среда, 14 ноября 2018 г.

Extended life for ESA’s science missions


ESA – European Space Agency patch.


14 November 2018


ESA’s Science Programme Committee (SPC) has confirmed the continued operations of ten scientific missions in the Agency’s fleet up to 2022.


After a comprehensive review of their scientific merits and technical status, the SPC has decided to extend the operation of the five missions led by ESA’s Science Programme: Cluster, Gaia, INTEGRAL, Mars Express, and XMM-Newton. The SPC also confirmed the Agency’s contributions to the extended operations of Hinode, Hubble, IRIS, SOHO, and ExoMars TGO.


This includes the confirmation of operations for the 2019–2020 cycle for missions that had been given indicative extensions as part of the previous extension process, and indicative extensions for an additional two years, up to 2022 [1].


The decision was taken during the SPC meeting at ESA’s European Space Astronomy Centre near Madrid, Spain, on 14 November.


ESA’s science missions have unique capabilities and are prolific in their scientific output. Cluster, for example, is the only mission that, by varying the separation between its four spacecraft, allows multipoint measurements of the magnetosphere in different regions and at different scales, while Gaia is performing the most precise astrometric survey ever realised, enabling unprecedented studies of the distribution and motions of stars in the Milky Way and beyond.



ESA fleet in the Solar System

Many of the science missions are proving to be of great value to pursue investigations that were not foreseen at the time of their launch. Examples include the role of INTEGRAL and XMM-Newton in the follow-up of recent gravitational wave detections, paving the way for the future of multi-messenger astronomy, and the many discoveries of diverse exoplanets by Hubble.


Collaboration between missions, including those led by partner agencies, is also of great importance. The interplay between solar missions like Hinode, IRIS and SOHO provides an extensive suite of complementary instruments to study our Sun; meanwhile, Mars Express and ExoMars TGO are at the forefront of the international fleet investigating the Red Planet.


Another compelling factor to support the extension is the introduction of new modes of operation to accommodate the evolving needs of the scientific community, as well as new opportunities for scientists to get involved with the missions.


[1] Every two years, all missions whose approved operations end within the following four years are subject to review by the advisory structure of the Science Directorate. Extensions are granted to missions that satisfy the established criteria for operational status and science return, subject to the level of financial resources available in the science programme. These extensions are valid for the following four years, subject to a mid-term review and confirmation after two years.


Related links:


ESA’s Cluster: http://sci.esa.int/cluster


ESa’s Gaia: http://sci.esa.int/gaia


ESA’s INTEGRAL: http://sci.esa.int/integral


ESA’s Mars Express: http://sci.esa.int/mars-express


ESA’s XMM-Newton: http://sci.esa.int/xmm-newton


ESA’s collaboration:


ESA’s Hinode: http://www.isas.jaxa.jp/en/missions/spacecraft/current/hinode.html


ESA’s Hubble: http://sci.esa.int/hubble


ESA’s IRIS: https://www.nasa.gov/mission_pages/iris/index.html


ESA’s SOHO: http://sci.esa.int/soho


ESA’s ExoMars TGO: http://exploration.esa.int/mars


Image, Text, Credits: ESA/Luigi Colangeli.


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Holocene temperature in the Iberian Peninsula reconstructed…


Holocene temperature in the Iberian Peninsula reconstructed studying insect subfossils http://www.geologypage.com/2018/11/holocene-temperature-in-the-iberian-peninsula-reconstructed-studying-insect-subfossils.html


Most complete study on Europe’s greatest Hadrosaur site…


Most complete study on Europe’s greatest Hadrosaur site published http://www.geologypage.com/2018/11/most-complete-study-on-europes-greatest-hadrosaur-site-published.html


Rare fossil bird deepens mystery of avian extinctions…


Rare fossil bird deepens mystery of avian extinctions http://www.geologypage.com/2018/11/rare-fossil-bird-deepens-mystery-of-avian-extinctions.html


Ancient flower fossil points to core eudicot boom 99 million…


Ancient flower fossil points to core eudicot boom 99 million years ago http://www.geologypage.com/2018/11/ancient-flower-fossil-points-to-core-eudicot-boom-99-million-years-ago.html


2018 November 14 The Cave Nebula in Hydrogen, Oxygen, and…


2018 November 14


The Cave Nebula in Hydrogen, Oxygen, and Sulfur
Image Credit & Copyright: Chuck Ayoub


Explanation: What’s inside this cosmic cave? A stellar nursery 10 light-years deep. The featured skyscape is dominated by dusty Sh2-155, the Cave Nebula. In the telescopic image, data taken through a narrowband filters tracks the nebular glow of hydrogen, oxygen, and sulfur, colors that together form the Hubble Palette. About 2,400 light-years away, the scene lies along the plane of our Milky Way Galaxy toward the royal northern constellation of Cepheus. Astronomical explorations of the region reveal that it has formed at the boundary of the massive Cepheus B molecular cloud and the hot, young stars of the Cepheus OB 3 association. The bright rim of ionized hydrogen gas is energized by radiation from the hot stars, dominated by the bright star just to the left of the cave entrance. Radiation driven ionization fronts are likely triggering collapsing cores and new star formation within.


