The green lights were sighted over Los Alamos Military Base, New Mexico, which is where White Sands Missle Range is located and the site of the first atomic blast at the Trinity Site by the US scientists in 1944-45.
The episode is loosely based on the green fireballs spotted around nuclear military installations and Project Twinkle designed to track and explain them.
Dr. Hynek makes the major faux pas that most TV series do and calls the comet Hayley's, it's Halley's comet.
By 1948, the project was still called Project Sign, not Project Blue Book as that moniker wasn't used until 1952, but in the end credits information they clearly stated the incident occurred in 1948 and under Project Blue Book.
There is a White Sands Missle Base/Range. In the program White Forrest is possibly based on the real-life White Sands Missle Site, New Mexico.