суббота, 6 июля 2019 г.

Actin Up Inside every cell is a dynamic biological scaffold…

Actin Up

Inside every cell is a dynamic biological scaffold called the cytoskeleton, which needs to rapidly react and remodel itself as a cell changes shape to move or divide. The struts of the cytoskeleton are made from small, blobby actin proteins that self-assemble into long chains known as filaments, which grow and shrink as actin molecules are added or removed. These fine actin filaments form two different types of structures inside cells: thick, sturdy cables in the presence of a protein called WASp or spidery networks if formin proteins are nearby. However, much less is known about the role of another protein known as Arp2/3. Gradually increasing the amounts of Arp2/3 in the mix trigger the growth of WASp-based chunky cables (top row left to right) but have no effect on the spindly formin formations (bottom), revealing important insights into the molecular builders responsible for constructing the cytoskeleton’s component parts.

Written by Kat Arney

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What’s happening to Greenland’s ice?

ESA — European Space Agency patch.

6 July 2019

Heatwave conditions catapulted Greenland into an early Arctic summer in June, prompting widespread melting across its icesheet surface, according to researchers at the Danish Meteorological Institute.

Although unusually early, this weather-related event is not unprecedented, according to climate scientist Dr Ruth Mottram, who has published a comprehensive assessment that details major longer-term changes occurring across the planet’s second largest icesheet, in the journal Remote Sensing.

Meltwater lake

The research, involving scientists from DMI, the Technical University of Denmark and the Geological Survey of Denmark and Greenland, combined 30 years of satellite observations of the icesheet’s surface height, mass and movement with climate model output. Collectively this work provides a ‘health check on the icesheets current status and helps to establish the extent of ice loss due to surface melt or from other ocean processes, such as iceberg calving.

An average 255 gigatonnes of ice was lost each year from 2003 to 2016, according to the research team’s findings.

Worringly, the loss of ice shows a marked three-fold acceleration (83 Gt) compared to the preceding decade and consistent with similar studies at the North and South poles, and a potential concern for the international community.

Loss of land ice is a potential indicator of climate change and contributes directly to sea level rise, posing a risk to people living near the coast across the world.

“The Greenland losses have raised sea level by around half a millimeter each year over the observed period,” explains Dr Mottram. She also emphasises the importance of continuing monitoring as scientists are still yet to fully understand the reasons for interannual variability that they observe.

Changing Greenland icesheet height 1995-2017

Almost all of the ice loss was due to changes in surface mass budget, with thinning found virtually everywhere. At some locations, the icesheet surface decreased by over two and a half metres per year between 1995 and 2017 based on measurements using space-borne radar altimeters.

The researchers point to increased melting and changes in snowfall rates for the decrease.

“If an icesheet is to maintain its mass balance, or volume, we would expect to see the height increase at its centre due to snow accumulation. It is striking how this pattern has changed when comparing the early 1990s to the last few years,” explains Dr Mottram.

The rate of ice flow and iceberg calving of glaciers can also be measured from Space, with the study finding that all but one from a representative sample of 28 Greenland glaciers had substantially retreated since the 1990s.

Such changes were found in areas around Jakobshavn Isbrae in western Greenland and Helheim glacier in south east Greenland with the increase in ice flow pulling more ice out of the interior, contributing to a thinning of the icesheet.

The observational datasets used in this study have been developed through the European Space Agency’s Climate Change Initiative. Covering 21 key components of the Earth climate system, including information on the cryosphere and the Greenland icesheet, the continuous and long-term time series are generated by merging historic satellite missions with today’s current satellites, including the Copernicus Sentinels. Referred to as Essential Climate Variables, they provide the empirical evidence of a changing climate and support policy and decision-makers to address the consequences.

Ice velocity maps of Greenland

This latest study used these observations to validate and identify improvements to the existing climate and icesheet computer models, used to simulate the icesheet’s current state and predict how it may change into the future.

Despite huge strides being made in understanding the icesheet, the models and observations did not fully agree in certain areas, such as Southern Greenland, nor were the simulations able to fully capture the variability in year to year ice loss.

The authors emphasise the importance of continuing accurate monitoring of the icesheet to help investigate and model its dynamic processes and point to the Copernicus Sentinel satellites as game-changers.

“With Copernicus Sentinel-1 and -3, we are moving from only being able to take a short snapshot of icesheet flow speeds or calving front changes beginning to be able to monitor the Greenland icesheet remotely, in almost real time.

“We now get consistent, weekly repeat, and with such a richness of data we can more accurately understand how Greenland is responding to a changing environment.”

Related links:

Remote Sensing: https://www.mdpi.com/2072-4292/11/12/1407

Observing the Earth: http://www.esa.int/Our_Activities/Observing_the_Earth

Space for our climate: http://www.esa.int/Our_Activities/Observing_the_Earth/Space_for_our_climate

Climate Change Initiative: http://cci.esa.int/

Sentinel-1: http://www.esa.int/Our_Activities/Observing_the_Earth/Copernicus/Sentinel-1

Sentinel-3: http://www.esa.int/Our_Activities/Observing_the_Earth/Copernicus/Sentinel-3

Copernicus: http://www.esa.int/Our_Activities/Observing_the_Earth/Copernicus

Images, Text, Credits: ESA/Nasa/Jim Yungel/Mottram et al.

Greetings, Orbiter.chArchive link

Tomnavrie Prehistoric Stone Circle, Aberdeenshire, 6.7.19.

Tomnavrie Prehistoric Stone Circle, Aberdeenshire, 6.7.19.

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An infrared close up of the moon

A first-of-its-kind camera developed in partnership between CU Boulder and Ball Aerospace will soon be landing on the moon.

An infrared close up of the moon
Peaks within the moon’s Tycho Crater [Credit: NASA Goddard/
Arizona State University]

NASA announced today that it has selected the scientific instrument, called the Lunar Compact Infrared Imaging System (L-CIRiS), for its Commercial Lunar Payload Services program.

The camera will ride along with one of three robotic landers that will touch down on the lunar surface in the next several years—a key step in NASA’s goal of sending people back to the moon by 2024.

Planetary scientist Paul Hayne, who is leading the development of the instrument, said that the goal is to collect better maps of the lunar surface to understand how it formed and its geologic history. L-CIRiS will use infrared technology to map the temperatures of the shadows and boulders that dot the lunar surface in greater detail than any images to date.

And, Hayne added, the team believes that similar cameras could hitch a ride on many more future moon missions.

«In L-CIRiS, we have designed a cutting-edge instrument in a very small package,» said Hayne, an assistant professor at CU Boulder’s Laboratory for Atmospheric and Space Physics (LASP). «We can envision including an infrared camera based on L-CIRiS on nearly every lunar mission going forward, for both science and reconnaissance.»

Colorado-based Ball Aerospace will build the instrument, and researchers from the University of Central Florida and the University of California, Los Angeles will contribute to the project.

