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
Devil's Planet Devil's Planet "Devil's Planet" is the twenty-second episode of the second series of the British sci-fi television series "" (and the forty-sixth overall episode of the programme). The screenplay was written by Michael Winder; the director was Tom Clegg. The original title of the episode was "Devil's Moon". The final shooting script is dated 9 September 1976 and live-action filming began on Monday 1 November 1976 lasting through to Thursday 18 November 1976. The episode was first broadcast in the U.K. on 1 September 1977. 2306 days after leaving Earth orbit, the Moon is passing a solar system containing a