Earth’s Collision With Another Planet Probably Started Life

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Earth’s Collision With Another Planet Probably Started Life

Image by A. Passwaters/Rice University/NASA/JPL-Caltech

Researchers from Rice University say that around 4.4 billion years ago, a Mercury-like planet smashed into Earth, seeding our primordial planet with life-giving carbon. Had this never occurred, it’s an open question as to whether or not life could have ever emerged.

Geoscientists have struggled to explain how life was able to arise on Earth given that most of the planet’s carbon—an important prerequisite for life—should have either boiled away during the planet’s earliest stages or become trapped within the Earth’s core. By conducting high-pressure and high-temperature experiments in the lab, researchers from Rice University have concluded that virtually all of our planet’s carbon likely arrived when a Mercury-like planet smashed into the young Earth some 4.4 billion years ago.

Scientists aren’t entirely sure how Earth’s volatile elements, such as carbon, hydrogen, nitrogen, and sulfur, were able to remain outside the Earth’s core and stay locked within the mantle. Models show that most of our planet’s carbon should have vaporized into space, or ended up in the metallic core of our planet, sucked up by its iron-rich alloys.

Prior to the new study, many scientists speculated that these volatile elements came to Earth after our planet’s core finished forming. As Rice University geoscientist and study co-author Yuan Li pointed out in a statement, “Any of those elements that fell to Earth in meteorites and comets more than about 100 million years after the solar system formed could have avoided the intense heat of the magma ocean that covered Earth up to that point.” Trouble is, there are no known meteorites capable of producing the required ratio of volatile elements.

Three years ago, Li and his colleagues began to take a different approach to the problem. They conducted a series of experiments to assess how carbon’s affinity for iron may have been altered by other compounds present in the Earth’s early environment. Importantly, they considered the potential role of other celestial bodies with characteristically different chemical compositions.

“We thought we definitely needed to break away from the conventional core composition of just iron and nickel and carbon,” noted study co-author Rajdeep Dasgupta. “So we began exploring very sulfur-rich and silicon-rich alloys, in part because the core of Mars is thought to be sulfur-rich and the core of Mercury is thought to be relatively silicon-rich.”

The proposed collision was so intense that Earth essentially absorbed the incoming proto-planet. (Image: Rajdeep Dasgupta)

Their experiments recreated the high-pressure and high-temperature conditions found deep inside the Earth and other rocky planets. Results showed that carbon could be excluded from the core and relegated to the Earth’s mantle, provided that the iron alloys in the core were rich in either silicon or sulfur. One scenario that explains this particular ratio is that an embryonic planet—one that already formed a silicon-rich core—slammed into Earth, and was absorbed by Earth.

“Because it’s a massive body, the dynamics could work in a way that the core of that planet would go directly to the core of our planet, and the carbon-rich mantle would mix with Earth’s mantle,” said Gupta.

The researchers say this collision likely happened about 4.4 billion years ago, which is only about 150 to 200 million years after the Earth formed. With carbon locked within the crust, and with the planet settling down to produce habitable conditions, life soon emerged. Indeed, the most recent estimates suggest that microbial life formed approximately 4.1 billion years ago.

It’s important to point out that evidence for this primordial collision is circumstantial as best. The researchers agree that more work is needed to support this theory, including analyses of abundant elements other than carbon. If true, however, it could mean that Earth only became a habitable oasis only after this tremendous cosmic smashup. Carbon forms a key component of all known life on Earth; complex molecules are comprised of carbon bonded with other elements, such as oxygen, hydrogen, and nitrogen.

Regardless, the theory makes you wonder about life on other planets, and how specific the conditions need to be for life to finally emerge on dead, rocky worlds.

[Nature Geoscience]

George is a contributing editor at Gizmodo and io9.

How Scientists Found the Tiny Philae Lander On a Giant Comet

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How Scientists Found the Tiny Philae Lander On a Giant Comet

Today 8:00am
Rosetta’s lander Philae was identified in the shadow of a cliff on September 2nd, at a distance of just 2.7 kilometers. Image: ESA/Rosetta/MPS for OSIRIS Team

In the shadow of a cliff on an icy rock 700 million kilometers from Earth, a washing machine-sized robot by the name of Philae has spent the last two years in hibernation. We’d already given up hope of speaking with humanity’s first and only comet lander ever again, and time was running out to catch a final, fleeting glimpse of the beloved craft. In the eleventh hour, science prevailed.

