Factual error: When Mission Control talks with Challenger 2, the Spacecraft's camera feeds of the Crew are displayed up on two wall-sized TV screens. Between them is the familiar Mercator map of Earth with the ground track of a low-orbiting satellite superimposed. Challenger is nowhere near low orbit: it's out past Mars, in the Asteroid Belt. The middle screen would have a schematic of the ship's interplanetary path.
Continuity mistake: When the Siberian siblings have supper, one is sitting higher than the other, who's perpendicular to him. A shot later, they're parallel to each other and the smallest kid is now taller.
Revealing mistake: When the meteor is about to strike downtown Manhattan, the bay area image is a blatant photograph, with the boats and ripples completely still for several seconds. (01:19:49)
Revealing mistake: When the tidal wave floods the city and the road, one can see a thick line where the water footage was pasted over the city footage. Furthermore, all of the cars keep driving despite the chaos, and not a single object falls down.
Visible crew/equipment: In Hong Kong, when the people are running for their lives, check a group of bystanders on the left behind a safety barrier, calmly watching the filming.
Revealing mistake: Despite the heavy snowfall in Siberia, not a single flake falls on the people or clothes, nor is there any ice on them, revealing the snow is just footage matted over the scene.
Continuity mistake: When the tidal wave is about to break into the control room, the guy next to the window suddenly grows a toupee.
Continuity mistake: Before the wave enters the control room, there's a TV on the right. When the water breaks in, the TV disappears.
Visible crew/equipment: When Bradley is in the control room, the T-mark on the floor is visible. (01:12:30)
Character mistake: USA flags are supposed to be displayed with the Union (blue area) on top left corner, whether it's displayed horizontally or vertically. USA missiles at times displayed the flag backwards. Also, at the end of the movie, the flag hung on the hangar next to the USSR flag is backward. (01:40:57)
Continuity mistake: Malden enters a bar to meet Connery. Sitting on Connery's right is a white-hared guy, so Malden sits on his left. We switch to watch the TV, and when we return, Malden is now on Connery's right.
Continuity mistake: When we see Dr Bradley in the back seat of the limousine on his way to the meeting, he is wearing a white shirt and a black tie. When he arrives at the meeting room, he is now wearing a black shirt and striped tie.
Factual error: We're given to believe that the mission control in NYC is under the AT&T building on Thomas Street. The scene showing the destruction in Manhattan does not go south enough to have had any impact on this building, and the subway tunnels used to escape after mission control is damaged are nowhere near the Hudson river. The illusion given by the movie is that water sloshes up against the tunnel walls.
Factual error: All movies make the same mistake when depicting nuclear explosions in a vacuum. You get a large fireball which would melt but not destroy the asteroid. Pressure waves are generated only in an atmosphere.
