Millennia ago, eclipses provided rare opportunities to measure the universe

Tyler Nordgren writes: As a kid visiting the Oregon coast I often wondered, “How wide is the ocean, and what is there beyond the horizon?” As I grew older and turned my sights to the night sky, I wondered something very similar: “How far away are the stars, and are there other planets there?” Even though very few of us have ever circumnavigated the globe, and no human being has ever ventured into space beyond the moon, we do know some of the answers to these questions. Immensity isn’t immeasurable. While these vast numbers may make little sense in our daily lives, we at least know they are known.

Consider what it must have been like to live in a world where this was not true: where the sense of immeasurability, the certainty of the unfathomable, was commonplace, and the thought that the world could be known was a novel idea. The philosopher Anaxagoras was born in about 500 B.C. in the eastern Mediterranean on what is now the coast of Turkey. It was a time when philosophy had only recently turned its attention to the natural world. Less than a hundred years before, Thales of Miletus supposedly predicted the solar eclipse that ended a war, thus implying that our world was predictable and events were not just the random whims of the gods.

In such a world of physical phenomena, Anaxagoras was the first, as far as we know, to understand that eclipses occur when one heavenly body blocks the light from another. This rejection of gods and dragons as the causes of eclipses was a revolutionary thought by itself, but Anaxagoras took it further: If solar eclipses happened only because the Earth had moved into the shadow of the moon, he reasoned, then the size of the shadow must tell us something about the size of the moon. Additionally, since the moon covered the sun, the sun must be farther away. Yet to appear nearly the same size, the sun must be larger than the moon. Herein lies the power of scientific thought: Measure the extent of the shadow sweeping across the Earth, and you know the moon must be at least as big as the shadow, and the sun larger still. Mysticism provided no such opportunity: If eclipses occur when a demon devours the sun, there is no reason to believe that any measurement we make here on Earth should reveal the demon’s size.[Continue reading…]

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Moon had a magnetic field for at least a billion years longer than thought

Science News reports: The moon had a magnetic field for at least 2 billion years, or maybe longer.

Analysis of a relatively young rock collected by Apollo astronauts reveals the moon had a weak magnetic field until 1 billion to 2.5 billion years ago, at least a billion years later than previous data showed. Extending this lifetime offers insights into how small bodies generate magnetic fields, researchers report August 9 in Science Advances. The result may also suggest how life could survive on tiny planets or moons.

“A magnetic field protects the atmosphere of a planet or moon, and the atmosphere protects the surface,” says study coauthor Sonia Tikoo, a planetary scientist at Rutgers University in New Brunswick, N.J. Together, the two protect the potential habitability of the planet or moon, possibly those far beyond our solar system.

The moon does not currently have a global magnetic field. Whether one ever existed was a question debated for decades (SN: 12/17/11, p. 17). On Earth, molten rock sloshes around the outer core of the planet over time, causing electrically conductive fluid moving inside to form a magnetic field. This setup is called a dynamo. At 1 percent of Earth’s mass, the moon would have cooled too quickly to generate a long-lived roiling interior.

Magnetized rocks brought back by Apollo astronauts, however, revealed that the moon must have had some magnetizing force. The rocks suggested that the magnetic field was strong at least 4.25 billion years ago, early on in the moon’s history, but then dwindled and maybe even got cut off about 3.1 billion years ago. [Continue reading…]

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Climate report could force Trump to choose between science and his anti-science supporters

The New York Times reports: The impending release of a key government report on climate change will force President Trump to choose between accepting the conclusions of his administration’s scientists and the demands of his conservative supporters, who remain deeply unconvinced that humans are the cause of the planet’s warming.

A White House official said on Tuesday that it was still reviewing the draft document that was written by scientists, some of whom have said they fear Mr. Trump will seek to bury it or alter its contents before it is formally released. Sarah Huckabee Sanders, the White House press secretary, said the administration would not comment on the report before its scheduled release this fall.

