Around the same time (1973) there was also a live action PSA about pollution with teenage actors playing Kirk, Spock, and McCoy that aired on the Washington, DC, UHF television station WDCA Channel 20. It was low budget, 3 actors in front of a blue screen or projection screen to simulate them beaming down to a polluted planet and commenting on how Earth's 20 century had a similar problem. The polluted planet background was either rear projected onto a screen or was added during post production.
Navigator NCC-2120 USS Entente
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