вторник, 11 февраля 2020 г.

ALMA catches beautiful outcome of stellar fight


Astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA), in which ESO is a partner, have spotted a peculiar gas cloud that resulted from a confrontation between two stars. One star grew so large it engulfed the other which, in turn, spiralled towards its partner provoking it into shedding its outer layers.

ALMA catches beautiful outcome of stellar fight
ALMA image of HD101584 [Credit: ALMA (ESO/NAOJ/NRAO), Olofsson et al.
Acknowledgement: Robert Cumming]
Like humans, stars change with age and ultimately die. For the Sun and stars like it, this change will take it through a phase where, having burned all the hydrogen in its core, it swells up into a large and bright red-giant star. Eventually, the dying Sun will lose its outer layers, leaving behind its core: a hot and dense star called a white dwarf.


"The star system HD101584 is special in the sense that this 'death process' was terminated prematurely and dramatically as a nearby low-mass companion star was engulfed by the giant," said Hans Olofsson of the Chalmers University of Technology, Sweden, who led a recent study, published in Astronomy & Astrophysics, of this intriguing object.

Thanks to new observations with ALMA, complemented by data from the ESO-operated Atacama Pathfinder EXperiment (APEX), Olofsson and his team now know that what happened in the double-star system HD101584 was akin to a stellar fight. As the main star puffed up into a red giant, it grew large enough to swallow its lower-mass partner. In response, the smaller star spiralled in towards the giant's core but didn't collide with it. Rather, this manoeuvre triggered the larger star into an outburst, leaving its gas layers dramatically scattered and its core exposed.


The team says the complex structure of the gas in the HD101584 nebula is due to the smaller star's spiralling towards the red giant, as well as to the jets of gas that formed in this process. As a deadly blow to the already defeated gas layers, these jets blasted through the previously ejected material, forming the rings of gas and the bright bluish and reddish blobs seen in the nebula.

A silver lining of a stellar fight is that it helps astronomers to better understand the final evolution of stars like the Sun. "Currently, we can describe the death processes common to many Sun-like stars, but we cannot explain why or exactly how they happen. HD101584 gives us important clues to solve this puzzle since it is currently in a short transitional phase between better studied evolutionary stages. With detailed images of the environment of HD101584 we can make the connection between the giant star it was before, and the stellar remnant it will soon become," says co-author Sofia Ramstedt from Uppsala University, Sweden.


Co-author Elizabeth Humphreys from ESO in Chile highlighted that ALMA and APEX, located in the country's Atacama region, were crucial to enabling the team to probe "both the physics and chemistry in action" in the gas cloud. She added: "This stunning image of the circumstellar environment of HD101584 would not have been possible without the exquisite sensitivity and angular resolution provided by ALMA."

While current telescopes allow astronomers to study the gas around the binary, the two stars at the centre of the complex nebula are too close together and too far away to be resolved. ESO's Extremely Large Telescope, under construction in Chile's Atacama Desert, "will provide information on the 'heart' of the object," says Olofsson, allowing astronomers a closer look at the fighting pair.

This research was presented in a paper published in Astronomy & Astrophysics.

Source: ESO [February 05, 2020]



* This article was originally published here

Commander’s House, Housesteads Roman Fort, Hadrian’s Wall, Northumberland, 8.2.20.

Commander’s House, Housesteads Roman Fort, Hadrian’s Wall, Northumberland, 8.2.20.



* This article was originally published here

Triumphal Arch in Anavarza restored


Restoration work has been completed in the gate of the ancient city of Anavarza (Greek Anazarbus), one of the most important settlements in Anatolia on the UNESCO World Heritage Temporary List.

Triumphal Arch in Anavarza restored
Credit: AA
The gate was built in memory of the victory of the Romans against the Persians in the 3rd century and is called the 'Triumphal Arch'. With the recent restoration work, the arch has gained its former glory.


Speaking to state-run Anadolu Agency, Çukurova University archaeology department member and the scientific consultant to the excavations, Fatih Gülşen said that the restoration work in the gate was initiated in 2018.

Triumphal Arch in Anavarza restored
Credit: AA
He said that the ground studies of the gate were carried out in the first stage and, following the reinforcement of the ground, they started the restoration work in the 28-metre-long, 5.40-metre-wide and 14-metre-high gate.


