Gas giant Gas giant A gas giant is a giant planet composed mainly of hydrogen and helium. Gas giants are sometimes known as failed stars because they contain the same basic elements as a star. Jupiter and Saturn are the gas giants of the Solar System. 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 composed mainly of heavier volatile substances (which are referred to as "ices"). For this reason, Uranus and Neptune are now often classified in the separate category
The Guardian of the Solar System The Guardian of the Solar System The Guardian of the Solar System is a Big Finish Productions audiobook based on the long-running British science fiction television series "Doctor Who". The Companion Chronicles "talking books" are each narrated by one of the Doctor's companions and feature a second, guest-star voice along with music and sound effects. The First Doctor, Steven and Sara Kingdom find themselves inside a giant clock, the great secret of The Guardians of the Solar System. "Doctor Who Magazine" reviewer Matt Michael said that the audio was "excellent", describing it has having a "dark, haunting atmosphere", and praising