«Collecting better data on the surface of the moon will be crucial step in understanding not just how this body evolved but also in paving the way for the return of American astronauts,» said Daniel Baker, director of LASP. «This project highlights how scientists at LASP are partnering with top engineers and industry partners to lead the way for the next generation of human space exploration.»

Touch down

The commercial lander program is a critical component of that next wave of lunar voyages. In May, NASA picked three companies—Astrobotic, Intuitive Machines and Orbit Beyond—to send robotic spacecraft to the moon as early as 2020.

An infrared close up of the moon
A simulation of the level of detail that L-CIRiS’s infrared camera will reveal
of the moon’s surface [Credit: Ball Aerospace]

Those missions will, in part, test out possible landing sites for human missions in the following years, from craters on the near side of the moon to possible ice deposits near the lunar poles.

Hayne isn’t sure where on the moon L-CIRiS will be heading to yet. But the instrument will pack a big punch once it arrives.

That’s because the infrared camera will sit directly on top of one of the commercial landers and will scan the area around where it comes down, beginning a few feet away from the lander and extending to the horizon. The images will enable scientists to determine what the materials at the landing site are made of and how dense they are.

Such detailed images can also help to keep astronauts safe as they land their own spacecraft at similar sites.

«Data from L-CIRiS will help plan future lander, rover and astronaut missions by identifying hazardous rocks and determining the density of the lunar soil,» said Hayne, also of the Department of Astrophysical and Planetary Sciences.

And it could map out what is, perhaps, the moon’s most valuable resource: water.

Scientists know that ice exists on the moon’s surface, usually in the shadows cast by craters near the poles. But they’re not sure what conditions are most conducive to forming this lunar ice. L-CIRiS’s data may help researchers to develop a more complete picture of how and where water collects on the moon.

Hayne says that he’s also thrilled to see his work become a small piece of what he hopes will be a renewed national excitement for exploring space.

«I think going back to the moon and building a permanent presence there will inspire people,» Hayne said. «I think it will lead to a lot of little girls and boys pursuing careers in science.»

Author: Daniel Strain | Source: University of Colorado at Boulder [July 01, 2019]



Comet and asteroid experts agree on natural origin for Oumuamua

A team of international asteroid and comet experts now agree that Oumuamua, the first recorded interstellar visitor, has natural origins, despite previous speculation by some other astronomers that the object could be an alien spacecraft sent from a distant civilization to examine our star system.

Comet and asteroid experts agree on natural origin for Oumuamua
This artist’s impression shows the first interstellar object discovered in the Solar System, Oumuamua. Observations
made with the NASA/ESA Hubble Space Telescope, CFHT, and others, show that the object is moving faster than
predicted while leaving the Solar System. The inset shows a colour composite produced by combining 192
 images obtained through three visible and two near-infrared filters totaling 1.6 hours of integration
on October 27, 2017, at the Gemini South telescope [Credit: ESA/Hubble, NASA, ESO/
M. Kornmesser, Gemini Observatory/AURA/NSF]

A review of all the available evidence by an international team of 14 experts, including Robert Jedicke and Karen Meech of the University of Hawaii’s Institute for Astronomy (IfA), strongly suggests that Oumuamua has a purely natural origin. The research team reported its findings in  Nature Astronomy.

«While Oumuamua’s interstellar origin makes it unique, many of its other properties are perfectly consistent with objects in our own solar system,» said Jedicke. Oumuamua’s orbit and its path through our solar system matches a prediction published in a scientific journal by Jedicke and his colleagues half a year before Oumuamua’s discovery.

«It was exciting and exhausting to coordinate all the Oumuamua observations with my co-authors from all around the world,» said Meech. «It really was a 24-hour-a-day effort for the better part of two months. In that paper we established that Oumuamua rotates once in about seven hours and that it had a red color similar to many objects locked within our own solar system.»

The work showed that Oumuamua must have an extremely elongated shape, like a cigar or maybe a frisbee, unlike any known object in our solar system based on changes in its apparent brightness while it rotated.

Meech and other UH researchers were essential to another paper published in Nature a year ago that indicated Oumuamua is accelerating along its trajectory as it leaves our solar system. This behavior is typical of comets but astronomers have found no other visual evidence of the gas or dust emissions that create this acceleration.

«While it is disappointing that we could not confirm the cometary activity with telescopic observations, it is consistent with the fact that Oumuamua’s acceleration is very small and must therefore be due to the ejection of just a small amount of gas and dust,» Meech explained.»

«We have never seen anything like Oumuamua in our solar system,» said Matthew Knight of the University of Maryland. «Our preference is to stick with analogs we know, unless, or until we find something unique. The alien spacecraft hypothesis is a fun idea, but our analysis suggests there is a whole host of natural phenomena that could explain it.»

The team of astronomers hailing from the U.S. and Europe met late last year at the International Space Science Institute (ISSI) in Bern, Switzerland, to critically assess all the available research and observations on Oumuamua and will meet again later this year. Their first priority was to determine whether there is any evidence to support the hypothesis that Oumuamua is a spacecraft built by an alien civilization.

«We put together a strong team of experts in various different areas of work on Oumuamua. This cross-pollination led to the first comprehensive analysis and the best big-picture summary to date of what we know about the object,» Knight explained. «We tend to assume that the physical processes we observe here, close to home, are universal. And we haven’t yet seen anything like Oumuamua in our solar system. This thing is weird and admittedly hard to explain, but that doesn’t exclude other natural phenomena that could explain it.»

The ISSI team considered all the available information in peer-reviewed scientific journals and paid special attention to the research published by IfA researchers. In particular, Meech’s research paper in the journal Nature first reported on Oumuamua’s discovery and characteristics in December 2017, just two months after the unusual object was identified by Pan-STARRS1 (Panoramic Survey Telescope and Rapid Response System) on Haleakala.

The ISSI team considered a number of mechanisms by which Oumuamua could have escaped from its home system. For example, the object could have been ejected by a gas giant planet orbiting another star. According to this theory, Jupiter created our own solar system’s Oort cloud, a population of small objects only loosely gravitationally bound to our Sun in a gigantic shell extending to about a third of the distance to the nearest star. Some of the objects in our Oort cloud eventually make it back into our solar system as long period comets while others may have slipped past the influence of the Sun’s gravity to become interstellar travelers themselves.

The research team expects that Oumuamua is just the first of many interstellar visitors discovered passing through our solar system, and they are collectively looking forward to data from the Large Synoptic Survey Telescope (LSST) that is scheduled to be operational in 2022. The LSST, located in Chile, may detect one interstellar object every year and allow astronomers to study the properties of objects from many other solar systems.

While ISSI team members hope that LSST will detect more interstellar objects, they think it is unlikely that astronomers will ever detect an alien spacecraft passing through our solar system and they are convinced that Oumuamua was a unique and extremely interesting but completely natural object.

Source: University of Hawaii at Manoa [July 01, 2019]



‘Gentle recovery’ of Brazil’s leatherback turtles

Brazil’s leatherback turtles are making a «gentle recovery» after 30 years of conservation efforts, new research shows.