On Sunday, during its second-to-last pass over Philae’s likely resting spot on Comet 67P/Churyumov-Gerasimenko, the Rosetta spacecraft’s OSIRIS camera obtained visual confirmation of the robotic lander, wedged into a dark crevice beneath a craggy cliff. The fuzzy, oversaturated photo released Monday by the European Space Agency (ESA) is the triumphant culmination of a two-year search, which intensified this past summer as Rosetta spiraled toward Comet 67P in preparation for a controlled descent on September 30th.

“It was a huge adrenaline rush to see this image on Sunday night,” Laurence O’Rourke, the Rosetta mission scientist who coordinated the ESA’s search for Philae, told Gizmodo. “To have searched for this object on the surface for so long, and finally gotten an image of this quality and detail, was such a reward.”

The search for Philae began almost immediately after the lander’sunexpectedly eventful touchdown on November 12th, 2014. The craft bounced several kilometers over the course of two hours before coming to rest in a rocky region. From photos taken by Philae in the vanishing hours before its batteries drained on November 15th, we knew that the lander had tumbled into the shadow of a cliff dubbed Perihelion. What wasn’t clear was whether Philae remained in its original spot beneath the cliff’s shadow, or if it had been blown elsewhere by a cometary outburst. Either way, finding the lander was going to be difficult, given that its most likely resting location received at most a few hours of sunlight per day.

Phiael’s view of its final resting site underneath “Perihelion cliff.” Image: ESA/Rosetta/Philae/CIVA

Nonetheless, a search commenced, with scientists pulling together troves of data—radio signals sent from Rosetta to Philae and back, images of the surface taken by the orbiter, and images taken by Philae itself—to hone in on the lander’s likely location. A promising elliptical area, named Abydos after the sacred city of ancient Egypt, was soon identified, but actually spotting a lander in Rosetta’s early flyby photos (taken 20 kilometers or more above the surface) proved nearly impossible.

Another important clue came last summer, when Philae briefly woke up and beamed a signal back to Earth. As O’Rourke explained, the lander had stored data on the position of the sun from the months prior to its phone call home. “You could take that data, plot it on the sky and say, this is where Philae would be if the sun were in that position,” he said. “This very much helped with the search.”

Eventually, O’Rourke’s team was able to narrow Abydos down to a region just a few tens of meters in diameter. But it wasn’t until earlier this spring that Rosetta got close enough to acquire the hi-res images needed to clearly make out a meter-sized robot on the comet’s surface.

“Distance was the key,” O’Rourke said. “We needed to be below 10 kilometers in order to start picking Philae out from the rocks,” particularly the ice-rich ones whose gleaming surfaces have similar optical properties to Philae’s solar panels.

Comet 67P, with the Abydos region circled in red, as seen by Rosetta on December 13th, 2014 from a distance of 20 km. From this distance, Philae would only be about 3 pixels across. Image: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

Throughout the spring and summer, Rosetta made a series of low-altitude swoops over Abydos, photographing the rugged terrain from different altitudes and illuminations during the course of its normal scientific operations. (Only once, after Philae buzzed the Earth in July 2015, was the spacecraft’s course deliberately altered to aid in the search for the missing lander.) All the while, the illumination grew dimmer as the sun migrated north of the comet, akin to the situation on Earth where winter days are shorter due to the sun being lower in the sky.

In spite of the dying light, evidence was converging on a specific spot beneath the originally suspected site of Perihelion cliff. In addition to capturing several promising images between May and August, the team used 3D surface modeling and automated image searching to hone in on the lander’s precise whereabouts. They also succeeded, on several occasions, in matching Philae’s lost RF signal to the line of sight Rosetta was searching along.

But the ironclad proof came in the form of the image captured on September 2nd, from a distance of just 2.7 kilometers when Philae was in Perihelion cliff’s shadow. Despite the poor illumination, image processing revealed several of Philae’s prominent features, including its meter-wide body and two of its three legs, extended. Several of the lander’s instruments were also identified.

