A new water world has been discovered in the Solar System: find out its location and see the photos.

Scientists currently have substantial evidence that the Jovian moon Europa indeed harbors a subsurface ocean of liquid water. There is even a possibility that extraterrestrial life could exist there. Now, new evidence has emerged suggesting that another Jovian moon, Callisto, is also an oceanic world. This research has been published in the journal AGU Advances, according to Universe Today.

Callisto is the second largest moon of the gas giant and the third largest moon in the Solar System. The first indications that there may be a subsurface ocean were discovered by astronomers 25 years ago.

Callisto has a different appearance compared to Europa and Saturn's moon Enceladus, which, as observations indicate, also have oceans of liquid water beneath their icy surfaces. However, the evidence for an ocean on Callisto is not related to the appearance of its surface and ice.

The primary evidence supporting the existence of an ocean on Callisto comes from the moon's magnetic field. Unlike Earth's magnetic field, which is generated in the planet's core, Callisto's magnetic field is induced. This means that it is created through the interaction of Callisto with Jupiter and its extremely powerful magnetic field. For Callisto to induce a magnetic field, it must have a layer of conductive material. Scientists believe this layer is an ocean of liquid water.

It was previously thought that induction within Callisto's ionosphere accounted for a significant portion of the observed magnetic fields. It was assumed that ionospheric induction generates induced magnetic fields somewhat similar to those expected from a subsurface ocean of water.

The new study, based on data from the Galileo spacecraft (which studied Jupiter and its moons from 1995 to 2003), shows that Callisto has a subsurface ocean that is responsible for the moon's magnetic field.

Researchers developed a four-layer model of Callisto, which includes the moon's ionosphere. In this model, they varied the thickness of the ice crust, the thickness of the ocean, and the level of conductivity. The study's authors concluded that the moon's magnetic field is likely due to a combination of a thick conductive ocean and the ionosphere.

Astronomers also concluded that the ocean's thickness from the seabed to the ice crust is several tens of kilometers, with the crust itself possibly being several tens of kilometers thick as well. This is indicated by the geological features of the surface.

The presence of an ocean on Callisto can be confirmed by the Europa Clipper and JUICE spacecraft, which are currently en route to Jupiter. Europa Clipper is expected to perform nine flybys of Callisto at distances ranging from 250 to 1800 km, while JUICE will conduct 21 flybys at distances from 1000 to 7000 km. Both spacecraft are anticipated to reach the Jupiter system in 2030 and 2031, respectively.