Oceans Under Jupiters Callisto
Explanation:
Why does
Jupiter's moon
Callisto alter the
magnetic field of Jupiter in its vicinity?
Callisto itself does not have a strong magnetic field.
One possible answer is that
Callisto harbors sub-surface oceans of
electrically conducting salt-water.
This hypothesis was
bolstered recently by a new analysis of how
Callisto creates and dissipates heat.
Callisto is thought to create heat by the
radioactive decay of internal rock -- a process that keeps the
Earth's mantle molten.
Callisto may not be able to dissipate this heat very efficiently,
however, as it has thick layers of ice and rock on its surface.
Perhaps this heat is enough to keep sub-surface water from
freezing into ice.
With
this hypothesis, Callisto joins two other of
Jupiter's moons,
Europa and
Ganymede,
in candidates for sub-surface oceans.
Callisto's oceans, however,
might prove too hostile to support
Earth-like life.
Authors & editors:
Robert Nemiroff
(MTU) &
Jerry Bonnell
(USRA)
NASA Web Site Statements, Warnings,
and Disclaimers
NASA Official: Jay Norris.
Specific
rights apply.
A service of:
LHEA at
NASA /
GSFC
& Michigan Tech. U.
