Arcturian system

The Arcturian system (COMIC: Junk-Yard Demon) also known simply as Arcturus, (PROSE: Only a Matter of Time) was a star system located in Mutter's Spiral.

Astronomical data
Giving the system its name, located at the centre of the system was the star Arcturus. (PROSE: Only a Matter of Time) The system was located 40 light years from the Sol system. (PROSE: Only a Matter of Time)

The Arcturian system had at least four planets, (COMIC: Junk-Yard Demon) including a planet simply known as Arcturus, (TV: The Curse of Peladon) Arcturus II (PROSE: Transit) AS4 (COMIC: Junk-Yard Demon) and Arcturus Six. (PROSE: Love and War) AS4 was orbited by two moons. (COMIC: Junk-Yard Demon)

History
Hailing from one of the planets in the Arcturus system, the Arcturians abandoned their planet due to a belief that their atmosphere was in the process of thinning due to the immense gravity of their star, a process they claimed would take a million years. To avoid their fate, the Arcturians set out across the galaxy to find a new home, setting their sights on the planet Earth, in the Sol system. Many generations into their journey, they encountered the Second Doctor, Polly Wright and Ben Jackson. Learning of their plan, the Doctor moved them into the Ninth Dimension, so that they could find a home there instead of the inevitable conflict with Earth. (PROSE: Only a Matter of Time)

A major power on the galactic stage were the Arcturans of Arcturus. (TV: The Curse of Peladon, PROSE: Legacy) They were particularly involved with the humans of planet Earth, attempting an invasion some time prior to 451 CE, (PROSE: Combat Magicks) signing a treaty with them in 2085 (PROSE: The Dying Days) and engaging in trade. (PROSE: The Janus Conjunction) Eventually, by the 39th century, Arcturus would be a member of the Galactic Federation. (TV: The Curse of Peladon)

The Fourth Doctor once visited AS4, which was home to palm-like plants and birds. AS4 was also the site of the wrecked command ship of a long-lost Cyberfleet, where the body of Cyber-leader Zogron was found. (COMIC: Junk-Yard Demon)