How Life Could Survive on the Newly Discovered Exoplanet Proxima B

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How Life Could Survive on the Newly Discovered Exoplanet Proxima B

Concept of a planet glowing in response to a solar flare from an M dwarf star. Image: Jack O’Malley James

After a week of rampant speculation, astronomers have officially announced the discovery of Proxima b, a potentially habitable world circling our nearest neighboring star. But even as engineers prepare for an interstellar voyage to scope out Proxima b for signs of life, some experts warn that M dwarf systems like Proxima Centauri may be unable to support life at all.

For all those wondering what exactly we’ll discover on the surface of Proxima b—a barren wasteland, or a vibrant, alien biosphere?—a new scientific paperoffers optimism. According to astrobiologists at Cornell University, life could in theory evolve to survive in the high-radiation environment of an active M dwarf, by converting the star’s most damaging rays into harmless visible light. We know this is possible, because the mechanism—called biofluorescence—has evolved numerous times already, right here on Earth.

“The key question that will come out of [the Proxima b] discovery is how you could ever envision life on that planet,” study co-author Lisa Kaltenegger told Gizmodo. “I think it’s fair to use Earth as an inspiration.”

Before we get ahead of ourselves, a little background on M dwarfs. Smaller, cooler and dimmer than the sun, M dwarfs are the most abundant stars in the galaxy. They’re extremely long lived—Proxima Centauri already has 250 million years on our sun, and astronomers estimate it’ll outshine us by a fewtrillion more. Best of all, according to recent exoplanet surveys, M dwarfsappear to be hotbeds for small, rocky exoplanets in the habitable zone where liquid water can form. All of these factors make the galaxy’s dimmest bulbs exciting places to consider in the search for alien life.

Here’s the problem: because M dwarfs are so faint, the habitable zone is very, very close to the star itself. Proxima b sits a mere 7.5 million kilometers (4.7 million miles) from Proxima Centauri—nearly ten times closer than Mercury orbits the Sun.

In such a tight orbit, a few things can happen. For one, the planet can become tidally locked, with a permanent day and night side, which could trigger strong atmospheric winds and some wild climate dynamics.

What’s more, many M dwarf stars, including Proxima Centauri, produce powerful flares that spew bursts of harmful radiation into space daily. As the authors of the new exoplanet discovery paper note, Proxima b suffers x-ray fluxes approximately 400 times greater than what we experience here on Earth. According to Kaltenegger, Proxima Centauri’s energetic outbursts are likely to deliver a lot of DNA-damaging UV radiation to the surface, as well.

Biofluorescence in fish. Image: Wikimedia

Could life survive on such a world? If it lived deep underground, maybe. Unfortunately for us, that would make the chances of detecting its fingerprints from afar quite slim.

But as Kaltenegger and Jack O’Malley James argue in their new paper, which has been submitted toThe Astrophysical Journal, there may be another way. Certain reef-building corals contain proteins capable of absorbing UV radiation and reemitting its energy at a longer, safer wavelengths; a process known as biofluorescence. By “downshifting” the sun’s harshest rays, it is believed that corals are able to protect their symbiotic algal partners from UV damage.

Biofluorescence is not unique to coral—it’s evolved independently across the tree of life on several occasions, suggesting that its adaptive advantages are pervasive.

Inspired by this observation, O’Malley James and Kaltenegger set about to determine whether a biofluorescent life form could produce a remotely detectable trace on an alien world orbiting an active M dwarf star. Using fluorescent coral proteins, they modeled the spectral signature of a planet with an Earth-like atmosphere in the habitable zone.

They found that if biofluoresence were present across the planet’s surface, either in land-based life forms or shallow ocean basins, the planet would produce a distinct, short-lived biosignature during a UV-flare. Essentially, life would cause the planet to glow. “You can envision an ocean world that gets struck by a UV flare, and all of a sudden it lights up,” Kaltenegger said.

It’s certainly a beautiful idea—but would biofluoresence offer our radiation-hardy aliens enough protection on a world like Proxima b? Nobody has the answer, in part because we don’t yet know how much UV radiation hits the planet’s surface. But in laboratory experiments, bioengineers have succeeded in pushing the efficiency of UV fluorescent proteins to 100 percent. Given a high-radiation environment, it stands to reason that natural selection might do the same.