∞ Source: apod.nasa.gov/apod/ap181114.html


Tourmaline | #Geology #GeologyPage #Mineral Locality: Veadinho…


Tourmaline | #Geology #GeologyPage #Mineral


Locality: Veadinho claims, Marilac, Minas Gerais, Brazil


Size: 5.3 x 2.3 x 1.4


Photo Copyright © Saphira Minerals


Geology Page

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Fluorite and Quartz | #Geology #GeologyPage #Mineral Locality:…


Fluorite and Quartz | #Geology #GeologyPage #Mineral


Locality: Yaogangxian Mine, Yizhang Co., Chenzhou Prefecture, Hunan Province, China


Size: 4.5 x 4.1 x 3


Photo Copyright © Saphira Minerals


Geology Page

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https://www.instagram.com/p/BqJm896FFNQ/?utm_source=ig_tumblr_share&igshid=llwgkyn36blu


Baryte with Calcite | #Geology #GeologyPage Locality:…


Baryte with Calcite | #Geology #GeologyPage


Locality: Gyongyosoroszi, Matra Mts, Heves Co, Hungary, Europe


Dimensions: 6.0 × 3.2 × 2.5 cm


Photo Copyright © Crystal Classics


Geology Page

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https://www.instagram.com/p/BqJnK1zFb5V/?utm_source=ig_tumblr_share&igshid=lkj59ccfzfs0


Baryte | #Geology #GeologyPage #Mineral Locality: Clara Mine,…


Baryte | #Geology #GeologyPage #Mineral


Locality: Clara Mine, Oberwolfach, Black Forest, Germany, Europe


Dimensions: 5.4 × 4.6 × 4.0 cm


Photo Copyright © Crystal Classics


Geology Page

www.geologypage.com

https://www.instagram.com/p/BqJnPUylanB/?utm_source=ig_tumblr_share&igshid=gsirjtvaql99


Primates of the Caribbean: Ancient DNA reveals history of…


Primates of the Caribbean: Ancient DNA reveals history of mystery monkey http://www.geologypage.com/2018/11/primates-of-the-caribbean-ancient-dna-reveals-history-of-mystery-monkey.html


Spacetime: a creation of well-known actors?

Most physicists believe that the structure of spacetime is formed in an unknown way in the vicinity of the Planck scale, i.e. at distances close to one trillionth of a trillionth of a metre. However, careful considerations undermine the unambiguity of this prediction. There are quite a few arguments in favour of the fact that the emergence of spacetime may occur as a result of processes taking place much “closer” to our reality: at the level of quarks and their conglomerates.











Spacetime -- a creation of well-known actors?
Just as the interactions between sand grains form a smooth surface on the beach, the spacetime known
to us could be the result of relations between quarks and their conglomerates [Credit: IFJ PAN]

What is spacetime? The absolute, unchanging, ever- and omni-present arena of events? Or perhaps it is a dynamic creation, emerging in some way on a certain scale of distance, time or energy? References to the absolute are not welcome in today’s physics. It is widely believed that spacetime is emergent. It is not clear, however, where the process of its emergence takes place. The majority of physicists tend to suppose that spacetime is created on the Planck scale, at distances close to one trillionth of a trillionth of a metre (~10-35 m). In his article in Foundations of Science, Professor Piotr Zenczykowski from the Institute of Nuclear Physics of the Polish Academy of Sciences (IFJ PAN) in Cracow systematizes the observations of various authors on the formation of spacetime, and argues that the hypothesis about its formation at the scale of quarks and hadrons (or quark aggregates) is quite sensible for a number of reasons.
Questions about the nature of space and time have puzzled humanity since at least antiquity. Are space and time separated from matter, creating a “container” for motions and events occurring with the participation of particles, as Democrit proposed in the 5th century BC? Or perhaps they are attributes of matter and could not exist without it, as Aristotle suggested a century later? Despite the passage of millennia, these issues have not been resolved yet. Moreover, both approaches – albeit so contradictory! – are deeply ingrained into the pillars of modern physics. In quantum mechanics, events take place in a rigid arena with uniformly flowing time. Meanwhile, in the general theory of relativity, matter deforms elastic spacetime (stretching and twisting it), and spacetime tells particles how to move. In other words, in one theory the actors enter an already prepared stage to play their roles, while in the other they create the scenography during the performance, which in turn influences their behaviour.