But the looming publication of the climate report — which concludes that “evidence for a changing climate abounds, from the top of the atmosphere to the depths of the oceans” — once again raises a contentious policy issue that has deeply divided Mr. Trump’s closest advisers since he arrived in the Oval Office. [Continue reading…]

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A new technology for detecting neutrinos represents a ‘monumental’ advance for science

Scientific American reports: Neutrinos are famously antisocial. Of all the characters in the particle physics cast, they are the most reluctant to interact with other particles. Among the hundred trillion neutrinos that pass through you every second, only about one per week actually grazes a particle in your body.

That rarity has made life miserable for physicists, who resort to building huge underground detector tanks for a chance at catching the odd neutrino. But in a study published today in Science, researchers working at Oak Ridge National Laboratory (ORNL) detected never-before-seen neutrino interactions using a detector the size of a fire extinguisher. Their feat paves the way for new supernova research, dark matter searches and even nuclear nonproliferation monitoring.

Under previous approaches, a neutrino reveals itself by stumbling across a proton or neutron amidst the vast emptiness surrounding atomic nuclei, producing a flash of light or a single-atom chemical change. But neutrinos deign to communicate with other particles only via the “weak” force—the fundamental force that causes radioactive materials to decay. Because the weak force operates only at subatomic distances, the odds of a tiny neutrino bouncing off of an individual neutron or proton are minuscule. Physicists must compensate by offering thousands of tons of atoms for passing neutrinos to strike. [Continue reading…]

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Half the atoms inside and around us came from outside the Milky Way

The Guardian reports: Nearly half of the atoms that make up our bodies may have formed beyond the Milky Way and travelled to the solar system on intergalactic winds driven by giant exploding stars, astronomers claim.

The dramatic conclusion emerges from computer simulations that reveal how galaxies grow over aeons by absorbing huge amounts of material that is blasted out of neighbouring galaxies when stars explode at the end of their lives.

Powerful supernova explosions can fling trillions of tonnes of atoms into space with such ferocity that they escape their home galaxy’s gravitational pull and fall towards larger neighbours in enormous clouds that travel at hundreds of kilometres per second.

Astronomers have long known that elements forged in stars can travel from one galaxy to another, but the latest research is the first to reveal that up to half of the material in the Milky Way and similar-sized galaxies can arrive from smaller galactic neighbours.

Much of the hydrogen and helium that falls into galaxies forms new stars, while heavier elements, themselves created in stars and dispersed in the violent detonations, become the raw material for building comets and asteroids, planets and life. [Continue reading…]

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Trump nominates right-wing talk radio host for leading scientific position at USDA

Gizmodo reports: President Donald Trump managed to sneak a few minutes from his busy schedule of threatening federal investigators to make official his nominee for the United States Department of Agriculture’s top scientific position on Wednesday. Given the tough choice between filling the role with scientist or someone who is not a scientist, the president boldly decided to go the latter route.

Enter Sam Clovis, who Trump first installed at the USDA as a senior White House adviser earlier this year, and if confirmed will serve as the agency’s undersecretary for research, education and economics. That’s an important scientific job previously held by top scientists in biochemistry, medicine, food nutrition and ecosystem ecology. The person in that job is charged with directing the USDA’s extensive scientific mission, which includes everything from preparing U.S. agriculture to deal with climate change to advising on nutrition and food-borne pathogen outbreaks.

Clovis, as ProPublica noted back in May, has a resume which includes working as co-chair and policy adviser on Trump’s campaign, but very little that could be called science. His doctorate is in public administration, and his record of published academic work includes a handful of journal articles mostly on national security and terrorism.

ProPublica could not find any evidence he had scientific credentials or even took graduate-level courses in “food safety, agriculture or nutrition,” while he told E&E News in 2016 Trump’s USDA would primarily focus on slashing regulation

In his native Iowa, Clovis is mostly known for hosting a right-wing talk show. While running for the U.S. Senate in 2014, he told Iowa Public Radio he was “extremely skeptical” of the 97% consensus among climate scientists that mankind is responsible for global warming, adding, “I have looked at the science and I have enough of a science background to know when I’m being boofed. And a lot of the science is junk science.” [Continue reading…]

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I’m a scientist. I’m blowing the whistle on the Trump administration

Joel Clement writes: I am not a member of the deep state. I am not big government.