Coral biologist and biofluorescence expert Charles Mazel emphasized that while the mechanism Kaltenegger and O’Malley James propose is plausible, an organism might also cope with high UV by dissipating the energy as heat, or by putting it to work in its cell, similar to how plants harness visible light for photosynthesis. “The fluorescence idea is one of several possible strategies,” he told Gizmodo in an email. “Probable? Not possible for me to say. Possible? I suppose possible.”

What’s most exciting about this idea is that astronomers might be able to detect the glow of alien life on a nearby exoplanet within a few years, thanks to the next generation of extremely large telescopes. And if we do wind up catching some tantalizing glimmers of activity on Proxima b? All the more reason for Breakthrough Starshot to re-route its interstellar voyage.

First announced by Stephen Hawking and Yurni Milner earlier this year, the effort to send a fleet of nanocraft to Alpha Centauri within a generation could be in for a slight course correction, depending on what we learn about the Proxima Centauri system in the years to come.

“What I find so amazing [about Breakthrough Starshot] is that is has become okay to talk about interstellar travel,” Kaltenegger said. “People are now seriously considering it. I think the inspiration that comes from talking about this, and putting the technology within reach, will be an amazing thing.”

Maddie is a staff writer at Gizmodo

How Aluminum Changed the World

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How Aluminum Changed the World

Yesterday 3:10pm

Aluminum started as one of the world’s most expensive materials because it was difficult to refine—even though it made up 8 percent of the world’s crust. But eventually aluminum became one of the cheapest materials after methods of mass producing it were invented in the 1880s. It went from $1200 per kilogram down to a dollar in 50 years.

The aluminum used back then was still weak and malleable, though. It wasn’t until Alfred Wilm accidentally discovered age-hardening which transformed aluminum to duralumin, an alloy with a much stronger crystalline structure, that things began to change. Duralumin was used to create the first all-metal airplane, and its strength eventually led to new plane structures being built that changed air travel forever.

Real Engineering goes through the history of aluminum and makes the case that it’s one of those materials in history that completely changed the world. The video cites other examples for aluminum’s importance, like how its lightness is favored in power lines (even though copper is a better conductor) and how its used in construction. There’s a damn fun history for such an interesting material.

