And that could be a good thing. [Image credit: Nasa/JPL. Image reprocessed by Ted Stryk]. As a BBC report notes, Nasa scientists have published their latest thinking on the chaos terrains of Jovian satellite Europa. [All hail our friend and lord, Jupiter! - Ed] *ahem*. It suggests that the “chaos terrains form above liquid water lenses perched within the ice shell as shallow as 3 kilometres”.
Here’s a cross-section view through the surface of Europa showing the suspected “Great Lake.” [Image credit: Britney Schmidt/Dead Pixel VFX/Univ. of Texas at Austin.]
And such relatively shallow subsurface water “could make Europa and its ocean more habitable.” From the JPL/Nasa press release
NASA’s Galileo spacecraft, launched by the space shuttle Atlantis in 1989 to Jupiter, produced numerous discoveries and provided scientists decades of data to analyze. Galileo studied Jupiter, which is the most massive planet in our solar system, and some of its many moons.
One of the most significant discoveries was the inference of a global saltwater ocean below the surface of Europa. This ocean is deep enough to cover the whole surface of Europa and contains more liquid water than all of Earth’s oceans combined. However, being far from the sun, the ocean surface is completely frozen. Most scientists think this ice crust is tens of miles thick.
“One opinion in the scientific community has been if the ice shell is thick, that’s bad for biology. That might mean the surface isn’t communicating with the underlying ocean,” said Britney Schmidt, lead author of the paper and postdoctoral fellow at the Institute for Geophysics, University of Texas at Austin. “Now, we see evidence that it’s a thick ice shell that can mix vigorously and new evidence for giant shallow lakes. That could make Europa and its ocean more habitable.”
As the University of Texas at Austin press release adds
The water could represent a potential habitat for life, and many more such lakes might exist throughout the shallow regions of Europa’s shell, lead author Britney Schmidt, a postdoctoral fellow at The University of Texas at Austin’s Institute for Geophysics, writes in the journal Nature.
Further increasing the potential for life, the newly discovered lake is covered by floating ice shelves that seem to be collapsing, providing a mechanism for transferring nutrients and energy between the surface and a vast ocean already inferred to exist below the thick ice shell.
Here are the Nasa scientists presenting their findings at a press conference yesterday.