In 1899, German physicist Max Planck noticed that with certain combinations of some constants of nature, very fundamental units of measurement could be obtained. Only three constants – the speed of light c, the gravitational constant G and Planck’s constant h – were sufficient to create units of distance, time and mass, equal (respectively) to 1.62 · 10-35 m, 5.39 · 10-44 s and 2.18 · 10-5 g. According to today’s mainstream belief, spacetime would be created at Planck’s length. In fact, there are no substantive arguments for the rationality of this hypothesis.


Both our most sophisticated experiments and theoretical descriptions reach the scale of quarks, i.e. the level of 10-18 m. So how do we know that along the way to Planck’s length – over a dozen consecutive, ever smaller orders of magnitude – spacetime retains its structure? In fact, we are not even sure if the concept of spacetime is rational at the level of hadrons! Divisions cannot be carried out indefinitely, because at some stage the question of the next smaller part simply ceases to make sense. A perfect example here is temperature. This concept works very well on a macro scale, but when, after subsequent divisions of matter, we reach the scale of individual particles, it loses its raison d’etre.


“At present, we first seek to construct a quantized, discrete spacetime, and then ‘populate’ it with discrete matter. However, if spacetime was a product of quarks and hadrons, the dependence would be reversed: the discrete character of matter should then enforce the discreteness of spacetime!” says Prof. Zenczykowski, and adds: “Planck was guided by mathematics. He wanted to create units from the fewest constants possible. But mathematics is one thing, and the relationship with the real world is another. For example, the value of Planck’s mass seems suspicious. One would expect it to have a value rather more characteristic for the world of quanta. In the meantime, it corresponds to approximately 1/10 of the mass of a flea, which is most certainly a classical object.”


Since we want to describe the physical world, we should lean towards physical rather than mathematical arguments. And so, when using Einstein’s equations we describe the Universe at large scales, and it becomes necessary to introduce an additional gravitational constant, known as the cosmological constant Lambda. If, therefore, while constructing fundamental units, we expand the original set of three constants by Lambda, in the case of masses we obtain not one but three fundamental values: 1.39 · 10-65 g, 2.14 · 1056 g, and 0.35 · 10-24 g. The first of these could be interpreted as a quantum of mass, the second is at the level of the mass of the observable Universe, and the third is similar to the masses of hadrons (for example, the mass of a neutron is 1.67 · 10-24 g). Similarly, after taking Lambda into account, a unit of distance of 6.37 · 10-15 m appears, very close to the size of hadrons.


“Playing games with constants, however, can be risky because a lot depends on which constants we choose. For example, if spacetime was indeed a product of quarks and hadrons, then its properties, including the velocity of light, should also be emergent. This in turn means that the velocity of light should not be among the basic constants,” notices Prof. Zenczykowski.


Another factor in favour of the formation of spacetime at the scale of quarks and hadrons are the properties of the elementary particles themselves. For example, the Standard Model does not explain why there are three generations of particles, where their masses come from, or why there are so-called internal quantum numbers, which include isospin, hypercharge and colour. In the picture presented by Prof. Zenczykowski these values can be linked to a certain six-dimensional space created by the positions of particles and their momenta. The space thus constructed assigns the same importance to the positions of particles (matter) and their movements (processes). It turns out that the properties of masses or internal quantum numbers can then be a consequence of the algebraic properties of 6D space. What’s more, these properties would also explain the inability to observe free quarks.


“The emergence of spacetime may be associated with changes in the organization of matter occurring at a scale of quarks and hadrons in the more primary, six-dimensional phase space. However, it is not very clear what to do next with this picture. Each subsequent step would require going beyond what we know. And we do not even know the rules of the game that Nature is playing with us, we still have to guess them! However, it seems very reasonable that all constructions begin with matter, because it is something physical and experimentally available. In this approach, spacetime would only be our idealization of relations among elements of matter,” sums up Prof. Zenczykowski.


Source: The Henryk Niewodniczanski Institute of Nuclear Physics [November 09, 2018]



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Hubble Spots a Lonely Blue Dwarf


NASA – Hubble Space Telescope patch.