'Gentle recovery' of Brazil's leatherback turtles
Leatherback turtle in Brazil [Credit: Banco de Imagens Projeto TAMAR]

Scientists studied nesting sites in the state of Espírito Santo in eastern Brazil — the only place in the south-west Atlantic where leatherbacks regularly nest. Data on this small population from 1988-2017 showed the average number of nests rose from 25.6 in the first five years of the period to 89.8 in the final five years.

The researchers, from the University of Exeter and Brazilian sea turtle conservation programme TAMAR-ICMBio, believe local conservation efforts have contributed to this increase. But they say conservation of this population is still a concern due to climate change, pollution, coastal development and «bycatch» (accidental catch by humans fishing).

«The numbers vary year by year, but overall we have seen an increase in the number of leatherback nests in Espírito Santo,» said Dr Liliana Poggio Colman, of the Centre for Ecology and Conservation on the Exeter’s Penryn Campus in Cornwall.

«This gentle recovery is probably due, at least in part, to local conservation efforts started by Projeto TAMAR in the 1980s. Our study revealed a significant decrease in the size of the turtles breeding on these beaches, suggesting that new females are joining the breeding population.»

'Gentle recovery' of Brazil's leatherback turtles
Liliana Poggio Colman with a leatherback turtle in Brazil
[Credit: University of Exeter]

Dr Poggio Colman, who had a scholarship from the programme Science Without Borders, funded by the Brazilian government, added: «We are encouraged by what we have found, but this is a small population — fewer than 20 nesting females per year, each laying several clutches — so their conservation will remain a concern.»

Throughout the study period, nests were concentrated in the southern part of the 100-mile (160km) study area, with the protection of core nesting areas being key for the effective conservation of this population.

Professor Brendan Godley, who was one of Dr Poggio Colman’s PhD supervisors, added: «It was a great pleasure to help facilitate this collaborative work in Brazil.

«By chance, the team was in the field when a major spill of waste mining material impacted in the area in 2015. Average hatching success has, however, remained fairly steady at about 66%.»

The paper is published in the journal Endangered Species Research.

Source: University of Exeter [July 01, 2019]



Whales targeted by Japan face extinction threat

One of three species Japan has targeted in resuming commercial whaling Monday is threatened with extinction, and sub-populations of the other two are severely depleted as well, according to experts.

Whales targeted by Japan face extinction threat
One of three species Japan has targeted in resuming commercial whaling is threatened with extinction,
and sub-populations of the other two are severely depleted as well
[Credit: Kazuhiro Nogi/AFP]

After pulling out of the International Whaling Commission (IWC) at the end of last year, Japan announced it would allow 227 of the giant sea mammals to be harpooned within its territorial waters—extending 200 nautical miles (370 kilometres) from its coast—before the end of December.

The commission’s 1986 moratorium on whaling forbids all whaling, though a trio of countries, including Japan, flouted the ban through loopholes while remaining within the IWC.

Japan’s new self-arrogated quota—which could be renewed or changed next year—includes 150 Bryde’s, 52 minke and 25 sei whales.

One of these species, the sei, is listed at «endangered» on the International Union of the Conservation of Nature’s Red List, which has assessed the conservation status of some 100,000 animals and plants.

The sei—at 20 metres (645 feet), the biggest of whales after the blue and the fin—was the main target of Japan’s ostensibly «scientific» whaling from the early 2000s until 2017.

The Red List classifies Bryde’s and minke whales «of least concern,» meaning they are not currently threatened with extinction.

But these assessments obscure a more nuanced reality that could spell trouble for sub-groups of the species as well, according to Justin Cooke, a long-standing member of the IWC’s scientific committee and a member of the IUCN’s Cetacean Group.

Whales targeted by Japan face extinction threat
Whales targeted in Japan’s first commercial whaling season since the country walked
out of the International Whaling Commission [Credit: John Saeki/AFP]

«There are two types of minke whale exploited off the coast of Japan,» he told AFP.

«The one found in coastal waters—in the Sea of Japan, the East China Sea and the Yellow Sea—is quite severely depleted due to a long history of catches by Japan and South Korea.»

Besides those targeted by whalers, others die after getting caught up in netting set for fish, he explained.

Known as the «J stock», the coast-hugging minke (Balaenoptera acutorostrata) are highly unusual among baleen, or filter-feeding, whales because they breed during the summer rather than the winter.

Surveys by Japanese and South Korean fisheries agencies have estimated their numbers at about 1,500, Cooke said in an interview.

The more plentiful «O stock» minke—which breed in summer and number about 25,000—are found further north in the Sea of Okhotsk, in Russian waters.

As with other types of whales, including orca, sub-populations of the same species can develop highly distinct behaviour patterns, which has led some biologists to describe these differences as «cultural».

Whales targeted by Japan face extinction threat
Number of whales killed each year by country despite the international moratorium
on commercial whaling introduced in 1986 [Credit: Simon Malfatto/AFP]

There are two known sub-species of the larger Bryde’s whales—also filter feeders—that grow up to 17 metres (55 feet) in length.

Japan stopped hunting Bryde’s in 1987, but re-authorised yearly catches in international waters of 50 individuals starting in 2000, again for supposedly «scientific» research.

The North Pacific population—found mostly in the middle range of Japan’s exclusive economic zone—was recently estimated at just over 26,000 by the IWC’s scientific committee.

The other sub-species is found in Japan’s southern waters and supports a local whale-watching industry. Also known as Eden’s whale, they number just under 170, according to a 20-year old stocktake, Cooke said.

For the endangered Sei whale, experts disagree on how to characterise its population.

«Japanese scientists insist that there is only one (population) in the whole North Pacific,» said Cooke. «But they have only collected data from the offshore area.»

A competing hypothesis is that the region is home to five distinct populations, including one along the western coast that will now be hunted for its meat.

The latest estimate for this sub-group is about 400, Cook said.

Author: Marlowe Hood | Source: AFP [July 01, 2019]



Completion of the 2019 Ancient Akrotiri Project

The Department of Antiquities, Ministry of Transport, Communications and Works has announced the completion of the 2019 Ancient Akrotiri Project (AAP), led by the University of Leicester under the direction of Professor Simon James. The team consisted of professional excavation staff and undergraduate students from the University of Leicester’s School of Archaeology and Ancient History, in collaboration with colleagues from the Universities of Southampton, Cyprus and Athens. The excavations were conducted between 4th and 23rd April 2019, at and around the vicinity of Akrotiri-Dreamer’s Bay (Nissarouin). This excavation season marks the fifth year of work conducted by the AAP on remains in the southern coast of the peninsula, which appears to have comprised an ancient port, quarry and other facilities.

