среда, 12 декабря 2018 г.

Bryn Y Mor Prehistoric Stone Head, Oriel Ynys Mon, Llangefni, Anglesey, North Wales.

Bryn Y Mor Prehistoric Stone Head, Oriel Ynys Mon, Llangefni, Anglesey, North Wales.

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Did supernovae kill off large ocean animals at dawn of Pleistocene?

About 2.6 million years ago, an oddly bright light arrived in the prehistoric sky and lingered there for weeks or months. It was a supernova some 150 light years away from Earth. Within a few hundred years, long after the strange light in the sky had dwindled, a tsunami of cosmic energy from that same shattering star explosion could have reached our planet and pummeled the atmosphere, touching off climate change and triggering mass extinctions of large ocean animals, including a shark species that was the size of a school bus.

Did supernovae kill off large ocean animals at dawn of Pleistocene?
A nearby supernova remnant [Credit: NASA]

The effects of such a supernova — and possibly more than one — on large ocean life are detailed in a paper just published in Astrobiology.

“I’ve been doing research like this for about 15 years, and always in the past it’s been based on what we know generally about the universe — that these supernovae should have affected Earth at some time or another,” said lead author Adrian Melott, professor emeritus of physics & astronomy at the University of Kansas. “This time, it’s different. We have evidence of nearby events at a specific time. We know about how far away they were, so we can actually compute how that would have affected the Earth and compare it to what we know about what happened at that time — it’s much more specific.”

Melott said recent papers revealing ancient seabed deposits of iron-60 isotopes provided the “slam-dunk” evidence of the timing and distance of supernovae.

“As far back as the mid-1990s, people said, ‘Hey, look for iron-60. It’s a telltale because there’s no other way for it to get to Earth but from a supernova.’ Because iron-60 is radioactive, if it was formed with the Earth it would be long gone by now. So, it had to have been rained down on us. There’s some debate about whether there was only one supernova really nearby or a whole chain of them. I kind of favor a combo of the two — a big chain with one that was unusually powerful and close. If you look at iron-60 residue, there’s a huge spike 2.6 million years ago, but there’s excess scattered clear back 10 million years.”

Melott’s co-authors were Franciole Marinho of Universidade Federal de Sao Carlos in Brazil and Laura Paulucci of Universidade Federal do ABC, also in Brazil.

According to the team, other evidence for a series of supernovae is found in the very architecture of the local universe.

“We have the Local Bubble in the interstellar medium,” Melott said. “We’re right on its edge. It’s a giant region about 300 light years long. It’s basically very hot, very low-density gas — nearly all the gas clouds have been swept out of it. The best way to manufacture a bubble like that is a whole bunch of supernovae blows it bigger and bigger, and that seems to fit well with idea of a chain. When we do calculations, they’re based on the idea that one supernova that goes off, and its energy sweeps by Earth, and it’s over. But with the Local Bubble, the cosmic rays kind of bounce off the sides, and the cosmic-ray bath would last 10,000 to 100,000 years. This way, you could imagine a whole series of these things feeding more and more cosmic rays into the Local Bubble and giving us cosmic rays for millions of years.”

Did supernovae kill off large ocean animals at dawn of Pleistocene?
Muons showering Earth may have spelled curtains for Megalodon, a school-bus-sized shark,
2.6 million years ago [Credit: Karen Carr]

Whether or not there was one supernova or a series of them, the supernova energy that spread layers of iron-60 all over the world also caused penetrating particles called muons to shower Earth, causing cancers and mutations — especially to larger animals.

“The best description of a muon would be a very heavy electron – but a muon is a couple hundred times more massive than an electron,” Melott said. “They’re very penetrating. Even normally, there are lots of them passing through us. Nearly all of them pass through harmlessly, yet about one-fifth of our radiation dose comes by muons. But when this wave of cosmic rays hits, multiply those muons by a few hundred. Only a small faction of them will interact in any way, but when the number is so large and their energy so high, you get increased mutations and cancer — these would be the main biological effects. We estimated the cancer rate would go up about 50 percent for something the size of a human — and the bigger you are, the worse it is. For an elephant or a whale, the radiation dose goes way up.”

A supernova 2.6 million years ago may be related to a marine megafaunal extinction at the Pliocene-Pleistocene boundary where 36 percent of the genera were estimated to become extinct. The extinction was concentrated in coastal waters, where larger organisms would catch a greater radiation dose from the muons.

According to the authors of the new paper, damage from muons would extend down hundreds of yards into ocean waters, becoming less severe at greater depths: “High energy muons can reach deeper in the oceans being the more relevant agent of biological damage as depth increases,” they write.

Indeed, a famously large and fierce marine animal inhabiting shallower waters may have been doomed by the supernova radiation.

“One of the extinctions that happened 2.6 million years ago was Megalodon,” Melott said. “Imagine the Great White Shark in ‘Jaws,’ which was enormous — and that’s Megalodon, but it was about the size of a school bus. They just disappeared about that time. So, we can speculate it might have something to do with the muons. Basically, the bigger the creature is the bigger the increase in radiation would have been.”

The KU researcher said the evidence of a supernova, or series of them, is “another puzzle piece” to clarify the possible reasons for the Pliocene-Pleistocene boundary extinction.

“There really hasn’t been any good explanation for the marine megafaunal extinction,” Melott said. “This could be one. It’s this paradigm change — we know something happened and when it happened, so for the first time we can really dig in and look for things in a definite way. We now can get really definite about what the effects of radiation would be in a way that wasn’t possible before.”

Source: University of Kansas [December 11, 2018]



Small and isolated habitat patches crucial to species survival

Small, local patches of habitat could be playing a much bigger role in conserving biodiversity than you think, according to new research.

Small and isolated habitat patches crucial to species survival
Eastern rosella at Edithvale wetland [Credit Wayne Butterworth]

The global study just published in the Proceedings of the National Academy of Sciences looked at the conservation values of vegetation patches in 27 countries on four continents, and considered their size and distance to other habitat.

The results were surprising according to lead researcher Professor Brendan Wintle from Melbourne University.

“Compared to large and well connected habitat areas, small and isolated patches of habitat have generally been treated as not very important to conservation,” said Professor Wintle. “What we have found, however, is that small and isolated habitat areas are very important to the survival of many rare and endangered species.”

“The environment is suffering a death by a thousand cuts,” Wintle continued. “We need to re-think vegetation management regulations and policies that allow small patches of vegetation to be destroyed.”

Co-author Dr. Sam Veloz, Climate Adaptation Group Director at Point Blue Conservation Science, added “We have many existing processes in place to fund restoration or conservation activities that are largely focused on large patches of habitat. While it’s important to continue these efforts, our paper emphasizes that small but important habitat patches should be included in an overall conservation portfolio.”

An example from the paper explored suitable habitat for four songbird species in California and Oregon (the streaked horned lark, savannah sparrow, Western meadowlark and the Oregon vesper sparrow). Research showed that highly fragmented parts of the study areas for each species contain habitat patches of very high conservation value. And the four species studied have ranges primarily in those small, isolated patches.

Dr. Heini Kujala from the University of Melbourne, another co-author, said that once you start considering how much habitat is left for a species, small patches can be very valuable.