Nov. 13, 2018



This captivating image from the NASA/ESA Hubble Space Telescope’s Wide Field Camera 3 shows a lonely dwarf galaxy 100 million light-years away from Earth. This image depicts the blue compact dwarf galaxy ESO 338-4, which can be found in the constellation of Corona Australis (the Southern Crown).


Blue compact dwarf galaxies take their name from the intensely blue star-forming regions that are often found within their cores. One such region can be seen embedded in ESO 338-4, which is populated with bright, young stars voraciously consuming hydrogen. These massive stars are doomed to a short existence, despite their vast supplies of hydrogen fuel. The nuclear reactions in the cores of these stars will burn through these supplies in only millions of years — a mere blink of an eye in astronomical terms.


The young, blue stars nestled within a cloud of dust and gas in the center of this image are the result of a recent galaxy merger between a wandering galaxy and ESO 388-4. This galactic interaction disrupted the clouds of gas and dust surrounding ESO 338-4 and led to the rapid formation of a new population of stars.



Hubble Space Telescope (HST)

For more information about Hubble, visit:


http://hubblesite.org/
http://www.nasa.gov/hubble
http://www.spacetelescope.org/


Image, Animation, Text, Credits: ESA/Hubble & NASA/Text credit: European Space Agency (ESA)/NASA/Karl Hille.


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U.S., Russian Rockets Preparing to Resupply Station This Weekend


ISS – Expedition 57 Mission patch.


November 13, 2018


A U.S. rocket stands at its launch pad at the Wallops Flight Facility in Virginia counting down to a Thursday morning launch. On the other side of the world in Kazakhstan, a Russian rocket is being processed for its launch Friday afternoon. Both spaceships are hauling several tons of food, fuel, supplies and new science to resupply the Expedition 57 crew aboard the International Space Station.


First, Northrop Grumman’s Cygnus space freighter is set to blastoff atop the Antares rocket Thursday at 4:49 a.m. EST from Virginia’s Atlantic coast. Next, Russia will roll out its Progress 71 (71P) cargo craft for a launch Friday at 1:14 p.m. from the Baikonur Cosmodrome.



Image above: Northrop Grumman’s Antares rocket carrying a Cygnus resupply spacecraft is seen on Pad-0A after being raised into a vertical position, Tuesday, Nov. 13, 2018 at NASA’s Wallops Flight Facility in Virginia. Image Credit: NASA.


Cygnus will then lead the 71P on a dual journey to the orbital laboratory where the two spaceships will arrive on Sunday just hours apart. Cygnus will get there first when Commander Alexander Gerst assisted by Flight Engineer Serena Auñón-Chancellor captures the private cargo carrier at 4:35 a.m. with the Canadarm2 robotic arm. After some rest, cosmonaut Sergey Prokopyev will monitor the automated docking of the 71P to the Zvezda service module’s rear port at 2:30 p.m.



Image above: The Russian Progress 60 cargo craft is seen shortly after undocking from the Space Station, Dec. 19, 2005. The unpiloted Russian Progress 71 cargo ship is scheduled to launch Friday, Nov. 16, to the orbiting laboratory, bringing food, fuel and supplies to the crew. Image Credit: NASA.


Gerst and Serena trained today for the robotic capture of Cygnus on Sunday reviewing approach and rendezvous procedures. Gerst first started his day reviewing details about a new free-flying robotic assistant that uses artificial intelligence before moving on to protein crystal research. Serena worked on the Life Sciences Glovebox then moved on to orbital plumbing tasks.


The duo also joined Prokopyev for ongoing eye checks in conjunction with doctors on the ground. Prokopyev primarily worked in the Russian segment throughout Tuesday on life support maintenance and science experiments.


Related links:


NASA TV: https://www.nasa.gov/nasatv


Expedition 57: https://www.nasa.gov/mission_pages/station/expeditions/expedition57/index.html


Free-flying robotic assistant: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7639


Protein crystal research: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7741


Life Sciences Glovebox: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=7676


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.


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The secret behind coral reef diversity? Time, lots of time

Strap on a diving mask and fins and slip under the crystal-clear water near a coral reef in Indonesia, Papua-New Guinea or the Philippines, and you’ll immediately see why divers and snorkelers from across the world flock to the area. Known as the Coral Triangle, the region is famous for its unmatched diversity of reef fish and other marine creatures.











The secret behind coral reef diversity? Time, lots of time
Until now, researchers had a hard time explaining why the Coral Triangle in the Central-Indo Pacific
 is the world’s leading spot of marine biodiversity [Credit: GreensMPs/Flickr]

Fish of all shapes and colors dart in and out of crevices created by the dazzling shapes of corals, colorful sponges and other reef-building organisms. With a little luck, a diver might catch a glimpse of a shark patrolling the reef or a turtle soaring across the landscape of colors.


