When Doctor Higgins checks the time, a close-up shows his wristwatch against the cuff of his shirt. However, he is wearing a t-shirt.
The average surface temperature of the Jovian moons is about 250 degrees below zero Fahrenheit, an extremely inhospitable environment for men in shirt sleeves and women in bare feet and skimpy costumes.
The crew should be weightless during the transit to Jupiter.
It takes about 90 minutes for a radio signal to make the round trip from earth to Jupiter, yet the ground converses with the spacecraft without any delay.
At 10:00 when they commence the rocket launch, you can hear the clock ticking but the clock they are looking at is actually a Longines sweeping second hand that does not make a ticking sound.
The Los Alamos airport was a military base- closed to civilian traffic- until 1960. Furthermore, TWA never served it.
Whenever the all-controlling twin-lever guidance device is used, it clearly moves revealing it to be unattached to the flight panel.
You can see the trees through the rocket's tail-fin when it is landing on Jupitar 13.
A hand grenade bounces to the right and behind an altar, but the explosion comes from the front and center.
The anonymous actor playing the creature wears dark, tight-fitting clothing with visible zippers.
When the TWA flight lands at London Airport, the ground announcer indicates the plane is an Ambassador (Airspeed Ambassador), when it is really a Lockheed Constellation.
When the monster falls into the pit of fire, the mattress he lands on bounces up to the left of the pit.
A palm tree is visible in the background when the passengers are disembarking in London at the beginning of the movie.