“Small habitat patches can sometimes be the last pieces of a once widespread habitat. For species that rely on this type of habitat that makes them very important,” said Dr. Kujala.

“Definitely we are not saying that it is an improvement to cut up big habitat areas into smaller pieces, rather that many of the small pieces that we have left are really important for conservation.”

The study’s authors hope that the research will raise awareness among planners, land managers, scientists, and the community about the value of small vegetation patches.

Source: University of Melbourne [December 11, 2018]



Degrading permafrost puts Arctic infrastructure at risk by mid-century

Seventy percent of the current infrastructure in the Arctic has a high potential to be affected by thawing permafrost in the next 30 years. Even meeting the climate change targets of the Paris Agreement will not substantially reduce those projected impacts, according to a new study published in Nature Communications.

Degrading permafrost puts Arctic infrastructure at risk by mid-century
UAF researcher Vladimir Romanovsky poses near Fairbanks, Alaska in a place where permafrost has thawed,
causing a surface disruption [Credit: University of Alaska Fairbanks]

“Much more needs to be done to prepare Alaska and Alaskans for the adverse consequences of coming changes in permafrost and climate,” said Vladimir Romanovsky, a scientist with the University of Alaska Fairbanks Geophysical Institute who has been monitoring permafrost across Alaska for 25 years.

Permafrost is ground that is frozen year-round for a minimum of two years. When it thaws, it can change from solid earth into mud. In many cases, the ground will slump, leading to destructive failure in any structures erected there.

“These observations have led me to believe that the global warming is not a ‘fake’ but the reality,” Romanovsky said. “And here, in Alaska, we are dealing already and will be dealing even more in the near future with this reality.”

Romanovsky is one of the study’s authors, along with researchers from Finland, Norway, Russia and Michigan. The research is the first to explicitly show the amount of fundamental infrastructure across the Northern Hemisphere that is at risk of structural failure from permafrost thaw caused by climate change.

The paper reports that by 2050, about three-quarters of the population now living on permafrost, about 3.6 million people, will be affected by damage to infrastructure from permafrost thaw. In Alaska, about 340 miles of the trans-Alaska oil pipeline traverses ground where near-surface permafrost may thaw by 2050.

“The results show that most fundamental Arctic infrastructure will be at risk, even if the Paris Agreement target is achieved,” the authors write. However, after 2050, attaining the Paris Agreement goals would make a clear difference in potential damage to infrastructure.

The authors looked at measurements of ground temperature, annual thaw depth and other data to make their projections. They note that because of the uncertainties, the amount of infrastructure at risk from permafrost thaw is probably not much smaller than their estimate, but could be substantially larger.

Damage to industrial facilities such as pipelines could lead to major ecosystem disruption if it results in spills. Energy supplies, national security and general economic activity could be adversely affected as well, the authors write. The Yamal-Nenets region in northwestern Siberia is the source of more than one-third of the European Union’s pipeline imports of natural gas, for example.

Many parts of the Arctic’s infrastructure have relatively short lifespans. Planners and engineers need to know in detail where permafrost is most likely to thaw as they plan for replacements, upgrades and maintenance. This study mapped such areas at a resolution of 0.6 miles, allowing them to target mitigation where it is most needed.

Source: University of Alaska Fairbanks [December 11, 2018]



Arctic Report Card tracks region’s environmental changes

NOAA’s annual report card on the Arctic, released today at the American Geophysical Union fall meeting in Washington, D.C., measures the changing climate of the polar region including warmer air and ocean temperatures and declines in sea-ice that are driving shifts in animal habitats.

Arctic Report Card tracks region’s environmental changes
Eyeing the Arctic: The southern Greenland town of Narsaq. Photo taken during a NASA
Operation IceBridge flight April 26, 2018 [Credit: NASA/Joe MacGregor]

Now in its 13th year, the 2018 Arctic Report Card is a peer-reviewed report that provides an annual status update on the region and compares these observations to the long-term record. It was compiled from the research of 81 scientists working for governments and academia in 12 nations. This information can be used to inform decisions by local, state and federal leaders as Arctic residents confront the challenges and opportunities posed by a rapidly changing climate and ecosystem.
“The environmental changes in the Arctic underscore why NOAA continues to invest in Arctic research and activities, which improve the nation’s economic competitiveness, national security, and the sustainable management of natural resources,” said retired Navy Rear Adm. Timothy Gallaudet, Ph.D., acting under secretary of commerce for oceans and atmosphere at NOAA, who led the news conference to release the report card. “This report will also help guide NOAA’s priorities in better understanding the role of the Arctic in climate change and extreme weather; sustaining and growing fisheries; and supporting adaptation and economic opportunities in the region.”

This year’s report shows that the Arctic region experienced the second-warmest air temperatures ever recorded; the second-lowest overall sea-ice coverage; lowest recorded winter ice in the Bering Sea; and earlier plankton blooms due to early melting of sea ice in the Bering Sea.
In addition to annual updates on ocean temperature, snow cover, tundra greenness and melting on the Greenland Ice Sheet, the report card also includes reports on multi-year environmental changes, including a long-term population decline of the region’s iconic wildlife species, the caribou. Other multi-year essays focused on the expansion northward of toxic harmful algae and significant concentrations of microplastic pollution that are transported by ocean currents into the Arctic Ocean from other parts of the global ocean.

Arctic Report Card tracks region’s environmental changes
Declining Arctic sea ice: The 2018 Arctic Report Card found the Arctic region had the second-lowest overall sea-ice
coverage on record. The map shows the age of sea ice in the Arctic ice pack in March 1985 (left) and March 2018 (right)
. Ice that is less than a year old is darkest blue. Ice that has survived at least 4 full years is white [Credit: Maps were
provided by NOAA Climate.gov and based on data provided by Mark Tschudi./University of Colorado/
CCAR (NOAA Climate.gov)]

This report card is just one of many aspects of NOAA’s role in the Arctic region. NOAA, alongside many partners, is monitoring Arctic conditions, pioneering innovative technologies, and creatively collecting data and other scientific information.
For example, new technology is revolutionizing our understanding of the Arctic’s changing environment, beginning to fill critical gaps in ocean and atmospheric observations. This technology is unmanned, fast, cost-effective, sturdy enough to withstand icy temperatures, and able to collect quality data for lengthy periods. Further, NOAA Polar-orbiting satellites fly over the Arctic 28 times daily, collecting data vital to improve weather forecasts, help fisheries increase catch, and support safe, efficient navigation in challenging waters. Additionally, as Arctic waters become increasingly ice-free, and commerce and other interests grow, NOAA is working to update nautical charts and calculate tide and current predictions.

Source: National Oceanic and Atmospheric Administration (NOAA) [December 11, 2018]



A glimpse into future oceans

Something peculiar is happening in the azure waters off the rocky cliffs of Ischia, Italy. There, streams of gas-filled volcanic bubbles rising up to the surface are radically changing life around them by making seawater acidic. Stanford researchers studying species living near these gassy vents have learned what it takes to survive in acidic waters, providing a glimpse of what future oceans might look like as they grow more acidic.

A glimpse into future oceans
Volcanic carbon dioxide seeps from the ocean floor near Ischia, Italy [Credit: Pasquale Vassallo,
Stazione Zoologica Anton Dohrn]

Their findings, published in Nature Communications, suggest that ocean acidification driven by human-caused carbon dioxide emissions could have a larger impact than previously thought.