Flooding in Louisiana

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Flooding in Louisiana

Louisiana continues to deal with the disastrous affects of historic flooding that killed at least 17 and destroyed about 60,000 homes.–By Leanne Burden Seidel
Leslie Andermann Gallagher surveys the flood damage to her home on Aug. 17 in Sorrento, Louisiana. Last week Louisiana was overwhelmed with flood water causing at least thirteen deaths and thousands of homes damaged by the flood waters. (Joe Raedle/Getty Images)
Evacuees take advantage of the shelter setup in the The Baton Rouge River Center arena as the area deals with the record flooding that caused thousands of people to seek temporary shelters on Aug. 19, in Baton Rouge, La. (Joe Raedle/Getty Images)
President Barack Obama hugs Marlette Sanders as he tours Castle Place, a flood-damaged area of Baton Rouge, La., on Aug. 23. Obama is making his first visit to flood-ravaged southern Louisiana as he attempts to assure the many thousands who have suffered damage to their homes, schools and businesses that his administration has made their recovery a priority. (Susan Walsh/Associated Press)
Dee Vazquez, from left, helps Georgette Centelo and her grandfather Lawrence Roberts after they tried to recover their belongings from a family mobile home in Central, north of Baton Rouge, La., Aug. 15. (David Grunfeld/ The Times-Picayune via AP)
Flooded areas of Baton Rouge are seen from the air. As many as 30,000 people have been rescued following unprecedented floods. (Melissa Leake/AFP/Getty Images)
Sandra Montanaro holds her dog Dixy during one of two 20-minute daily visits at a temporary animal shelter the Lamar Dixon Expo Center near a flood victims shelter, Aug. 16, in Gonzales, La. (Brendan Smialowski/AFP/Getty Images)
Daniel Stover, 17, moves a boat of personal belongings from a friend’s home flooded home in Sorrento, La., Aug. 20. (Max Becherer/Associated Press)
Members of the Louisiana Army National Guard load 3-month-old baby Ember Blount onto a truck as they rescue people from rising floodwater near Walker, La., after heavy rains inundated the region, Aug. 14. (Max Becherer/Associated Press)
Piles of debris are seen in front of flood damaged homes in St. Amant, La, Aug. 21. (Jonathan Bachman /Reuters)
Lester Duplessis walks down a flooded street to his house Aug.16 in Gonzales, La. (Brendan Smialowski/AFP/Getty Images)
Melissa Gouda removes flood damaged items out of a friend’s house in St. Amant, La., ,Aug. 21. (Jonathan Bachman /Reuters)
Joey Gregory’s reflection is seen in flood water as he walks on top of sand bags in St. Amant, La., Aug. 20. (Jonathan Bachman/Reuters)
Katy Bueche and Chris Villnuve wait for a boat ride to salvage items from their flooded homes on Aug. 18, in Sorrento, La. (Joe Raedle/Getty Images)
People sort through water damaged products outside Jasmine’s Beauty Supply following the floods on Aug. 16, in Baton Rouge. (Brendan Smialowski/AFP/Getty Images)
Bryce Richard waits for a load of clothes from Blake Waguespack as they fill a boat with items they are salvaging from a friends flooded home on Aug.18, in Sorrento, La (Joe Raedle/Getty Images)
A water logged picture in a home that was inundated with flood waters on Aug. 19, in St Amant, La. (Joe Raedle/Getty Images)
Cattle huddle together in the water, caused by flooding after the heavy rains in Ascension Parish, in St. Amant, south of Baton Rouge in Aug. 16. (Bill Feig/The Advocate via AP)
A man navigates a boat of rescued goats past a partially submerged car after flooding on Aug. 16, in Gonzales, La. (Brendan Smialowski/AFP/Getty Images)
Damaged products are seen at Jasmine’s Beauty Supply following the floods on Aug. 16, in Baton Rouge, La. (Brendan Smialowski/AFP/Getty Images)
Travis Guedry and his dog Ziggy glide through floodwaters keeping an eye out for people in need on Aug. 17, in Sorrento, La. (Joe Raedle/Getty Images)
A statue of the Virgin Mary is seen partially submerged in flood water as it rains in Sorrento, La., Aug. 20. (Jonathan Bachman/Reuters)
Billy Bethley throws flood damaged floor board on to a pile of debris in Prairieville, La., Aug. 22. (Jonathan Bachman/Reuters)
David McNeely (L) and Jason Schexnayder walk through a flooded street, as morning fog blankets the area on Aug. 17, in Sorrento, La. (Joe Raedle/Getty Images)
Mud covered belongings are seen on the floor of a home after flood water receded Aug. 17, in Denham Springs, La. (Brendan Smialowski/AFP/Getty Images)
Boats sail on Highway 431, flooded after heavy rains in the Ascension Parish area, south of Baton Rouge, La., Aug. 16. (Bill Feig/The Advocate via AP)
Families displaced by flooding are unloaded on dry ground after being rescued from the Hebron Baptist Church by the Louisiana Army National Guard in Walker, La., Aug. 15. About 200 people were taken to the church by the fire department when they became stranded as flood waters continued to rise. (Max Becherer/Associated Press)
Mehmoud Elodeh walks over damaged merchandise as he checks on a clothing and shoe store following the floods on August 16, in Baton Rouge. (Brendan Smialowski/AFP/Getty Images)
Raymond Lieteau waits for help to move a refrigerator as his friend Melissa Lockhart, left, helps clean up the living room in his flood damaged home in Baton Rouge, La., Aug. 16. Lieteau had more than five feet of water in his home. (Max Becherer/Associated Press)
A boy rides his bike inside the flood damaged Life Tabernacle Church on Aug. 15, in Baton Rouge, La. (Brendan Smialowski/AFP/Getty Images)
Rescue officials and civilians rescue people from their flooded homes along the Tangipahoa River near Amite, La., Aug. 13. (Ted Jackson/ The Times-Picayune )
Trina Staford throws one of her scrapbooks out of her childhood home while helping her mother clean out her flood damaged home Aug. 17, in Walker, La. (Brendan Smialowski/AFP/Getty Images)
Tony Fresina works to clean his flood damaged kitchen in Prairieville, La, U.S., Aug. 22. (Jonathan Bachman/REuters)
Pastor Mark Carroll, right, listens to the prayers of Valerie St. Romain, 35, during church services at South Walker Baptist Church in Walker, La., Aug. 21. Outside the small town of Walker, Louisiana, the rural Baptist church has become an oasis for flood victims. (Max Becherer/Associated Press)
A man throws flood damaged material into a pile of debris in St. Amant, La, Aug. 21. (Jonathan Bachman/Reuters)
A family of deer make their way through flood waters on Aug. 16, in Gonzales, La. (Brendan Smialowski/AFP/Getty Images)
The motorcade of Republican presidential candidate Donald Trump passes piles of rubbish on the side of the road in East Baton Rouge, La., Aug. 19. (Max Becherer/Associated Press)
Samantha Labatut cleans out a refrigerator inside her flood damaged kitchen in St. Amant, La., Aug. 21. (Jonathan Bachman/Reuters)
A casket is seen floating in flood waters in Ascension Parish, La, U.S., Aug.15. (Jonathan Bachman/Reuters)
Chad Credeur helps his brother Karl Credeur (R) toss out a headboard after it was inundated with flood water in his bedroom on Aug.18, in St Amant, La. (Joe Raedle/Getty Images)
Gulfport, Miss., firefighters load water and cleaning supplies donated by Bayou View Elementary School families in Gulfport for flood victims in Louisiana. (John Fitzhugh/The Sun Herald via AP)
Chickens are seen in a flooded coop in a neighborhood inundated with flood waters on Aug. 17, in Sorrento, La. (Joe Raedle/Getty Images)
Wade Houston cleans out his mother’s home after flooding Aug. 17, in Denham Springs, La. (Brendan Smialowski/AFP/Getty Images)
Collan Ortego (L) gets help from Jason Fatherree as he retrieves a television set from his family’s flooded home on Aug. 17 in Sorrento, La. (Joe Raedle/Getty Images)
John Booth (L) sits with Angela Latiolais’s (2L) family while helping them save belongings after flooding on August 16, in Gonzales, La. (Brendan Smialowski/AFP/Getty Images)
A resident wades through flood water at Tiger Manor Apartments by the North Gates of LSU, Aug. 13, in Baton Rouge, La. (Brianna Paciorka/The Advocate via AP)

