The comet is shown to radiate light and heat. Comets are balls of ice that do not radiate heat, and only reflect light if there is a star in the vicinity.
When Will, Penny, and Judy look out the porthole at their parents, Will is standing in the front. However, when the camera cuts to a shot from behind, Will is in the back.
Despite the fact that John informs Smith that he will be treated as a stowaway, and suspects he tried to kill them, he gives Smith a gun when they leave the ship.
When John uses his gun to burn through the wall, there is no beam. When he turns to shoot at the aliens, there is a beam. Also, the wall continues to burn even after John stops firing and goes into the ship.
When the Jupiter 2 flies out of the alien hangar bay, the exterior shot shows four individuals on the bridge, standing widely apart. However, in the next interior shot, there are five people, standing closely together.
John: Let's get around to the other side, then.
Don: All right, if you insist.
John: Well, look at that thing! Where's your scientific curiosity?
Don: All in one basket - Alpha Centauri.
Unlike other episodes, there is no opening trailer. The show starts immediately with the credits and theme. The title, writer, and director credits don't appear until the start of the second act.