While underwater enthusiasts have long known and cherished the biodiversity in the Central-Indo Pacific Ocean, scientists have struggled for more than half a century to explain what exactly makes the region the world’s No. 1 hot spot of marine biodiversity and sets it apart from other marine regions around the world.


Several hypotheses have been put forth to explain the Central-Indo Pacific region’s extraordinary diversity. Some researchers suggested species emerge at a faster rate there compared to other parts of the world’s oceans, while others attributed it to the region’s central location between several species-rich swaths of ocean in the broader Indo-West Pacific. Still others pointed to the region’s low extinction rates.


Now, a study led by University of Arizona doctoral student Elizabeth Miller has revealed that Indo-Pacific coral reefs have accumulated their unrivaled richness of fish species not because of some unknown, elusive quality, but simply because they had the time.


“People used to think that new species evolve more quickly in tropical marine areas, so you get the high diversity we see today very quickly,” Miller said. “Instead, we found that diversity in the Central-Indo Pacific has slowly built over a long time.”


The study, published in the journal Proceedings of the Royal Society of London, is the first to show a direct link between time and species richness, according to Miller.


Until now, Miller explained, it was widely believed that tropical coral reefs, similar to tropical rain forests, are hot spots of biodiversity because of an intrinsic propensity to diversify into more species than other regions. Her research showed that wasn’t the case.











The secret behind coral reef diversity? Time, lots of time
A clownfish seeks shelter in its sea anemone home in the Great Barrier Reef, which is part of this study
 [Credit: Deborah Shelton]

The team discovered that speciation rates are actually higher in cold marine areas such as the Arctic and Antarctic. However, while changes in biodiversity in the Central-Indo Pacific region could be compared to a slow but long-burning flame, in colder ocean regions, they are more like fireworks.


“There, species evolve relatively quickly, but each glaciation period clears out much of what was there before,” Miller said. “Once the glaciers recede, they leave empty niches waiting to be repopulated by new species.”


Frequent environmental upheaval results in overall biodiversity being lower in colder ocean regions.


In the Coral Triangle, on the other hand, new species have evolved less rapidly, but because conditions have been much more stable over long periods of geological time, they were more likely to stick around once they appeared and slowly accumulate to the biological diversity we see today.


“This suggests that a region may need long-term stability to accumulate high species diversity,” Miller said. “According to our study, the magic number appears to be 30 million years.”


In the Central-Indo Pacific, plate tectonics created a wide platform of shallow ocean, while its central location made it a target for colonization. It was the right place at the right time for the fishes that colonized the region.


“Things haven’t changed much there in the past 30 to 35 million years,” Miller said. “In contrast, other marine regions, such as the Caribbean, underwent periods of instability and isolation, and therefore fewer colonizations and higher rates extinction of the lineages that were there previously – all those factors add up to less evolutionary time.”


For the study, Miller and her team used distribution data of almost all spiny ray-finned fishes – 17,453 species in total, representing about 72 percent of all marine fishes and about 33 percent of all freshwater fishes. They used several different statistical methods to reconstruct the causes of underlying species richness patterns among global marine regions.


To disentangle how marine fish diversity unfolded over time, the team then used a published evolutionary tree of this fish group and performed biogeographic reconstructions.


“Biogeographic reconstructions help us understand where ancestors were living at various places back in time, based on where species live today and how they are related,” Miller said. “It’s easy if you only compare two species that live in the same place, but if you have thousands of species and go back further and further in time, more ancestors come into play and things become more difficult.”


Evolutionary biologists rely on sophisticated computer algorithms to manage and interpret the extremely large data sets. The method used by Miller and her team created many hypothetical scenarios of where species evolved. The researchers then used these scenarios to test how different models explain today’s biodiversity.


“It’s like drawing family histories, each slightly different,” Miller said. “You start out with analyses and repeat them hundreds of times, each time based on some possible history to try and encompass uncertainty to see how they play out. In our study, it turned out the uncertainty is low, which is reassuring. It means it’s a really robust result.”


The general idea that patterns of diversity can be explained by how long a group has been present rather than how quickly they proliferate is relevant to lots of different systems, according to the researchers. For example, biologists have observed that the timing of colonization explains the high diversity of certain animal groups in terrestrial ecosystems, such as treefrogs in the Amazon rainforests, salamanders in the Appalachian Mountains and lizards in the desert Southwest.


