- You may be looking for Kasterberous system.
The Sixth Doctor mentioned that Kasterborous was made up of seventeen suns. (AUDIO: Trial of the Valeyard) When explaining where they were from, the Doctor sometimes mentioned that Gallifrey was located in Kasterborous, (TV: Attack of the Cybermen, Voyage of the Damned, The Day of the Doctor, Spyfall; AUDIO: An Earthly Child) as did Jack Harkness and Clara Oswald while pretending to be the Doctor. (AUDIO: Piece of Mind, TV: Death in Heaven)
The name originated from Kasterborus, an astrologist who gave the largest contribution to "neo-astrology", occurring between the third millennium and the beginning of the fourth millennium. The Time Lords appointed one of their constellations with that name, due a rare display of humour from the race. (PROSE: Introduction and links)
During the War in Heaven, Kasterborous was torn apart and erased from history when the Eighth Doctor used the Edifice to destroy Romana III's Gallifrey. In the post-War universe, Marnal was unable to find Kasterborous anywhere in space or time. (PROSE: The Gallifrey Chronicles)