The large white chamber shown in the lab is actually a thermal/vacuum chamber which simulates the vacuum of space and the temperature extremes encountered in orbit (-300 to +300 degrees F). The chamber is still used in testing satellites prior to launch.
Most of the "military base" exteriors and laboratory scenes were filmed at TRW Space & Defense (now Northrop Grumman Space Technology) in Redondo Beach, California.
The bizarre electronic sounds heard as the Venusian creature approaches the space capsule were taken from a recording called "Noise Study" by James Tenney. It first appeared on a 1962 record album called "Music From Mathematics, Played by IBM 7090 Computer and Digital to Sound Transducer." Its use in this episode marks the first time digitally generated sounds were heard in any movie or television show.
A photograph on a table behind the desk in the living room depicts Martin Landau, who previously appeared in The Man Who Was Never Born (1963) and The Bellero Shield (1964).
William Shatner's character mentions "Project Vulcan," Vulcan being the name of a race, which includes the major character, Spock in his later series Star Trek (1966).