The producers approached Bruce Springsteen to appear in the episode because he had participated to the charity song "We Are the World", on which "We're Sending Our Love Down the Well" is based. Springsteen declined so the producers offered the role to Sting instead.
Homer stating that Sting is a good digger refers to the fact that Sting worked as a ditch digger as one of several other professions before he became a full-time musician.
Originally, after Homer panics over Bart's phony alien invasion message, he is seen mixing a punch bowl filled with Kool-Aid and rat poison in the kitchen. The censors objected to the suicide reference (and thought that more impressionable viewers would be drawn to imitating what Homer did), so the writers changed it to Homer getting a shotgun and running out to defeat the aliens (only to realize that it's Bart).
Argentinian rock band Timmy O'Toole took its name from this episode.
While down in the tunnel they've dug, Apu tells the crew that a nearby canary has died. Canaries were used by miners in the old days of mining to detect the release of poisonous gases. The episode stars Sting, whose band The Police recorded a song called "Canary in a Coal Mine".