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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Updated 35 mins ago - Politics & Policy

Coronavirus dashboard

Illustration: Sarah Grillo/Axios

  1. Global: Total confirmed cases as of 8:30 p.m. ET: 18,448,084 — Total deaths: 698,023 — Total recoveries — 11,048,174Map.
  2. U.S.: Total confirmed cases as of 8:30 p.m. ET: 4,765,170 — Total deaths: 156,668 — Total recoveries: 1,528,979 — Total tests: 57,543,852Map.
  3. States: New York City health commissioner resigns in protest of De Blasio's coronavirus response — Local governments go to war over schools.
  4. Public health: 59% of Americans support nationwide 2-week stay-at-home order in NPR poll.
  5. Politics: Trump's national security adviser returns to work after coronavirus recovery Republicans push to expand small business loan program.
  6. Sports: Indy 500 to be held without fansRafael Nadal opts out of U.S. Open.

Voters visit polls in Arizona, Kansas, Michigan, Missouri, Washington

Photo: Michael B. Thomas/Getty Images

Primary elections on Tuesday in fives states see crowded fields of both Republicans and Democrats hoping to make the ballot in 2020.

What to watch: Rep. Rashida Tlaib (D-Mich.) is "fighting for her political life" in a tight primary race against Detroit City Council President Brenda Jones, who Tlaib beat by 900 votes in 2018, The New York Times writes. Senate Republicans are also watching the primary race in Kansas to see who could replace retiring Republican Sen. Pat Roberts.

Updated 3 hours ago - World

At least 50 killed, 3,000 injured after massive explosion rocks Beirut

Photo: Anwar Amro/AFP via Getty Images

A major explosion has slammed central Beirut, Lebanon, damaging buildings as far as several miles away and injuring scores of people.

Driving the news: Lebanon's health minister said in televised remarks that more than 50 people have been killed and over 3,000 injured. Prime Minister Hassan Diab said the explosions occurred at a warehouse that had been storing 2,750 tons of ammonium nitrate for the past six years, per NBC.