Deadly earthquake hits Italy

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Deadly earthquake hits Italy

Search and rescue crews are using whatever they can to locate survivors from a magnitude 6.2 earthquake that reduced three central Italian towns to rubble early today. The death toll stood at 120, but certainly will rise said officials. ‘‘The town isn’t here anymore,’’ said Sergio Pirozzi, the mayor of the hardest-hit town, Amatrice.–By Lloyd Young
A man is rescued from the ruins following an earthquake in Amatrice, central Italy, on Aug. 2. (Remo Casilli/Reuters)
Search and rescue teams survey the rubble in Amatrice, central Italy, following a 6.2 magnitude earthquake according to the United States Geological Survey (USGS), that struck at around 3:30 am. The quake was felt across a broad section of central Italy, including the capital Rome where people in homes in the historic center felt a long swaying followed by aftershocks. (Massimo Percossi/EPA)
A woman holds a child as they stand in the street following an earthquake in Amatrice. (Massimo Percossi/ANSA via Associated Press)
This aerial photo shows the historical part of the town of Amatrice, central Italy, after the quake on Aug. 24. (Gregorio Borgia/Associated Press)
Rescue and emergency services personnel carry a survivor on a stretcher during search and rescue operations in Amatrice on Aug. 24 after a powerful earthquake rocked central Italy. The quake rattled a remote area of central Italy, leaving at least 120 people dead and and some 368 injured amongst scenes of carnage in mountain villages. (Filippo Monteforte/AFP/Getty Images)
An aereal view of collapsed and damaged houses due to the earthquake in Pescara del Tronto, central Italy. (Guardia Di Finanza Press Office via EPA /)
A man is pulled out of the rubble following an earthquake in Amatrice. (Massimo Percossi/ANSA via Associated Press)
Residents reacts among the rubble after a strong earthquake hit Amatrice on Aug. Numerous buildings had collapsed in communities close to the epicenter of the quake near the town of Norcia in the region of Umbria, witnesses told Italian media, with an increase in the death toll highly likely. (Filippo Monteforte/AFP/Getty Images)
A man reacts to his damaged home after a strong quake hit Amatrice. (Filippo Monteforte/AFP/Getty Images)
A rescued woman is carried away on a stretcher following an earthquake in Amatric. The magnitude 6.2 quake struck at 3:36 am and was felt across a broad swath of central Italy. (Massimo Percossi/ANSA via Associate Press)
A rescuer walks a sniff dog as they search through the debris of collapsed houses following an earthquake in Amatrice. (Alessandra Tarantino/Associated Press)
Residents are seen in front of collapsed houses in Amatrice, central Italy. (Massimo Percossi/EPA)
A woman looks at damaged buildings after a strong earthquake hit central Italy, in Amatrice on Aug. 24. A powerful 6.2-magnitude earthquake devastated mountain villages in central Italy on Wednesday, leaving at least 120 people dead and dozens more injured or unaccounted for. (Filippo Monteforte/AFP/Getty Images)
A man leans on a wall as the collapsed village of Pescara del Tronto, central Italy, is seen behind him. (Crocchionii/ANSA via Associated Press)
A man walks amid rubbles after an earthquake struck in Amatrice Italy, on Aug. 24. (Alessandra Tarantino/Associated Press)
A nun checks her mobile phone as she lies near a ladder following an earthquake in Amatrice, Italy. (Massimo Percossi/Associated Press)
Rescuers work on collapsed buildings following an earthquake in Amatrice, central Italy, on Aug. 24. (Ciro De Luca/Reuters)
A man is carried away on a stretcher after being pulled from the rubble of a collapsed house in Fonte del Campo near Accumoli, central Italy. (Angelo Carconi/EPA)
Rescuers work among the debris of collapsed houses following an earthquake in Pescara Del Tronto on Aug. 24. (Andrew Medichini/Associated Press)
Rescuers recover a lifeless body from a collapsed house following an earthquake in Pescara Del Tronto, Italy. (Gregorio Borgia/Associated Press)
An injured man is rescued from the rubble by emergency teams in Amatrice, central Italy, following a 6.2 magnitude earthquake, according to the United States Geological Survey. (Massimo Percossi/EPA)
Rescuers search through debris of collapsed houses following an earthquake in Pescara del Tronto, Italy. (Sandro Perozzi/Associated Press)
Rubble of a building collapsed in Amatrice, central Italy, where a earthquake struck just after 3:30 a.m. in Amatrice, Italy, on Aug. 24. (Massimo Percossi/EPA)
People hold a blanket as they prepare to spend the night in the open following the earthquake in Amatrice, central Italy, on Aug. 24. (Stefano Rellandini/Reuters)
An excavator clears rubble following an earthquake in Pescara Del Tronto, Italy. (Gregorio Borgia/Associated Press)