“The general takeaway is that these patterns of high diversity may take tens of millions of years to arise, but can be wiped out in a few years by human impacts,” said John Wiens, senior author of the paper and a professor in the UA Department of Ecology and Evolutionary Biology. “Unfortunately, the high diversity of reef fish in the Coral Triangle may soon disappear because of the impacts of human-induced climate change on coral reefs. The diversity that gets lost in the next few years may take tens of millions of years to get back.”


Source: University of Arizona [November 09, 2018]



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Stripping the linchpins from the life-making machine reaffirms its seminal evolution

So audacious was Marcus Bray’s experiment that even he feared it would fail. In the system inside cells that translates genetic code into life, he replaced about 1,000 essential linchpins with primitive substitutes to see if the translational system would survive and function. It seemed impossible, yet it worked swimmingly, and Bray had compelling evidence that the great builder of proteins was active in the harsh conditions in which it evolved 4 billion years ago.











Stripping the linchpins from the life-making machine reaffirms its seminal evolution
The ribosome (upper middle) is the core of the translational system illustrated here. The system reads DNA
via RNA and turns it into proteins to make all beings live [Credit: National Science Foundation]

The experiment’s success reaffirmed the translational system’s place at the earliest foundations of life on Earth.
Every living thing exists because the translational system receives messages from DNA delivered to it by RNA and translates the messages into proteins. The system centers on a cellular machine called the ribosome, which is made of multiple large molecules of RNA and protein and is ubiquitous in life as we know it.


“There’s nothing alive without ribosomes,” said Loren Williams, a professor at the Georgia Institute of Technology’s School of Chemistry and Biochemistry. “The ribosome is about the oldest and most universal part of biology, and its origins go very far back to a time not too long after Earth had formed and cooled.”


Eat your magnesium


Those linchpins Bray yanked out and replaced were metal ions (atoms with charges, in this case positive).


In today’s ribosome, and in the whole translational system, they are magnesium ions, and Bray’s experiment replaced them all with iron ions and manganese ions, which were overabundant on primordial Earth. Williams and Jennifer Glass, the principal investigators in the new study, also had their doubts this was doable.


“I thought, ‘It’s not going to work, but we might as well try the moonshot’,” said Williams who has led similar work before but on simpler molecules. “The fact that swapping out all the magnesium in the translational system actually worked was mind-boggling.”


That’s because in living systems today, magnesium helps shape ribosomes by holding them together. Magnesium is also needed for some 20 additional enzymes of the translational system. It’s one reason why dietary magnesium (Mg) is so important.


“The number of different things magnesium does in the ribosome and in the translational system is just enormous,” said Williams. “There are so many types of catalytic activities in translation, and magnesium is involved in almost all of them.”


Lava-belching Earth


When first life evolved, fissures in Earth’s crust still belched lava and meteor impacts were still common. There was no breathable oxygen and the planet was brimming with iron and manganese.


This may have made them attractive for the translational system to use as the dominant ions. Magnesium was likely involved, too, though it was probably less available than today.











Stripping the linchpins from the life-making machine reaffirms its seminal evolution
Marcus Bray, front, observes a sample inside a sealed atmospheric tent that has no breathable oxygen. The tent simulates
atmospheric gas mixtures during Earth’s earliest eon and allows researchers to work with samples by slipping their
 hands into leak-proof gloves. In the background, co-principal investigator and NASA astrobiologist
Loren Williams looks on in his lab at Georgia Tech [Credit: Georgia Tech/Allison Carter]

The researchers wanted to know if the translational system first evolved to function with those other metals as their linchpins. So, Bray, a graduate research assistant in Williams’s and in Glass’s lab, swapped out the magnesium ions for them, tabula rasa.


“We didn’t have any substantial reason to believe it would work, and it was a huge surprise to all of us when it did,” Bray said. And it strongly corroborated that the translational system would have thrived under early Earth conditions.


Bray, co-first author Timothy Lenz and co-principal investigators Glass and Williams published their results in the journal Proceedings of the National Academy of Sciences. The research was funded by the NASA Exobiology program. Glass is an assistant professor in Georgia Tech’s School of Earth and Atmospheric Sciences.


‘Textbook-rewriting results’


Amazingly, the atomic swaps barely changed the shape of the ribosome.


“It’s totally unbelievable this would work because biology makes very specific use of things. Change one atom and it can wreck a whole protein,” Williams said. “When we probed the structure, we saw that all three metals do essentially the same thing to the structure.”


When they tested the performance of the translational system with iron replacing magnesium, it was 50 to 80 percent as efficient as normal (with magnesium). “Manganese worked even better than iron,” Bray said.


“I think these may be textbook-rewriting results since the whole field of ribosome research involves magnesium,” Bray said. “Now, with what we’ve done, it’s no longer the case that only magnesium works.”


