Gas giant
From RationalWiki
A gas giant is a large planet consisting of gases (predominantly hydrogen and helium) held together by gravitation, although many gas giants also have a solid rocky core. Gas giants are one of two types of planets, the other being the rocky planets.
Gas giants are larger and more massive, but have lower densities, than rocky planets. Clearly, being gaseous they need to be more massive in order to generate sufficient gravity to hold themselves together. Jupiter, for example, has a diameter of 142,984km[1] (12 times that of Earth) and some exoplanets are even larger than Jupiter.
Gas giants are always incapable of supporting human life partly because they lack a solid surface, and because no human being could withstand the force of their gravity.
In our solar system, the Jovian planets (Jupiter, Saturn, Uranus and Neptune) are gas giants.
Most exoplanets that have been discovered so far are gas giants, and also in very close orbits. This is most likely because gas giants are large and thus more easy to detect than rocky planets via their gravitational effects on their star or occlusion of its light.
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[edit] On your calendar
Saturn, uniquely among the gas giants, has been honored by having the seventh (or sixth, depending on your personal issues) day of the week named after him: Saturday.
The Romans also called their year-end "our calendar is screwed up again" party "Saturnalia".