Completion of the 2019 Ancient Akrotiri Project
Akrotiri-Dreamer’s Bay (Nissarouin) [Credit: Dept. of Antiquities,
Republic of Cyprus]

Previous land archaeology seasons from 2015-2018 saw exploration of Roman (2nd-4th-cent. AD) shoreline buildings overlain by concentrations of later ceramics, largely late Roman/Byzantine (5th-7th cent.) amphorae, with 2018 also including exploration of a submerged ancient masonry breakwater and other archaeological remains on the floor of Dreamer’s Bay itself.
During April 2019, investigations on a concentration of masonry buildings on the hilltop overlooking the shoreline structures from the north were completed, as well as further survey and sample excavations of the large complex of ancient quarries at the top of the 40 metre-high scarp overlooking Dreamer’s Bay harbour.

Completion of the 2019 Ancient Akrotiri Project
Akrotiri-Dreamer’s Bay (Nissarouin) [Credit: Dept. of Antiquities,
Republic of Cyprus]

The hilltop complex, sited at a point commanding a very wide field of view from Kourion c.13km to the north, Cape Zevgari to the west and round almost to Cape Gata in the east, would have been extremely well sited both to spot approaching shipping, and to act as a landmark for vessels making landfall at Akrotiri. Structures were accidentally revealed here in the 1980s, and estimated to be of late Antique chronology. The partially exposed remains formed the starting-point for AAP investigation starting in 2017, and completed in the April 2019 season. This year the excavated area was extended by trenching both to the northern and eastern edges of the site, the western extent of the ancient rubble mound encapsulating the surviving foundations having been previously established.
The remains encountered comprised several stone-founded structures with evidence of multiple phases suggesting a fairly extended life. The north side of theDreamer’s Bay hilltop complexcomprised parallel stone foundations apparently overlain by a large ovoid structure with clay floor of uncertain purpose. Pottery, roofing materials and coins suggest occupation during the Byzantine period, to at least the sixth century, although construction during the Roman period cannot be ruled out.

Completion of the 2019 Ancient Akrotiri Project
Akrotiri-Dreamer’s Bay (Nissarouin) [Credit: Dept. of Antiquities,
Republic of Cyprus]

The team’s work in the quarry complex comprised survey of the very well-preserved traces of ancient rock-cutting, producing squared blocks and round millstones from different grades of marine conglomerate. Sample excavation was undertaken of heavily eroded masonry structures identified in the quarried landscape, which turned out to have possessed finely plastered walls with simple painted decoration. A ceramic piped water supply probably also related to this complex and provisionally dated to the Roman era (1st-4th c. AD) was recorded. The buildings overlay part of the quarrying, proving that at least some of it was earlier.

This fieldwork season has added important elements to the emerging picture of a complex commercial and industrial coastscape at Dreamer’s Bay with a history lasting several centuries.

Source: Department of Antiquities, Republic of Cyprus [July 03, 2019]



The Gaul who lost a coin in Palencia

It is only a hypothesis, but a very probable one… the coin was dropped by a Gallic soldier who was part of the auxiliary troops of the Emperor Augustus when he arrived at the wheat fields of present-day Osorno (Palencia). And more than 2,000 years later, the Dessobriga Project team, led by Margarita Torrione, professor of Hispanic History and Civilization at the University of Savoy (France), found that coin that was minted in the second half of the first century BC by Contoutos, chief of the Santoni, a tribe of southwestern Gaul (north of the Gironde estuary), and the first people defeated by Julius Caesar in the Gallic War.

The Gaul who lost a coin in Palencia
Gallic coin found at the Dessobriga site
[Credit: The Dessobriga Project]

At the same time, other finds were made, such as a large building about 50 metres in length, detected by aerial photography and currently being excavated. There are also several stelae from the pre-Roman necropolis, some engraved in the Celtiberian script. One of them bears the indigenous name of Touto: «Quite common in stelae from the Iberian Peninsula of the Middle Iron Age, whose etymology comes from the Celtic ‘touta’ meaning ‘community, tribe, clan'», Torrione says.

Underlying all this is a Vacceian settlement and later a Roman city, militarized by Rome for its privileged position as a crossroads and for its abundance of grain.

In the last third of the 1st century BC, the Cantabrian and Asturian tribes had still not submitted to imperial power. Needing supplies they frequently plundered the fertile fields of their Vacceian neighbours. When Augustus set up his camp in Segisamo (present-day Sasamón, Burgos), some 30 kilometres from Osorno, he faced a similar problem: to maintain his legions and auxiliary troops, as well as depriving the rebels of much needed provisions. For this reason, Dessobriga was attacked and subdued around 29 BC, during the preparations for the Cantabrian Wars (29-19 BC).

In 2001, owing to the construction of the Camino de Santiago Motorway, emergency excavations were carried out not far from the Las Cuestas (Osorno) hillock, which uncovered part of a settlement from the early Iron Age (8th-5th centuries BC).

The Gaul who lost a coin in Palencia
Archaeologists in Dessóbriga in the 2016 campaign
[Credit: The Dessobriga Project]

In 2013, Margarita Torrione commenced a project specifically aimed at unearthing Dessobriga, an urban centre included in the Itinerario Antonino.

«To this end, I drew up a work plan that was carried out by means of geomagnetic prospecting, with financial support from the Palencia Provincial Council, the Osorno City Council, my own funds and permission from the Junta de Castilla y León», says Torrione.

A total of 23 hectares were explored which revealed the existence of prehistoric huts (between the 8th and 5th centuries BC), a later Vacceian settlement with a markedly defensive character, later converted into an urban centre and a cremation necropolis.

The large building that is currently being excavated in the Amesetada area of the Las Cuestas hillock, corresponds to a former indigenous structure, «later renovated and reused by the Romans». This structure was likely used for grain storage and/or commerce activities. In the first decades of the 1st century AD parts of this structure were razed and covered by a wide cobblestone avenue that may correspond to the cardo maximus, a kind of great north-south road.

The Gaul who lost a coin in Palencia
Roman double-finned arrow used during the capture of Dessobriga
[Credit: The Dessobriga Project]

A large defensive wall and moat just over six metres wide defended the population from possible attacks in its most vulnerable area. The abundant archaeological material found (ceramics, fibulas, coins, weapons, marbles, along with buildings and the defensive system) certify that this territory, located between the districts of Osorno la Mayor and Melgar Fernamental in the provinces of Palencia and Burgos, was intensely occupied between the first Iron Age and the end of the second century AD, during the period of the high Roman Empire.
According to the Greek chronicler Diodorus of Sicily (1st century BC), the Vacceians were the most developed ethnic group among the neighbouring villages of the Celtiberians and occupied a 45,000 square kilometre strip of the Iberian Peninsula. They have been called the first «communists» in history, given their collectivist production system since, as Diodorus says, the harvest was shared equally among all the inhabitants. «In reality the distribution was most likely controlled by the elites, so this supposedly egalitarian economic system is far from certain,» says Torrione. Nevertheless it was their fertile fields that led them to be the targets of raids by the surrounding villages and of Rome, which ultimately meant the end of their freedom, as confirmed by the bronze coin lost by a Gallic soldier far from his home in Hispania.

A new archaeological campaign is scheduled to take place from the 5th to the 25th of August this year. For more information visit the Dessobriga Project website.

