Jan 12, 2019

Our sun will turn into a solid crystal in 10 billion years

In about 10 billion years, our sun is likely to turn into a white dwarf — a shrunken, extremely dense star whose nuclear core has burned out and gotten rid of its outer layers.

A new study published Wednesday in the journal Nature claims to reveal the first evidence that white dwarf stars form solid, crystal cores containing metallic oxygen and carbon. The oldest white dwarfs, the study finds, are likely to be almost fully comprised of crystals.

Why it matters: The process of crystallization, similar to water turning into ice but occurring at far higher temperatures (about 10 million degrees Celsius), slows the cooling of these stars, potentially making them billions of years older than originally thought. Scientists use white dwarfs as markers of time in order to get a better idea of the age of surrounding stars and planets.

What they did: Astronomers from the University of Warwick in the U.K. used observations from the European Space Agency's Gaia satellite to examine the luminosities and colors from about 15,000 white dwarf candidates within about 300 light-years of Earth.

  • They found a large number of stars that had colors and luminosities that seemed to match the phase in a star's development when it's releasing huge amounts of latent heat, which results in a slower cooling process.
  • According to a press release, such stars may have slowed their aging by as many as 2 billion years.
"This means that billions of white dwarfs in our galaxy have already completed the process and are essentially crystal spheres in the sky."
— Study lead author, astronomer Pier-Emmanuel Tremblay, in a statement

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Coronavirus dashboard

Illustration: Sarah Grillo/Axios

  1. Global: Total confirmed cases as of 3 p.m. ET: 5,931,112 — Total deaths: 357,929 — Total recoveries — 2,388,172Map.
  2. U.S.: Total confirmed cases as of 3 p.m. ET: 1,711,313 — Total deaths: 101,129 — Total recoveries: 391,508 — Total tested: 15,192,481Map.
  3. States: New York to allow private businesses to deny entry to customers without masks.
  4. Public health: Louisiana Sen. Cassidy wants more frequent testing of nursing home workers.
  5. Congress: Pelosi slams McConnell on stimulus delay — Sen. Tim Kaine and wife test positive for coronavirus antibodies.
  6. Tech: Twitter fact-checks Chinese official's claims that coronavirus originated in U.S.
  7. What should I do? When you can be around others after contracting the coronavirus — Traveling, asthma, dishes, disinfectants and being contagiousMasks, lending books and self-isolatingExercise, laundry, what counts as soap — Pets, moving and personal healthAnswers about the virus from Axios expertsWhat to know about social distancingHow to minimize your risk.
  8. Other resources: CDC on how to avoid the virus, what to do if you get it, the right mask to wear.

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Updated 25 mins ago - Politics & Policy

Twitter fact-checks Chinese official's claims that coronavirus originated in U.S.

Chinese Foreign Ministry spokesman Zhao Lijian. Photo: Greg Baker/AFP via Getty Images

Twitter slapped a fact-check label on a pair of months-old tweets from a Chinese government spokesperson that falsely suggested that the coronavirus originated in the U.S. and was brought to Wuhan by the U.S. military, directing users to "get the facts about COVID-19."

Why it matters: The labels were added after criticism that Twitter had fact-checked tweets from President Trump about mail-in voting, but not other false claims from Chinese Communist Party officials and other U.S. adversaries.

Podcast: Trump vs. Twitter, round two

President Trump is escalating his response to Twitter’s fact check of his recent tweets about mail-in voting, issuing an executive order that's designed to begin limiting social media's liability protections. Dan digs in with Axios' Margaret Harding McGill.

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