Solar System largely of materials with lower melting points. The boundary in the Solar System beyond which those volatile substances could condense is known as the frost line, and it lies at roughly 5 AU from the Sun. The objects of the inner Solar System are composed mostly of rock, the collective name for compounds with high melting points, such as silicates, iron or nickel, that remained solid under almost all conditions in the protoplanetary nebula. Jupiter and Saturn are composed mainly of gases, the astronomical term for materials with extremely low melting points and high vapour pressure, such as hydrogen, helium,
HD 147018 b was discovered on the same date as this planet, on August 11, 2009. HD 147018 b HD 147018 b is a gas giant extrasolar planet which orbits the G-type main sequence star HD 147018, located approximately 140 light years away in the constellation Triangulum Australe. This planet has minimum mass more than twice that of Jupiter but this planet orbits a lot closer to the star than Jupiter to the Sun by a factor of 22. Meanwhile, it has an eccentric orbit. The planet can get as close to the star as 0.13 AU or can get as far as