I am a scientist, a policy expert, a civil servant and a worried citizen. Reluctantly, as of today, I am also a whistleblower on an administration that chooses silence over science.

Nearly seven years ago, I came to work for the Interior Department, where, among other things, I’ve helped endangered communities in Alaska prepare for and adapt to a changing climate. But on June 15, I was one of about 50 senior department employees who received letters informing us of involuntary reassignments. Citing a need to “improve talent development, mission delivery and collaboration,” the letter informed me that I was reassigned to an unrelated job in the accounting office that collects royalty checks from fossil fuel companies.

I am not an accountant — but you don’t have to be one to see that the administration’s excuse for a reassignment such as mine doesn’t add up. A few days after my reassignment, Interior Secretary Ryan Zinke testified before Congress that the department would use reassignments as part of its effort to eliminate employees; the only reasonable inference from that testimony is that he expects people to quit in response to undesirable transfers. Some of my colleagues are being relocated across the country, at taxpayer expense, to serve in equally ill-fitting jobs.

I believe I was retaliated against for speaking out publicly about the dangers that climate change poses to Alaska Native communities. During the months preceding my reassignment, I raised the issue with White House officials, senior Interior officials and the international community, most recently at a U.N. conference in June. It is clear to me that the administration was so uncomfortable with this work, and my disclosures, that I was reassigned with the intent to coerce me into leaving the federal government. [Continue reading…]

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Congressman Rohrabacher wants to know whether there was an ancient civilization on Mars

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Maryam Mirzakhani, only woman to win a Fields Medal, dies at 40

The New York Times reports: Maryam Mirzakhani, an Iranian mathematician who was the only woman ever to win a Fields Medal, the most prestigious honor in mathematics, died on Saturday. She was 40.

The cause was breast cancer, said Stanford University, where she was a professor. The university did not say where she died.

Her death is “a big loss and shock to the mathematical community worldwide,” said Peter C. Sarnak, a mathematician at Princeton University and the Institute for Advanced Study.

The Fields Medal, established in 1936, is often described as the Nobel Prize of mathematics. But unlike the Nobels, the Fields are bestowed only on people aged 40 or younger, not just to honor their accomplishments but also to predict future mathematical triumphs. The Fields are awarded every four years, with up to four mathematicians chosen at a time.

“She was in the midst of doing fantastic work,” Dr. Sarnak said. “Not only did she solve many problems; in solving problems, she developed tools that are now the bread and butter of people working in the field.”

Dr. Mirzakhani was one of four Fields winners in 2014, at the International Congress of Mathematicians in South Korea. Until then, all 52 recipients had been men. She was also the only Iranian ever to win the award.

President Hassan Rouhani of Iran released a statement expressing “great grief and sorrow.”

He wrote, “The unparalleled excellence of the creative scientist and humble person that echoed Iran’s name in scientific circles around the world was a turning point in introducing Iranian women and youth on their way to conquer the summits of pride and various international stages.”

Dr. Mirzakhani’s mathematics looked at the interplay of dynamics and geometry, in some ways a more complicated version of billiards, with balls bouncing from one side to another of a rectangular billiards table eternally.

A ball’s path can sometimes be a repeating pattern. A simple example is a ball that hits a side at a right angle. It would then bounce back and forth in a line forever, never moving to any other part of the table.

But if a ball bounced at an angle, its trajectory would be more intricate, often covering the entire table.

“You want to see the trajectory of the ball,” Dr. Mirzakhani explained in a video produced by the Simons Foundation and the International Mathematical Union to profile the 2014 Fields winners. “Would it cover all your billiard table? Can you find closed billiards paths? And interestingly enough, this is an open question in general.” [Continue reading…]

 

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Climate change may make the planet too hot for humans sooner than you expect

David Wallace-Wells writes: It is, I promise, worse than you think. If your anxiety about global warming is dominated by fears of sea-level rise, you are barely scratching the surface of what terrors are possible, even within the lifetime of a teenager today. And yet the swelling seas — and the cities they will drown — have so dominated the picture of global warming, and so overwhelmed our capacity for climate panic, that they have occluded our perception of other threats, many much closer at hand. Rising oceans are bad, in fact very bad; but fleeing the coastline will not be enough.