Author: Vicente G. Olaya (trsl. TANN) | Source: El Pais [July 02, 2019]



More ‘reactive’ land surfaces cooled the Earth down…

More ‘reactive’ land surfaces cooled the Earth down http://www.geologypage.com/2019/07/more-reactive-land-surfaces-cooled-the-earth-down.html

2019 July 6 8 Minute and 30 Second Eclipse Image Credit &…

2019 July 6

8 Minute and 30 Second Eclipse
Image Credit & Copyright: Bob Minor

Explanation: The total phase of the July 2nd solar eclipse lasted about 4 minutes and 30 seconds at the point of maximum eclipse. On the surface of planet Earth, that was about 600 nautical miles north of Easter Island in the Southern Pacific Ocean. But from 37,000 feet above, on a charter flight intercepting the Moon’s shadow, the Moon could be seen to completely block the Sun for about 8 minutes and 30 seconds. With a tailwind at the mid-eclipse intercept point, the plane was traveling around 488 nautical miles per hour chasing along the Moon’s shadow track. From above the clouds this wide-field image of the totally eclipsed Sun and shimmering solar corona over the wing records the spectacular view from a window seat on the sunward side of the aircraft.

∞ Source: apod.nasa.gov/apod/ap190706.html

Meteor Activity Outlook for July 6-12, 2019

       Christian Koll captured this fine fireball at 21:42 Universal Time on June 28, 2019 from Litzlham, Oberösterreich, Austria. © Christian Koll

During this period the moon reaches its first quarter phase on Tuesday July 9th. On that date the moon is located 90 degrees east of the sun and sets near 0100 local daylight saving time (LDST). This weekend the waxing crescent moon will set during the late evening hours and will not cause any problems for viewing meteor activity during the more active morning hours. The estimated total hourly meteor rates for evening observers this week is near 3 no matter your location. For morning observers the estimated total hourly rates should be near 10 as seen from mid-northern latitudes (45N) and 11 as seen from tropical southern locations (25S). The actual rates will also depend on factors such as personal light and motion perception, local weather conditions, alertness and experience in watching meteor activity. Evening rates are reduced during this period due to moonlight. Note that the hourly rates listed below are estimates as viewed from dark sky sites away from urban light sources. Observers viewing from urban areas will see less activity as only the brightest meteors will be visible from such locations.

The radiant (the area of the sky where meteors appear to shoot from) positions and rates listed below are exact for Saturday night/Sunday morning July 6/7. These positions do not change greatly day to day so the listed coordinates may be used during this entire period. Most star atlases (available at science stores and planetariums) will provide maps with grid lines of the celestial coordinates so that you may find out exactly where these positions are located in the sky. A planisphere or computer planetarium program is also useful in showing the sky at any time of night on any date of the year. Activity from each radiant is best seen when it is positioned highest in the sky, either due north or south along the meridian, depending on your latitude. It must be remembered that meteor activity is rarely seen at the radiant position. Rather they shoot outwards from the radiant so it is best to center your field of view so that the radiant lies at the edge and not the center. Viewing there will allow you to easily trace the path of each meteor back to the radiant (if it is a shower member) or in another direction if it is a sporadic. Meteor activity is not seen from radiants that are located below the horizon. The positions below are listed in a west to east manner in order of right ascension (celestial longitude). The positions listed first are located further west therefore are accessible earlier in the night while those listed further down the list rise later in the night.


Radiant Positions at 22:00 LDST

Radiant Positions at 22:00 Local Daylight Saving Time

Radiant Positions at 01:00 LDST

Radiant Positions at 1:00 Local Daylight Saving Time

Radiant Positions at 04:00 LDST

Radiant Positions at 4:00 Local Daylight Saving Time

These sources of meteoric activity are expected to be active this week.

The alpha Capricornids (CAP) are active from July 3 through August 11 with maximum activity occurring during the last week of July. The broad maximum occurs anywhere from July 25 to the 30th with visual rates usually around 3 per hour. The radiant is currently located at 18:49 (282) -15, which places it in southern Scutum, 4 degrees east of the dim star known as gamma Scuti. This radiant is best placed near midnight local standard time (LDST), when it lies on the meridian and is located highest in the sky. Hourly rates at this time should be less than 1 no matter your location. With an entry velocity of 22 km/sec., the average alpha Cap meteor would be of slow velocity.

The center of the large Anthelion (ANT) radiant is currently located at 19:52 (298) -21. This position lies in eastern Sagittarius, 8 degrees southwest of the 3rd magnitude star known as Dabih (beta¹ Capricorni). Due to the large size of this radiant, anthelion activity may also appear from western Capricornus as well as Sagittarius. This radiant is best placed near 0100 (LDST), when it lies on the meridian and is located highest in the sky. Rates at this time should be near 2 per hour as seen from mid-northern latitudes (45 N) and 3 per hour as seen from the southern tropics (S 25). With an entry velocity of 30 km/sec., the average anthelion meteor would be of slow velocity.

The Northern June Aquilids (NZC) are active from a radiant located at 20:54 (314) -04. This area of the sky is located in western Aquarius, 8 degrees west of the 3rd magnitude star known as Sadalsuud (beta Aquarii A). This radiant is best placed near 0200 LDST, when it lies on the meridian and is located highest in the sky. Hourly rates at this time should be near 2 no matter your location. With an entry velocity of 38 km/sec., the average meteor from this source would be of medium-slow velocity. An interesting fact about this source is that it may be related to the Northern delta Aquariids of August. Where and when this source ends coincides with the start and position of the Northern delta Aquariids.

The Southern June Aquilids (SZC) were discovered by G. Gartrell and W. G. Elford, in their study of Southern Hemisphere meteor streams. This stream is active from June 9 through July 17 with maximum activity occurring on July 6. The radiant is currently located at 21:22 (320) -27. This area of the sky is actually located on the border of Capricornus and Piscis Austrinus, 4 degrees south of the 4th magnitude star known as zeta Capricorni A. This radiant is best placed near 0300 LDST, when it lies on the meridian and is located highest in the sky. Hourly rates at this time are expected to be near 1 as seen from the northern hemisphere and 2 as seen from south of the equator. With an entry velocity of 39 km/sec., the average meteor from this source would be of medium-slow velocity. This source is synonymous with the Microscopiids.

The epsilon Pegasids (EPG) were discovered by Dr. Peter Brown and associates using data from the Canadian Meteor Orbit Radar (CMOR) installation. These meteors are active from July 03-23 with maximum activity occurring on July 11th. The radiant position currently lies at 21:47 (327) +12. This area of the sky lies in western Pegasus, 2 degrees north of the 2nd magnitude star known as Enif (epsilon Pegasi). These meteors are best seen near 0300 LDST when the radiant lies highest in the sky. Hourly rates are expected to be near 1 no matter your location. With an entry velocity of 28 kilometers per second, a majority of these meteors will appear to move with medium-slow velocities.

