In a new research, a scientist has suggested that at least three million tons of fishlike creatures could theoretically live and breathe under Jupiter’s moon Europa’s global ocean.
The scientist in question is Richard Greenberg of the University of Arizona in Tucson.
Below its icy crust, Europa is believed to host a global ocean up to a hundred miles (160 kilometers) deep, with no land to speak of at the surface.
The extraterrestrial ocean is currently being fed more than a hundred times more oxygen than previous models had suggested, according to provocative new research.
That amount of oxygen would be enough to support more than just microscopic life-forms, and at least three million tons of fishlike creatures could theoretically live and breathe on Europa, according to Greenberg.
“There’s nothing saying there is life there now,” said Greenberg, who presented his work last month at a meeting of the American Astronomical Society’s Division for Planetary Sciences. “But we do know there are the physical conditions to support it,” he added.
“In fact, based on what we know about the Jovian moon, parts of Europa’s seafloor should greatly resemble the environments around Earth’s deep-ocean hydrothermal vents,” said deep-sea molecular ecologist Timothy Shank.
“I’d be shocked if no life existed on Europa,” said Shank.
Europa’s smooth surface is marred only by dark, crisscrossing ridges that suggest the icy shell is being stretched and compressed by tidal forces.
“We’re used to thinking of tides on Earth as something seen on the shore,” Greenberg explained.
But, on a larger scale, gravity from the sun and moon constantly squishes and stretches Earth as a whole.
Europa, which is about as big as our moon, also gets tidally stretched, not by the sun, but by the gravity of massive Jupiter.
“The friction from all this tidal stretching probably heats Europa enough to maintain liquid water,” Greenberg said.
The warmer ocean material may be oozing up through cracks in the ice and freezing on the surface at the same rate that older ice sinks and melts into the liquid interior.
This cycle of “repaving” would explain the young look of the surface ice—and would open the door for oxygen at the surface to permeate the subsurface ocean.
Greenberg’s generous estimate of oxygen in Europa’s ocean—and the resulting speculation that fishlike creatures may exist there—depends on the surface repaving to have happened at a relatively stable rate, in this case, a complete renewal every 50 million years.