Character mistake: During the debrief meeting with the generals, Roy states the Lima Project was "some 29 years ago" and "the ship disappeared approximately 16 years into the mission." A few minutes later, Roy narrates "I was 16 when he left, 29 when he disappeared." This of course is only 13 years into the mission. (00:11:27 - 00:15:03)
Factual error: Motion is physically wrong when he jumps on to the rotating scanner while floating in space above Neptune. Firstly he matches its rotation before he's even grabbed hold of it properly. Centrifugal force would rip him off it unless he's got a really tight grip on it. He even perches on the end of it, moving around in a circle, while not holding on. Violates Newton's 1st Law. (01:42:30)
Factual error: It is stated that at the start of the mission it is "almost full moon", the earth as seen from the moon must then be crescent, and not 3/4 full as seen on the buggydrive.
Factual error: In the movie, Neptune is shown having bright, wide rings. While the planet does have rings, in reality, they are very faint and thin. They were barely visible even from Voyager 2's flyby of the planet in 1989. They are nowhere near as big and bright as seen in the movie.
