to collect lake sediment,” Balascio said. “It’s exciting, but it’s also really uncomfortable.”



Lofoten island lakes were created by glaciers, Balascio explained, which means they are extremely deep – anywhere from 60 to 150 feet. While they are lakes today, they were once harbors that led to out to the ocean. The sediment the lakes contain holds the key to understanding that transition. The field crew is responsible for coring the lakes, taking long tubes of sediment from the lake floor. The core tubes are lowered over the sides of inflatable rafts with ropes, filled with sediment and hoisted back up from the depths.


“That’s the most challenging thing, just working on lakes that are that deep,” Balascio said. “We have to recover the cores intact and we’re not on big vessels. We’re on these tiny rafts.”


Back in the lab at William & Mary, Balascio’s students Dia, Pugsley and Marshall have helped analyze the samples to try to piece together a historical record where one doesn’t exist. Much of what remains of Viking history was passed down through folklore, Balascio said, so his students are using geochemical analysis to try to build an environmental and archeological narrative. 


“We’re analyzing sediments, trying to provide chronologic information and context through radiocarbon dating,” Balascio said. “When you go back in time, the records get more scarce. You are limited in the information you have, because there are no written records.”


The sediment analysis is still in its early stages and Balascio expects it to be at least another year before he has a clear picture of how the Vikings responded to climate change. Even at this nascent stage, Balascio says he is already starting to get a sense of how people lived in one of the harshest environments on Earth.


“It’s a good reminder that people have been responding to and adapting to climate change for a long time,” Balascio said. “It’s not something that’s necessarily new or happened in the last 150 years with global warming. This is something that civilizations have dealt with for a very long time.”


Author: Adrienne Berard | Source: The College of William & Mary [August 27, 2018]



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Team digitizes historic sanctuary of Machu Picchu

For many people, the Inca city of Machu Picchu in the Andes of Peru is one of the most recognizable icons of archaeological and adventure tourism in the world. However, for the Peruvian people and for the international scientific community, Machu Picchu is much more than a tourist destination. In addition to being a United Nations Educational, Scientific and Cultural Organization (UNESCO) World Heritage Site, the historic sanctuary has great cultural and economic importance for Peru and the region of Cusco.











Team digitizes historic sanctuary of Machu Picchu
View of Machu Picchu [Credit: Inca Explorer/STA Travel]

The first references to attempts to document the city of Machu Picchu date back to the late 19th century, when Peruvian and European explorers toured the rugged mountains around the meandering Urubamba River. Some of the explorers did not hesitate to register their visit in the rock. On a wall of the Temple of the Three Windows, Agustin Lizarraga recorded, “July 14, 1902”.


But it was Yale University Professor Hiram Bingham who extensively documented the site during his expedition in 1911, and made known to the international community the existence of the lost ruins of the Incas. Over the last 100 years, dozens of archaeological expeditions have contributed to increasing the architectural value and interest in the site, as well as the scientific knowledge of the extraordinary technologies developed by the Incas.


In order to digitally document and develop the foundations for future research, a laboratory team from the MIT Department of Architecture, led by Professor Takehiko Nagakura and PhD student Paloma Gonzales, has been working on the MISTI Global Seed Fund Machu Picchu Design Heritage project since 2016.


The team, the Architecture Representation and Computation Group, has led the first extensive expedition to digitally document Machu Picchu, using the latest generation of instruments and techniques to explore the site’s architectural and urban importance  and develop a 3-D site map using virtual reality and augmented reality. The Architecture Representation and Computation Group has an important record of working with digital capturing technologies on World Heritage Sites in Italy, China, Singapore, and Japan.











Team digitizes historic sanctuary of Machu Picchu
A 3-D model, like this sample, will allow people to explore Machu Picchu through virtual
and augmented reality [Credit: MISTI]

“We believe that documentation through computational techniques for the digitalization of architectural monuments is key to the preservation of the cultural heritage of humanity,” Nagakura says. “But it is just a simple idea for old practice. From Renaissance time, architects have been going to building sites, and drawing them up to study them. We are just replacing tape measures and Mylar sheets with scanning tools and VR headsets.”


For the project in Peru, the team visited the archaeological complex on two occasions for several weeks in mid-2017 and early 2018. At the site, more than 9,000 images were collected through panoramic cameras, photogrammetric scanning tools, and drones. Gonzales says the working hours were “intense.”


“We had to reach the archaeological monument before the arrival of the tourists and stay after the closure of the monument,” she says. “The great commitment and joint work of the MIT team and the San Antonio Abad del Cusco University, supported by the Decentralized Directorate of Culture of Cusco, made the work fruitful and rewarding.”


Based on the photogrammetric data they sampled, the team developed 3-D models and are working on creating virtual reality experiences that would allow people to immerse themselves in Machu Picchu from anywhere on the planet. The same 3-D models are also being deployed to make a new interactive map of Machu Picchu that superimposes the photographic 3-D view of the site through augmented reality.


Last December, the team launched the MIT Design Heritage Platform, where visitors can see and explore part of the work they have done. In addition, they plan to make this platform a tool to collect images from those who can contribute to the data bank through crowdsourcing.











