Continuity mistake: During the scene where Jenny is on the dock trying to interview Secretary Rittenhouse, the sun changes position a few times during the scene. When Jenny is talking to the little girl, the sun is behind Jenny appearing to be the middle of the afternoon. When Jenny walks to look over at the cargo, the sun is now ahead of her to the west, getting closer to sunset. When Rittenhouse appears on the boat, the sun is back to the previous position, for a second until the camera pans back to Jenny with the sun out west again. Rittenhouse ushers off his daughter & she walks off as Jenny tries to talk to him, all the while the sun is now behind Jenny to the mid afternoon setting. When Rittenhouse walks off, the camera pans around and now the sun is in the west again near sunset and remains this way until the end of the scene. (00:12:30)
Continuity mistake: When they are on the motorcycle near the end, he is first traveling with the flow of traffic that is stopped (west). When she gets on the bike with him and the baby, they keep going with the flow of traffic. Than the smaller asteroid enters the atmosphere, it is traveling in the same direction they are driving on the motorcycle. But when it passes the girl's family in the van, now the asteroid is traveling against the flow of traffic (east).
Factual error: The shock wave that hit Messiah when it detonated the nuclear bomb on the comet would not have existed in space. It may have been hit by debris, but that would have destroyed the craft.
Factual error: A wave 1000' high would have obliterated the containments and wiped out the spent fuel pools of every nuclear plant on the east coast. Even if they were all shut down, there would be no time or way to remove all the fuel and no place to safely store it all if they did. There are thousands of metric tons of fuel that have to be actively cooled for years, otherwise it would all catch fire and burn, or at the very least boiled all its cooling water away and melted/uncovered it to allow gamma shine. This would have, in and of itself, made the northern hemisphere uninhabitable for several hundred human lifetimes.
Continuity mistake: When the boy takes the motorbike from the garage the mirrors are out of line. In the next shot before he rides out, the mirrors are all in line.