“This was really like solving a mystery,” O’Rourke said. “Gradually, we got more and more clues. We had quite a convincing argument to say this was Philae’s resting site before the [final] picture, but a picture tells a thousand words.

The Philae lander, rest in peace. Image: ESA/Rosetta/MPS for OSIRIS Team

The discovery does more than offer the search team some well-deserved catharsis. “Besides the satisfaction and public impact of now having found [Philae] and knowing where it is, this breakthrough brings new data to the scientific aspects of the Philae mission,” ESA Rosetta mission manager Patrick Martin told Gizmodo.

During its 57 hours of activity on the surface, Philae collected troves of data onComet 67P’s complex surface, in addition to giving us an unprecedented snapshot of the volatile gases and organic molecules present on such a body. Knowledge of Philae’s exact location at the time these measurements were made allows scientists to ground-truth these discoveries.

Finally, Philae’s tumultuous landing, and the quest to rediscover it afterwards, has given scientists and engineers plenty of lessons to ponder when designing future missions. O’Rourke, for his part, has one modest request: that all future comet landers be equipped with emergency LEDs.

Maddie is a staff writer at Gizmodo

10 Recent Discoveries That Shed New Light On Ancient Civilizations

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10 Recent Discoveries That Shed New Light On Ancient Civilizations


Numerous ancient civilizations around the world were advanced and highly civilized. Some are very popular and well-studied like the Egyptians while others remain obscure like the Garamantes. As scholars make new discoveries, our understanding of ancient civilizations will deepen—dispelling myths, correcting inaccurate information, and eliciting more respect and admiration.

10Earthquake Caused The Disappearance Of The Sanxingdui Civilization


Photo credit: momo

Sanxingdui is an ancient Chinese civilization and settlement that flourished in the Sichuan Province of China. For thousands of years, this advanced culture was lost. It was only rediscovered in 1929 when a peasant found jade and stone artifacts while repairing a sewage ditch.

The two prevailing theories about Sanxingdui’s mysterious disappearance are war and flood. However, Niannian Fan from Tsinghua University in Chengdu, China, found these theories to be “not very convincing.” In 2014, he published research that details how an earthquake caused the Sanxingdui civilization to disappear.

According to Fan’s study, a massive earthquake almost 3,000 years ago “caused catastrophic landslides [that] rerouted the flow of [Sanxingdui’s] river.” The inhabitants simply moved closer to the new river flow. This theory is supported by historical records of earthquakes that occurred near Sanxingdui. Fan believes that the inhabitants relocated to Jinsha after the river was rerouted.


9War Was Important For The Minoans


Photo via Wikimedia

Contrary to popular belief, the Minoans, who prospered on Crete during the Bronze Age, were not a peace-loving people. Ever since they were rediscovered over a century ago, the Minoans were regarded as “a paradigm of a society that was devoid of war, where warriors and violence were shunned.”

However, new research conducted by archaeologist Barry Molloy of the University of Sheffield revealed that war played an important role in the Minoan society. Molloy arrived at this conclusion after discovering numerous pieces of evidence depicting violence in the material remains and symbolic grammar of ancient Crete.

In addition, Molloy’s research showed that one of the primary expressions of Minoan male identity was warrior identity. Also, many weapons that dominated Europe until the Middle Ages, such as spears and swords, may have originated from the Minoan civilization.

8The Minoans Were Indigenous Europeans


Photo credit:

For many years, the origin of the ancient Minoan civilization was fiercely debated by scholars. Some suggested that they originated from Africa, specifically Egypt and Libya. Others believed that they came from the Middle East and Anatolia. In 2013, this debate was finally put to rest when Professor George Stamatoyannopoulos from the University of Washington published a study that revealed that the ancient Minoans were indigenous Europeans.

Stamatoyannopoulos analyzed the mitochondrial DNA of 37 ancient Minoans whose remains were discovered in a cave on the eastern portion of Crete. His analyses revealed that the Minoan civilization was genetically distant from the peoples of North Africa and the Middle East. More importantly, the results showed that “ancient Minoan DNA was most similar to populations from western and northern Europe.”