“When an organism’s environment becomes more acidic, it can dramatically impact not only that species, but the overall ecosystem’s resilience, function and stability,” said Stanford marine biologist Fiorenza Micheli, lead author on the paper. “These transformations ultimately impact people, especially our food chains.”

A natural laboratory

Most ocean acidification studies to date have taken place in laboratories, making it impossible to assess how whole ecosystems comprised of multiple, interacting species would be affected. The real-life laboratory provided researchers an opportunity to examine dozens of species, from sea urchins to marine snails, that live in areas of different acidity along Ischia’s volcanic carbon dioxide vents. In addition to studying how species diversity changed with acidification, they analyzed species traits, such as diet and growth, that influence how well the ecosystem performs. For example, sea snails were smaller in more acidic water, as their shells take longer to grow and are thinner and more brittle. These harmful effects on sea snails, a key food for animals higher up in the food chain, may affect fish populations.

Stanford researchers studying species living near underwater volcanic vents have learned what it takes 

to survive in acidic waters [Credit: Pietro Sorvino and Pasquale Vassallo]

Overall, the researchers found that the active venting zones with the most acidic waters were home to not only the least number of species, but also the lowest amounts of “functional diversity” – the range of ecosystem-support services or roles that each species can provide.
“Studying the natural carbon dioxide vents in Ischia allowed us to unravel which traits from different species, like snail shell strength, were more vulnerable to ocean acidification. These results illuminate how oceans will function under different acidification scenarios in the future,” said lead author Nuria Teixidó, a marine biologist from Stazione Zoologica Anton Dohrn in Italy, who was a visiting researcher at Stanford during the research.

Acidification in the waters of Ischia displaced long-lived species, such as corals, that form habitat for other species – a process already often witnessed on reefs across the world. The researchers also found that high levels of carbon dioxide and more acidity favored species with short life spans and fast turnover as they are the only species that can resist these environmental conditions. This change could lead to further diversity loss and instability in the oceans, as biodiversity tends to increase an ecosystem’s stability.

A glimpse into future oceans
Biodiversity loss is mapped along a natural CO2 gradient [Credit: Nuria Teixidó,
Stazione Zoologica Anton Dohrn]

A broader application

Localized case studies such as Ischia can shed light on how future global environmental conditions may affect ocean life. Beyond losing biodiversity, ocean acidification will threaten food security for millions of people who depend on seafood, along with tourism and other ocean-related economies.

“The effects of ocean acidification on whole ecosystems and their functioning are still poorly understood,” said Micheli, a professor of biology. “In Ischia, we have gained new insights into what future oceans will look like and what key services, like food production and coastal production, will be lost when there is more carbon dioxide in the water.”

Author: Nicole Kravec | Source: Stanford University [December 11, 2018]



Transformed: the plant whose sex life fascinated Charles Darwin

Researchers have genetically transformed the Common Primrose (Primula vulgaris) for the first time in a development that could shed light on one of the plant world’s most renowned reproductive systems.

Transformed: the plant whose sex life fascinated Charles Darwin
Credit: John Innes Historical Collection

The complicated sex life of Primula was a subject that fascinated Charles Darwin and generations of geneticists that followed because it’s one of the best examples of heteromorphic flower development.

Heteromorphy (or heterostyly) is a phenomenon in which plants exhibit two or three distinct forms of flowers based on the position of the male and female sex organs. Now, some of the secrets that eluded Darwin could be revealed following the biotechnological success announced by researchers from the John Innes Centre, the University of East Anglia (UEA) and the Earlham Institute.

The technology known as Agrobacterium-mediated plant transformation involves using soil bacteria to insert or modify genes in a plant genome. Genetic transformation is a valuable tool that allows researchers to study gene function and genetically controlled characteristics in organisms.

It is a research method routinely used on model organisms such as Nicotiana benthamiana and Arabidopsis thaliana to understand the molecular workings of plants. However, these species cannot be used to study heteromorphy because their flowers are all homomorphic which means they are able to self-fertilise.

“Now we have a transformation system we can use gene editing tools such as CRISPR-Cas9 to work out exactly what the gene function is that controls heteromorphy in the Primula family,” says Sadiye Hayta, of the John Innes Centre.

“Longer term, there may be implications for commercial crops. If we understand the roles of these different genes we could take them over to a commercial crop and use it in a hybrid system,” she adds.

Until now attempts to transform Primula have been unsuccessful because the plant has proved resistant to laboratory regeneration of whole plants from tissue culture.

The new transformation protocols reported in the peer-reviewed journal Plant Methods will allow the scientists of today to study the Primula at a molecular level.

The flowering plant is one of the best-known examples of heteromorphic flower development. This reproductive system enthralled not only Darwin but many leading geneticists from the early 1900s including William Bateson, the first director of the John Innes Centre and colleagues JBS Haldane, Cyril Darlington and Dorothea de Winton.

Darwin, in a landmark paper of 1862, worked out the functional significance of the different anatomical formations: they made the plants self-incompatible. This is Nature’s way of promoting cross-pollination to maintain genetic variation in the population, driving natural selection.

Fundamental research into heteromorphy has continued. In a research paper in 2016 a John Innes Centre – University of East Anglia team led by Professor Philip Gilmartin identified the S-Locus supergene that controls heteromorphy as described by Darwin.

Armed with this fundamental knowledge and a the newly announced transformation system, scientists can delve deeper into the mysteries of heteromorphy.

Co-author Mark Smedley, of the John Innes Centre says: “It is not every day you get to work on a paper that references Darwin. This is a fundamental story that scientists have been trying to unravel for 200 years.”

Professor Philip Gilmartin of the UEA whose laboratory started out on this scientific mission more than 20 years ago, said: “The development of a Primula transformation system is an important component of our lab’s long-term study to identify and characterise the genes that control development of the two forms of Primula flower studied by Charles Darwin.”

It’s a piece of research that would have excited Darwin. Towards the end of his illustrious career the author of On the Origin of Species remarked:

“I do not think anything in my scientific life has given me so much satisfaction as making out the meaning of the structure of these plants.”

Source: John Innes Centre [December 11, 2018]



Nanya Rock Formations, Taiwan | #Geology #GeologyPage…

Nanya Rock Formations, Taiwan | #Geology #GeologyPage #Taiwan

The northernmost scenic spot of the Northeast Coast.

Nanya is renowned for the wind and sea sculpted rock formations scattered along its shores. The primary site for viewing rock formations is called Nanya Peculiar Rocks.

