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Blast from the past: comet may have hit Earth 56 million years ago

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Droplets of glass dug up in New Jersey and from the Atlantic seabed indicate a comet or some other extraterrestrial object may have smacked Earth 56 million years ago, roughly 10 million years after the asteroid impact that doomed the dinosaurs.

Scientists said on Thursday the collision may have triggered a particularly warm, ice-free period on Earth when important mammalian groups, including the primate lineage that led to humans, appeared for the first time.

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The findings, published in the journal Science, marked the latest evidence of the profound influence that past impacts by celestial bodies have had on life on Earth.

The tiny spherical bits of dark glass, called microtektites, represent strong evidence of a collision with a comet or asteroid, the researchers said. They form when a space rock hits Earth’s surface and vaporizes the spot where it lands, ejecting into the air bits of molten rock that solidify into glass.

The microtektites were excavated from a geological layer marking the start of the Eocene Epoch about 56 million years ago from three sites in southern New Jersey (Millville, Wilson Lake and Medford) and an underwater site east of Florida.

That coincided with the beginning of a warming event, called the Paleocene-Eocene Thermal Maximum, associated with an accumulation of atmospheric carbon dioxide. It lasted more than 100,000 years and drove up global temperatures about 9-14 degrees Fahrenheit (5-8 degrees Celsius).

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The impact of an asteroid about six miles wide (10 km) off Mexico’s Yucatan Peninsula 10 million years earlier killed off many marine and terrestrial creatures including the dinosaurs and enabled mammals to gain supremacy.

No such mass extinction was associated with the event 56 million years ago, although many single-celled ocean-bottom creatures disappeared. During the warming period, primates and two mammal groups — one that includes deer, antelope, sheep and goats and another that includes horses and rhinos — first appear in the fossil record.

The researchers said they have not found the location of an impact crater linked to the collision. They said geological evidence suggested the object was a comet.

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“We can’t really say where it was, or how big, at this point,” said geochemist Morgan Schaller of Rensselaer Polytechnic Institute, who led the study.

While the findings are not proof that the impact caused the warming period, they are “a rather dramatic finding in support of an impact trigger” for the climate changes, said planetary scientist Dennis Kent of Columbia University’s Lamont-Doherty Earth Observatory and Rutgers University.

(Reporting by Will Dunham; Editing by Sandra Maler)

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… then let us make a small request. Like you, we here at Raw Story believe in the power of progressive journalism — and we’re investing in investigative reporting as other publications give it the ax. Raw Story readers power David Cay Johnston’s DCReport, which we've expanded to keep watch in Washington. We’ve exposed billionaire tax evasion and uncovered White House efforts to poison our water. We’ve revealed financial scams that prey on veterans, and efforts to harm workers exploited by abusive bosses. We’ve launched a weekly podcast, “We’ve Got Issues,” focused on issues, not tweets. Unlike other news sites, we’ve decided to make our original content free. But we need your support to do what we do.

Raw Story is independent. You won’t find mainstream media bias here. We’re not part of a conglomerate, or a project of venture capital bros. From unflinching coverage of racism, to revealing efforts to erode our rights, Raw Story will continue to expose hypocrisy and harm. Unhinged from corporate overlords, we fight to ensure no one is forgotten.

We need your support to keep producing quality journalism and deepen our investigative reporting. Every reader contribution, whatever the amount, makes a tremendous difference. Invest with us in the future. Make a one-time contribution to Raw Story Investigates, or click here to become a subscriber. Thank you.



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Parents fight for custody of 4-year-old son after trying to treat his cancer with tea and ‘a positive state of mind’

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Two Florida parents are fighting this week to regain custody of their 4-year-old son who was taken away from them after they tried to treat his leukemia with a combination of tea and a "positive state of mind."

Local news station WFLA reports that Tampa Bay residents Joshua McAdams and Taylor Bland-Ball are headed to court to push for custody to be reinstated months after they decided to stop medical treatment for their 4-year-old son Noah.

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Trump slurs media as ‘fake and corrupt’ for disputing his claims about Elton John

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President Donald Trump hyped his claims about selling out a New Hampshire rally in a new attack on the news media.

The president insisted Monday that he enjoyed "massive overflow crowds" at his rally last week at SNHU Arena in Manchester, and slurred journalists as "fake and corrupt" for reporting the venue wasn't filled to capacity.

The Fake and Corrupt Media is sooo bad for our Country, The Enemy of the People! https://t.co/GPiklem0u1

— Donald J. Trump (@realDonaldTrump) August 20, 2019

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Watching clips from recent rallies in red states, it is obvious that President Donald Trump continues to be wildly popular among his hardcore far-right base. But that base is by no means representative of the United States on the whole. And journalist David A. Graham, in a report for The Atlantic, explains that not only is Trump failing to expand his base — he is, more and more, out of touch with public opinion.

“Recent polling shows that Donald Trump has managed to reshape American attitudes to a remarkable extent on a trio of his key issues: race, immigration and trade,” Graham observes. “There’s just one catch: the public is turning against Trump’s views.”

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