Updated Feb 28, 2018

Earth bacteria could survive on one of Saturn's moons

Saltwater geysers erupt from Enceladus' icy surface. Credit: NASA/JPL/SSI

Bacterial life could survive in the ocean beneath the surface of one of Saturn’s icy moons, according to new research published Tuesday in the journal Nature Communications.

Why it matters: The Saturnian moon Enceladus is considered one of the best possible places to look for life in our solar system — and our galaxy — so far. If we were to find life on Enceladus, it would also broaden the types of places we could search for life. Right now, we just look for Earth-like planets close enough to the sun to have liquid water.

The background: NASA’s spacecraft Cassini flew by Enceladus and spotted icy geysers erupting from the planet’s surface, indicating a liquid ocean beneath the ice sheets and possible hydrothermal activity. It flew through the geysers, and detected carbon, hydrogen, and crucially methane, in the plumes. That’s a big deal because certain types of bacterial life can produce methane.

What they did: Study author Simon Rittman ran a number of simulations to see if Methanermococcus okinawensi, a methane-producing microbe that lives on hydrothermal vents, could survive in an environment like on Enceladus. They altered the acidity and chemical composition of the environment, changed the pressure, and changed temperatures. Since no one knows exactly what the world is like beneath Enceladus’ ice sheets, they had to approximate.

What they found: The bacteria survived almost everything they threw at it, including low levels of formaldehyde, which were detected on the moon. But high levels killed the bacteria.

Yes, but the methane on Enceladus could have come from natural processes, and doesn’t need bacteria to be explained. It's also unknown if the hydrothermal vents Methanermococcus needs to survive are present on the planet — it’s just a guess.

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Judge rules against Trump policy limiting public comment on energy leasing

Photo: Joe Amon/The Denver Post via Getty Images

A federal judge on Thursday overturned a 2018 Trump administration directive that sought to speed up energy leases on public land by limiting the amount of time the public could comment.

Why it matters: U.S. Chief Magistrate Judge Ronald Bush's decision voids almost a million acres of leases in the West, according to The Washington Post. It's a victory for environmentalists, who tried to block the change as part of an effort to protect the habitat of the at-risk greater sage grouse.

  • The ruling invalidated five oil and gas leases in Nevada, Utah, and Wyoming, and affected 104,688 square miles of greater sage-grouse habitat, per The Associated Press.
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The big picture: From Axios' Amy Harder, this is the latest in a long and convoluted list of regulatory rollbacks the Trump administration is pursuing on environmental rules that courts are, more often than not, rebutting. With Congress gridlocked on these matters, expect the courts to be the default way Trump's agenda faces checks (unless, of course, a Democrat wins the White House this November).

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Washing your hands is the best way to protect against the novel coronavirus, according to doctors and health officials, as the virus continues to spread around the globe.

Why it matters: Frequent hand washing can stop germs from spreading in a community, a known preventative for COVID-19 and influenza.

Major League Soccer embarks on its 25th season

Illustration: Aïda Amer/Axios

As Major League Soccer begins its 25th season, the league is financially stable and surging in popularity, and its 26 teams have gorgeous facilities and rapidly increasing valuations.

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