What distinguishes jovial planets from terrestrial planets?

Jovial planets, also known as gas giants, are distinguished from terrestrial planets primarily by their size and density. Gas giants like Jupiter and Saturn are significantly larger and less dense than terrestrial planets such as Earth and Mars. While terrestrial planets have a solid surface composed primarily of rock and metal, jovial planets lack this solid surface characteristic and are instead composed mostly of gaseous materials and, in some cases, have a small, solid core. This significant difference in composition correlates closely with their sizes; jovial planets can have diameters that are tens of times larger than terrestrial planets.

Additionally, while atmospheric composition is a relevant factor in distinguishing these types of planets, it is fundamentally tied to their size and density. Terrestrial planets have thinner atmospheres while jovial planets have thick atmospheres composed of hydrogen and helium. Proximity to the sun affects temperature and potentially geological activity, but it does not specifically distinguish between jovial and terrestrial categories in the same context as size and density.