Goof: When Dr. Smith meekly ushers Quano's father toward the Robinson camp, actor Michael Ansara turns his back to the camera and you can clearly see the skull cap he is wearing.
A.P. Tucker is heard calling Will Robinson "Bill". This is the only time in the entire series where that happens.
Trivia: The book that Penny is reading is Nancy Drew #19, The Quest of the Missing Map. Some of the details on the back of the book are covered over.
The phrase "Oh the pain...the pain..." is uttered for the first time in this episode and will go on to become Dr. Smith's signature line.
Smith sends the Robot off to warn the Robinsons after it has been stated by the Robot that the outside temperature is well above freezing. But, when the Robot is shown traveling toward the Robinsons, he appears to be walking over the frozen inland sea.
Don and John are walking outside in the apparent freezing cold on this planet. While having to hide from the giant cyclops, it apparently wasn't very cold in the studio where they filmed the scene, as a closeup of the two actors in their heavy winter clothing reveals beads of sweat on their faces.
First appearance of the "Chariot" vehicle.
First appearance of Penny's "space monkey" pet, Debbie. The animal appeared briefly in the unaired pilot, but this was its first appearance in the series.
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.
Before becoming lost, the Jupiter 2 would have reached Alpha Centauri, a distance of approximately 4 light years, in about 5 years. However, the spaceship was written off by Alpha Control and declared beyond the limits of the Milky Way, but the closest edge of our galaxy is 25,000 light years showing this to be impossible.
Dr. Smith states he has won three GM (Grandmaster) titles at the Oxford University Chess Society. In fact this goes against the actual rules of the world chess organization FIDE (World Chess Federation) that state a chess title is won for life.
In this episode, the first of the regular series, it's heard that the Robinson's voyage has taken five years so far. This differs from the 98 years that had been stated in the unaired original pilot.
Dr. Smith holds the rank of Colonel.
The space ship that the Robinsons are launched in is called the Gemini XII, as an extension of the old Gemini space program. This will be changed to the Jupiter II in the regular series.
Maureen and John Robinson have a rare on-screen kiss.
The Gemini XII uses liquid oxygen or LOX, one of the physical forms of elemental oxygen, which is used by NASA to this day.