New high-resolution photos of Jupiter’s icy moon Europa show the surface is covered with something akin to highways rather than craters, and they go on for miles.
Europa is believed to be the most likely spot in the solar system to find life outside of Earth — but it would be aquatic, not land-dwelling.
NASA’s Juno mission captured the photos Sept. 29 during a rare flyby that got within about 256 miles of the surface, and scientists admit one photo “of the moon’s heavily fractured icy crust” is puzzling.
“The image covers about 93 miles (150 kilometers) by 125 miles (200 kilometers) of Europa’s surface, revealing a region crisscrossed with a network of fine grooves and double ridges (pairs of long parallel lines indicating elevated features in the ice),” NASA says.
“Near the upper right of the image, as well as just to the right and below center, are dark stains possibly linked to something from below erupting onto the surface.”
Social media commenters immediately began offering theories, with some calling the lines a road map of highways, others suggesting they’re tracks left by something sliding across the ice, and a few pointing out they saw pentagrams in the photo.
NASA scientists have theories, too. They suspect the lines are spots where Europa’s surface “has pulled apart” and something dark “from beneath the surface” has filled in the crack.
“Many believe cracks and ridges on/in the ice shell marking weak lines within the moon’s ice crust,” according to Scott Bolton, principal investigator for the Juno mission.
The cracks are “emphasized and exacerbated by the swelling and falling of tides due to Jupiter’s gravitational pull,” he said.
Europa is believed to be circled by “a huge, salty, liquid ocean” topped with a 15-mile thick crust of ice. Temperatures range from minus 210 degrees Fahrenheit to minus 370 degrees at the poles, NASA says.
However, deep sea exploration on Earth has proven that life can be found at even the most extreme locations on Earth. Scientists speculate it may also be true elsewhere in the solar system.
“This image is unlocking an incredible level of detail in a region not previously imaged at such resolution and under such revealing illumination conditions,” said Heidi Becker, lead co-investigator for Juno’s Stellar Reference Unit.
“These features are so intriguing. Understanding how they formed – and how they connect to Europa’s history – informs us about internal and external processes shaping the icy crust.”
“In the early 2030s, the NASA’s Europa Clipper spacecraft will arrive and strive to answer these questions about Europa’s habitability. The data from the Juno flyby provides a preview of what that mission will reveal,” NASA says.