Geology Page



Pyromorphite with Plumbogummite | #Geology #GeologyPage #Mineral…

Pyromorphite with Plumbogummite | #Geology #GeologyPage #Mineral

Locality: Yangshuo Mine, Yangshuo, Guilin Prefecture, Guangxi Zhuang Autonomous Region China

Specimen size: 7 × 6.8 × 3.9 cm

Main crystal size: 2.3 × 1 cm

Photo Copyright © Fabre Minerals

Geology Page



Rhodochrosite after Serandite with Analcime and Aegirine |…

Rhodochrosite after Serandite with Analcime and Aegirine | #Geology #GeologyPage #Mineral

Locality: Poudrette Quarry, Mont Saint-Hilaire, La Vallée-du-Richelieu RCM, Montérégie, Québec Canada

Specimen size: 5.8 × 3.5 × 1.7 cm

Main crystal size: 5.2 × 0.6 cm

Photo Copyright © Fabre Minerals

Geology Page



2018 December 12 M43: Orion Falls Image Credit & Copyright:…

2018 December 12

M43: Orion Falls
Image Credit & Copyright: Zhuoqun Wu, Chilescope Telescope 2

Explanation: Is there a waterfall in Orion? No, but some of the dust in M43 appears similar to a waterfall on Earth. M43, part of the Orion Molecular Cloud Complex, is the often imaged but rarely mentioned neighbor of the more famous M42. M42, which includes many bright stars from the Trapezium cluster, lies above the featured scene. M43 is itself a star forming region and although laced with filaments of dark dust, is composed mostly of glowing hydrogen. The entire Orion field, located about 1600 light years away, is inundated with many intricate and picturesque filaments of dust. Opaque to visible light, dark dust is created in the outer atmosphere of massive cool stars and expelled by a strong outer wind of protons and electrons.

∞ Source: apod.nasa.gov/apod/ap181212.html

HiPOD (11 December 2018): Swiss Cheese on a Red PlanetThe…

HiPOD (11 December 2018): Swiss Cheese on a Red Planet

The Martian south polar cap is a layer of carbon dioxide ice, full of pits that make it look like Swiss cheese. The pits form when the Sun heats the ice and makes it sublimate (transform from a solid to a gas). Because it’s at the pole, the Sun never gets very high in the sky, so steep slopes get more heat and sublimate faster, causing pits to form and grow. This is balanced by new carbon dioxide frost that forms on flatter areas.

NASA/JPL/University of Arizona

Iron Age chariot burial found in East Yorkshire

Archaeologists have made an “unparalleled” discovery in East Yorkshire of a chariot buried with two horses, which look as if they “were leaping upwards out of the grave.”

Iron Age chariot burial found in East Yorkshire
The chariot with its ponies [Credit: David Keys]

The pair had been carefully positioned in the Iron Age grave at Pocklington with their back legs bent and hooves just off the ground – ready to spring into the next life.

The chariot – with a man aged in his late 40 upwards in a fetal position inside – had also been buried upright, as though the vehicle was ready to roll on “into any future life.”

Archaeologists say the horses may have originally been buried with their heads sticking out of the grave, although when found they were headless.

The discovery comes just a year after another Iron Age chariot and two well-preserved horses were discovered on another building site in the town, David Wilson Homes’ Pavilion Square development.

The horses were buried with a “highly regarded member of the community” who was in his late 40s or older, whose head was surrounded by the bones of six piglets, believed to be an offering, along with a well-preserved shield and a highly decorative brooch.

East Yorkshire is known for its chariot burials but Paula Ware from MAP Archaeological Practice said the type of burial rite had “no British parallel.”

Iron Age chariot burial found in East Yorkshire
The excavation of an Iron Age chariot burial near Pocklington, Yorkshire
[Credit: David Keys]

She said: “We couldn’t tell how they were placed in the grave. Both were still upright and they were placed as though in motion as if they were leaping out of the grave. It looked as though their skulls were removed centuries ago.

“Possibly the heads were coming out of the graves. Did they go in alive who knows? There’s no evidence of a ramp. This is a new burial rite which has never been seen before.

“How spectacular this is – and what time and effort must have gone into it and the people who must have taken part in this burial process, digging this 4.7m by 3.9m grave.

“There is more pig bone in this burial than there has been seen in burials across the Wolds.

“He is honoured with at least six piglets – normally there would be a quarter of a jaw. He was someone so significant.”

Nearby was another amazing find – a young man aged 17 to 25 – who had been “ritually speared” with 10 iron and bone spears.

Iron Age chariot burial found in East Yorkshire
The excavation of the remains of a speared Iron Age man near Pocklington, Yorkshire
[Credit: David Keys]

He had suffered blunt force trauma indicative of being in a conflict. It has been suggested by other experts following similar discoveries that it could be a ritual to ensure the corpse remained dead.

But Ms Ware believes it was to release the youngster’s spirit, and was a sign of respect from the community.

Ms Ware said: “We will never know because there was no written word and we can only speculate.” Simon Usher, managing director at Persimmon Homes Yorkshire, said: “Everyone has been absolutely thrilled by the finds.

“Keeping the news under wraps while the excavation was completed has been a real challenge, but so important to ensure the integrity of the site.”

Author: Alex Wood | Source: The Yorkshire Post [December 09, 2018]



Solar activity research provides insight into sun’s past, future

Andrés Muñoz-Jaramillo of Southwest Research Institute and José Manuel Vaquero of the University of Extremadura have developed a new technique for looking at historic solar data to distinguish trustworthy observations from those that should be used with care. This work is critical to understanding the Sun’s past and future as well as whether solar activity plays a role in climate change.

Solar activity research provides insight into sun's past, future
A team led by SwRI integrated a sunspot drawing made by Hevelius in 1644 (top) with images from NASA’s Solar
Dynamics Observatory to illustrate how widely varying telescopes and observation techniques can affect data.
The team integrated data from 700 observations to assess the reliability of historical data,
to better understand the history of solar activity [Credit: NASA/SDO/SwRI]

“Scientists have been monitoring solar activity since Galileo made the first drawings in 1612 by counting sunspots and groups of sunspots,” said SwRI’s Dr. Andrés Muñoz-Jaramillo, a senior research scientist who is first author of a paper in Nature Astronomy outlining the research. “However, putting all observations in perspective is quite challenging due to wide-ranging observation techniques and telescope magnifications used. We see much more now and our understanding of what we see changes the way we count spots.”
The team created a technique that takes all historic data gathered and digitized thus far and combines them visually, to provide a complete picture of the data we have and where are we missing information. Roughly every 11 years, the magnetic structure and activity of the Sun cycle between periods known as solar minimum and solar maximum. During solar maximum, the Sun emits high levels of solar radiation, ejects large amounts solar material and displays large numbers of intense sunspots, flares and other phenomena. During solar minimum, this activity is muted. Changes on the Sun cause effects in space, in the atmosphere and on Earth’s surface.

The Sun also experiences century-long variations, including periods of abnormally low solar activity called grand minima. Maunder Minimum refers to a 70-year period between 1645 and 1715 when observations revealed thousands of days without sunspots. The term was the title of a 1976 paper that first identified these longer cycles, named for a husband-wife team of solar astronomers from the late 17th century. In contrast, modern observations typically record hundreds of days without sunspots over similar periods of time.

“Scientists are investigating whether Maunder Minimum could serve as archetype of a grand minimum in magnetic activity for the Sun and other stars,” Muñoz said. However, data prior to, during and after the Maunder Minimum, is less reliable and lacks the precision and coverage of today’s measurements. Recent reevaluations of sunspot observations have yielded a conflicted view on the evolution of solar activity over the last 400 years.

