Scientists may have solved the mystery behind one of the five mass extinctions in Earth's history – a time 65 million years ago at the end of the Cretaceous period when a meteor struck the Earth and wiped out dinosaurs and nearly every living creature on the planet. The reason? A blanket of soot cast the Earth into darkness for up to two years, according to a new study.

What they found: Using a sophisticated climate supercomputer, researchers modeled what may have happened when a meteor hit the planet and found such an impact would likely create raging global wildfires and toss a blanket of soot into the atmosphere, thereby keeping more than 99% of sunlight from reaching the surface of the Earth for up to two years.

Why did the dinosaurs die?

  • With the Earth in darkness for that long, photosynthesis would stop; temperatures would plummet by more than 30 degrees Fahrenheit for several years; and the protective ozone layer would be depleted.
  • This creates a deadly combination that the researchers say could have led to mass extinctions and the end of the dinosaurs.
  • Geological evidence shows that the Cretaceous mass extinction event occurred at the same time that a very large asteroid hit Earth in what is now the Yucatan Peninsula.
  • What the new computer model shows is how such a collision would trigger other events in its wake that drastically altered Earth's climate.

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Updated 26 mins ago - Politics & Policy

Coronavirus dashboard

Illustration: Eniola Odetunde/Axios

  1. Global: Total confirmed cases as of 9 a.m. ET: 19,128,901 — Total deaths: 715,555— Total recoveries — 11,591,028Map.
  2. U.S.: Total confirmed cases as of 9 a.m. ET: 4,884,406 — Total deaths: 160,111 — Total recoveries: 1,598,624 — Total tests: 59,652,675Map.
  3. Politics: Trump floats executive action even if stimulus deal is reached.
  4. Business: U.S. economy adds 1.8 million jobs in July — Household debt and credit delinquencies dropped in Q2.
  5. Sports: The pandemic's impact on how sports are played.
  6. 1 🎮 thing: Video gaming growth soars.

Trump floats executive action even if stimulus deal is reached

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The White House is finalizing a series of executive orders addressing key coronavirus stimulus priorities if negotiations with Congress fall apart, and it's leaving the door open for President Trump to use them even if a deal is reached that doesn't encompass all of his priorities, two administration officials tell Axios.

What we’re hearing: “I wouldn't be surprised that, if something gets left off the table, we’d be like ‘we can take this executive action too and be able to win on it anyway,’” one official said.

48 mins ago - Technology

TikTok responds to Trump executive order: "We are shocked"

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TikTok said Friday that it was "shocked" by President Trump's executive order that will ban Americans from dealing with ByteDance, its China-based owner, in 45 days.

Why it matters: TikTok argued that Trump's move "risks undermining global businesses' trust in the United States' commitment to the rule of law, which has served as a magnet for investment and spurred decades of American economic growth."