Power Station Worker’s Private Collection Yields Bronze Age Treasures

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Tia Ghose, Senior Writer, Wed, Aug 24 5:59 AM PDT

A man who spent many years collecting metal artifacts from the ocean near the power plant where he worked in Israel secretly amassed a huge collection of valuable and ancient treasures.

Archaeologists were recently given the trove of artifacts after the man, who had worked for years at the Orot Rabin Power Station in Hadera, on the coast of Israel, passed away and his family began sorting through his belongings. They found a remarkable collection of valuable and ancient items.

“The finds include a toggle pin and the head of a knife from the Middle Bronze Age,” which are more than 3,500 years old, Ayala Lester, a curator with the Israel Antiquities Authority, said in a statement. [The Holy Land: 7 Amazing Archaeological Finds]

The man’s collection also included valuable mortars and pestles, candlestick fragments and other goods manufactured during the Fatimid Dynasty from the 11th century. The items were probably made in Syria.

“The finds are evidence of the metal trade that was conducted during this period,” Lester said.

Amateur collector

The power plant worker, Marcel Mazliah, had been employed at the Orot Rabin Power Station since it was first constructed in 1973. The coal-fired plant, which is Israel’s largest, lies on the banks of the Mediterranean, and over the years, Mazliah had been quietly collecting objects washed up from the sea.

After Mazliah’s death, his family asked representatives from the Israel Antiquities Authority to look at his treasure collection. As it turned out, the collection contained genuine artifacts that were likely lost from a metal merchant’s ship at some point in the past.

In addition to the stunning Bronze Age pin and the Fatimid-era treasures, the collection also included an ancient hand grenade of a type used by the Crusaders, Ayyubids and the Mamluks hundreds of years ago.

Mazliah’s family will receive a certificate of appreciation for handing over the artifacts to the Israel Antiquities Authority.

With hundreds of civilizations occupying the region over the millennia, Israel is full of ancient artifacts, many of which have been discovered by accident by ordinary citizens. For instance, in 2015, cavers found a trove of ancient coins and jewelry, while that same year an unsuspecting Israeli family found a historic ritual bath lurking beneath the floorboards of their apartment.

Original article on Live Science.