“Due to our lack coverage we don’t know if the Sun took decades to recover from the Maunder Minimum to the levels of solar activity we see today, or if it was quick as if a switch had been turned on,” Muñoz said. “There is currently a team of experts from all over the world working hard to find the best way of combining these data. In the meantime, one has to be very careful when using historic sunspot data to study potential links between the Sun and changes in terrestrial climate, given that these effects would be complex and subtle. Our work uses historical data to provide context to users of these estimates that may not be aware of their limitations.”

Source: Southwest Research Institute [December 10, 2018]



Astronomers find evidence for carbon-rich surface on Ceres

A team led by Southwest Research Institute has concluded that the surface of dwarf planet Ceres is rich in organic matter. Data from NASA’s Dawn spacecraft indicate that Ceres’s surface may contain several times the concentration of carbon than is present in the most carbon-rich, primitive meteorites found on Earth.

Astronomers find evidence for carbon-rich surface on Ceres
NASA’s Dawn spacecraft captured this 12.5-mile-across close-up of the central peak of the 99-mile-wide Urvara
impact crater on Ceres. The remarkable 6,500-foot central ridge is made from materials uplifted from depth,
 arising from terrains enriched with products of rock-water interactions, such as carbonates

“Ceres is like a chemical factory,” said SwRI’s Dr. Simone Marchi, a principal scientist who was the lead author of research published in Nature Astronomy. “Among inner solar system bodies, Ceres’ has a unique mineralogy, which appears to contain up to 20 percent carbon by mass in its near surface. Our analysis shows that carbon-rich compounds are intimately mixed with products of rock-water interactions, such as clays.”
Ceres is believed to have originated about 4.6 billion years ago at the dawn of our solar system. Dawn data previously revealed the presence of water and other volatiles, such as ammonium derived from ammonia, and now a high concentration of carbon. This chemistry suggests Ceres formed in a cold environment, perhaps outside the orbit of Jupiter. An ensuing shakeup in the orbits of the large planets would have pushed Ceres to its current location in the main asteroid belt, between the orbits of Mars and Jupiter.

“With these findings, Ceres has gained a pivotal role in assessing the origin, evolution and distribution of organic species across the inner solar system,” Marchi said. “One has to wonder about how this world may have driven organic chemistry pathways, and how these processes may have affected the make-up of larger planets like the Earth.”

Astronomers find evidence for carbon-rich surface on Ceres
SwRI scientists constructed a possible schematic path for the evolution of Ceres’ upper crust. The figure shows
 the presence of carbonaceous chondrite-like materials (black) mixed with products of aqueous alteration
such as phyllosilicates, carbonates and magnetite (green) and organics (orange). Shaded blue regions indicate
water, and blue lines represent conduits for water migration. Organics may have formed in place during aqueous
alteration or could have been concentrated by fluids ascending to the upper crust, resulting in the inferred
higher-than-chondritic carbon concentration on Ceres’ surface. Over time, the surface gets homogenized
by mixing due to collisions and other processes [Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA]

Geophysical, compositional and collisional models based on Dawn data revealed that Ceres’ partially differentiated interior has been altered by fluid processes. Dawn’s Visible and Infrared Mapping Spectrometer has shown that the overall low albedo of Ceres” surface is a combination of rock-water interaction products such as phyllosilicates and carbonates and a significant amount of spectrally neutral darkening agents, such as an iron oxide called magnetite.
Because Dawn’s Gamma Ray and Neutron Detector limits magnetite to only a few percent by mass, the data point to the presence of an additional darkening agent, probably amorphous carbon, a carbon-rich organic material. Interestingly, specific organic compounds have also been detected near a 31-mile-wide impact crater named Ernutet, giving further support to the widespread presence of organics in Ceres’ shallow subsurface.

The new study also finds that 50-60 percent of Ceres’ upper crust may have a composition similar to primitive carbonaceous chondrite meteorites. This material is compatible with contamination from infalling carbonaceous asteroids, a possibility supported by Ceres’ battered surface.

“Our results imply that either Ceres’ accreted ultra-carbon-rich materials or that carbon was concentrated in its crust,” said said Marchi. “Both potential scenarios are important, because Ceres’ mineralogical composition indicates a global-scale event of rock-water alteration, which could provide conditions favorable to organic chemistry.”

Source: Southwest Research Institute [December 10, 2018]



OSIRIS-REx discovers water on asteroid, confirming Bennu as excellent mission target

From August through early December, the OSIRIS-REx spacecraft aimed three of its science instruments toward Bennu and began making the mission’s first observations of the asteroid. During this period, the spacecraft traveled the last 1.4 million miles (2.2 million km) of its outbound journey to arrive at a spot 12 miles (19 km) from Bennu on Dec. 3. The science obtained from these initial observations confirmed many of the mission team’s ground-based observations of Bennu and revealed several new surprises.

OSIRIS-REx discovers water on asteroid, confirming Bennu as excellent mission target
This mosaic image of asteroid Bennu is composed of 12 PolyCam images collected on Dec. 2 by the OSIRIS-REx
spacecraft from a range of 15 miles (24 km) [Credit: NASA/Goddard/University of Arizona]

Team members of the mission, which is led by the University of Arizona, presented the results at the Annual Fall Meeting of the American Geophysical Union, or AGU, in Washington, D.C. on Dec. 10.

In a key finding for the mission’s science investigation, data obtained from the spacecraft’s two spectrometers, the OSIRIS-REx Visible and Infrared Spectrometer (OVIRS) and the OSIRIS-REx Thermal Emissions Spectrometer (OTES), reveal the presence of molecules that contain oxygen and hydrogen atoms bonded together, known as “hydroxyls.” The team suspects that these hydroxyl groups exist globally across the asteroid in water-bearing clay minerals, meaning that at some point, the rocky material interacted with water. While Bennu itself is too small to have ever hosted liquid water, the finding does indicate that liquid water was present at some time on Bennu’s parent body, a much larger asteroid.

“This finding may provide an important link between what we think happened in space with asteroids like Bennu and what we see in the meteorites that scientists study in the lab,” said Ellen Howell, senior research scientist at the UA’s Lunar and Planetary Laboratory (LPL) and a member of the mission’s spectral analysis group. “It is very exciting to see these hydrated minerals distributed across Bennu’s surface, because it suggests they are an intrinsic part of Bennu’s composition, not just sprinkled on its surface by an impactor.”

“The presence of hydrated minerals across the asteroid confirms that Bennu, a remnant from early in the formation of the solar system, is an excellent specimen for the OSIRIS-REx mission to study the composition of primitive volatiles and organics,” said Amy Simon, OVIRS Deputy Instrument Scientist at NASA Goddard Space Flight Center.

Additionally, data obtained from the OSIRIS-REx Camera Suite (OCAMS) corroborate ground-based radar observations of Bennu and confirm that the original model — developed in 2013 by OSIRIS-REx Science Team Chief Michael Nolan, now based at LPL, and collaborators — closely predicted the asteroid’s actual shape. Bennu’s diameter, rotation rate, inclination and overall shape presented almost exactly as projected.

Soon after the asteroid later named Bennu was discovered in 1999, Nolan’s group used the Arecibo Observatory in Puerto Rico to gather clues about its size, shape and rotation by bouncing radar waves off of it during one of its close approaches to Earth, about five times the distance between Earth and the moon.

