What’s in Europa’s ocean? Scientists say just scratch the surface

Using the Keck II telescope and OSIRIS spectrometer on a mountain in Mauna Kea, Hawaii, scientists from Caltech and NASA’s Jet Propulsion Laboratory have discovered what lies beneath the frozen surface of Jupiter’s moon Europa.

And apparently, it’s a compelling story.

Europa’s ocean looks a lot like ours, said Mike Brown, a scientist at Caltech who co-wrote a paper on the Jupiter satellite. Beneath a thick layer of ice (yes, the frozen-water kind) flows a massive ocean of salt water and other chemicals, which if stirred with geological activity and a sprinkle of energy, could harbor life, scientists believe.

Using the latest technology to analyze the reflection of sunlight off Europa’s surface, Brown and his colleagues were able to determine that some of the material they’ve been staring at for decades is salt that was carried up from the moon’s liquid underbelly.


“There’s evidence that the oceans are very much in composition like our oceans,” Brown said. “We know they’re nice places for life.”

Since NASA’s Galileo mission visited Europa and other parts of the solar system between 1989 and 2003, researchers have speculated that salt and other chemicals made their way to the surface but couldn’t confirm it. Brown likened it to seeing a fingerprint from a distance and being unable to decipher the unique swirls and loops every person has.

Today’s technology gave researchers their best image yet of the moon’s chemical fingerprint. There’s salt, sulfur and possibly even magnesium -- all chemicals found on Earth.

Outside of landing a microphone on the surface and listening for whales below, Brown joked, landing something on Europa for a soil sample is the best option.

“We have the technology to do it,” Brown said. “Europa just sticks out like a sore thumb, with this place with huge amounts of water.”

The Jupiter moon has more water than Earth, and possibly more than any other rock floating around our solar system, he said.

Then there’s the fact that not far away from it is Io, a volcanic Jupiter moon that continually spits sulfur into space, much of which slams into Europa’s surface at more than 156,000 mph.

“There’s your energy,” Brown said.

Leave that whole rule about not judging a book by its cover for Earth. When it comes to Jupiter’s watery moon, Europa, there’s no better way to learn the story.

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