I read that in a Star Wars dialog going upwards into space. Lol.In the beginning of television, it would go off the air at midnight (right after "High Flight").
It was common for stations to broadcast the national anthem as a sign off when going off the air for the night. Both local stations and networks did this in the 50s, 60s 70s and 80s. Being an old guy, I don't know about now as it is past my bedtime when they go off the air (if they even do) and besides I can't remember anything that new.
My favorite late night program as a kid was the Indian Chief test pattern. Man that guy could hold still. LOL