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Italy earthquake: Before and after images show destruction

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Italy earthquake: Before and after images show destruction

  • 4 hours ago
  • From the sectionEurope
Rescuers in Amatrice, Italy on 24 August 2016Image copyrightAP

A strong earthquake has devastated a string of mountain towns and villages in central Italy, killing more than 240 people and leaving many unaccounted for.

The 6.2 magnitude quake, which was followed by several aftershocks, struck at 03:36 (01:36 GMT) on Wednesday, 100km (65 miles) north-east of Rome.

Worst affected were the towns of Accumoli and Amatrice and the village of Pescara del Tronto.

Map showing severity of Italy earthquake

The first confirmed deaths following the quake came in Amatrice, when search teams found two bodies amid the rubble.

The town’s mayor, Sergio Pirozzi, told the AP news agency that more than a dozen victims had been discovered by rescuers, but added: “I believe the number will rise.”

The earthquake badly damaged the centre of Amatrice, shown in these two pictures of the same street before and after the quake - 24 August 2016
Image copyrightGOOGLE/AP
Image captionThe main street through Amatrice was reduced to rubble following the earthquake
This aerial photo shows the damaged buildings in the centre of Amatrice - 24 August 2016
Image copyrightAP
Image captionThe clock tower in the town centre was left standing but many of the surrounding buildings were not
An image of a house in Amatrice before and after the earthquake in central Italy – 24 August 2016
Image copyrightGOOGLE/REUTERS
Image captionMany homes in and around the small town were completely destroyed by the tremors
A church in Amatrice before and after it wasbadly damaged by an earthquake in central Italy - 24 August 2016
Image copyrightGOOGLE/AFP
Image captionA church in the town was also badly damaged, losing much of the top of the building and its roof

In Accumoli, a small mountain town, the first victims were a family of four who were found under the debris of a collapsed building.

Mayor Stefano Petrucci told reporters: “We have a tragedy here. There are people under the ruins.”

He said the town of just 700 residents swells to 2,000 in the summer months thanks to tourism, but that he feared for its future after the earthquake.

“I hope they don’t forget us,” he told the Sky TG24 broadcaster.

A building in the centre of Accumoli before and after the earthquake - 24 August 2016
Image copyrightGOOGLE/REUTERS
Image captionA residential building in the heart of Accumoli that was partially destroyed by the quake
Firefighters search amid rubble following an earthquake in Accumoli, central Italy - 24 August 2016
Image copyrightAP
Image captionAccumoli Mayor Stefano Petrucci said some hundreds of people had been left homeless

The village of Pescara del Tronto was also badly hit, with the Italian news agency ANSA reporting that at least 10 people had been killed there.

The main road into and out of the town was covered in debris, making it difficult for search and rescue teams to gain access to some damaged areas.

An image of some of the damage on the Via Salaria road in Pescara del Tronto compared to an image of the street before the quake - 24 August 2016

Image copyrightGOOGLE/EPA
Image captionOne section of the road into Pescara del Tronto was almost entirely destroyed

A general view of Pescara del Tronto town destroyed by the earthquake - 24 August 2016

Image copyrightGETTY IMAGES
Image captionPhotos taken from the air by regional firefighters showed much of the town flattened

Quake damage in Amatrice (24 August 2016)

Amatrice: Most of the pretty, historic town is now rubble, blanketed in grey dust

Home exposed by quake in Amatrice, 25 Aug 16

The interior of a home in Amatrice exposed by the quake

Rescuers said they had pulled five bodies from the ruins of the Hotel Roma in Amatrice. As many as 70 tourists were staying at the hotel when the quake struck. Many are feared to be in the rubble, though several were pulled out and given medical care.

Many of those affected were Italians on holiday in the region. Some were in Amatrice for a festival to celebrate a famous local speciality – amatriciana bacon and tomato sauce.

Late on Wednesday there were cheers in the village of Pescara del Tronto when a young girl was pulled alive from the rubble after being trapped for 17 hours. Almost all the houses there had collapsed, the mayor said.

Why is Italy at risk of earthquakes? By Jonathan Amos

Earthquakes are an ever-present danger for those who live along the Apennine mountain range in Italy.

Through the centuries thousands have died as a result of tremors equal to, or not much bigger than, the event that struck in the early hours of Wednesday. The modern response, thankfully, has been more robust building and better preparation.

