The processes occurring at the ice-ocean interface of icy satellites provides chemical and physical gradients that are conducive for known metabolic processes of life.

The available nutrients and energy at ice-ocean interfaces (sea ice or ice shelves) provide habitable niches for life on earth, and similar processes that make that possible could occur in icy satellites.
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The processes occurring at the ocean-seafloor, or within the ocean, of ice satellites are conducive for known metabolic processes of life.

Earth's ocean floor has many habitable niches. The process that create the energy and chemistry that make them habitable may occur at the ocean-seafloor of icy satellites.
Created at: 
2020-04-17
  Updated at: 
2020-04-20
Curator:
Chase Chivers   Subscribe ...

Background

Analog Environments

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Sympagic organisms at ice-ocean interfaces are important part of the marine ecosystems of the polar regions.

eOrganisms living internally in sea ice or at the ice-water interface provide a substantial part of the total primary production of the polar regions.

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Hydrothermal vents at the seafloor of Earth’s ocean host vast macrofaunal, microbial, and bacterial communities

eAt the serpentinite-hosted Lost City hydrothermal field, a microbial and macrofaunal communities excel in an ecosystem in which geological, chemical, and biologically processes are intimately linked.

eOwing to the water-rock reactions that provide an abundance of redox reactions, seafloor hydrothermal vents support diverse ecosystems with enormous biomass and productivity compared with elsewhere in the deep oceans.

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Microbial life can thrive in highly saline and low temperature ice-water environments.

eA phylogenetically diverse and metabolically active microbial community can thrive in extreme terrestrial cryogenic brine systems of a perennially ice-covered Antarctic lake.

Icy Ocean World Environments

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Radiolytic products delivered from Europa’s surface to the ocean provide nutrients for life at the ice-ocean interface.

eA putative microbial community could be driven by the delivery of oxidants and organics from the surface to subsurface water.

ePutative microbial mats may concentrate around oxidant-rich ice-shell sites at the ice-water interface of irradiated ice shells.

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Water-rock reactions at the ocean floor of icy ocean worlds provide the necessary energy and chemistry for life.

eSerpentinization reactions in cracks in the rocky mantle may drive hydrothermal activity that could provide Europa’s and Enceladus’ seafloor heat fluxes on the same order as present-day radiogenic heat at Earth’s surface.

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The ice-ocean interface of icy worlds provides rich chemical gradients for putative ecosystems.

eBrine driven chemical gardens at the ice-ocean interface may exist on icy ocean worlds, which constitute ideal places where ecosystems of organisms might be found.

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The chemistry detected in the ocean water-derived plumes of Enceladus indicates methanogenesis may be occurring at the ocean floor.

eAn abundance of molecular hydrogen detected in the subsurface global-ocean derived plumes on Enceladus signals a thermodynamic disequilibrium that hints at the possibility of methanogenesis at the seafloor.

eThe estimated molecular hydrogen production at Enceladus’ ocean floor may be high enough to support methanogenic life.