Riften 5, also spelt as Riftan Five, was a satellite of Vita 15. On Riften 5, the Fifth Doctor visited the vid-archives and saw genetic tests that were run on Daleks after the War of Sharpened Hearts. (PROSE: Christmas on a Rational Planet)
The satellite was a location Leela and the Doctor visited and got lost for three days.
Leela thought she recognised Riftan Five from a photo River Song uploaded to Bookface of her and the Eleventh Doctor running from the Judoon. The Judoon later caught up with River and the Doctor on level 17 of an underground bunker because River forgot to turn the location off on her Bookface account. (COMIC: Timeliney Wimey)