7War Didn’t Cause The Collapse Of The Easter Island Civilization


Photo credit: HeritageDaily

One of the most enduring mysteries of the ancient civilization that flourished in Rapa Nui, Chile, beginning in the 13th century is the cause of its collapse. The theory that many scientists believe and propagate involves massive infighting among the inhabitants caused by dwindling resources. This theory is supported by the thousands of triangular objects known as mata’a that are found all over the island. Scientists believe that these objects were used as weapons by the inhabitants.

However, a new analysis of the mata’a by anthropologist Carl Lipo of Binghamton University and his team revealed that these so-called triangular weapons were not “used in warfare after all.”

They arrived at this controversial conclusion after using a technique known as morphometrics to analyze “the shape variability of a photo set of [more than 400] mata’a.” According to Lipo, the mata’a were used by the inhabitants not as weapons but as cultivation tools for domestic activities or tattooing.

6Climate Change Caused The Collapse Of The Harappan Civilization


Photo credit: M.Imran

Of all the first great urban civilizations in the world, the Harappan civilization is the least known. This is quite surprising considering the fact that this obscure society was bigger, more populous, more democratic, and more sophisticated than ancient Egypt and Mesopotamia. At its peak, the Harappan civilization extended over 1 million square kilometers (390,000 mi2), encompassing lands that now belong to India, Bangladesh, Nepal, and Pakistan.

About 4,000 years ago, this great civilization mysteriously collapsed. The cause remained a mystery until recently.

Liviu Giosan, a geologist from Woods Hole Oceanographic Institution in Massachusetts, and his team recreated the landscape of the rivers and plains where the Harappan civilization flourished. They discovered that ancient climate change caused the monsoon-based rivers supporting the agriculture of the Harappan civilization to dry up. As a result, big cities collapsed and the inhabitants migrated to the East, specifically “toward the Ganges basin, where monsoon rains remained reliable.”

5Elite Women Made The Beer In The Wari Civilization


Photo credit: Chicago Tribune

The Wari, an ancient civilization that predated the Incas, flourished for hundreds of years in the Andes Mountains of Peru before their society collapsed. In 2005, a study conducted by researchers from the University of Florida and the Field Museum revealed that the beer makers of the Wari Empire were women.

More strikingly, the researchers found that the female brewers were neither slaves nor women of low status. Instead, they were elite, beautiful women. This finding proves “that women played a more crucial role in ancient Andean societies than history books have stated.”

The beer prepared by the elite female brewers 1,000 years ago was called chicha. It was made from Peruvian peppertree berries and corn.


4The Garamantes Were Highly Civilized


Photo credit:

The Garamantes are an ancient civilization that flourished in what is now modern-day Libya. Most of what scholars know about this mysterious society comes from Roman accounts, which described them as “barbaric nomads and troublemakers on the edge of the Roman Empire.” However, a new discovery reveals that the Garamantes civilization was actually advanced and historically more important than previously thought.

In 2011, a team of researchers led by archaeologist David Mattingly from the University of Leicester discovered more than 100 fortified farms, towns, and villages with castlelike structures in Libya that date from AD 1 to AD 500.

Contrary to what the Romans had suggested, these structures and settlements prove that the Garamantes were highly civilized. They opened up the trans-Saharan trade and were pioneers of building oases. The researchers made this remarkable discovery after examining air photographs and satellite images.

3The Nazca Civilization Caused Its Own Demise


Photo credit: Liliana Usvat

The Nazca is perhaps one of the most mysterious civilizations in the history of mankind. Around 1,500 years ago, this advanced society in Peru mysteriously collapsed. Scientists have suggested a massive El Nino event as the culprit. However, new research shows that massive deforestation also played a key role in the demise of the Nazca civilization.

Archaeologist David Beresford-Jones of Cambridge University discovered that the ancient Nazca cut down native huarango trees to plant maize, cotton, and other crops. The huarango trees played important roles in the desert environment of the Nazca. These trees enhanced moisture and soil fertility, provided shade from the scorching heat of the desert, and underpinned the floodplain.

The cutting down of the huarango trees caused irreversible damage to the environment. When the massive El Nino occurred, the huarango trees were no longer there to prevent or reduce flooding. As a result, the floods damaged the irrigation systems, leaving the Nazca with an area unworkable for agriculture.