Primordial gas tent


Bray incubated ribosomes in the presence of magnesium, iron, or manganese inside a special chamber with an artificial atmosphere devoid of oxygen, like the Earth four billion years ago.


He found that the magnesium replacement went far beyond atoms in the ribosome.


“Surrounding the ribosome is also a huge cloud of magnesium atoms. It’s called an atmosphere, or shell, and engulfs it completely. I replaced everything, including that, and the whole system still worked.”


Eons down the road, the evolution of the translational system in the presence of magnesium may have given it an adaptive advantage. As oxygen levels on Earth rose, binding up free manganese and iron, and making them less available to biology, magnesium probably comfortably assumed the thousands of roles it occupies in the translational system today.


Author: Ben Brumfield | Source: Georgia Institute of Technology [November 10, 2018]



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Layout of Roman fort in Romania’s Pojejena determined

We now know the layout of a large Roman fort in Pojejena in western Romania, on the Serbiam border. It was a few hectares of land surrounded by an embankment, a wall and a ditch. Polish scientists determined that using geophysical methods.











Layout of Roman fort in Romania's Pojejena determined
Site of the Roman fort [Credit: M. Pisz]

The fort in Pojejena on today`s Romanian-Serbian border was probably built at the end of the first century AD. Its history is not completely clear to historians.


“We know that it was certainly an important strategic point. It is almost at the entrance to the Iron Gate, a rather long section of the middle Danube, which was not navigable in antiquity due to the rocky bottom”, says archaeologist Emil Jęczmienowski from the Institute of Archaeology of the University of Warsaw.


He is the leader of the project aimed at surveying the fort in Pojejena. The team also includes other researchers from the University of Warsaw and scientists from the National Museum of Banat in Timişoara and the Mountain Banat Museum in Resita (Romania). The research was financed by the National Science Centre.


Due to the location near the border, historians are not sure which Roman province governor the garrison in Pojejena was under – Dacia or Moesia. But it is known that it was a fort, not a legion camp, meaning that it was a smaller military facility, in which an auxiliary unit was stationed, possibly with a legion unit. In the case of Pojejena, these were probably units in the strength of two cohorts, a total of no more than a thousand soldiers, Jęczmienowski believes.











Layout of Roman fort in Romania's Pojejena determined
Geomagnetic scan [Credit: M. Pisz]

Until now, only a few spots in the fort have been studied by archaeologists. Scientists conducted excavations in various places, but they did not have a full picture of the fort – its size, shape and layout. The situation changed when the Polish team used geophysical research equipment.


“In the image we have obtained, the contours of the fort are clearly visible, which allows for a fairly accurate estimation of its dimensions – about 3 hectares, which is quite a lot for an auxiliary troops fort”, Jęczmienowski says.


He emphasises that the picture is so clear that it is possible to distinguish particular elements of the fortifications: the embankment and its reinforcement, the wall and ditch. But that`s not all. Scientists have also identified a number of structures within the fort, including the command building and probably the barracks.


“When we were choosing the set of methods for our research we expected good results, but what we managed to register exceeded our expectations. The responsiveness of the magnetic method in these specific conditions turned out to be very good, and despite the degradation caused mainly by the agrotechnical activity and erosion, the northern part of the fort is probably still fairly well preserved”, says Michał Pisz, PhD student at the Faculty of Geology of the University of Warsaw, responsible for the use of geophysical methods.











Layout of Roman fort in Romania's Pojejena determined
Setting up the equipment [Credit: M. Pisz]

“Determining cardinal orientation is one of the most important research elements that will allow us to better understand the history of this area during the Roman conquest, as well as many issues related to defence strategy, topography or the role of this extremely important garrison”, emphasises Dr. Agnieszka Tomas from the Institute of Archaeology, University of Warsaw.
As a result of the research project, archaeologists also determined the course of the main roads from the fort – and possibly also of the network of aqueducts that supported this military structure. The research also helped locate the civilian settlement that adjoined the fort.


Researchers are happy to have been able to explore the fort in Pojejena. It is one of the last such sites available for research in this area; many archaeological sites located downstream on both sides of the Danube were flooded as a result of the construction of a dam in the 1960s and 1970s.


Author: Szymon Zdziebłowski | Source: PAP – Science in Poland [November 10, 2018]



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Cultic building from the 6th millennium BC discovered in Kuwait

New discoveries at the Bahra 1 site show that this settlement from the 6th millennium BC was more developed than any other site from this period known from the Gulf region.