“The ancient city of Anavarza, located in the southern province of Adana, is noted for its theatre, amphitheatre, stadium and 2,700-metre-long and 34-metre-wide colonnade street. The gate called ‘Triumphal Arch,’ built in memory of the victory of the Romans in the ancient city against the Persians in the 3rd century, is one of the most important elements of this place."


"The Triumphal Arch, consisting of three arches, eight legs and six columns and located at the starting point of the world’s first double road, is one of the largest monumental city gates in Anatolia. We restored the stones on the gate, which were in bad condition and posed danger. We replaced the broken stones with the new ones,” he said.

After the Triumphal Arch, excavation and restoration works will start on a 200-metre section of the colonnade street, Gülşen said.

Source: Hurriyet Daily News [February 03, 2020]



* This article was originally published here

West Gate and Bakeries, Housesteads Roman Fort, Hadrian’s Wall, Northumberland, 8.2.20.

West Gate and Bakeries, Housesteads Roman Fort, Hadrian’s Wall, Northumberland, 8.2.20.



* This article was originally published here

Ancient lion statue found at Cambodia’s temple complex


Cambodian archaeologists have unearthed a large ancient lion statue during an excavation at an ancient pond’s jetty in the Banteay Chhmar temple's complex in the northwestern province of Banteay Meanchey.

Ancient lion statue found at Cambodia’s temple complex
Credit: Khmer Culture Ministry


Prak Sovannara, director-general of the culture ministry's heritage department, said the statue was found by accident on February 3 by a group of the ministry's archaeologists while digging the pond's jetty.

Ancient lion statue found at Cambodia’s temple complex
Credit: Khmer Culture Ministry


The statue was made of sandstone and dates back to the late 12th or early 13th century, he said, adding that it was buried more than a metre under the ground and is still in good shape.

Ancient lion statue found at Cambodia’s temple complex
Credit: Khmer Culture Ministry


Located in Banteay Meanchey's Thmar Puok district, the Banteay Chhmar temple was built in the late 12th or early 13th century during the reign of King Jayavarman VII. Its outer gallery is carved with bas-reliefs depicting scenes of military engagements and daily life.

Ancient lion statue found at Cambodia’s temple complex
Credit: Khmer Culture Ministry
The temple is one of the several ancient sites that Cambodia has planned to nominate for the UNESCO-recognised world heritage status.

Source: Vietnam Plus [February 04, 2020]



* This article was originally published here

North Gate, Barracks and Granary, Housesteads Roman Fort, Hadrian’s Wall, Northumberland,...

North Gate, Barracks and Granary, Housesteads Roman Fort, Hadrian’s Wall, Northumberland, 8.2.20.



* This article was originally published here

Russian scientists peek into skull of Earth’s top predator from 250 million years ago


A computer tomography has allowed the scientists to create a 3D reconstruction of the only available skull of a Garjainia - one of the Earth’s most ancient predators, the Moscow Health Department’s Scientific and Practical Clinical Center for Diagnostics and Telemedicine.

Russian scientists peek into skull of Earth’s top predator from 250 million years ago
The fossilised skull of a Garjainia [Credit: Viktor Gombolevsky]
The Garjainia reptile genus that inhabited the Earth approximately 250 million years ago, was an archosaur - the ancestor of the dinosaurs.

Now, scientists have the ability to trace the evolution of the ancient reptile’s brain, the center’s press-service told TASS.

The center carried out the research in conjunction with the Saint Petersburg State University (SPSU) and the Borissiak Paleontologocal Institute of the Russian Academy of Sciences.


"Thanks to the specially developed high resolution scanning protocol, we were able to create a high-definition three-dimensional skull reconstruction, which would allow us to study small anatomical details and trace the evolution of the brain and other intracranial structures in one particular archosaur group," says the center’s statement.

The scientists explained that some 250 million years ago, at the top of the world’s food chain stood Erythrosuchidae, or "red crocodiles," a family of now extinct reptiles, believed to be the ancestors of the dinosaurs and modern crocodiles. The family included several genera, the Garjainia being the earliest of them. Soviet paleontologist Vitaly Ochev identified this genus in 1958, and he named it after Vladimir Garyainov, an archaeologist, who discovered an entire burial ground of reptiles in the Orenburg Region in the 1950s. Unfortunately, the scientists were able to recover only one Garjainia skull intact.

