We wanted to find out the average cost to replace a roof in the UK so we assume the following when we contacted our chosen companies: 1  A detached house with a simple âup and overâ roof design. 2  Approximately 64 square metres.e wanted to find out the average cost to replace a roof in the UK so we assume the following when we contacted our chosen companies: 1  A detached house with a simple âup and overâ roof design. 2  Approximately 64 square metres.
Jovian Planet Characteristics. Jupiter, Saturn, Uranus and Neptune are the four jovian planets of the solar system. The density of these planets is less than that of the earth, as they are mainly formed of hydrogen along with helium and compounds of hydrogen such as methane and ammonia. The mass of these planets is more than 10 times that of the Earth. 2  They have very small cores as compared to the terrestrial planets. 3  Gas storms are a common phenomena on the surface of the jovian planets.
The Jovian planets, or Gas Giants are not all comprised of the same gases. The Traditional Jovian planets, Jupiter and Saturn, contain mostly hydrogen and helium with other â¦ heavy elements making about 3 to 10 percent of its mass.ovian planets can also be called gas giants. They are Jupiter, Saturn, Neptune and Uranus. They are mostly made up of gas, but they have a rocky core, (somewhere!). They are â¦ said to lack a solid surface, But they actually don't really have a surface at all!