Character mistake: During the television report about the Sun Probe, a diagram shows the solarnauts' control cabin within the Probe Module. But we later see that the control cabin is within the body of the Probe Rocket when the Module is fired into the solar prominence.
The Alexander the Greater Affair (1) - S2-E1
Character mistake: When Alexander organizes the human chess game in his courtyard, the "pieces" stand the wrong way on the board, with a dark square in the lower right hand corner. That corner is always a light square. (00:22:50)