While they might have near-solid inner cores of molten heavy metals, … Gas giants are also called “Jovian planets,” named after Jupiter; To be considered a gas giant, the planet has to be made up of mostly gas, be located in the outer area of the solar system, and have a mass that is ten times that of Earth. Gas giants are sometimes known as failed stars because they contain the same basic elements as a star. The gas giant … There are four planets in our solar system that are collectively known as the “gas giants,” a term coined by the twentieth-century science fiction writer James Blish. They are also called “Jovians,” as Jove is the Latin name for Jupiter, the largest of the four. Neptune, Uranus, Saturn and Jupiter are the gas giants of our solar system.The general belief is that these gas giants formed first as icy and rocky planets similar to the terrestrial planets Mercury, Venus, Earth and Mars. They do not orbit anything other than a star. Actually, dwarf planets are classified as such because they are actually small enough to become the moon of a planet, or be considered an asteroid. The term "gas giant" was originally synonymous with "giant planet", but in the 1990s it became known that Uranus and Neptune are really a distinct class of giant planet, being … Gas giants are large enough to be a planet.

Gas giants are called such because they are much larger than terrestrial planets and are composes largely of hydrogen and helium. The gas planets are made up almost entirely of gases, primarily hydrogen and helium. All planets start off as random collections of rocks (and in the outer solar system, where’s it colder, ices).

The outer planets of the Solar System - Jupiter, Saturn, Uranus and Neptune - are gas giants, a designation which applies to planets that are primary composed of hydrogen and helium. A gas giant is a gargantuan planet composed mainly of gases that include helium and hydrogen with a comparatively small rocky core. Jupiter and Saturn are the gas giants of the Solar System. A gas giant is a giant planet composed mainly of hydrogen and helium. The outer planets (with the exception of the dwarf planet - Pluto) are called "gas giants" for two reasons - they are GIANT (in size/mass/gravity etc.) Scientists refer to the atmospheres of Saturn and Jupiter as being more “polluted” because they have larger percentages of heavy metals such as methane and ammonia.