The July Pegasids (JPE) have been noticed for some time now but have had a checkered history. It has been added, dropped, and then re-added to several radiant lists. Video studies within the past 10 years have positively identified this source as an active radiant during the entire month of July. Maximum activity occurs on July 10th. The radiant is currently located at 23:02 (345) +10. This area of the sky is located in southern Pegasus, 5 degrees south of the 2nd magnitude star known as Markab (alpha Pegasi). This radiant is best placed near 0400 LDST, when it lies on the meridian and is located highest in the sky.  Rates are expected to be near 1 per hour this week no matter your location. With an entry velocity of 68 km/sec., the average meteor from this source would be of swift velocity.

The 49 Andromedids (FAN) were discovered by Željko Andreić and the Croatian Meteor Network team based on studying SonotaCo and CMN observations (SonotaCo 2007-2011, CMN 2007-2010). These meteors are active from July 6 through August 14 with maximum activity occurring on July 21. The current position of the radiant is 00:41 (010) +43. This position lies in northern Andromeda, only 1 degree north of the naked eye Andromeda Galaxy. Rates are currently expected to be less than 1 per hour no matter your location. These meteors are best seen near during the last dark hour of the night when the radiant lies highest in a dark sky.With an entry velocity of 60 km/sec., the average meteor from this source would be of swift speed.

The psi Cassiopeiids (PCA) were discovered by Zdenek Sekanina in his study of radio streams. These meteors are active from July 5 through August 7 with maximum activity occurring on July 22. The current position of the radiant is 00:39 (010) +69. This position lies in northern Cassiopeia, directly between the stars gamma Cassiopeiae and gamma Cephei. Rates are currently expected to be less than 1 per hour no matter your location. These meteors are best seen near during the last dark hour of the night when the radiant lies highest in a dark sky. With an entry velocity of 42 km/sec., the average psi Cassiopeiid meteor would be of medium speed.

The phi Piscids (PPS) were another discovery by Dr. Peter Brown and associates using data from the Canadian Meteor Orbit Radar (CMOR) installation. These meteors are active from June 8-August 02 with maximum activity occurring on July 5th. The radiant position currently lies at 01:16 (019) +26. This area of the sky lies in northeastern Pisces, 5 degrees northeast of the 4th magnitude star known as eta Andromedae. These meteors are best seen near during the last dark hour of the night when the radiant lies highest in a dark sky. Current rates should be near 2 per hour as seen from the northern hemisphere and 1 as seen from south of the equator. With an entry velocity of 67 kilometers per second, a majority of these meteors will appear to move with swift velocities.

The c-Andromedids (CAN) were discovered by Sirko Molau and Juergen Rendtel using video data from the IMO network. Activity from this source is seen from June 26 through July 27 with maximum activity occurring on July 9. The radiant currently lies at 01:46 (026) +47, which places it in northern Andromeda, 2 degrees south of the 4th magnitude star known as Nembus (51 Andromedae). This area of the sky is best seen during the last dark hour before dawn when the radiant lies highest in a dark sky. Observers in the northern hemisphere are better situated to view this activity as the radiant rises much higher in the sky before dawn compared to southern latitudes. Current rates should be near 1 per hour for observers in the northern hemisphere and less than 1 for observers in the southern hemisphere. With an entry velocity of 58 km/sec., the average meteor from this source would be of swift velocity.

The July chi Arietids (JXA) were discovered by two investigating teams in Europe using video data from European video Meteor Network Database (EDMOND), SonotaCo, 2013; and CMN, 2013. Activity from this stream is seen from July 2 through August 1 with maximum activity occurring on July 13. The radiant currently lies at 01:58 (030) +07, which places it in southeastern Pisces, 4 degrees north of the 4th magnitude star known as Alrescha (alpha  Piscium A). This area of the sky is best seen during the last dark hour before dawn when the radiant lies highest in a dark sky. Current rates are expected to be near 1 per hour during this period. With an entry velocity of 69 km/sec., the average meteor from this source would be of swift velocity.

Sporadic rates have evened out at this time with morning rates near 8 per hour and evening rates near 2 no matter your location. Evening rates are reduced during this period due to moonlight.

The list below offers the information from above in tabular form. Rates and positions are exact for Saturday night/Sunday morning except where noted in the shower descriptions.

RA (RA in Deg.) DEC Km/Sec Local Daylight Saving Time North-South
alpha Capricornids (CAP) Jul 27 18:49 (282) -15 22 01:00 <1 – <1 II
Anthelion (ANT) 19:52 (298) -21 30 02:00 2 – 3 II
Northern June Aquilids (NZC) Jul 03 20:54 (314) -04 41 03:00 2 – 2 IV
Southern June Aquilids (SZC) Jul 06 21:22 (320) -27 39 04:00 1 – 2 IV
epsilon Pegasids (EPG) Jun 15 21:07 (316) +04 33 04:00 <1 – <1 IV
July Pegasids (JPE) Jul 11 21:24 (321) +09 28 04:00 <1 – <1 IV
psi Cassiopeiids (PCA) Jul 22 00:39 (010) +69 42 06:00 <1 – <1 IV
49 Andromedids (FAN) Jul 21 00:41 (010) +43 60 06:00 <1 – <1 IV
phi Piscids (PPS) Jul 05 01:16 (019) +26 67 07:00 2 – 1 IV
c-Andromedids (CAN) Jul 09 01:46 (026) +47 58 08:00 1 – <1 IV
July chi Arietids (JXA) Jul 13 01:58 (030) +07 69 08:00 1 – 1 IV

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Colonial-era slave cemetery studied in Peru

Occasionally, archaeologists provide information about findings related to elites from different periods, but Luis Santa Cruz has proposed something different: to study the way a neglected population —African slaves and Afro-descendants— used to live in the Colonial era. To that end, he chose a location that provided evidence of a cemetery for people of this social group.

Colonial-era slave cemetery studied in Peru
Credit: Andina

A study by Julio Luna Obregon — Ephigenia, the black saint: a brief historical tale on the Afro-descendant saint’s religious practices and Afro-descendant roots in Cañete — stated that, based on documents from La Buena Muerte Convent, slaves had been buried somewhere in La Quebrada estate.
This assertion was confirmed in 2017, and archaeological works started last year, shedding light on the life of slaves in Peru.

Colonial-era slave cemetery studied in Peru
Credit: Andina

Santa Cruz told Andina news agency that the type of soil where these bodies were buried has not been conductive to preservation of much of the material and bones. However, a lot of information can be extracted from skeletal remains.
He says dental modifications —a common practice among African ethnic groups at that time— reveal the continent of origin of the buried persons.

Colonial-era slave cemetery studied in Peru
Credit: Andina

Likewise, he said the conditions of the bones can give more detailed information about their health, for example, their back problems caused by hard work and generalized malnutrition.
Archaeologists found remnants of cloth, so they believe a piece of sheet was placed over their body before being covered with a thin layer of soil during their burial.

Colonial-era slave cemetery studied in Peru
Credit: Andina

The unearthed material is expected to provide evidence of the African region they had come from and, in a couple of years, reconstruct the face of some of them. It must be noted this cemetery was used between 1748 and 1817.

