2022 IB Diploma Extended Essays

Io is tidal locked, where one face of the moon always faces Jupiter. This means that there is no longer any net change in the moon’s rotation in an orbit. This causes distortion and the gravitational force on one side to be greater, due to the mass of Jupiter. Yet the other moons continually change the degree at which Io is distorted. Tidal heating Tidal heating occurs in either or both the surface ocean or the interior of a planet or satellite due to tidal friction processes. The varying of the deformation of the object due to the tidal forces generates the internal friction, heating the interior. This energy is gained by its gravitational energy, which means that over time in a two-body system, the orbit will gradually become circular. Io will not return to a circular orbit due to the orbits of Europa and Ganymede, and how they consistently change the distortion of the moon, flexing its interior. This friction-induced heating is what causes the strong volcanic activity that occurs. (Moore, 2003) How volcanoes are formed Volcanoes are formed when magma chambers occur and empty, which are large pools of liquid magma that produce forces that tend to drive it upwards. These magma chambers on Io are similar but much larger than the ones that form on earth. This can be observed by the calderas on Io, which are tens of kilometers across. Calderas are large hollow spaces that form when magma chambers are emptied. These Calderas cave in on Io due to the molten interior of the planet. The location of the magma chambers and therefore, volcanoes on Io are influenced by where the magma is inclined to flow towards.

2 Further research 2.1 Io’s interior

The observed distribution of heat flow is due to interior heating and volcanic advection, the surfacing of magma, regardless of its where it originated from. The heat flow distribution is not uniform. The heat flow under the surface of Io, does not match the distributions that were expected from the end-member models for both the deep-seated (mantle) heating model and the shallow (aesthenospheric) heating model, which predicts enhanced thermal emission.

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