Earthbound - S1-E17
Audio problem: McCauley and the engineer take a space walk to repair the ship's engines. We hear their tools clanking against the metal hull as the repair is made, and they pound loudly on the hatch door to reboard the ship when they've finished. None of these sounds would be audible in the vacuum of space.
Moon Cloud - S1-E20
Visible crew/equipment: When Carter follows McCauley and Holcomb to the moon crater, a sound equipment shadow moves across a rock in the foreground. (00:19:15)
Earthbound - S1-E17
Continuity mistake: The engineer's neck and shirt collar are burned when the instrument panel shorts out. Next shot, as he enters the cabin, the burns have vanished.
Factual error: The supposedly-British rescue ship has distinctly American markings on its sides. (00:19:40)
Is There Another Civilization? - S1-E24
Visible crew/equipment: When the news reporter tries to grill McCauley about the space collision, the boom mike dips into the shot at the upper right of the screen. (00:05:00)
Is There Another Civilization? - S1-E24
Factual error: The huge piece of retrieved space debris breaks loose in the hold and the astronauts struggle to lift and re-secure it. Only they shouldn't have had to. They're in space with no gravity generator, wearing magnetic boots to hold themselves to the deck. The debris would be weightless, too. (00:20:00)
Factual error: When McCauley and Rennish find the body of a previous moon explorer, they play back a message he left on a portable tape recorder. But they shouldn't be able to hear this: there's no atmosphere on the moon to carry the sound waves. Even if there were, their pressurized, self-contained spacesuits would still prevent them from hearing the tape. (00:19:30)
Contraband - S1-E21
Visible crew/equipment: While the crew are holding a conference inside the moonbase, an equipment shadow moves across the top left of the screen. In the same scene, a poor choice of camera angles also places two diagonal white ribs of a hatch door directly behind James Coburn, resulting in the bizarre impression of antennae growing out of his character's head. (00:12:00)