13 January

13 January was considered an unlucky day, at least in Britain.

Escaping from the Speardroids, the Tenth Doctor and Rose Tyler, through use of the ineffective randomiser, arrived somewhere even more unlucky: on the 13th moon of the 13th planet of the 13th galaxy, on the 13th day of the 13th year of the 13th century, on a Friday. There, they were struck by lightning and rained on by cats, and they met the Triskaidekaphobes, considered the unluckiest people in the universe. Little did they know that this was for a reason: Bob Kreesus was extracting the moon's luck to make himself incredibly lucky. In the end, he was defeated by the Doctor, and, now no longer lucky, slipped on a banana peel and fell off a cliff. (COMIC: Triskaidekaphobia)

13 January was the annual Slitheen family reunion. (PROSE: Time Traveller's Diary)

Behind the scenes
This was a reference to the fact that the comic story was featured in the thirteenth issue of Doctor Who Adventures. The story, in its entirety, was a reference to.