Explanation:
Investigators suspect
the domed feature detailed
above is an ice volcano, or cryovolcano,
seen
in infrared light through the hazy atmosphere on
Saturn's moon Titan.
Since Titan's surface temperature is around -180 degrees
Celsius, 'lava' welling up to form the
volcanic
mound would be icy indeed - possibly a slurry of
methane, ammonia, and water ice combined with other ices
and hydrocarbons.
The circular
feature is roughly thirty kilometers in
diameter.
If its volcanic nature is confirmed, the discovery of
cryovolcanism on Titan could explain the origin of methane
in Titan's atmosphere.
Before the Cassini-Huygens mission to Saturn,
a popular explanation for replenishing Titan's
concentration of atmospheric methane
was the presence of an extensive, methane-rich,
hydrocarbon sea.
But Cassini's instruments and the
Huygens surface probe
have failed to find such a global ocean.