Additionally, locals told archaeologists that some graves were unveiled during the 7.9-magnitude earthquake in 2007.

The remains were relocated within the area and found by the Santa Cruz team in 2018.

Source: Andina [June 29, 2019]



After decades, Japan courts controversy resuming commercial whaling

Japanese fishermen set sail on Monday to hunt whales commercially for the first time in more than three decades after Tokyo’s controversial withdrawal from the International Whaling Commission (IWC) triggered outrage from environmental groups.

After decades, Japan courts controversy resuming commercial whaling
Japan’s decision in December to withdraw from the International Whaling Commission sparked
a firestorm of criticism from environmentalists [Credit: Jiji Press/AFP]

The planned hunts, while small and far from internationally protected waters, have also sparked anger in countries where whaling is considered outdated and harmful.

But in Japan, whaling communities hailed the return of the practice, with Tokyo defending it as a tradition that should not be subject to outside interference.

For years, the issue of whaling was a diplomatic headache for Japan, which came under attack for exploiting an IWC loophole to hunt whales for «scientific» purposes.

Critics accused Japan of effectively carrying out stealth whaling, saying the hunts had no scientific value, while Tokyo continued to push for permission to resume commercial whaling outright.

But last year it announced it would simply withdraw from the IWC and no longer comply with its decades-old ban on commercial killing of the ocean giants.

The decision comes into effect from July 1, when a flotilla of ships that once carried out whaling for «scientific research» will set sail from the Shimonoseki port in western Japan.

Elsewhere, five small whaling boats from across the country will gather in Kushiro port in northern Japan and start hunting minkes for about a week in a symbolic event celebrating the resumption of the practice.

«We are very excited at the resumption of commercial whaling,» Yoshifumi Kai, head of the Japan Small-Type Whaling Association, told AFP ahead of the departure.

«My heart is full of hope,» added Kai, who belongs to a fisheries cooperative in Taiji in Wakayama prefecture, an area known for both whale and dolphin hunting.

Japan’s decision in December to withdraw from the IWC sparked a firestorm of criticism from environmentalists and anti-whaling countries such as Australia, New Zealand and Canada.

After decades, Japan courts controversy resuming commercial whaling
Japan has hunted whales for centuries and the meat was a key source of protein in
 the immediate post-World War II years when the country was desperately poor
[Credit: Kazuhiro Nogi/AFP]

It came after years of failed attempts by Tokyo to convince the IWC to allow it to resume commercial whaling, arguing that stocks of certain species were now sufficient to support renewed hunting.

The decision means Japan will end its most provocative expeditions, in protected Antarctic waters, and instead concentrate on commercial whaling of minke and other whales off its shores.

Japan has hunted whales for centuries and the meat was a key source of protein in the immediate post-World War II years when the country was desperately poor.

But consumption has declined significantly in recent decades, with much of the population saying they rarely or never eat whale meat, and activists have pressed Japan to ditch the practice.

Animal conservation groups from across the world sent a letter to the Group of 20 leaders meeting in the Japanese city of Osaka over the weekend urging them to call for an «immediate end to all commercial whaling.»

«Japan leaving the IWC and defying international law to pursue its commercial whaling ambitions is renegade, retrograde and myopic,» said Kitty Block, president of Humane Society International based in the UK.

Tokyo is «undermining its reputation for an industry whose days are so clearly numbered, to produce a product for which demand has plummeted», she said.

But some conservationists and experts say Japan’s whaling industry is already on its last legs for economic reasons, with consumption shrinking steadily and no sign of a market recovery.

«What we are seeing is the beginning of the end of Japanese whaling,» said Patrick Ramage, director of marine conservation at the International Fund for Animal Welfare.

«Japan is quitting high-seas whaling… not yet a full stop, but that is a huge step towards the end of killing whales for their meat and other products,» he said, adding he does not believe coastal whaling will survive given dwindling subsidies and consumer demand.

Masayuki Komatsu, a former top Japanese negotiator at the IWC between 1991 and 2004, said Tokyo should return to the organisation or risk seeing whaling die out altogether.

Compared to research whaling programmes in the Antarctic and the Northern Pacific, «the size of coastal whaling is tiny,» he told AFP.

«The withdrawal from the IWC means the Japanese whaling industry is on the path towards extinction.»

Author: Kyoko Hasegawa | Source: AFP [June 30, 2019]



Spiralling filaments feed young galaxies

Galaxies grow by accumulating gas from their surroundings and converting it to stars, but the details of this process have remained murky. New observations, made using the Keck Cosmic Web Imager (KCWI) at the W. M. Keck Observatory in Hawaii, now provide the clearest, most direct evidence yet that filaments of cool gas spiral into young galaxies, supplying the fuel for stars.

Spiralling filaments feed young galaxies
Artist’s impression of a growing galaxy shows gas spiraling in toward the center. New observations from the Keck
Cosmic Web Imager provide the best evidence yet that cold gas spirals directly into growing galaxies
via filamentous structures. Much of the gas ends up being converted into stars
[Credit: Adam Makarenko/W. M. Keck Observatory]

«For the first time, we are seeing filaments of gas directly spiral into a galaxy. It’s like a pipeline going straight in,» says Christopher Martin, a professor of physics at Caltech and lead author of a new paper appearing in the journal Nature Astronomy. «This pipeline of gas sustains star formation, explaining how galaxies can make stars on very fast timescales.»

For years, astronomers have debated exactly how gas makes its way to the center of galaxies. Does it heat up dramatically as it collides with the surrounding hot gas? Or does it stream in along thin dense filaments, remaining relatively cold? «Modern theory suggests that the answer is probably a mix of both, but proving the existence of these cold streams of gas had remained a major challenge until now,» says co-author Donal O’Sullivan (MS ’15), a PhD student in Martin’s group who built part of KCWI.

KCWI, designed and built at Caltech, is a state-of-the-art spectral imaging camera. Called an integral-field unit spectrograph, it allows astronomers to take images such that every pixel in the image contains a dispersed spectrum of light. Installed at Keck in early 2017, KCWI is the successor to the Cosmic Web Imager (CWI), an instrument that has operated at Palomar Observatory near San Diego since 2010. KCWI has eight times the spatial resolution and 10 times the sensitivity of CWI.

«The main driver for building KCWI was understanding and characterizing the cosmic web, but the instrument is very flexible, and scientists have used it, among other things, to study the nature of dark matter, to investigate black holes, and to refine our understanding of star formation,» says co-author Mateusz (Matt) Matuszewski (MS ’02, PhD ’12), a senior instrument scientist at Caltech.

The question of how galaxies and stars form out of a network of wispy filaments in space—what is known as the cosmic web—has fascinated Martin since he was a graduate student. To find answers, he led the teams that built both CWI and KCWI. In 2017, Martin and his team used KCWI to acquire data on two active galaxies known as quasars, named UM 287 and CSO 38, but it was not the quasars themselves they wanted to study.

