Sirius 5

Sirius 5 (COMIC: The Arts in Space) was a planet that contained the Academia Stellaris, considered by Romana II to be one of the greatest art galleries in Mutter's Spiral, though the Fourth Doctor considered the Louvre better. (TV: City of Death)

The Prolocutor of the Babblesphere was copied onto a hard drive by the Fourth Doctor and donated to the Library of Artificial Intelligence in the Academia Stellaris on Sirius V. (AUDIO: Babblesphere)

The Tenth Doctor later offered to take Gabby Gonzalez to the gallery, before deciding on a better one. (COMIC: The Arts in Space)

Behind the scenes

 * In NOTVALID: Doctor Who and the Warlord, the Sixth Doctor describes a Time Lord known as the Warlord who, while once dedicated to stopping war, has since become obsessed with changing history to extend wars across history. In the opening text to Part B, he notes that this previously included giving "the cave people" of "Sirius V" fire.