These are frames from the special effects storyboard for the episode Collision Course. Most year 1 storyboards were not coloured, but for this episode the planet Atheria is coloured in red and yellow.
In the original script (from 9th August 1974), Brian Johnson has marked up the SFX shots and sketched scene 74, when Koenig first sees the "mammoth spaceship shaped like a wingless vulture". The back page of the SFX scene list (dated 13 August 1974) with Brian Johnson's initial sketch of Arra's ship.