(Around 47 minutes) the Doctor's scarf is caught in the Tardis door as he escapes from the sphere but is no longer there when the Tardis materialises.
(Around 35 minutes) the professor is wearing his glasses when the sphere comes out of Skagra's bag but when it attaches to his forehead the glasses have disappeared.
For the first two-thirds of the story, Clare's hair is pulled back and tied in a bun. Then starting with the scene where she learns to fix and fly a TARDIS, her hair is loose and in large wavy curls, which it couldn't be even if she'd released her hair from the bun; it's too well-styled. Then in the dénouement, her hair is back up in a tight bun.
The period table next to the xray machine has element 104 with the symbol Ek. When discovered, the first proposed name for element 104 was kurchatovium with the symbol Ku and the International Union of Pure and Applied Chemistry adopted the temporary systematic name unnilquadium (Unq). It was finally named rutherfordium (Rf) in 1992. There is no element with the symbol Ek.
After the TARDIS materializes in the field where the giant invisible spaceship resides, he feels around and defines the ship's shape and location, then exclaims, 'What's that red carpet doing over there?' and proceeds to walk right through it.
This Goof must be for another version. In this 2017 completed version he walks on it, not through it.
This Goof must be for another version. In this 2017 completed version he walks on it, not through it.
In an odd goof, the analog clock on the wall of the lab where Claire meets the Doctor has the hour hand in the wrong position. The shorter hour hand is between the one and the two but the longer minute hand is on the twelve instead of six to show the time as 1:30. If the minute hand is correct then the hour hand should point directly towards the one or the two.
When Chris Parsons and Romana are discussing that the professor isn't human, a boom mic is seen at the top of the frame over Chris.
When Romana is asking Professor Chronotis about the person who has the book, she asks, "Was he tall, short?" But she first lowers her hand when she says "tall" and raises it when she says "short".