Russian scientists peek into skull of Earth’s top predator from 250 million years ago
Artistic reconstruction of Garjainia [Credit: Mark Witton]
"Erythrosuchidae have never before undergone three-dimensional scanning of the cranial and inner ear cavities. We expect that this would provide new information about its structure, give us some insight into its sense of hearing, balance, head position and maybe even behavior," says Ivan Kuzmin of SPSU’s Faculty of Biology.

"However, our main goal is to reconstruct its lineage, based on the newly discovered anatomical features of the cranial section of the skull, as well as to discuss the relations of different genera and the evolution of the cranial section in this particular archosaur group over 250 million years," he added.


The scientists have created a photorealistic 3D reconstruction, which would make it possible to precisely measure the internal structure, calculate the inner volume, and trace the blood vessels and nerves through the natural bone orifices. This should allow scientists to map out the evolution of blood and nerve canals over time.

The scientists have also managed to scan the reptile’s teeth.

"This would allow us to obtain additional data from the cores of the intact teeth, hidden from external influence under its firm enamel - the most durable part of the reptile’s body. This unique "time capsule" waited 250 million years. Now, using modern spectral computer tomography, we will attempt to compare the [garjainia’s] dentin with teeth of its modern relatives - crocodiles," says Viktor Gombolevsky, who heads the Center’s Radiology Quality Development Department.

Source: TASS News Agency [January 31, 2020]



* This article was originally published here

Model of Housesteads Roman Fort, Hadrian’s Wall, Northumberland, 8.2.20.

Model of Housesteads Roman Fort, Hadrian’s Wall, Northumberland, 8.2.20.



* This article was originally published here

Iran resumes archaeological exploration at ancient Qumis


A new round of archaeological exploration has been commenced at the ancient Shahr-e Qumis in Damghan, north-central Iran, which was once one of the capital of the Parthian Empire (247 BCE – 224 CE).

Iran resumes archaeological exploration at ancient Qumis
Ruins at Šahr-e Qumis or Sahr-i Qumis thought to be Hecatompylos-Qumis, also known as Hecatompylos,
was an ancient city of uncertain location which was the capital of the Arsacid dynasty
by 200 BCE [Credit: Tehran Times]
“This [round of] exploration aims to document archaeological remains of the site by the means of remote sensing and field observations in order to identify the reasons for the formation of the site as a goal of this multi-year project,” ILNA reported.

The project is led by Iranian archaeologist Kourosh Roustaei under the supervision of Iran’s Research Institute of Cultural Heritage and Tourism.


Today, the plain of Shahr-e Qumis is absolutely deserted, but everywhere, one can see the remains of an old city, which was, according to the Greek author Appian of Alexandria, founded by the Seleucid king Seleucus I Nicator.

Shahr-e Qumis comprises several ancient mounds. Only a few of them have been properly excavated, and the area between them has mostly been ignored. The field of shards at Shahr-e Qumis measures some 7 by 4 kilometres or 28 square kilometres, which suggests that it must have boasted tens of thousands of inhabitants.

Some say that Alexander the Great stopped here in Shahr-e Qumis in the summer of 330 BCE and it became part of the Seleucid Empire after his death. Qumis was destroyed by an earthquake in 856 CE, and it was probably abandoned thereafter.

Source: Tehran Times [February 07, 2020]



* This article was originally published here

Roman Bath House, Chesters Roman Fort, Hadrian’s Wall, Northumberland, 8.2.20.

Roman Bath House, Chesters Roman Fort, Hadrian’s Wall, Northumberland, 8.2.20.



* This article was originally published here

Replica Phoenician ship completes Atlantic voyage


The replica Phoenician ship, Phoenicia has arrived in the U.S. after a five-month voyage of over 6,000 miles. The voyage is part of the Phoenicians Before Columbus Expedition, designed with the help of the US-based Phoenician International Research Center, to show that Phoenician ships could have crossed the Atlantic over 2,000 years before Christopher Columbus “discovered” the American continent.

Replica Phoenician ship completes Atlantic voyage
Replica Phoenician Ship, the Phoenicia made landfall in Fort Lauderdale, Florida
after an unprecedented 6,000-mile Atlantic voyage [Credit: Associated Press]
The Phoenicia began its voyage from Carthage, Tunisia on September 28, 2019. After sailing from Carthage to Cadiz, Spain, Essaouira, Morocco and Tenerife in the Canary Islands, the ship left the Old World on November 23, 2019 and safely reached port in the Dominican Republic on December 31, 2019, having crossed the Atlantic Ocean using nothing but wind, current, sail and compass.