2Child Sacrifice Was Practiced By The Carthaginians


Photo credit: The Guardian

For decades, scholars have debated whether the people of ancient Carthage, who existed from 800 BC to 146 BC, practiced child sacrifice. The notion that the ancient Carthaginians did not engage in this cruel practice was propagated by scholars from Italy and Tunisia during the 20th century.

They argued that the Greeks and Romans were behind this “racist anti-Carthaginian propaganda.” They also suggested that the tophets—ancient burial grounds where the skeletons were found—were simply child cemeteries.

However, collaborative research carried out by academics from various institutions around the world, such as Oxford University, slams this misguided interpretation. According to the study, the overwhelming amount of archaeological, literary, documentary, historical, and epigraphic evidence points to the fact that Carthaginian parents did sacrifice their own children to the gods.

1Dwarfs Were Highly Respected In Ancient Egypt


Photo credit: Steve F-E-Cameron

In 2005, a study published in the American Journal of Medical Geneticsshowed that the ancient Egyptians held dwarfs in high esteem, possibly as far back as 4500 BC. These researchers from Georgetown University Hospital arrived at this conclusion after examining artistic evidence and biological remains of dwarfism in ancient Egypt.

They discovered an overwhelming number of dwarf images on vase paintings, statues, tomb walls, and other art forms. The images portrayed dwarfs as “personal attendants, overseers of linen, people who looked after animals, jewelers, dancers, and entertainers.”

In addition, the researchers found that several dwarfs held important positions and were revered enough to be buried in lavish burial sites in the royal cemetery. The study concluded that dwarfism “was never shown as a physical handicap” in ancient Egypt.

10 Curious Coins And Coin Tokens From History

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10 Curious Coins And Coin Tokens From History


In the past, the use of coins was much more varied. They were used for commerce, of course, but also for purposes of social exclusion or for healing. They could even be used to express love.



Photo credit: Matthias Kabel

Spintriae were erotic Roman coins minted from bronze or brass in the early first century. One side depicted a sexual act, while the other side depicted a Roman numeral from I to XVI.

The most common theory suggests they were used for admission into brothels. The picture side depicted the pleasures on offer, and the number side stated the chamber where these pleasures were to be provided. Alternatively, the numeral could have depicted the price of the sexual act, eliminating language barriers. Spintriae were used instead of ordinary coins to circumvent the law that bringing currency bearing the emperor’s image into a brothel was treason.

However, some claim that it is unlikely that spintriae were used as brothel tokens for numerous reasons, such as their appearance in bathhouses but never in the ruins of actual brothels. Perhaps they were tokens in a game whose rules are unknown to us.


9Angel Coin


From the Middle Ages to the early 18th century, it was believed that scrofula (a disease of the lymph nodes) could be treated, and sometimes even cured, by a monarch touching the infection. Of course, monarchs did not actually want to touch victims of the disease. Thus was born the alternative practice of a monarch touching a gold coin that could be later pressed to the infected area.

Coins became known as “touch pieces.” Gold coins known as an “angel” were the most typical choice. The reverse side of an angel coin depicted the archangel Michael standing over a defeated Satan, symbolizing the triumph of good over evil.

In 1714, George I, who regarded touch pieces as a Catholic superstition, abolished the ceremony.

8Leaden Hearts


Photo credit:

Leaden Hearts were love tokens crafted by British convicts moved to Australia and Tasmania during the late 18th and the early 19th century. Most sentences were to last 7–14 years, so convicts wanted to leave some sort of forget-me-not to their loved ones.

Leaden hearts were made by smoothing a coin on one or both sides. The coin was then engraved with a message of affection meant for the convict’s loved ones. The engraving work was done with a series of small pin pricks and often included the names of the convict and their loved one, the length of separation, as well as phrases and rhymes of separation.


7Hobo Nickels


Photo credit: Carptrash/Wikimedia

Coins have always been favored as an artistic medium. In 1913, for example, the Buffalo nickel became extremely popular among coin carvers. It provided a larger and thicker canvas to work on than before, so more detailed pieces could be created. Buffalo nickels were also cheaper to work on than quarters.