Indeed, absent a significant adjustment to how billions of humans conduct their lives, parts of the Earth will likely become close to uninhabitable, and other parts horrifically inhospitable, as soon as the end of this century.

Even when we train our eyes on climate change, we are unable to comprehend its scope. This past winter, a string of days 60 and 70 degrees warmer than normal baked the North Pole, melting the permafrost that encased Norway’s Svalbard seed vault — a global food bank nicknamed “Doomsday,” designed to ensure that our agriculture survives any catastrophe, and which appeared to have been flooded by climate change less than ten years after being built.

The Doomsday vault is fine, for now: The structure has been secured and the seeds are safe. But treating the episode as a parable of impending flooding missed the more important news. Until recently, permafrost was not a major concern of climate scientists, because, as the name suggests, it was soil that stayed permanently frozen. But Arctic permafrost contains 1.8 trillion tons of carbon, more than twice as much as is currently suspended in the Earth’s atmosphere. When it thaws and is released, that carbon may evaporate as methane, which is 34 times as powerful a greenhouse-gas warming blanket as carbon dioxide when judged on the timescale of a century; when judged on the timescale of two decades, it is 86 times as powerful. In other words, we have, trapped in Arctic permafrost, twice as much carbon as is currently wrecking the atmosphere of the planet, all of it scheduled to be released at a date that keeps getting moved up, partially in the form of a gas that multiplies its warming power 86 times over.

Maybe you know that already — there are alarming stories every day, like last month’s satellite data showing the globe warming, since 1998, more than twice as fast as scientists had thought. Or the news from Antarctica this past May, when a crack in an ice shelf grew 11 miles in six days, then kept going; the break now has just three miles to go — by the time you read this, it may already have met the open water, where it will drop into the sea one of the biggest icebergs ever, a process known poetically as “calving.”

But no matter how well-informed you are, you are surely not alarmed enough. Over the past decades, our culture has gone apocalyptic with zombie movies and Mad Max dystopias, perhaps the collective result of displaced climate anxiety, and yet when it comes to contemplating real-world warming dangers, we suffer from an incredible failure of imagination. The reasons for that are many: the timid language of scientific probabilities, which the climatologist James Hansen once called “scientific reticence” in a paper chastising scientists for editing their own observations so conscientiously that they failed to communicate how dire the threat really was; the fact that the country is dominated by a group of technocrats who believe any problem can be solved and an opposing culture that doesn’t even see warming as a problem worth addressing; the way that climate denialism has made scientists even more cautious in offering speculative warnings; the simple speed of change and, also, its slowness, such that we are only seeing effects now of warming from decades past; our uncertainty about uncertainty, which the climate writer Naomi Oreskes in particular has suggested stops us from preparing as though anything worse than a median outcome were even possible; the way we assume climate change will hit hardest elsewhere, not everywhere; the smallness (two degrees) and largeness (1.8 trillion tons) and abstractness (400 parts per million) of the numbers; the discomfort of considering a problem that is very difficult, if not impossible, to solve; the altogether incomprehensible scale of that problem, which amounts to the prospect of our own annihilation; simple fear. But aversion arising from fear is a form of denial, too.

In between scientific reticence and science fiction is science itself. This article is the result of dozens of interviews and exchanges with climatologists and researchers in related fields and reflects hundreds of scientific papers on the subject of climate change. What follows is not a series of predictions of what will happen — that will be determined in large part by the much-less-certain science of human response. Instead, it is a portrait of our best understanding of where the planet is heading absent aggressive action. It is unlikely that all of these warming scenarios will be fully realized, largely because the devastation along the way will shake our complacency. But those scenarios, and not the present climate, are the baseline. In fact, they are our schedule. [Continue reading…]

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We live in a galaxy in the middle of nowhere

Evan Gough writes: Ever since Galileo pointed his telescope at Jupiter and saw moons in orbit around that planet, we began to realize we don’t occupy a central, important place in the Universe. In 2013, a study showed that we may be further out in the boondocks than we imagined. Now, a new study confirms it: we live in a void in the filamental structure of the Universe, a void that is bigger than we thought.

