From the ArcaMax Publishing, Science & Technology Newsletter:
http://www.arcamax.com/news/technology/s-570582-268699
PASADENA, Calif. (UPI) -- Scientists working on the U.S. space
agency's Cassini spacecraft's mission say Saturn's moon Enceladus
might have an underground ocean.
The researchers said they have, for the first time, detected sodium
salts in Saturn's outermost ring. That finding, they said, suggests
Enceladus, which primarily replenishes the ring with material from
discharging jets, could harbor a reservoir of liquid water -- perhaps
an ocean -- beneath its surface.
The Cassini spacecraft's instruments discovered the Enceladus
water-ice jets in 2005. Those jets expel tiny ice grains and vapor,
some of which escape the moon's gravity and form Saturn's outermost
ring. Cassini's cosmic dust analyzer examined the composition of the
ice grains and found salt within them.
"We believe that the salty minerals deep inside Enceladus washed out
from rock at the bottom of a liquid layer," said Frank Postberg,
Cassini scientist for the cosmic dust analyzer at the Max Planck
Institute for Nuclear Physics in Heidelberg, Germany.
Postberg and his colleagues conclude liquid water must be present
because it's the only way to dissolve the significant amounts of
minerals that would account for the levels of salt detected. The
process of sublimation, the mechanism by which vapor is released
directly from solid ice in the crust, cannot account for the presence
of salt.
The discovery is reported in the June 25 issue of the journal Nature.