Carving and selling Buffalo nickels became a common occupation within the transient community and was an especially useful means of extra incomeduring the Great Depression. The carved Buffalo Nickels became known as hobo nickels due to the widespread belief that hobos started carving them on long train rides.

6Hard Times Tokens


Photo credit: Centpacrr/Wikimedia

Hard-times tokens were minted privately from 1832–1844 as unofficial currency, meant to alleviate the shortage of coinage during the American economic depression of 1837–1844.

They were divided into three main categories. The first consisted of political propaganda, mostly for and against Andrew Jackson and his vice president, Martin van Buren. For example, one quoted van Buren’s inaugural speech as “I follow in the footsteps of my illustrious predecessor” and portrayed arunning jackass (representing Jackson) leaving hoof prints behind.

The second category of hard-times tokens consisted of store tokens featuring advertisements. The third were cent look-alikes. Practically all were similar in size and composition to the large cents that they were meant to replace.

5Church Penny


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During the 18th and 19th centuries, some churches in the northeastern United States commissioned special coin tokens to be used in churches only. These were issued to stop counterfeit copper coins, as well as extremely worn coins, from getting into the collection plates. Once the church had bought these tokens, it would sell them on to parishioners, who could then donate them without the fear of upsetting the church.

The First Presbyterian Church of Albany, for example, issued 1,000 such tokens in early 1790. Each was engraved with a circle of scallops and the motto “Church Penny.” The reverse side of the coin was blank.


4French Trezains


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Trezains were 13 coins carved specifically for marriage in France from around the 16th century and possibly earlier. Even though carved with symbols of love such as double flaming hearts and handshakes, they were considered legitimate currency by merchants.

The groom gave the bride trezains as symbolic compensation for the goods or the land she brought to the union. During the wedding, the trezains were blessed by a Catholic priest. The total number of the coins represented Jesus and His twelve apostles. Between one to three coins were given to the priest, while the others were meant to be kept as a keepsake by the newlywed couple. However, they were almost always spent in times of hardship.

3Holey Dollar


Almost immediately after the colony of New South Wales was founded in 1788, it ran into coinage difficulties. Foreign coins were common, but the majority left the colony through trade. Lachlan Macquarie, the governor of the new colony, soon came up with a creative solution.

In 1812, Macquarie imported 40,000 Spanish reales and had the convicted forger William Henshall cut out the center of each. The result both doubled the number of coins available and prevented their export.

The coins were counterstamped and brought into circulation in 1814. Eventually, the outer ring came to be known as the holey dollar and the center as the dump. In 1822, they were replaced with sterling coinage.

2Saudi Arabian Bullion Coins


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Saudi Arabian bullion coins were minted in Philadelphia by the United States Mint in 1945 and 1947. At the time, the Arabian American Oil Company (Aramco) was set up in Saudi Arabia by four American oil companies. Each year, Aramco had to pay $3 million in royalties to the Saudi government. The contract specified that the payment had to be made in gold. At the time, the dollar was governed by a gold standard, and for some time, the Saudis accepted payment in United States currency. However, by 1945, they insisted for payments in gold.

Aramco, faced with the prospect of either a cut-off of much of Middle Eastern oil or the increase in the price of oil, turned to the United States government for help. As a solution, the American government minted 91,210 large gold discs bearing the Great Seal’s eagle. The Saudi Arabian bullion coins thus looked like coins, and they were used as coins, yet they weren’t technically coins.

The coins were shipped off to Saudi Arabia, and most were later melted down into bullion.

1Leper Colony Coins


Photo credit:

Back in the day, leprosy was believed to be contagious and was one of the most feared diseases in the world. Victims were often forced to leave their homes and spend the rest of their lives in colonies known as Lazaretos.

These isolated sanatoriums surrounded hospitals for contagious diseases. But people still feared that leprosy could be transmitted through money, so special currency was developed specifically for leper colonies.

Leper colony coins started in early 20th-century Columbia and then spread to other countries and regions such as the Philippines, Japan, and Panama. At some point, these special leper coins also existed in Brazil, China, Costa Rica, Korea, Nigeria, Thailand, and Venezuela.

IS loss of border area with Turkey sharply harms group

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BASSEM MROUE,Associated Press 20 hours ago