|When:||Friday, February 8, 2013, 10:30 a.m. to 11:30 a.m.
Join us for coffee beginning at 10:00 a.m.
|Where:||Seminar Conference Room, 10100 Burnet Road, Bldg 196-ROC, Austin, Texas 78758|
|Host:||Don Blankenship, UTIG|
Click for a Live Broadcast.
In the past few decades the debate about habitability of Europa has been focused strongly on the thickness of its ice shell. However an arguably more critical question is: how does the ice shell really work? Even now, ten years after the end of Galileo and without the ability yet to see below Europa's icy surface, there is still progress to be made by studying its surface. And in particular, we are just scratching the surface of what we can learn from terrestrial analogs.
Galileo-era analyses indicated that Europa has undergone geologically recent resurfacing, and implied that near-surface water was likely involved. However the amount of water and the details surrounding its interaction with the surface were not well constrained. We address this question with a new approach: we use process analogs from Earth's cryosphere-subglacial hydraulics, hydrofracture and brine infiltration-to gain insight into the behavior of dynamic water-ice interactions. With these as a foundation, our reanalysis of the morphology of Europa's enigmatic "chaos terrains" indicates that chaos features form in the presence of a great deal of liquid water, above large lenses trapped within 3km of Europa's surface. The detection of shallow subsurface "lakes" implies that Europa is currently active, and that rapid ice shell recycling could form the downward component of a conveyor belt between the ice and ocean. Hydrologic modeling suggests that material is also transferred horizontally through the upper ice shell.
The upward component of the conveyor belt whereby ocean material could be delivered to the near surface will be mediated by ice-ocean exchange. Here, terrestrial processes such as accretion, melt and redistribution will form the foundation of our understanding of ice-ocean interactions on Europa. And while microbial life within ice and below glaciers has been studied for decades, the ice-ocean interface has remained largely unexplored... until now. Project SIMPLE (Sub-Ice Marine and Planetary analog Ecosystems) is an extensive three-platform assault on the McMurdo Ice Shelf to characterize the environment at the ice-ocean interface and processes within the shelf, where the geophysical evolution of the ice will be coupled to its habitability. The results from SIMPLE will provide a basis for characterizing habitats and interactions between the ocean and the ice shelf via remote sensing and in situ analyses, revolutionizing our understanding of ice-ocean dynamics and ecosystems on both Earth and Europa.
While we wait for the opportunity to send a new mission to Europa, looking to our own cosmic backyard, Antarctica, provides a solid foundation for understanding Europa's dynamics and habitability and affords us the opportunity to develop techniques to explore this ice covered world not so unlike our own.