Scientists find strong evidence of 'ocean of water' on Saturn moon
7 July Daily Telegraph
Nasa's Cassini spacecraft has found strong evidence for an ocean of
water beneath the frozen crust of Saturn's largest moon Titan,
scientists said on Thursday.
The finding propels Titan into a shortlist of places including
Jupiter's moon Europa and Saturn's smaller moon Enceladus suspected of
harbouring underground seas. "The evidence is strong that Titan is
squishy," said planetary scientist Jonathan Lunine, with Cornell
University.
The evidence was put together during six passes over Titan by Cassini,
which is orbiting Saturn, between 2004 and 2011.
During the fly-bys, scientists measured minute changes in the pitch
of radio signals passing between the spacecraft and Earth to figure how
much Saturn's gravity deformed the moon.
They then turned to computer models to match a 10-meter (33-foot)
distortion with possible scenarios to explain what was going on. The
more solid the moon's interior, the less it would be impacted by
Saturn's gravity.
"The measurement is pretty conclusive about the existence of an
internal ocean," said lead researcher Luciano Iess, with Sapienza
University in Rome, Italy.
"The presence of water does not imply life," he added. "“But Titan
has many interesting ingredients hydrocarbons, a hydrological cycle and
a thick atmosphere."Scientists have no idea if the ocean is in contact
with rock, a possible source of minerals and other components believed
to be needed for life.
Based on the Cassini findings, Titan's suspected ocean lies about 100
kilometres (62 miles) beneath the surface.Although the moon sports lakes
of liquid hydrocarbons, such as methane and ethane, Titan's ocean is
probably mostly water." |