Dec 6, 2017

The secrets hiding under Europa's ice

Jupiter's icy moon Europa. Photo: NASA / JPL-Caltech / SETI Institute

Europa, the second moon of Jupiter, is encased in a thick crust of ice. Sitting far from the Sun, it's one of the last places you would expect to harbor life. But due to its elliptical orbit around Jupiter — it periodically swings closer and further from the giant planet — the differences in gravity flex and squeeze the core, heating it to molten temperatures.

The end result: Buried under 100 kilometers of rock-hard ice is a globe-spanning liquid water ocean. More liquid water than on the Earth. But is there life?

Why it matters: New simulations suggest the icy shell is broken into segments that shift, flex, and subduct, just like the Earth's crust. Essential nutrients on the surface could then make their way to the ocean, providing a possible pathway for life —permanently locked away from sunlight — to survive.

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Coronavirus spreads to more countries, and South Korea ups its case count

Data: The Center for Systems Science and Engineering at Johns Hopkins, the CDC, and China's Health Ministry. Note: China numbers are for the mainland only and U.S. numbers include repatriated citizens.

The novel coronavirus continues to spread to more nations, and the U.S. reports a doubling of its confirmed cases to 34 — while noting those are mostly due to repatriated citizens, emphasizing there's no "community spread" yet in the U.S. South Korea's confirmed cases jumped from 204 on Friday to 433 on Saturday.

The big picture: COVID-19 has now killed at least 2,362 people and infected more than 77,000 others, mostly in mainland China. New countries to announce infections recently include Israel, Lebanon and Iran.

Go deeperArrowUpdated 14 mins ago - Health

Centrist Democrats beseech 2020 candidates: "Stand up to Bernie" or Trump wins

Bernie Sanders rallies in Las Vegas, Nevada on Feb. 21. Photo: Mario Tama/Getty Images

Center-left think tank Third Way urgently called on the Democratic front-runners of the 2020 presidential election to challenge Sen. Bernie Sanders on the South Carolina debate stage on Feb. 25, in a memo provided to Axios' Mike Allen on Saturday.

What they're saying: "At the Las Vegas debate ... you declined to really challenge Senator Sanders. If you repeat this strategy at the South Carolina debate this week, you could hand the nomination to Sanders, likely dooming the Democratic Party — and the nation — to Trump and sweeping down-ballot Republican victories in November."

Situational awareness

Warren Buffett. Photo: Daniel Zuchnik/WireImage

Catch up on today's biggest news:

  1. Warren Buffett releases annual letter, reassures investors about future of Berkshire Hathaway
  2. Greyhound bars immigration sweeps
  3. U.S. military officially stops offensive operations in Afghanistan
  4. America's future looks a lot like Nevada
  5. Centrist Democrats beseech 2020 candidates: "Stand up to Bernie" or Trump wins