Nearby each of these two quasars is a giant nebula, larger than the Milky Way and visible thanks to the strong illumination of the quasars. By looking at light emitted by hydrogen in the nebulas—specifically an atomic emission line called hydrogen Lyman-alpha—they were able to map the velocity of the gas. From previous observations at Palomar, the team already knew there were signs of rotation in the nebulas, but the Keck data revealed much more.

«When we used Palomar’s CWI previously, we were able to see what looked like a rotating disk of gas, but we couldn’t make out any filaments,» says O’Sullivan. «Now, with the increase in sensitivity and resolution with KCWI, we have more sophisticated models and can see that these objects are being fed by gas flowing in from attached filaments, which is strong evidence that the cosmic web is connected to and fueling this disk.»

Martin and colleagues developed a mathematical model to explain the velocities they were seeing in the gas and tested it on UM287 and CSO38 as well as on a simulated galaxy.

«It took us more than a year to come up with the mathematical model to explain the radial flow of the gas,» says Martin. «Once we did, we were shocked by how well the model works.»

The findings provide the best evidence to date for the cold-flow model of galaxy formation, which basically states that cool gas can flow directly into forming galaxies, where it is converted into stars. Before this model came into popularity, researchers had proposed that galaxies pull in gas and heat it up to extremely high temperatures. From there, the gas was thought to gradually cool, providing a steady but slow supply of fuel for stars. In 1996, research from Caltech’s Charles (Chuck) Steidel, the Lee A. DuBridge Professor of Astronomy and a co-author of the new study, threw this model into question. He and his colleagues showed that distant galaxies produce stars at a very high rate—too fast to be accounted for by the slow settling and cooling of hot gas that was a favored model for young galaxy fueling.

«Through the years, we’ve acquired more and more evidence for the cold-flow model,» says Martin. «We have nicknamed our new version of the model the ‘cold-flow inspiral,’ since we see the spiraling pattern in the gas.»

«These type of measurements are exactly the kind of science we want to do with KCWI,» says John O’Meara, the Keck Observatory chief scientist. «We combine the power of Keck’s telescope size, powerful instrumentation, and an amazing astronomical site to push the boundaries of what’s possible to observe. It’s very exciting to see this result in particular, since directly observing inflows has been something of a missing link in our ability to test models of galaxy formation and evolution. I can’t wait to see what’s coming next.»

Author: Whitney Clavin | Source: California Institute of Technology [July 01, 2019]



Insect apocalypse: German bug watchers sound alarm

For almost 30 years they passed as quirky eccentrics, diligently setting up their insect traps in the Rhine countryside to collect tens of millions of bugs and creepy crawlers.

Insect apocalypse: German bug watchers sound alarm
Insects, which comprise two thirds of all terrestrial species, have been dying off at alarming rates,
with disastrous impacts on food chains and habitats, amateur German researchers have found
[Credit: Ina Fassbender/AFP]

Now the group of German entomology enthusiasts can boast a world-class scientific treasure: evidence of what is described as one of Earth’s worst extinction phases since the dinosaurs vanished. Insects, which comprise two thirds of all terrestrial species, have been dying off at alarming rates, with disastrous impacts on food chains and habitats, researchers say.

The home of the Amateur Entomology Society of Krefeld on the Dutch border is a former school building where thick curtains block out the sunlight. Inside in glass cabinets are stored thousands of butterflies, their wings bleached by time, along with exotic fist-sized beetles and dragonflies, brought back from around the world by amateur collectors.

Traditionally «entomology was mainly about drying and collecting rare specimens,» says the society’s president Martin Sorg, wearing John Lennon-style glasses, a multi-pocket jacket and sandals. He and an army of volunteers have over the years gathered as many as 80 million insects that are now floating in countless ethanol bottles. Each bottle contains the amount caught by a single insect trap over a set period, and each box represents a collection of such catches over nearly three decades.

«Since 1982, the traps we manufacture ourselves have been standardised and controlled, all of the same size and the same material, and they are collected at the same rate in 63 locations that are still identical,» explains Sorg.

The result is a treasure trove of quantitative data that dwarfs that of any funded university project, he says. But if he is visibly proud of the society’s research, the outcome terrifies him: in the test period, the total biomass of flying insects here has plummeted by 76 percent.

To demonstrate the rapid decline, a lab technician holds up two bottles: one from 1994 contains 1,400 grammes of trapped insects, the newest one just 300 grammes. «We only became aware of the seriousness of this decline in 2011, and every year since then we have seen it get worse,» says Sorg, the man who sounded the alarm.

Insect apocalypse: German bug watchers sound alarm
These butterflies are part of a collection of insects at the Entomology Society in Krefeld, western Germany
that its president says is a «treasure trove» of quantitative data
[Credit: Ina Fassbender/AFP]

At the time, the news didn’t make major waves outside ecological circles. Concern about biodiversity loss focused mostly on large charismatic mammal species, and environmental monitoring such as that in Krefeld was considered a quaint Sunday hobby, largely ignored by the scientific community.

Also in 2011, just across the Dutch border, ecology professor Hans de Kroon was working on the decline of birds in the region. He hypothesised that the birds suffered from a shortage of food, especially insects, but had no data to prove it.

«Then our German colleagues from Krefeld got in touch and said, ‘we have the data, we’ve witnessed a strong decline, we are very concerned, could you analyse the data?’. That’s how it all started.»

In the search for the cause, the landscape around Krefeld provides some clues. In the distance, industrial chimneys billow smoke. On one side of the road lies a protected nature reserve. On the other, a sugar beet field is being sprayed with pesticides by an agricultural machine. «You see, protected reserves are not so protected,» says Sorg.

Across the border, Kroon says, «we must realise that here in western Europe our nature is getting smaller, the agriculture fields are very hostile to insects. There is no food, they get poisoned. And nature areas are also more and more isolated. Insects can’t move from one place to another, it’s too far away.»

Although the exact cause for the die-off is not yet clear, he says, «the cause is anthropogenic, there’s no doubt about it. It is our greatest fear that a point of no return will be reached, which will lead to a permanent loss of diversity.»

Insect apocalypse: German bug watchers sound alarm
The contents of an insect trap underscore Kroon’s fears that western Europe could
soon reach «a point of no return» in terms of shrinking biodiversity
[Credit: Ina Fassbender/AFP]

The Krefeld research played a central role in a meta-study published by Francisco Sanchez-Bayo and Kris Wyckhuys from the Australian universities of Sydney and Queensland.
In February, they published the first synthesis of 73 studies on entomological fauna around the world over the past 40 years, listing places from Costa Rica to southern France. They calculated that over 40 percent of insect species are threatened with extinction, and each year about one percent is added to the list. This is equivalent, they noted, to «the most massive extinction episode» since the dinosaurs disappeared.

The main drivers appeared to be habitat loss and land conversion to intensive agriculture and urbanisation, followed by pollution, mainly from pesticides and fertilisers, invasive species and climate change.

«The conclusion is clear,» they wrote. «Unless we change our ways of producing food, insects as a whole will go down the path of extinction in a few decades.»

Author: Daphne Rousseau | Source: AFP [July 01, 2019]




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