Astronomy – September 2019

Water-rock reactions Hydrothermal vents Surface jets

Ice

shell

Ocean

Rocky

core

Ice-coated particles

South polar region

Brittle ice

Ductile ice

Cracks filled

with salt water

Hotspots

on seafloor

Hydrothermal circulation

(^3). (^1) mi
( 5 les
km)
(^40). (^4) m
( 6 iles
(^5) km)
POWERING THE GEYSERS
THE CASSINI SPACECRAFT detected hydrogen in the plume of gas and
icy material spraying from Enceladus during its final, deepest dive through the
plume October 28, 2015. By studying the plumes, researchers hope to determine
the composition of this moon’s subsurface ocean. This graphic illustrates a theory
on how water interacts with rock at the bottom of the ocean, producing hydrogen.
NASA/JPL-CALTECH/SOUTHWEST RESEARCH INSTITUTE