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Colonel Orson Pink was a human pioneer of time travel from the 22nd century.
Orson bore a striking resemblance to Danny Pink, a soldier and mathematics teacher from the early 21st century. When Orson took off his helmet, Clara Oswald thought it was Danny. According to "silly stories" told about one of Orson's great-grandparents, time travel ran in the family. (TV: Listen) According to the Twelfth Doctor, even though they had the same surname, Orson "[did]n't look anything like" Danny. Clara claimed that he looked "very like him". The Doctor responded, "Does he? I dunno. Who remembers a PE teacher?" (TV: The Caretaker) The Twelfth Doctor assumed that Orson had "something to do" with Clara Oswald's timeline. (TV: Listen)
Orson rode the first of the great time shots. He was supposed to have been fired into "the middle of next week", but the experiment failed, and he ended up at the end of the universe, where he remained for approximately six months. Despite being alone, he continued to keep the doors of his habitation locked. Orson suspected there were creatures in the darkness, so he wrote a warning on the airlock of his shuttle to never open his craft to the featureless universe outside.
He was discovered by the Twelfth Doctor and Clara, when they were using the telepathic circuits of the Doctor's TARDIS.