>>4002797There is a large rocky core surrounded by massive clouds of gas. For example in Jupiter's case, the rocky core is estimated to be about the size of the Earth, but is surrounded by clouds of gas that are 11-12 times thicker than the Earth. The Great Red Spot is about the radius of the Earth for comparison. Moons orbit Jupiter and all of our gas giants as well, some of these are as large as the planet Mercury but with less gravity (Ganymede). One of the moons around Saturn, Titan, has an atmosphere that is of similar pressure to Earth's but is almost all Nitrogen and about 50% higher pressure than Earth's atmosphere.
