Fifth planet (hypothetical) Fifth planet (hypothetical) In the history of astronomy, a handful of Solar System bodies have been counted as the fifth planet from the Sun. Under the present definition of a planet, Jupiter is counted as the fifth. There are three main ideas regarding hypothetical planets between Mars and Jupiter. During the early 19th century, as asteroids were discovered, they were considered planets. Jupiter became the sixth planet with the discovery of Ceres in 1801. Soon, three more asteroids, Pallas (1802), Juno (1804), and Vesta (1807) were discovered. They were counted as separate planets, despite the fact that they shared an
The Guardian of the Solar System its "astonishing" imagery. 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