Map showing the earthquake and its aftershocks in central Italy - 24 August 2016

Mediterranean seismicity is driven by the great collision between the African and Eurasian tectonic plates; but when it comes down to the specifics of this latest quake, the details are far more complicated.

The Tyrrhenian Basin, or Sea, which lies to the west of Italy, between the mainland and Sardinia/Corsica, is slowly opening up.

Scientists say this is contributing to extension, or “pull-apart”, along the Apennines. This stress is compounded by movement in the east, in the Adriatic.

The result is a major fault system that runs the length of the mountain range with a series of smaller faults that fan off to the sides. The foundations of cities like Perugia and L’Aquila stand on top of it all.

Quakes ‘ever present’ for Italy’s Apennines


Attack on American University in Kabul Ends, 12 Dead

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MICHAEL EDISON HAYDEN and DAVID CAPLAN,Good Morning America–abc-news-topstories.html

A deadly attack on the American University of Afghanistan in Kabul has ended, according to a government spokesperson.

General Abdul Rahman Rahimi, Kabul’s police chief, said early Thursday that 12 people were killed. Of the 12 killed, he said 7 were students, 3 were police officers and 2 were American University of Afghanistan guards.

Rahimi said 35 students and 9 police officers were injured.

There were no immediate claims of responsibility for the attack. Although suspicion falls on the Taliban, the group’s spokesman, Zabihullah Mujahid, would only tell the media that the group is “investigating,” according to The AP.

Three attackers were involved in the attack, Rahimi said. The first attacker detonated a suicide car bomb at the entrance the other two managed to enter the campus, he said.

(Rahmat Gul/AP Photo)

Interior Ministry spokesman Sediq Sediqqi said the attackers were armed with grenades and automatic weapons. The siege of the university lasted almost nine hours, before police killed the two assailants around 3.30 am, he said.

“Most of the dead were killed by gun shots near the windows of their classrooms,” Sediqqi said.

More than 150 students who had been trapped in university buildings were rescued by special police units, according to The AP.

The U.S. State Department acknowledged reports Wednesday morning of the attack on an official Twitter account, posting, “Reports of attack on American University in Kabul. Exercise caution, avoid unnecessary movement in the area & monitor news for updates.”

State Department Director of Office of Press Relations Elizabeth Trudeau later read a statement saying that they “condemn this attack in the strongest possible terms.”

“An attack on a university is an attack on the future of Afghanistan. Our embassy in Kabul, as well as our NATO counterparts of the Resolute Support Mission, are closely monitoring the situation as we are. We understand this situation is ongoing.

“We do understand there are small numbers of Resolute Support advisers who are assisting their Afghan counterparts as Afghan forces are responding as this situation develops. These advisers are not taking a combat role but advising Afghan counterparts,” she said.

“We are in the process of accounting for all chief of mission personnel and working to locate and assist any U.S. citizens affected by these attacks. The U.S. embassy in Kabul did issue a security message warning U.S. citizens of the attack and advising them to avoid the area until further notice. Our travel warning for Afghanistan warns U.S. citizens against travel to Afghanistan because of the continued instability and threats by terror attacks against U.S. citizens,” she said.

Massoud Hossaini, a photographer for The Associated Press, tweeted that he was trapped inside during the attack.

“Help we are stuck inside AUAF and shooting flollowed [sic] by Explo this maybe my last tweets,” he wrote.

The AP later reported that he was safe and had escaped from the school.

The attackers managed to enter Noor Hospital, adjacent to the school, according to eyewitnesses.

The American University of Afghanistan opened in 2006 and was a pet project of former first lady Laura Bush, who helped launch the institution on a 2005 visit to Kabul, the capital.

Much of its funding has come from the U.S. Agency for International Development, which administers civilian foreign aid, and today the school has more than 1,700 full- and part-time students. It has produced 29 Fulbright scholars and maintains partnerships with many U.S. colleges, such as Stanford, Georgetown and the University of California system.

The school says on its website that it “embraces diversity and community” in Afghanistan.

But it has been no stranger to threats of violence since its creation.

Two professors at the university — one American and one Australian — were abducted at gunpoint outside the campus earlier this month, underscoring the deteriorating security situation in the capital and across the rest of the country.

Also, two people employed by the university were killed in 2014 when a suicide bomber set off an explosion in a Kabul restaurant that was popular with expats.

ABC News’ Aleem Agha and Jon Williams contributed to this report. The Associated Press also contributed to this report.

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