In 2013, a study by University of Wisconsin–Madison astronomer Amy Barger and her student Ryan Keenan showed that our Milky Way galaxy is situated in a large void in the cosmic structure. The void contains far fewer galaxies, stars, and planets than we thought. Now, a new study from University of Wisconsin student Ben Hoscheit confirms it, and at the same time eases some of the tension between different measurements of the Hubble Constant.

The void has a name; it’s called the KBC void for Keenan, Barger and the University of Hawaii’s Lennox Cowie. With a radius of about 1 billion light years, the KBC void is seven times larger than the average void, and it is the largest void we know of. [Continue reading…]

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Most Americans like science — and are willing to pay for it

Bethany Brookshire writes: Americans don’t hate science. Quite the contrary. In fact, 79 percent of Americans think science has made their lives easier, a 2014 Pew Research Center survey found. More than 60 percent of people also believe that government funding for science is essential to its success.

But should the United States spend more money on scientific research than it already does? A layperson’s answer to that question depends on how much that person thinks the government already spends on science, a new study shows. When people find out just how much — or rather, how little — of the federal budget goes to science, support for more funding suddenly jumps. [Continue reading…]

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Trump in space: ‘At some point in the future, we’re going to look back and say how did we do it without space?’

Buzz Aldrin bemused by Trump:

The Washington Post reports: President Trump’s ceremony Friday to bring back the National Space Council began to confuse people even before it took place.

It was, Trump would say, a big deal: an executive order to resurrect an advisory council that kick-started the first moon missions 60 years ago, went dormant in the 1990s, and could now lead astronauts into deep space — even Mars.

“At some point in the future, we’re going to look back and say how did we do it without space?” is how the president put it.

Yet the signing surprised many: The White House had not listed the ceremony on the president’s calendar, no one from NASA headquarters came, and the only female astronaut in attendance was left off the thank-you list.

Not to mention the president’s sometimes baffling remarks about the cosmos. [Continue reading…]

CBS News reports: The science division of the White House’s Office of Science and Technology Policy (OSTP) was unstaffed as of Friday as the three remaining employees departed this week, sources tell CBS News.

All three employees were holdovers from the Obama administration. The departures from the division — one of four subdivisions within the OSTP — highlight the different commitment to scientific research under Presidents Obama and Trump. [Continue reading…]

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Turkey drops evolution from curriculum, angering secularists

The New York Times reports: Turkey has removed the concept of evolution from its high school curriculum, in what critics fear is the latest attempt by President Recep Tayyip Erdogan’s government to erode the country’s secular character.

Starting in September, a chapter on evolution will no longer appear in ninth graders’ textbooks because it is considered too “controversial” an idea, an official announced this week.

“Our students don’t have the necessary scientific background and information-based context needed to comprehend” the debate about evolution, said the official, Alpaslan Durmus, the chairman of the Education Ministry’s Education and Discipline Board, which decides the curriculum, in a video posted on the ministry’s website.

The news has deepened concerns among Mr. Erdogan’s critics that the president, a conservative Muslim, wants to radically change the identity of a country that was founded in 1923 along staunchly secular lines. [Continue reading…]

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China makes leap toward ‘unhackable’ quantum network

The Wall Street Journal reports: Chinese scientists have succeeded in sending specially linked pairs of light particles from space to Earth, an achievement experts in the field say gives China a leg up in using quantum technology to build an “unhackable” global communications network.

The result is an important breakthrough that establishes China as a pioneer in efforts to harness the enigmatic properties of matter and energy at the subatomic level, the experts said.