The Phoenicia made landfall on American shores on Tuesday, February 4, 2020, docking at Coral Ridge Yacht Club in Fort Lauderdale, Florida.


The Phoenicia is a traditionally-built replica of a Phoenician merchant vessel, based on a 600 BC design. British Adventurer and Expedition Leader, Philip Beale FRGS, captains the Phoenicia, sailing with a multi-national crew with representatives from the United States, Lebanon, Tunisia, United Kingdom, Norway, Holland, Brazil and Indonesia. Amongst the crew is filmmaker Yuri Sanada from Aventuras Produções, Brazil. He is documenting life on board as well as the challenges the Phoenicians were likely to have faced.

According to Greek geographer and historian, Strabo, the Phoenicians traded and settled along the East Atlantic coast, prompting Beale’s belief in the likelihood that the Phoenicians would have attempted to sail West in the hope of discovering more lands. Beale commissioned the building of the Phoenicia ship 12 years ago. It was traditionally built in Syria and its design was based on the wreckage of the Jules Vernes 7, discovered in the Mediterranean in the early 1990’s. The Phoenicia is believed to be the only replica of its kind in the world. Having already circumnavigated Africa in the First Phoenician Ship expedition (2008-10), Beale was once again at the helm for the cross Atlantic challenge; reiterating his passion for the seafaring Phoenicians.


The Expedition has been endorsed by the Ministries of Information and Tourism of the Republic of Lebanon and received support, expedition supplies and services from numerous organizations in the Republic of Tunisia, prior to the launch of the Expedition from Carthage, Tunisia in September 2019. The Expedition is part of the United Nations Environment ‘Clean Seas Campaign’, taking daily water samples to measure micro plastic levels and raising awareness about plastic pollution in the ocean.

The journey across the Atlantic from Tenerife to the Dominican Republic took 39 days, a distance of some 3,700 miles. From the Dominican Republic to Florida, the journey of 1,000 miles will take 12 days. The total voyage from Carthage, Tunisia to Florida has covered over 6,000 miles, taking five months to complete.

Source: GlobeNewsWire [February 07, 2020]



* This article was originally published here

ISS Over Puerto Rico

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Channel: Frankie Lucena  

This sighting was on February 10, 2020 at about 7:15 pm local time. I recorded it while flying near Orion,Sirius and Canis Major. The video is sped up to one and a half times to reduce the file size.

Video length: 0:57
Category: Science & Technology
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Interval Tower, Chesters Roman Fort, Hadrian’s Wall, Northumberland, 8.2.20.

Interval Tower, Chesters Roman Fort, Hadrian’s Wall, Northumberland, 8.2.20.



* This article was originally published here

1,200 year-old glass boardgame piece found on Lindisfarne


A rare, glass gaming piece has been discovered during an archaeological dig on Lindisfarne – the tiny Northumbrian island whose wealthy early medieval monastery was infamously raided by Vikings in AD 793, heralding the start of the Viking Age in Britain.

1,200 year-old glass boardgame piece found on Lindisfarne
Blue glass gaming piece discovered at Lindisfarne, ca. 800 AD 
[Credit: DigVentures and Durham University]
The gaming piece was discovered in September 2019 during a community-based archaeological dig led by DigVentures and Durham University, which has uncovered part of the iconic monastery.

Made of bright blue glass with exuberant white swirls, the gaming piece is crowned with a ring of five white bobbles, which mean it is likely to have been a kingpiece.


Dating back to AD 700-900, archaeologists believe it came from a set that would have been used for playing a uniquely Northern British version of ‘tafl’, a family of games which were derived from the Roman war game Ludus Latrunculorum, and played in Britain, Denmark, Iceland, Ireland, Norway and Sweden before the arrival of chess in the 11th-12th centuries.

Other tafl pieces made of wood or bone have been found in elite burials from Anglo-Saxon England, but only one other glass tafl piece has been found in the British Isles, at the Pictish hillfort at Dundurn in present-day Scotland, making this Lindisfarne piece only the second to have been discovered.

1,200 year-old glass boardgame piece found on Lindisfarne
Gaming piece from above [Credit: DigVentures and Durham University]
The next closest examples were found near Dublin, Ireland, in Dorestad, Netherlands, and from a 12th century burial at Birka, Sweden.