Cultic building from the 6th millennium BC discovered in Kuwait
Building complex with the cultic structure [Credit: S. Lenarczyk]

This year, the Kuwaiti-Polish Archaeological Mission headed by Prof. Piotr Bieliński from the Polish Centre of Mediterranean Archaeology, University of Warsaw in co-operation with Dr Sultan al-Duweish, the Director of the Department of Museums and Archaeology, and Dr Hamid al-Mutairi, Head of Excavations and Surveying Sector, discovered at this site a structure that may be interpreted as a cultic building. The Kuwaiti-Polish Archaeological Mission informed of their discoveries during a press conference organized by the Polish Embassy in Kuwait.
The prehistoric settlement of Bahra 1 is the largest of uncovered sites associated with the Ubaid culture, known so far from the Arabian Peninsula. The Ubaid culture, which first developed in Mesopotamia had a truly global sphere of interaction – objects characteristic for this culture, such as painted pottery, have been found at a large territory stretching from Palestine to the coast of the UAE. This led to the creation of first cities in the following period. But the most important development of the Ubaid culture – a new, more complex type of social structure – is less visible in the archaeological record.


Excavations at Bahra 1 uncovered at least 10 structures in an area stretching for c. 180 m. They yielded over 16 thousand fragments of pottery fragments, most of which came from Mesopotamian Ubaid-type vessels. Now archaeologists have encountered another trace of the culture’s influence – this time in the form of a building that has a different ground plan than any other structure excavated so far at Bahra 1.











Cultic building from the 6th millennium BC discovered in Kuwait
An Ubaid period vessel from Bahra 1 [Credit: A. Reiche]

“There are indications that this may be a building that had a cultic function – says Prof. Bieliński. – It combines elements characteristic for the local tradition with those of the Ubaid culture”, he explains.


If further research confirms these observations, this will be the oldest building of such function not just in Kuwait but in the whole Gulf region.


The current season was very fortunate for the Kuwaiti-Polish team, as it brought yet another discovery. In the vicinity of the „temple” excavations revealed a large fragment of an empty space surrounded by buildings.


“The size and regularity of this space bring to mind a plaza or village square. And this in turn indicates some sort of planning in the settlement’s spatial organization, which is very surprising at a site of such an early date”, Bieliński points out, adding that this is unheard of even at Ubaid-period sites in Mesopotamia.


The data from this year’s fieldwork at Bahra 1 will need to be studied before they can be scientifically published, but even now they confirm an impression voiced by many scientists researching the birth of civilization, that the roots of urban life, a model of life as we know it today, should be sought in the Ubaid period. The site of Bahra 1 shows that the inhabitants of the Kuwaiti desert were part of a large cultural and economic zone of influence that stretched from the Arabian Gulf shores to the Mediterranean coast.


Author: Agnieszka Szulc-Kajak | Source: University of Warsaw [November 10, 2018]



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Remains of 2,700-year-old city discovered in Iran

Iranian and German archaeologists have discovered the remains of a city belonging to the Achaemenid and Medieval times during their excavations in North Khorasan Province, northeast of Iran.


Remains of 2,700-year-old city discovered in Iran

Remains of 2,700-year-old city discovered in Iran

Remains of 2,700-year-old city discovered in Iran


Remains of 2,700-year-old city discovered in Iran

Remains of 2,700-year-old city discovered in Iran

Remains of 2,700-year-old city discovered in Iran










Remains of 2,700-year-old city discovered in Iran
Credit: IRNA

The city was discovered near Rivi hill, located 3 kilometres west of Ashkhaneh in North Khorasan.


Remains of 2,700-year-old city discovered in Iran

Remains of 2,700-year-old city discovered in Iran

Remains of 2,700-year-old city discovered in Iran


Remains of 2,700-year-old city discovered in Iran

Remains of 2,700-year-old city discovered in Iran

Remains of 2,700-year-old city discovered in Iran










Remains of 2,700-year-old city discovered in Iran
Credit: IRNA

This site was registered in 1967 as a national heritage site, and the first phase of archaeological explorations began in 2012.


Remains of 2,700-year-old city discovered in Iran

Remains of 2,700-year-old city discovered in Iran

Remains of 2,700-year-old city discovered in Iran


Remains of 2,700-year-old city discovered in Iran

Remains of 2,700-year-old city discovered in Iran

Remains of 2,700-year-old city discovered in Iran










Remains of 2,700-year-old city discovered in Iran
Credit: IRNA

A cemetery and structures from the Bronze Age to more contemporary eras as well as the remains of a city of the Median and Achaemenid period have also been found at this site.


Source: Iran Front Page [November 10, 2018]




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