This preliminary shape model of asteroid Bennu was created from a compilation of images taken by OSIRIS-REx’s 

PolyCam camera during the spacecraft’s approach toward Bennu during the month of November. 

This 3D shape model shows features on Bennu as small as six meters 

[Credit: NASA/Goddard/University of Arizona]

“Radar observations don’t give us any information about colors or brightness of the object, so it is really interesting to see the asteroid up close through the eyes of OSIRIS-REx,” Nolan said. “As we are getting more details, we are figuring out where the craters and boulders are, and we were very pleasantly surprised that virtually every little bump we saw in our radar image back then is actually really there.”

The mission team used this ground-based Bennu model when designing the OSIRIS-REx mission. The accuracy of the model means that the mission, spacecraft, and planned observations were appropriately designed for the tasks ahead at Bennu.

One outlier from the predicted shape model is the size of the large boulder near Bennu’s south pole. The ground-based shape model calculated this boulder to be at least 33 feet (10 meters) in height. Preliminary calculations from OCAMS observations show that the boulder is closer to 164 feet (50 meters) in height, with a width of approximately 180 feet (55 meters).

As expected, the initial assessment of Bennu’s regolith indicates that the surface of Bennu is a mix of very rocky, boulder-filled regions and a few relatively smooth regions that lack boulders. However, the quantity of boulders on the surface is higher than was expected. The team will make further observations at closer ranges to more accurately assess where a sample can be taken on Bennu for later return to Earth.

“Our initial data show that the team picked the right asteroid as the target of the OSIRIS-REx mission. We have not discovered any insurmountable issues at Bennu so far,” said Dante Lauretta, OSIRIS-REx principal investigator and professor of planetary science and cosmochemistry at LPL. “The spacecraft is healthy and the science instruments are working better than required. It is time now for our adventure to begin.”

“What used to be science fiction is now a reality,” said UA President Robert C. Robbins. “Our work at Bennu brings us a step closer to the possibility of asteroids providing astronauts on future missions into the solar system with resources like fuel and water.”

The mission is currently performing a preliminary survey of the asteroid, flying the spacecraft in passes over Bennu’s north pole, equator and south pole at ranges as close as 4.4 miles (7 km) to better determine the asteroid’s mass. This survey also provides the first opportunity for the OSIRIS-REx Laser Altimeter (OLA), an instrument contributed by the Canadian Space Agency, to make observations now that the spacecraft is in proximity to Bennu. The spacecraft’s first orbital insertion is scheduled for Dec. 31, and OSIRIS-REx will remain in orbit until mid-February 2019, when the mission transitions into the next survey phase. During this first orbital phase, the spacecraft will orbit the asteroid at a range of 0.9 miles (1.4 km) to 1.24 miles (2 km) from the center of Bennu — setting two new records for the smallest body ever orbited by a spacecraft and the closest orbit of a planetary body by any spacecraft.

Author: Erin Morton and Daniel Stolte | Source: University of Arizona [December 10, 2018]



Russian Spacewalkers Complete Crew Vehicle Inspection

ROSCOSMOS – Soyuz MS-09 Mission patch / EVA – Extra Vehicular Activities patch.

December 11, 2018

Expedition 57 Flight Engineers Oleg Kononenko and Sergey Prokopyev of Roscosmos completed a spacewalk lasting 7 hours and 45 minutes.

Image above: Spacewalker Oleg Kononenko is on the Strela boom getting ready for inspection work on the Soyuz crew vehicle. Image Credit: NASA TV.

The two cosmonauts opened the hatch to the Pirs docking compartment to begin the spacewalk at 10:59 a.m. EST. They re-entered the airlock and closed the hatch at 6:44 p.m. EST.

Soyuz MS-09 inspected by cosmonauts

During the spacewalk, the two examined the external hull of the Russian Soyuz MS-09 spacecraft attached to the space station, took images, and applied a thermal blanket. They also retrieved science experiments from the Rassvet module before heading back inside.

It was the 213th spacewalk in support of International Space Station assembly, maintenance and upgrades, the fourth for Kononenko, and the second for Prokopyev.

Image above: A pair of empty Orlan spacesuits are seen inside the Pirs Docking Compartment airlock where cosmonauts stage Russian spacewalks. Image Credit: NASA.

Prokopyev, NASA astronaut Serena Auñón-Chancellor, and ESA (European Space Agency) astronaut Alexander Gerst are scheduled to depart the station in the Soyuz MS-09 at 8:42 p.m. Dec. 19, returning home to Earth after a six-and-half-month mission.

Related links:

Pirs docking compartment: https://www.nasa.gov/mission_pages/station/structure/elements/pirs-docking-compartment

213th spacewalk: http://www.nasa.gov/mission_pages/station/spacewalks

Soyuz MS-09: https://www.nasa.gov/feature/soyuz-launches-arrivals-and-departures

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), Video, Text, Credits: NASA/Mark Garcia/NASA TV/SciNews.

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NASA’s First Stellar Observatory, OAO 2, Turns 50

NASA – Orbiting Astronomical Observatory (OAO) 2 patch.

Dec. 11, 2018

At 3:40 a.m. EST on Saturday, Dec. 7, 1968, just three weeks before the highly anticipated launch of Apollo 8 and the first crewed flight to the Moon, an Atlas-Centaur rocket carrying NASA’s heaviest and most ambitious unpiloted satellite at the time blasted into the sky from Launch Complex 36B at Cape Canaveral Air Force Station, Florida.

Formally known as the Orbiting Astronomical Observatory (OAO) 2 and nicknamed Stargazer, it would become NASA’s first successful cosmic explorer and the direct ancestor of Hubble, Chandra, Swift, Kepler, FUSE, GALEX and many other astronomy satellites.

OAO 2 provided the first orbital stellar observations in ultraviolet light, shorter than wavelengths in the visible range spanning 3,800 (violet) to 7,500 (red) angstroms. Much of UV light is screened out by the atmosphere and unavailable to ground-based telescopes. Stargazer’s experiments made nearly 23,000 measurements, showed that young, hot stars were hotter than theoretical models of the time indicated, confirmed that comets are surrounded by vast clouds of hydrogen and discovered a curious feature of the interstellar medium that would take decades to understand.

“OAO 2 was a learning experience,” said Nancy Grace Roman, the first chief of astronomy in the Office of Space Science at NASA Headquarters, Washington. “We had to learn how to point a telescope to a single object and hold it there for a half hour or so.” This makes OAO 2 the ancestor of all space telescopes that can point to a given spot on the sky and track it for an extended period.

Seas of Infinity: OAO 2’s 50th Anniversary

Video above: Watch James Kupperian Jr., the project scientist for NASA’s Orbiting Astronomical Observatories, explain the Stargazer (OAO 2) satellite and its instruments in this excerpt from “Seas of Infinity,” a 1968 NASA film about the mission. Image Credit: NASA.

The feat proved much harder to accomplish than anyone had expected a decade earlier, at the outset of the program. But the development of star trackers — small telescopes located around the spacecraft that lock onto appropriate guide stars — and associated control software enabled extended UV observations that were previously impossible.

