Water pockets on Europa bode well for the search for extraterrestrial life
Through analyzes of surface elevation and ice-penetrating radar data collected from 2015 to 2017 by NASA’s Operation IceBridge, researchers have revealed how Northwestern Greenland’s Double Ridge came about. when the ice fractured around a pocket of pressurized liquid water that was refreezing inside the ice sheet, causing two peaks to rise in the distinct shape.
“In Greenland, this double ridge formed where water from surface lakes and streams frequently flows to the surface and freezes again,” said study lead author Riley. Culberg, a graduate student in electrical engineering at Stanford. “One way that similar shallow pockets of water could form on Europa could be that water from the subterranean ocean is forced into the ice shell by fractures – and this would suggest that there could be an amount reasonable exchanges inside the ice shell.”
Rather than behaving like an inert block of ice, Europa’s shell appears to undergo a variety of geological and hydrological processes – an idea supported by this study and others, including water plume proof which burst to the surface. A dynamic ice shell supports habitability as it facilitates the exchange between the subterranean ocean and nutrients from nearby celestial bodies accumulated on the surface.
“People have been studying these double ridges for over 20 years now, but this is the first time we’ve been able to observe something similar on Earth and see nature working its magic,” the co-author said. study, Gregor Steinbrügge, a planetary scientist. at NASA’s Jet Propulsion Laboratory (JPL) who began work on the project as a postdoctoral researcher at Stanford. “We are taking a much bigger step in the direction of understanding the processes that really dominate the physics and dynamics of the ice shell of Europa.”
The co-authors said their explanation of how the shape of the double ridges is so complex that they could not have devised it without the analogue on Earth.
“The mechanism we propose in this paper would have been almost too bold and complicated to propose without seeing it happen in Greenland,” Schroeder said.
The results equip researchers with a radar signature to quickly detect this process of double ridge formation using ice-penetrating radar, which is among the instruments currently planned to explore Europa from space.
“We’re another hypothesis on top of many – we just have the advantage that our hypothesis has a few observations of a similar feature forming on Earth to back it up,” Culberg said. “It opens up all these new possibilities for a very exciting discovery.”
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Schroeder is also a faculty member of the Human-Centered Artificial Intelligence (HAI) Instituteassociate professor, by courtesy, of electrical engineering and center scholar, by courtesy, at the Stanford Woods Institute for the Environment.
This research was supported by a National Defense Science and Engineering Graduate Fellowship and, in part, NASA grant NNX16AJ95G and NSF grant 1745137.
Riley Culberg, School of Engineering: [email protected]
Dustin Schroeder, School of Earth, Energy and Environmental Sciences: (650) 725-7861, (440) 567-8343 (mobile); [email protected]
Danielle Torrent Tucker, School of Earth, Energy and Environmental Sciences: (650) 497-9541; [email protected]