Corrected entry: As Larrin is looking for the wraith aboard the Lantian warship she is using an Ancient life signs detector, which she should not be able to use as she doesn't possess the Ancient gene necessary to operate Lantian technology, hence her need to keep John Sheppard around in the first place. (00:30:00)
Corrected entry: When Sheppard and Zelenka are repairing the damaged hyperdrive control array, Zelenka pulls a crystal out of a panel and then lets go of it, the crystal flies up and out of his hand when they are in a zero gravity environment. (00:32:20)
Correction: The control crystal floats away because the city is moving through space and the crystal is no longer connected to the city in some way. This means that even though Zelenka just let it go the crystal should float off as Zelenka is connected to the moving city by the magnetic boots of his suit and the crystal is not.
Doppelganger - S4-E4
Corrected entry: When Dr. Jennifer Keller is talking about her dream (basically re-telling the scene from the movie Alien when the parasite came out of the body of Teyla Emmagan), Ronon Dex says, "It sounds like that movie," referring to the movie Alien. He did not come from Earth and yet he knows already about Alien the movie. Sure, Lt. Colonel John Sheppard could have told him about it, but it seems curious that he just recalls it so vividly without ever seeing the movie.
Correction: By season four Atlantis is no longer cut off, Daedalus makes regular supply runs from Earth. Ronon has doubtless seen dozens of movies by this point.
Correction: McKay states in one of the first episodes that the Lantean lifesigns detectors (along with other pieces of technology) are able to be used by anyone once activated by someone with the ATA gene.