Prior to OAO 2, ultraviolet observations of stars were acquired by suborbital sounding rockets that collect data for only five minutes each flight as they arc above much of the atmosphere. By 1968, it was estimated that sounding rockets had captured a total of three hours of stellar UV measurements in some 40 flights. OAO 2 could collect more data than this in a single day.

In June 1958, the National Academy of Science established the 15-member Space Science Board, chaired by Lloyd Berkner, to help advise the “possible new civilian space agency” — NASA, which was established the following month when the National Aeronautics and Space Act was signed into law. After the panel’s first meeting, Berkner contacted hundreds of U.S. scientists for recommendations on experiments that could be performed by a satellite with a modest payload.

At the end of the year, James Kupperian Jr., a physicist at the Naval Research Laboratory in Washington, first used “Orbiting Astronomical Observatories” in an outline of the project. The name stuck. In 1959, he moved to NASA’s Goddard Space Flight Center in Greenbelt, Maryland, to become chief of its astrophysics branch and serve as project scientist for all four OAO missions.

Image above: Technicians in a clean room at NASA’s Kennedy Space Center in Cape Canaveral, Florida, check out the Orbiting Astronomical Observatory 2 before the mission’s Dec. 7, 1968, launch. The white conical structures visible near the top of the spacecraft are two of its six star trackers, small telescopes that lock onto appropriate guide stars to keep the instruments on target. Image Credit: NASA.

Two astronomers who responded to Berkner’s request had already determined that ultraviolet observations of stars should be the initial focus for orbital astronomy. The first was Fred Whipple, director of the Smithsonian Astrophysical Observatory in Cambridge, Massachusetts, who became the principal investigator for OAO 2’s Project Celescope (from “celestial telescope”). The experiment used four television cameras to make two-degree-square images of the sky in UV wavelengths between 1,200 and 3,250 angstroms.

The other scientist was Arthur Code, a professor of astronomy at the University of Wisconsin-Madison and director of its Washburn Observatory. Code became the principal investigator on the Wisconsin Experiment Package (WEP), a suite of seven telescopes. Four were designed to measure the UV brightness of stars from 1,330 to 4,250 angstroms, and a fifth, operating from 2,130 to 3,330 angstroms, was optimized for measuring the brightness of extended objects like nebulosity. Two scanning spectrometers recorded target spectra from 1,050 to 3,800 angstroms in 100 angstrom steps and at different resolutions.

“It’s kind of interesting that this project grew out of an institution that had never done photographic astronomy,” notes Jordan Marché II, an adjunct professor of astronomy at the University of Wisconsin, Madison. At the time, imaging, processing and measuring photographic plates was a typical aspect of astronomical work, but Code and his colleagues emphasized photometric studies over photography. “They were in this completely different mode of thinking about doing research,” Marché said.

Both experiments were mounted back-to-back within the 4,436-pound (2,012 kilogram) spacecraft and looked out opposite ends, taking turns viewing the universe.

The first WEP flew aboard OAO 1 on April 8, 1966, along with X-ray and gamma-ray experiments from Lockheed, MIT and Goddard. Just seven minutes after separation from its rocket, the spacecraft began experiencing problems in its power supply, including high-voltage arcing in the star trackers. After three days and 20 orbits, controllers terminated the mission without activating any of the experiments.

Take a “Swift” Tour of the Andromeda Galaxy

Video above: Take a tour of the best-ever UV image of our neighboring Andromeda Galaxy (M31), the closest large spiral to our own. Using its Ultraviolet/Optical Telescope, NASA’s Neil Gehrels Swift Observatory acquired 330 images in three UV colors. Some 20,000 ultraviolet sources are visible here, including M32, a small galaxy in orbit around M31. Dense clusters of hot, young, blue stars light up the disk beyond the galaxy’s smooth, redder central bulge. M31 is located 2.5 million light-years away. Video Credits: NASA/Swift/Stefan Immler (Goddard) and Erin Grand (University of Maryland, College Park).

OAO 2 fared much better, continuing to work until it was shut down in February 1973. Issues with the Celescope — primarily a gradual loss of sensitivity in its modified TV tube detectors, called uvicons — resulted in the experiment being turned off in April 1970. By then, the Celescope had captured some 8,500 images across 10 percent of the sky, and Whipple’s team ultimately published a catalog of 5,068 UV stars.

The WEP experienced fewer problems. Some weeks after launch, a calibration source in the nebula photometer stuck in place, allowing no further data to be returned from that telescope. But while the filters in the other telescopes showed some degradation in orbit, the instruments performed well and were functioning when the spacecraft was shut down.

In addition to providing important UV data on some 1,200 stars, the WEP also observed planets, galaxies and comets. One of its most striking finds occurred in early 1970, when the instrument observed comet Tago-Sato-Kosaka, which had recently rounded the Sun and was headed back out into deep space. Observations showed the comet was surrounded by a UV-emitting cloud of hydrogen bigger than the Sun, dwarfing the comet’s visible structure; a similar feature was seen around comet Bennett later that year. These findings confirmed earlier predictions based on the idea that a comet’s tiny solid nucleus was largely made of frozen water. Solar ultraviolet light breaks up water molecules streaming off the icy nucleus, resulting in a sparse but vast envelope of hydrogen atoms that scatters UV sunlight.

Image above: An illustration of OAO 2, nicknamed Stargazer, in orbit around Earth. Image Credit: NASA.

One of the most interesting results from OAO 2 involved interstellar extinction, a measure of the way matter between the stars absorbs and scatters light. The WEP showed there was a narrow extinction “bump” — that is, an increase in the way UV light was absorbed or scattered — centered at about 2,175 angstroms. Early speculation suggested that this feature may represent evidence for graphite dust grains. But theorists have introduced more exotic possibilities in the decades since, including nanodiamonds, graphite “onions,” molecules called polycyclic aromatic hydrocarbons (PAHs) and fullerenes, large, hollow soccer-ball-shaped molecules formed by carbon atoms.

“The problem is that many of the exotic forms discussed are not likely to be sufficiently abundant in interstellar space,” said John Bradley, a researcher at the University of Hawaii at Manoa who has been intrigued by the UV bump for 20 years. Bradley and his colleagues identified a similar spectral feature from PAHs embedded within interplanetary dust particles. “PAHs are everywhere,” he said, “and they are most likely the source of the bump, possibly with the addition of closely related fullerene-like molecules.”