“Many people will be familiar with Viking versions of the game, and I’m sure plenty of people will wonder whether this gaming piece was dropped by a Viking during the attack on Lindisfarne, but we believe it actually belonged to a version of the game that was played by the elites of Northern Britain before the Vikings ever set foot here,” said Lisa Westcott Wilkins, Managing Director of DigVentures.

“The Romans were very fond of giving gaming pieces as gifts to ‘barbarian’ princes, and as the game spread out of the Roman empire, different societies developed their own variations on the rules, including Northern Britain.

“In fact, we believe the piece had probably originally been buried with a member of the Northumbrian elite, whose grave was later disturbed,”


“It’s amazing to think that when the Vikings did land here they could, in theory, have sat down with the monks of Lindisfarne to play a game that would have been familiar to both cultures, although they would almost certainly have argued over whose rules to play by!” continued Westcott Wilkins.

Although there were many different versions, the games all follow roughly the same principle of defending a central king against attackers.


“It is extraordinary to find a glass tafl gaming piece like this in such perfect condition. They’re as rare as hen’s teeth,” said Mark Hall, a leading specialist in Roman and early medieval games, and Collections Officer at Perth Museum & Art Gallery, who inspected the piece when it was found.

Now in its fourth season, the dig has revealed part of a cemetery and a workshop associated with the monastery, both dating to AD 700 – 1000 when activity on the island was at its peak.

1,200 year-old glass boardgame piece found on Lindisfarne
Artefacts from Lindisfarne dig [Credit: DigVentures and Durham University]
“This is a truly wonderful discovery, which gives us a very special insight into life in the monastery at the time” said Dr David Petts, Senior Lecturer in the Archaeology of Northern Britain at Durham University, who co-directs the excavation with DigVentures.

“It’s similar to a number of other examples found at settlements and trading sites around the edge of the North Sea, and shows us not only that there were people on Lindisfarne who had leisure time, but that they were well-connected” said Petts.

“Lindisfarne would have been a busy place back then. Thousands of people would have come on pilgrimage seeking miracles and cures, but the monastery also had strong royal connections: it sits directly opposite Bamburgh Castle, which was the seat of Northumbrian power. This meant it was also a place of refuge for kings, and was regularly visited by elites, nobles, and high-ranking clergy.

“We know that at least one king retired to the island to end his life as a monk, but before he joined the community he changed the rules to ensure that the monks were allowed to drink wine,”

1,200 year-old glass boardgame piece found on Lindisfarne
Lindisfarne 2019 excavation [Credit: DigVentures and Durham University]
“Although people tend to think of Lindisfarne today as a rather remote place, back then it was far from isolated. It was a nexus of cultural connections, with strong links to other parts of Britain, mainland Europe, and even further afield” said Petts.

This year’s investigation also uncovered two copper finger rings, a copper pin, small bronze buckle, and evidence that the workshop may have been related to metal-working, for which the monastery was famous.


Other discoveries include a set of rare early medieval carvings known as ‘namestones’, each of which commemorates someone who was buried on the island during this period. A number of Anglo-Saxon coins were also found, including a coin minted for Aethelred I, king of Wessex from AD 865 – 871.

The excavation, which is led by DigVentures and Durham University, has been entirely crowdfunded by members of the public who are able to watch the discoveries online, or take part in the dig.


“Our team of professional archaeologists works alongside members of the public who want to make a real contribution to archaeological research. We provide all the training and supervision that individuals need in order to dig with our team or work with artefacts in our Finds Room, and experience what it’s like to make an archaeological discovery while learning in-depth how the process of archaeology actually works. It’s really thanks to them that this discovery has been made in the first place,” said Westcott Wilkins.

“In fact, any headline should probably read ‘Archaeologist’s mum finds 1,200 year old gaming piece’, because it was actually found by our Head of Fieldwork’s mother, Heather Casswell, who was taking part in the dig while visiting her son on her birthday!”.

The combined team from DigVentures and Durham University will return to Lindisfarne in September 2020 to continue investigating the site. Anyone who is interested in taking part can find out more about joining the team at https://digventures.com/projects/lindisfarne

Source: DigVentures [February 07, 2020]



* This article was originally published here

Roman Military Hospital, Housesteads Roman Fort, Hadrian’s Wall, Northumberland, 8.2.20.

Roman Military Hospital, Housesteads Roman Fort, Hadrian’s Wall, Northumberland, 8.2.20.



* This article was originally published here

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