In an experiment described in the latest issue of Science, a team of Chinese researchers used light particles, or photons, sent from the country’s recently launched quantum-communications satellite to establish an instantaneous connection between two ground stations more than 1,200 kilometers (744 miles) apart.

Using the quantum properties of tiny particles to create a secure communications network is scientifically and technically demanding, according to security researchers, and China is years away from being able to build one.

If China ultimately succeeds, such a system could undermine U.S. advantages in penetrating computer networks.

The Pentagon, in an annual report on China’s military delivered to Congress last week, described the quantum satellite launch in August as a “notable advance in cryptography research.”

While the U.S. is also pursuing quantum communications, it has concentrated more attention and resources on research into quantum computing. European physicists have developed many of the theories and basic practices underlying quantum encryption, but their Chinese counterparts are better-funded with government resources.

Disclosures by former National Security Agency contractor Edward Snowden in 2013 about U.S. spying on Chinese networks rattled Beijing, and have pushed the country to bolster cybersecurity measures in a variety of ways.

“The Snowden revelations undoubtedly played a part in the drive towards quantum technologies, as it revealed the degree of sophisticated threat Chinese counterespionage and cyberdefenses were facing,” said John Costello, a fellow specializing in China and cybersecurity at the nonpartisan Washington-based think tank New America. [Continue reading…]

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Life-giving chemical compound found orbiting infant stars in space

AFP reports: Two teams of astronomers said Thursday that they have for the first time detected a key chemical building block of life swirling around infant stars that resemble our sun before its planets formed.

The molecule, methyl isocyanate, “plays an essential role in the formation of proteins, which are basic ingredients for life,” said Victor Rivilla, a scientist at the Astrophysics Observatory in Florence, Italy, and co-author of a study published in Monthly Notices of the Royal Astronomical Society.

The findings could offer clues on how chemicals sparked into living matter on Earth several billion years ago.

At the very least, they show that elements crucial for the emergence of life “were very likely already available at the earliest stage of solar system formation,” said Niels Ligterink, a researcher at Leiden Observatory in the Netherlands and lead author of a second study in the same journal. [Continue reading…]

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Trump’s reneging on Paris climate deal turns the U.S. into a rogue state

Joseph Stiglitz writes: Donald Trump has thrown a hand grenade into the global economic architecture that was so painstakingly constructed in the years after the end of the second world war. The attempted destruction of this rules-based system of global governance – now manifested in Trump’s withdrawal of the United States from the 2015 Paris climate agreement – is just the latest aspect of the US president’s assault on our basic system of values and institutions.

The world is only slowly coming fully to terms with the malevolence of the Trump administration’s agenda. He and his cronies have attacked the US press – a vital institution for preserving Americans’ freedoms, rights and democracy – as an “enemy of the people”. They have attempted to undermine the foundations of our knowledge and beliefs – our epistemology – by labelling as “fake” anything that challenges their aims and arguments, even rejecting science itself. Trump’s sham justifications for spurning the Paris climate agreement is only the most recent evidence of this.

For millennia before the middle of the 18th century, standards of living stagnated. It was the Enlightenment, with its embrace of reasoned discourse and scientific inquiry, that underpinned the enormous increases in standards of living in the subsequent two and a half centuries.

With the Enlightenment also came a commitment to discover and address our prejudices. As the idea of human equality – and its corollary, basic individual rights for all – quickly spread, societies began struggling to eliminate discrimination on the basis of race, gender, and, eventually, other aspects of human identity, including disability and sexual orientation.

Trump seeks to reverse all of that. His rejection of science, in particular climate science, threatens technological progress. And his bigotry toward women, Hispanics, and Muslims (except those, like the rulers of Gulf oil sheikhdoms, from whom he and his family can profit), threatens the functioning of American society and its economy, by undermining people’s trust that the system is fair to all.

As a populist, Trump has exploited the justifiable economic discontent that has become so widespread in recent years, as many Americans have become downwardly mobile amid soaring inequality. But his true objective – to enrich himself and other gilded rent-seekers at the expense of those who supported him – is revealed by his tax and health-care plans. [Continue reading…]

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