What is the evidence for a liquid water ocean on Ganymede?

(CNN) The Hubble Space Telescope has spied evidence of water vapor in the atmosphere around Jupiter’s moon Ganymede, the largest moon in our solar system. The water vapor forms as the icy surface of the moon turns from a solid to a gas, a process called sublimation.

Why do some of Jupiter’s moons have liquid water oceans under the ice?

Scientists’ consensus is that a layer of liquid water exists beneath Europa’s surface, and that heat from tidal flexing allows the subsurface ocean to remain liquid.

Can Ganymede support liquid water?

Jupiter’s moon Ganymede is the largest moon — and the ninth-largest object — in the Solar System. It may hold more water than all of Earth’s oceans, but temperatures there are so cold that water on the surface freezes and the ocean lies roughly 160 kilometres below the crust.

Does Ganymede have a solid or liquid core?

Ganymede’s interior appears to be fully differentiated, consisting of a solid inner core made of iron, a liquid iron and iron-sulfide outer core, a silicate mantle, and a a spherical shell of mostly ice surrounding the rock shell and the core.

What is the evidence for a liquid water ocean on Ganymede and why is this interesting to scientists searching for extraterrestrial life?

Also, a weak magnetic field implies the presence of a liquid layer below the surface. This is interesting for searchers of extraterrestrial life because liquid water is essential for life as we know it, and life seems to exist in most places on Earth where liquid water is found.

Does Callisto have liquid water?

Investigation by the Galileo spacecraft revealed that Callisto may have a small silicate core and possibly a subsurface ocean of liquid water at depths greater than 100 km. The surface of Callisto is the oldest and most heavily cratered in the Solar System. Its surface is completely covered with impact craters.

Does Ganymede have water?

Jupiter’s moon Ganymede is the largest moon — and the ninth-largest object — in the Solar System. It may hold more water than all of Earth’s oceans, but temperatures there are so cold that water on the surface freezes and the ocean lies roughly 160 kilometers below the crust.

Why does Ganymede have a salty ocean?

Its density is low, meaning it probably is a mixture of rock and ice—that’s common for moons in the outer planets. In the 1990s, the Galileo spacecraft flew past the moon several times, and careful measurements of its magnetic field indicated it might have an ocean of liquid water deep under its surface.

What is special about Ganymede?

Ganymede is the largest moon in the solar system, and is larger than the planet Mercury. If it were not orbiting as Jupiter’s largest moon, it could be considered a dwarf planet. Ganymede is the only moon in the solar system known to have a substantial magnetosphere.

How does Ganymede have a magnetic field?

Ganymede’s magnetic field is probably created by convection within its liquid iron core, also created by Jupiter’s tidal forces. The meager magnetic field is buried within Jupiter’s far larger magnetic field and would show only as a local perturbation of the field lines.

Why is Ganymede not a planet?

A planet needs to orbit the sun, AND have cleared its orbit of other objects. Titan orbits Saturn, not the sun, so it doesn’t qualify. For the same reason Ganymede, a moon of Jupiter, is not a planet (though it is larger than Mercury). Both Ganymede and Titan orbit another planet, which makes them moons by definition.