Team digitizes historic sanctuary of Machu Picchu
Posing with a panoramic view of Machu Picchu in Peru are (l-r) PhD student Paloma Gonzalez,
Associate Professor Takehiko Nagakura, and two MIT graduate students [Credit: MISTI]

The project has also managed to document the architectural characteristics and construction materials of the city with high-resolution photographic techniques. The images constitute a unique database with rich information on aspects such as landscape and vegetation at the time the photographs were taken. The team will make all of the information collected available to the authorities of the archaeological monument.


At the same time, they expect that other disciplines can use the databases and photogrammetric models they are developing. The documentation has already been used in conservation efforts, including in the reconstruction of Wiñay Wayna, an archeological site located on the Inca Trail leading to Machu Picchu that was destroyed by a recent flood storm.


Fernando Astete, anthropologist and head of the National Archaeological Park of Machu Picchu, says: “We are very excited with the MIT team work. We welcome all efforts to research and preserve Machu Picchu. We have to protect our heritage for the next generations.”


Architect Cesar Medina, responsible for the digitization of the national park, believes that the collaboration with MIT has been enriching.


“We have been working in 3-D documentation since 2013, but the collaboration with the MIT team lead by Professor Nagakura, with the support of our local university, has allowed us to exhaustively document Machu Picchu, making use of the latest technologies and innovative techniques,” Medina says. “Moreover, we have had the opportunity to visit and know the work of his lab; we see with great interest to continue working in the future with MIT.”


The Architecture Representation and Computation Group is already in conversation with institutions of higher education and heritage conservation of Peru to continue advancing the project of digital inheritance. In addition to continuing in Machu Picchu, they may extend the documentation areas to other archaeological sites of Peru. The project has also opened the doors to possible interdisciplinary collaborations with materials science researchers, urban planners, hydrologist, engineers, archaeologists, and historians.


Author: Eduardo Rivera | Source: Massachusetts Institute of Technology [August 28, 2018]



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Eastern European woolly mammoths changed their diet with fatal consequences

Senckenberg scientists, together with an international team, studied the potential cause of extinction of the Woolly Mammoth 18,000 years ago. In their study, recently published in the scientific journal Quaternary Research, they concluded on the basis of isotope analyses that the mammoths had to change their feeding habits shortly before becoming extinct. This forced environmental adaptation, combined with hunting pressure from early humans, ultimately led to the mammoths’ demise.











Eastern European woolly mammoths changed their diet with fatal consequences
The fossilized bones from the Yudinovo fossil site offer insights into the woolly mammoth’s diet
[Credit: Mietje Germonpré]

Woolly Mammoths (Mammuthus primigenius) developed around 800,000 to 600,000 years ago and are considered the final representatives of the mammoth clan. But even these last surviving relatives of the elephants disappeared from large parts of their range approx. 15,000 years ago.


“With the death of the last relic population on Wrangel Island, the extinction of the Woolly Mammoth became final,” explains Dr. Dorothée Drucker of the Senckenberg Centre for Human Evolution and Palaeoenvironment (HEP) at the Eberhard Karls University in Tübingen, and she continues, “Whether excessive hunting pressure or rapid climate change toward the end of the Ice Age caused the animals to go extinct is still a matter of contention.”


Searching for an answer, an international team headed by Drucker and joined by Senckenberg scientist Prof. Dr. Hervé Bocherens examined the carbon and nitrogen isotope composition of 18,000 to 17,000-year-old fossil mammoth bones. Both elements are found in the animals’ bone collagen and offer insights into the type of plants that constituted the mammoths’ primary diet.


“Earlier studies revealed that the mammoths primarily fed on steppe grasses across their entire range – from Southwestern France to Alaska. Thus, their diet clearly differed from that of other herbivores such as woolly rhinoceroses, horses, bison or reindeer, and the mammoths occupied their own ecological niche,” explains Drucker.











Eastern European woolly mammoths changed their diet with fatal consequences
Samples from mammoths in the Ukraininan region around Mezhirich show low nitrogen isotope values
– an indication of the dietary change [Credit: Mietje Germonpré]

Therefore, the scientist from Tübingen was even more surprised to find that the samples from mammoths discovered in the Ukrainian region around Mezhirich showed low nitrogen isotope values.
“Such values are usually only known from equine bones,” adds Drucker.


The team of scientists concluded that the mammoths were forced to change their diet about 3,000 years prior to their extinction, since they were no longer able to find their previous food due to the climate change.


Drucker elaborates: “The mammoths were now forced to compete for food with other herbivores, and the alternative diet proved less than optimal for the large animals. Moreover, their attempts to adjust to the changing environmental conditions were further impeded by the hunting pressure from humans.”


In conclusion, Drucker’s team of scientists postulates that the mammoths of Mezhirich became extinct because of the climate change and the associated environmental changes. “We still need to study whether this was also the case in other mammoth populations,” says Drucker, and she offers the following outlook: “Our data can provide important information regarding the mechanisms of extinction in large mammals against the background of climate change and the competition with humans. Unfortunately, this same situation still affects many animals today.”


Source: Senckenberg Research Institute and Natural History Museum [August 29, 2018]



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