Other mistake: One of the episodes shows John at a Marine base camp. It shows him wearing Army fatigues, and in Episode 7, Maureen jokingly says "weren't you a Navy SEAL?" right after he fails to throw this hook to get to safety from a tar pit. So what is he? A soldier? Marine? SEAL? Can't be all three.
Suggested correction: Navy SEALs will wear camo to disguise themselves.
SEALs are Navy. So John is a Navy guy in a Marine Corps base using Army fatigues? A bit messy I guess.
Military folks end up on various bases all the time. I was in the Navy for 20 years and found myself, at different times, operationally committed to being on Army, Air Force, Coast Guard bases, and plenty of other bases with Marine detachments, to say nothing of bases of foreign militaries overseas. If you happen to be on a joint operations base, like European Command, you'll see everything walking around. Not as odd as it sounds.
Factual error: At the start the Robinsons are playing a game of fish, in weightless or free fall conditions. At about 1:30 the computer announces "Completing De-Orbit Burn." De-Orbit Burn involves deceleration. This is not free fall, they should be experiencing the deceleration and hence a sense of gravity. The cards should not float. (00:01:30)
Other mistake: Right at the start, as they're crashing, the computer narrates their rapidly-dropping altitude in feet. But the "altitude" dial we're shown is in metres. Most noticeable as they cross the 3,000 mark, when the computer voice and the height say/show the same number at the same time, despite the different units. 3,000m would be more like 9,000 feet, or 3,000 feet would be more like 1,000m. (00:03:20)
Factual error: John Robinson, a United States Marine, is seen wearing an Army combat patch (1st Infantry Division). (00:44:05)
Plot hole: The show starts with the Jupiter crashing into the planet... also the other Jupiter seems to have had problems landing on the unnamed planet... why? The Jupiters were fully capable of flying around the planet as we saw it in other moments. None of them were attacked by the robot, they are not escape pods. So why crash land into the planet? Also why get out of the ship just to be stranded on an icy hellhole? The space ship is waterproof, as we saw in another episode. So why get out just to have one person go in again and get trapped on ice? And that's just the tips of the iceberg, pun intended.
Infestation - S1-E3
Character mistake: When Maureen Robinson says that the ship is "trillions of light years" away from Earth, she should have said miles instead of years. A later episode correctly changes the distances involved to "trillions of miles."
The Robinsons Were Here - S1-E4
Continuity mistake: Penny is holding an envelope in her hands, then turns around to follow the siblings and the envelope is gone. Just a cut later Penny has the envelope back. (00:32:30)
The Robinsons Were Here - S1-E4
Revealing mistake: After going beyond the perimeter fence for the first time, the children initially find the flowers that bloom when they each clap. When the robot motions to clap, you can see its left hand lost to the CGI flowers.
Continuity mistake: Don West is wearing Dr. Smith's necklace, even though it was lost in the storm. The necklace is then not there or removed in the next shot. (00:31:30)
Pressurized - S1-E7
Continuity mistake: When Judy is trying to keep Evan alive in the vehicle, sometimes there is a seat belt across his chest, and other times it is gone. (00:28:00)
Trajectory - S1-E8
Continuity mistake: When John is under the panel with Will, right before Will hands him the flashlight, the way Will is gripping the flashlight changes between shots. His pinky is either on top or underneath.
Danger, Will Robinson - S1-E10
Plot hole: At the end, when Maureen is searching for John in orbit, she only radios him after Will sees him clinging to the floating wreckage. Before that, she only used sensors aboard Jupiter to try and locate him. She makes no attempt at radio contact for any survivors, which would have quickened the rescue. John can also radio her back, but he did not attempt to call for help.
Suggested correction: The suit radios are fairly short range. This is seen on a number of occasions, such as when they need an extension antenna when stuck in the tar to contact others. The distances in space between the damaged Jupiter and Jupiter 2 are huge, and much further than the distance from the chariot stuck in tar back to Jupiter 2.
Continuity mistake: When Judy is talking with Victor Chariot 8 is on the right side of the C19, then it is on the left side almost immediately.
Continuity mistake: When Will introduces Robot to Gypsy, in the following shots Gypsy's blaze changes shape, revealing different horses portray Gypsy.
Shell Game - S2-E9
Revealing mistake: While Maureen and John are piloting their two maintenance pods, in the closeups which face each of them head-on, note the walls behind them have numerous identical smudges in their individual pods, which is especially noticeable in consecutive closeups.
Character mistake: When John and Judy are running from the Robots he shouts "Run Penny!" even though Penny is not there. (00:34:21)
The New Guy - S3-E3
Visible crew/equipment: After Penny asks everyone on the ship to double-check that everything is tied down, when Will tells Robot that he thinks he found something to help them later, there's a yellow T-mark taped to the floor which is visible at the bottom of the screen. (00:31:20)
Continuity mistake: At about the 30-minute mark, right after Judy and Maureen have a heart about being the perfect daughter, Maureen says "you have to get out of here." When she says this, she slips out of her harness and her shoulders come loose, which is the only reason the two can't leave the ship easily. The next shot we see of Maureen she is back in her harness. (00:30:10)