GALILEAN MOONS ( PART - 3 )

 GANYMEDE :

In mythology, Ganymede was a beautiful young boy who was carried to Olympus by Zeus (the Greek equivalent of the Roman god Jupiter) disguised as an eagle. Ganymede became the cupbearer of the Olympian gods.

Ganymede has a radius of 1,635 miles (2,631 kilometers) and is the largest moon in our solar system. It’s bigger than Mercury and Pluto.

Magnetic field :

                      Ganymede's magnetic field was discovered by the Galileo mission in the mid-1990s. Although magnetic induction signatures were found for Europa, Ganymede, and Callisto, resulting from currents generated in salt-water oceans in these bodies, Ganymede was the sole Galilean satellite to demonstrate a self-sustained dynamo-generated field. There is little data available for the spectrum of the field aside from a dipole movement

Like Mercury, Ganymede's small size suggests that there must be a significant fraction of light elements such as sulfur in its core to keep it liquid in the present day. It is unknown whether Ganymede has a solid inner core, but the dynamo may have a compositional driving source if the liquid core is in a regime where it freezes at the outer boundary, releasing negatively buoyant iron-rich fluid, rather than freezing at the inner boundary like in the Earth's core. Dynamo studies including different buoyancy source distributions intended to mimic these solidification processes have been carried out.

Magnetosphere :

       The Galileo spacecraft, the first to orbit Jupiter, made the major discovery that Ganymede has its own magnetosphere – a region of charged particles that surrounds many planets but had never before been found around a moon. Galileo even captured sounds of whistling and static caused by Ganymede's magnetosphere.

FACTS :

Biggest Moon

Long days

Thin Atmosphere

Underground Sea

Rock solid

Magnetic

Whistles a tune