Related links:

GALEX (Galaxy Evolution Explorer): http://www.nasa.gov/mission_pages/galex/index.html

Hubble Space Telescope (HST): https://www.nasa.gov/mission_pages/hubble/main/index.html

Swift: http://www.nasa.gov/mission_pages/swift/main/index.html

NASA History: https://www.nasa.gov/topics/history/index.html

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

Greetings, Orbiter.chArchive link

The complex history of Earth’s magnetic reversals…

The complex history of Earth’s magnetic reversals http://www.geologypage.com/2018/12/the-complex-history-of-earths-magnetic-reversals.html

Alaska earthquakes offer new insight into improving hazard…

Alaska earthquakes offer new insight into improving hazard assessment http://www.geologypage.com/2018/12/alaska-earthquakes-offer-new-insight-into-improving-hazard-assessment.html

Scientists brew lava and blow it up to better understand…

Scientists brew lava and blow it up to better understand volcanoes http://www.geologypage.com/2018/12/scientists-brew-lava-and-blow-it-up-to-better-understand-volcanoes.html

Life in Deep Earth totals 15 to 23 billion tons of carbon —…

Life in Deep Earth totals 15 to 23 billion tons of carbon — hundreds of times more than humans http://www.geologypage.com/2018/12/life-in-deep-earth-totals-15-to-23-billion-tons-of-carbon-hundreds-of-times-more-than-humans.html

Tiny Australian wallaby the last living link to extinct giant…

Tiny Australian wallaby the last living link to extinct giant kangaroos http://www.geologypage.com/2018/12/tiny-australian-wallaby-the-last-living-link-to-extinct-giant-kangaroos.html

Scientists discover how birds and dinosaurs evolved to dazzle…

Scientists discover how birds and dinosaurs evolved to dazzle with colourful displays http://www.geologypage.com/2018/12/scientists-discover-how-birds-and-dinosaurs-evolved-to-dazzle-with-colourful-displays.html

Researchers create tiny droplets of early universe matter

Researchers have created tiny droplets of the ultra-hot matter that once filled the early universe, forming three distinct shapes and sizes: circles, ellipses and triangles.

Researchers create tiny droplets of early universe matter
Visualization of expanding drops of quark gluon plasmas in three geometric shapes
[Credit: Javier Orjuela Koop]

The study, published in Nature Physics, stems from the work of an international team of scientists and focuses on a liquid-like state of matter called a quark gluon plasma. Physicists believe that this matter filled the entire universe during the first few microseconds after the Big Bang when the universe was still too hot for particles to come together to make atoms.

CU Boulder Professor Jamie Nagle and colleagues on an experiment known as PHENIX used a massive collider at Brookhaven National Laboratory in Upton, New York, to recreate that plasma. In a series of tests, the researchers smashed packets of protons and neutrons in different combinations into much bigger atomic nuclei.

They discovered that, by carefully controlling conditions, they could generate droplets of quark gluon plasma that expanded to form three different geometric patterns.

“Our experimental result has brought us much closer to answering the question of what is the smallest amount of early universe matter that can exist,” Nagle said.

Researchers from CU Boulder and Vanderbilt University lead the data analysis efforts for the PHENIX experiment.

Scientists first started studying such matter at Brookhaven’s Relativistic Heavy Ion Collider (RHIC) in 2000. They crashed together the heavy nuclei of gold atoms, generating temperatures of trillions of degrees Celsius. In the resulting boil, quarks and gluons, the subatomic particles that make up all protons and neutrons, broke free from their atomic chains and flowed almost freely.

Researchers create tiny droplets of early universe matter
Graphic showing how atomic collisions between different starting ingredients expand over time to produce plasmas in
distinct shapes. The top collision was generated by slamming a single proton into a gold atom; the middle from a collision
between a deuteron and a gold atom; and the bottom from a collision between helium-3 and a gold atom
[Credit: PHENIX, Nature 2018]

Several years later, another group of researchers reported that they seemed to have created a quark gluon plasma not by slamming together two atoms, but by crashing together just two protons.

That was surprising because most scientists assumed that lone protons could not deliver enough energy to make anything that could flow like a fluid.

Nagle and his colleagues devised a way to test those results in 2014: If such tiny droplets behaved like liquid, then they should hold their shape.

As he explained, “Imagine that you have two droplets that are expanding into a vacuum. If the two droplets are really close together, then as they’re expanding out, they run into each other and push against each other, and that’s what creates this pattern.”

In other words, if you toss two stones into a pond close together, the ripples from those impacts will flow into each other, forming a pattern that resembles an ellipse. The same could be true if you smashed a proton-neutron pair, called a deuteron, into something bigger, Nagle and Romatschke reasoned. Likewise, a proton-proton-neutron trio, also known as a helium-3 atom, might expand out into something akin to a triangle.

And that’s exactly what the PHENIX experiment found: collisions of deuterons formed short-lasting ellipses, helium-3 atoms formed triangles and a single proton exploded in the shape of a circle.

The results, the researchers said, could help theorists better understand how the universe’s original quark gluon plasma cooled over milliseconds, giving birth to the first atoms in existence.

The new study includes co-authors from 65 institutions. Co-authors from CU Boulder include postdoctoral researchers Ron Belmont and Darren McGlinchey and graduate student Javier Orjeula-Koop, all in physics.

Author: Daniel Strain | Source: University of Colorado at Boulder [December 10, 2018]



Banned toxins passed from mother to young in European dolphins

Dolphins in the northern Adriatic contain high levels of PCBs – highly toxic chemicals banned in the 1970s and 1980s – and are passing the pollutant to their young, according to new research led by a marine scientist at the University of St Andrews.

Banned toxins passed from mother to young in European dolphins
Credit: Tilen Genov/ University of St Andrews

An international team of researchers evaluated PCB and other organochlorine contaminants in bottlenose dolphins (Tursiops truncatus) living in the Gulf of Trieste (northern Adriatic Sea), the northernmost part of the Mediterranean Sea and one of the most human-impacted areas in the Mediterranean.
They found that, overall, 87.5% of dolphins had PCB concentrations above the toxicity threshold for the onset of physiological effects in marine mammals, while 65.6% had concentrations above the highest threshold published for marine mammals based on reproductive impairment in seals. Such high contaminant levels are of concern, particularly in combination with other threats to dolphins, including bycatch in fisheries, disturbance by boat traffic, and prey depletion.

The research, published in the journal Science of the Total Environment, involved Morigenos – Slovenian Marine Mammal Society (Slovenia), the Sea Mammal Research Unit at the University of St Andrews (UK), the Zoological Society of London’s Institute of Zoology (UK), the Centre for Environment, Fisheries and Aquaculture Science (CEFAS, UK) and the Institute of Marine Sciences of the Italian National Research Council (Italy).

Banned toxins passed from mother to young in European dolphins
Credit: Genov et al, Morigenos – Slovenian Marine Mammal Society (Slovenia)

Tilen Genov, lead author of the study and a Ph.D. student at the University of St Andrews, said:

“We have been studying these dolphins for over 16 years, so we know most of them well. Through long-term re-sighting histories of identified individuals, we were able to link PCB levels in individual dolphins to parameters such as sex, reproductive output and social group membership.

“The research showed that males have significantly higher pollutant concentrations than females. This is because females offload a substantial amount of their toxicological burden to their young through gestation and lactation.

Banned toxins passed from mother to young in European dolphins
Credit: Tilen Genov/ University of St Andrews

“That is also why females that have not yet had calves had significantly higher concentrations than those that had previously produced at least one calf. Such results are expected based on our knowledge of mammal physiology, but it is not very common to demonstrate this phenomenon in wild whales and dolphins.”
Dr. Paul Jepson, co-author of the study and specialist wildlife veterinarian at the Zoological Society of London’s Institute of Zoology, said:

“This is another study showing high or very high levels of a very toxic and persistent pollutant – PCBs – in European dolphins. PCBs have the ability to cause diseases like cancer and can also suppress reproduction.”

Source: University of St Andrews [December 10, 2018]




https://t.co/hvL60wwELQ — XissUFOtoday Space (@xufospace) August 3, 2021 Жаждущий ежик наслаждается пресной водой после нескольких дней в о...