When Paul Foster is trying to board the renegade Russian surface probe, a red suited alien is reflected in his visor yet an alien on the surface of the moon has no part in this story.
On at least two occasions, the long shots of Straker's car shows a different driver from Straker. In the first, on the post opening credits, a brunette driver is shown as oppose to Straker's white hair. Later, in the first chase of of Jo Frazier, a man in a dark suit is shown when Straker is in a light suit.
During the final scenes of the runaway drilling probe, SHADO space helmets/suits change between scenes. In the first shot of Gay Ellis and Joan Harrington in space suits, their helmets and shoulder attachments are gray but in the next shot when they are lowering their visors, these parts are now yellow. When Paul Foster is in the moon mobile, his helmet is of a ridged "forehead" design yet when he is one the surface, it has become a smooth forehead design with a noticeable slope cliff attachment at the top of the helmet that wasn't there before. Still the same color, however.
The journalist drives an early Porsche 911 Targa with a zip out rear window. During the car chase, the zip out rear window is randomly in place or removed.
"There are several scenes showing cars driving on the right hand side, yet this series is set mainly in Great Britain, where cars drive on the left hand side."
Although this was the case in 1969 when the series was shot (and still is today) it's clear from other episodes where cars are seen driving on the right that this was one of the many predictions the show was making about the 1980 of the future.
In the shots of 3 UFOs, there is another object visible from an earlier episode, indicating a reused shot.
In the model shot showing the Sovatek mobile rig approaching the crouching Foster as he is about to attempt to board it, the model figure representing Paul actually vanishes a few frames before the rig potentially hits him.
Straker's suit while pursuing Jo Fraser is the wrong color.
Only one moonmobile has been dispatched to confront the Russian moon vehicle. However, at the 35:00 mark, as the moonmobile is traveling from left to right across the frame, there are a few frames just before the scene cuts away where a second moonmobile is shown entering the frame on the left.
When Straker is given the telephone by the barman, it's quite clear that it doesn't have any cables connected to it.