Erin Ross Feb 28
SaveSave story

Earth bacteria could survive on one of Saturn's moons

Geysers erupt from the pole of Saturn's moon Enceladus.
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.

Steve LeVine 14 hours ago
SaveSave story

The stakes for who wins the AI race

A sentient computer saying 'Hello World' in English, Chinese and Russian.
Illustration: Lazaro Gamio/Axios

One of the most urgent themes in technology is the global rivalry for dominance of the evolving sector of artificial intelligence — geopolitical and economic supremacy is said to be at stake. Experts view the U.S. and China as the top contenders, but other nations, including Russia, are working on AI, too.

What it means: In its latest edition, the Economist draws a sharp line as to the extraordinary ramifications of the race. "The global spread of a technosystem conceived in, and to an unknown extent controlled by, an undemocratic, authoritarian regime could have unprecedented historical significance," the magazine wrote.

SaveSave story

Airlines may not be the "germ incubator" you thought

Inside of an airplane
Photo: via Getty Images

The chance of becoming infected with a common respiratory virus on an airplane may be smaller than originally thought — less than 3% unless you are sitting within one meter of an infected person, where your chances rise to 80%, according to a study published in PNAS Monday.

Why it matters: There are more than 3 billion airline passengers annually, and global health officials want to learn more how infectious diseases are transmitted, particularly after reported transmission of cases of flu pandemic and severe acute respiratory syndrome (SARS) via planes.